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Biology Articles; Food-And-Agriculture Articles | How can we save bananas from a deadly disease | Have you ever wondered why all bananas in supermarkets look This is because Cavendish bananas do not have an active gene to alike and taste exactly the same? Because almost all exported fight off TR4. However, a wild banana from Indonesia does - the bananas (Musa spp) are of a single cultivar, the Cavendish. Every RGA2 gene. single Cavendish is genetically identical; basically they are all Here, we added the RGA2 gene to Cavendish plants and tested clones! So what? them in fields infested with TR4. Three years later, some of these Cavendish bananas are under a threat from a disease called genetically modified (GM) plants resisted the fungus and stayed Panama disease, also known as Fusarium wilt Tropical Race disease free. That means we may have found a solution to control (TR4) that is caused by a fungus. It is spreading very fast and has TR4 and help millions of people who rely on bananas for food and already destroyed many plantations in Asia and Australia and has income. recently spread to the Middle East and Africa. | Banana (Musaspp.) is a staple food for more than 400 million people. Over 40% of world production and virtually all the export trade is based on Cavendish banana. However, Cavendish banana is under threat from a virulent fungus,Fusarium oxysporumf. sp.cubensetropical race 4 (TR4) for which no acceptable resistant replacement has been identified. Here we report the identification of transgenic Cavendish with resistance to TR4. In our 3-year field trial, two lines of transgenic Cavendish, one transformed withRGA2, a gene isolated from a TR4-resistant diploid banana, and the other with a nematode-derived gene,Ced9, remain disease free. Transgene expression in the RGA2 lines is strongly correlated with resistance. Endogenous RGA2 homologs are also present in Cavendish but are expressed tenfold lower than that in our most resistant transgenic line. The expression of these homologs can potentially be elevated through gene editing, to provide non-transgenic resistance. | https://www.nature.com/articles/s41467-017-01670-6 | Lower high school; Upper high school |
Biology Articles; Technology Articles | How can we simulate a lab-on-a-chip | Many chemical and biomedical experiments are conducted in labs that need a lot of space, expensive machinery, and special substances. What if this process could fit onto a tiny chip? Wouldnt that save a lot of time, space and money! So-called labs-on-a-chip (also called biochips) already exist but their design is tedious. Researchers still have to manually calculate a lot of the variables, which leads to the creation of lots of different possible chips, some of which wont prove useful. This trial-and-error approach takes a lot of time and money. What if we could create a virtual biochip before we physically make one so that we know we are always manufacturing the right one? Here we developed a computer simulation for a lab-on-a-chip and compared its predictions to existing biochips. We found out that our approach is great at its predictions, and chip designers could use it to create reliably useful biochips for lots of different experiments. | The functional performance of passively operated droplet microfluidics is sensitive with respect to the dimensions of the channel network, the fabrication precision as well as the applied pressure because the entire network is coupled together. Especially, the local and global hydrodynamic resistance changes caused by droplets make the task to develop a robust microfluidic design challenging as plenty of interdependencies which all affect the intended behavior have to be considered by the designer. After the design, its functionality is usually validated by fabricating a prototype and testing it with physical experiments. In case that the functionality is not implemented as desired, the designer has to go back, revise the design, and repeat the fabrication as well as experiments. This current design process based on multiple iterations of refining and testing the design produces high costs (financially as well as in terms of time). In this work, we show how a significant amount of those costs can be avoided when applying simulation before fabrication. To this end, we demonstrate how simulations on the 1D circuit analysis model can help in the design process by means of a case study. Therefore, we compare the design process with and without using simulation. As a case study, we use a microfluidic network which is capable of trapping and merging droplets with different content on demand. The case study demonstrates how simulation can help to validate the derived design by considering all local and global hydrodynamic resistance changes. Moreover, the simulations even allow further exploration of different designs which have not been considered before due to the high costs. | https://pubs.rsc.org/en/content/articlehtml/2018/ra/c8ra05531a | Lower high school; Middle school |
Biology Articles; Health-And-Medicine Articles | How can we trace malaria mosquitoes | Do you find mosquitoes annoying? Not only can they be quite irritating, but they also carry many deadly diseases. One method to control these diseases is to control the mosquito populations. But we have to know more about them how many there are, where they are, their mating behavior, etc. To do this, researchers most commonly use the mark-release-recapture technique. Current mosquito markers have some downsides, because they can change the mosquitoes behavior. This is why our research attempted to mark Anopheles mosquitoes with two dyes: rhodamine B and uranine. We found that both dyes are suitable for marking and tracking mosquitos. | Marking mosquitoes is vital for mark-release-recapture and many laboratory studies, but their small size precludes the use of methods that are available for larger animals such as unique identifier tags and radio devices. Fluorescent dust is the most commonly used method to distinguish released individuals from the wild population. Numerous colours and combinations can be used, however, dust sometimes affects longevity and behaviour so alternatives that do not have these effects would contribute substantially. Rhodamine B has previously been demonstrated to be useful for marking adultAedes aegyptimales when added to the sugar meal. Unlike dust, this also marked the seminal fluid making it possible to detect matings by marked males in the spermatheca of females. Here, marking ofAnopheles gambiaesensu stricto with rhodamine B and uranine was performed to estimate their potential contribution. | https://doi.org/10.1186/s12936-020-03306-5 | Lower high school; Upper high school |
Biology Articles | How can we track mosquitoes And why | Mosquitoes arent just annoying, they can carry deadly diseases as well. The main way to control these diseases is by controlling mosquito populations. In order to do that, we have to study the ecology of these populations; we have to track the mosquitoes. Mark-release-recapture (MRR) is a great method to estimate the populations size and other information. Mosquito MRR experiments, however, have some limitations as these insects are really small and have short lives. We present mathematical models that address these limitations. Our results indicate a good estimation of the population abundance (number of mosquitoes in a given area). | Background Experiments involving mosquito mark-release-recapture (MRR) design are helpful to determine abundance, survival and even recruitment of mosquito populations in the field. Obstacles in mosquito MRR protocols include marking limitations due to small individual size, short lifespan, low efficiency in capturing devices such as traps, and individual removal upon capture. These limitations usually make MRR analysis restricted to only abundance estimation or a combination of abundance and survivorship, and often generate a great degree of uncertainty about the estimations. Methodology/Principal findings We present a set of Bayesian biodemographic models designed to fit data from most common mosquito recapture experiments. Using both field data and simulations, we consider model features such as capture efficiency, survival rates, removal of individuals due to capturing, and collection of pupae. These models permit estimation of abundance, survivorship of both marked and unmarked mosquitoes, if different, and recruitment rate. We analyze the accuracy of estimates by varying the number of released individuals, abundance, survivorship, and capture efficiency in multiple simulations. These methods can stand capture efficiencies as low as usually reported but their accuracy depends on the number of released mosquitoes, abundance and survivorship. We also show that gathering pupal counts allows estimating differences in survivorship between released mosquitoes and the unmarked population. Conclusion/Significance These models are important both to reduce uncertainty in evaluating MMR experiments and also to help planning future MRR studies. | https://doi.org/10.1371/journal.pntd.0005682 | Lower high school; Upper high school |
Biology Articles; Health-And-Medicine Articles | How can we use genetic engineering to get rid of malaria for good | Nobody likes the buzzing sound or itchy bite of mosquitoes. What if we used genetic engineering? Here we modified But mosquito bites (only females bite, by the way!) are not the genetic makeup of Anopheles gambiae mosquitoes (the just irritating: they can carry and spread deadly diseases main carriers of malaria). The mutation prevented females such as malaria, dengue, yellow fever and many more. Every from biting and laying eggs. It spread through our caged year, millions of people die from mosquito-borne diseases and populations quickly and drove them extinct. Our results pave most of them are young children. There are ways to get rid the way for lowering mosquito populations in the wild and of mosquitoes and prevent such diseases, but they are not as getting rid of malaria in the future. effective as we would like. | In the human malaria vectorAnopheles gambiae, the genedoublesex(Agdsx) encodes two alternatively spliced transcripts,dsx-female(AgdsxF) anddsx-male(AgdsxM), that control differentiation of the two sexes. The female transcript, unlike the male, contains an exon (exon 5) whose sequence is highly conserved in allAnophelesmosquitoes so far analyzed. We found that CRISPRCas9-targeted disruption of the intron 4exon 5 boundary aimed at blocking the formation of functional AgdsxF did not affect male development or fertility, whereas females homozygous for the disrupted allele showed an intersex phenotype and complete sterility. A CRISPRCas9 gene drive construct targeting this same sequence spread rapidly in caged mosquitoes, reaching 100% prevalence within 711 generations while progressively reducing egg production to the point of total population collapse. Owing to functional constraint of the target sequence, no selection of alleles resistant to the gene drive occurred in these laboratory experiments. Cas9-resistant variants arose in each generation at the target site but did not block the spread of the drive. | https://doi.org/10.1038/nbt.4245 | Lower high school; Upper high school |
Biology Articles; Health-And-Medicine Articles | How did organoids help scientists understand COVID-19 | Have you ever wondered how scientists know how a virus affects the human body? Or how they develop medicines and vaccines to reduce the impact of viruses like the one that causes COVID-19? The answer is organoids! These miniature models of human organs are grown in the laboratory. Scientists use organoids to determine how a virus attacks the body and identify possible treatments for the virus. We conducted a literature review of the organoids used in COVID-19 research. We found that COVID-19 research used many different types of organoids. We also learned how scientists created these organoids and what they taught us about the SARS-CoV-2 virus. We identified ways to improve this new method of disease research in the future. | Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is one of the deadliest pandemics in history. SARS-CoV-2 not only infects the respiratory tract, but also causes damage to many organs. Organoids, which can self-renew and recapitulate the various physiology of different organs, serve as powerful platforms to model COVID-19. In this Perspective, we overview the current effort to apply both human pluripotent stem cell-derived organoids and adult organoids to study SARS-CoV-2 tropism, host response and immune cell-mediated host damage, and perform drug discovery and vaccine development. We summarize the technologies used in organoid-based COVID-19 research, discuss the remaining challenges and provide future perspectives in the application of organoid models to study SARS-CoV-2 and future emerging viruses. | https://www.nature.com/articles/s41592-022-01453-y# | Elementary school; Lower high school; Middle school |
Biology Articles; Food-And-Agriculture Articles | How do bacteria help plants | All plants need nitrogen to grow. Farmers use chemical fertilizers to add nitrogen to the soil. But this creates a lot of problems for the environment. So, scientists have been working on alternative ways to get nitrogen to their plants. We found a way to edit the DNA of rice plants so that they produce a compound that helps the formation of bacterial biofilms in the soil. These bacterial biofilms are very important to plants. They help them to absorb more nitrogen from the air. The edited rice plants in our experiment did grow better! | Improving biological nitrogen fixation (BNF) in cereal crops is a long-sought objective; however, no successful modification of cereal crops showing increased BNF has been reported. Here, we described a novel approach in which rice plants were modified to increase the production of compounds that stimulated biofilm formation in soil diazotrophic bacteria, promoted bacterial colonization of plant tissues and improved BNF with increased grain yield at limiting soil nitrogen contents. We first used a chemical screening to identify plant-produced compounds that induced biofilm formation in nitrogen-fixing bacteria and demonstrated that apigenin and other flavones induced BNF. We then used CRISPR-based gene editing targeting apigenin breakdown in rice, increasing plant apigenin contents and apigenin root exudation. When grown at limiting soil nitrogen conditions, modified rice plants displayed increased grain yield. Biofilm production also modified the root microbiome structure, favouring the enrichment of diazotrophic bacteria recruitment. Our results support the manipulation of the flavone biosynthetic pathway as a feasible strategy for the induction of biological nitrogen fixation in cereals and a reduction in the use of inorganic nitrogen fertilizers. | https://onlinelibrary.wiley.com/doi/full/10.1111/pbi.13894 | Lower high school |
Biology Articles; Health-And-Medicine Articles | How do bacteria in the gut control the brain | Bacteria are everywhere including our bodies. This is not a of mice which we treated with bifidobacteria only, and bad thing as they help us in many ways. Many studies show compared it to the behavior of mice without any bacteria that gut bacteria have an impact on behavior as well. During and mice that had normal mouse gut bacteria. The germ- the first few months after birth the brain actively develops. At free mice showed many important behavioral differences the same time, bacteria enter from the diet and environment when compared to mice with normal bacteria, and the mice and multiply in the infants gut. As Bifidobacterium species that had only bifidobacteria behaved similarly to the normal (bifidobacteria) are the most common bacteria in the infants mice demonstrating how important these bacteria are. The gut, we wanted to see if these bacteria play a role in the sex of the rodents also played an important role in whether development of brain functions. We examined the behavior bifidobacteria could change their behavior. | Accumulating studies have defined a role for the intestinal microbiota in modulation of host behavior. Research using gnotobiotic mice emphasizes that early microbial colonization with a complex microbiota (conventionalization) can rescue some of the behavioral abnormalities observed in mice that grow to adulthood completely devoid of bacteria (germ-free mice). However, the human infant and adult microbiomes vary greatly, and effects of the neonatal microbiome on neurodevelopment are currently not well understood. Microbe-mediated modulation of neural circuit patterning in the brain during neurodevelopment may have significant long-term implications that we are only beginning to appreciate. Modulation of the host central nervous system by the early-life microbiota is predicted to have pervasive and lasting effects on brain function and behavior. We sought to replicate this early microbe-host interaction by colonizing gnotobiotic mice at the neonatal stage with a simplified model of the human infant gut microbiota. This model consortium consisted of four infant-type Bifidobacterium species known to be commensal members of the human infant microbiota present in high abundance during postnatal development. Germ-free mice and mice neonatally-colonized with a complex, conventional murine microbiota were used for comparison. Motor and non-motor behaviors of the mice were tested at 67 weeks of age, and colonization patterns were characterized by 16S ribosomal RNA gene sequencing. Adult germ-free mice were observed to have abnormal memory, sociability, anxiety-like behaviors, and motor performance. Conventionalization at the neonatal stage rescued these behavioral abnormalities, and mice colonized with Bifidobacterium spp. also exhibited important behavioral differences relative to the germ-free controls. The ability of Bifidobacterium spp. to improve the recognition memory of both male and female germ-free mice was a prominent finding. Together, these data demonstrate that the early-life gut microbiome, and human infant-type Bifidobacterium species, affect adult behavior in a strongly sex-dependent manner, and can selectively recapitulate the results observed when mice are colonized with a complex microbiota. | http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0196510 | Lower high school; Upper high school |
Biology Articles; Chemistry Articles; Health-And-Medicine Articles; Pollution Articles | How do chemicals affect animals and their kids | Our endocrine system is very bossy. It controls many things in our bodies, like growth or mood. Sadly, there are chemicals that interfere with this important system. Endocrine-disrupting chemicals are all around us. Their negative effects can even pass on to future generations. How does this happen? We reviewed many articles on endocrine disruptors and their effects on various animals. These chemicals have negative effects on fish, frogs, birds and mammals. Sometimes the effects pass on to many generations. However, the mechanism for this transfer is not genetic but most likely epigenetic. | A wide range of chemicals have been identified as endocrine disrupting chemicals (EDCs) in vertebrate species. Most studies of EDCs have focused on exposure of both male and female adults to these chemicals; however, there is clear evidence that EDCs have dramatic effects when mature or developing gametes are exposed, and consequently are associated with in multigenerational and transgenerational effects. Several publications have reviewed such actions of EDCs in subgroups of species, e.g., fish or rodents. In this review, we take a holistic approach synthesizing knowledge of the effects of EDCs across vertebrate species, including fish, anurans, birds, and mammals, and discuss the potential mechanism(s) mediating such multi- and transgenerational effects. We also propose a series of recommendations aimed at moving the field forward in a structured and coherent manner. | https://www.sciencedirect.com/science/article/pii/S001393512101358X | Middle school |
Biology Articles | How do glassfrogs become transparent | Glassfrogs earned their name not because they are fragile, but because they are see-through! These tropical frogs have transparent skin and muscles. When sleeping on green leaves, their bodies are almost impossible to see. This form of camouflage is rare. Most animals have colorful red blood cells that would be visible under transparent skin and give them away to predators. We used a special scanner to figure out how glassfrogs overcome this challenge. We discovered that these frogs are more transparent when they sleep than when they are active. They do this by hiding most of their red blood cells in their livers during sleep! This makes them nearly transparent to predators. Our results help explain how glassfrogs can manage this unusual kind of camouflage. This finding may also help doctors treat medical conditions in humans. | Transparency in animals is a complex form of camouflage involving mechanisms that reduce light scattering and absorption throughout the organism. In vertebrates, attaining transparency is difficult because their circulatory system is full of red blood cells (RBCs) that strongly attenuate light. Here, we document how glassfrogs overcome this challenge by concealing these cells from view. Using photoacoustic imaging to track RBCs in vivo, we show that resting glassfrogs increase transparency two- to threefold by removing ~89% of their RBCs from circulation and packing them within their liver. Vertebrate transparency thus requires both see-through tissues and active mechanisms that clear respiratory pigments from these tissues. Furthermore, glassfrogs ability to regulate the location, density, and packing of RBCs without clotting offers insight in metabolic, hemodynamic, and blood-clot research. | https://www.science.org/doi/10.1126/science.abl6620 | Middle school |
Biology Articles; Health-And-Medicine Articles | How do microbes shape fruit fly fitness | Did you know that you are never alone in your own body? Like with all animals, your body provides a home for a community of microbes, making it a microbiome. Microbiomes impact their hosts ability to survive, age, and produce offspring. An important question is how each bacterial species affects our health. But with hundreds of species in our gut, it is difficult to single out any one in particular. Any species could have a direct effect on us, or the effects could be due to interactions between species. How do we unravel this complexity? To explore how microbes impact their host, we looked at the Drosophila melanogaster fruit fly. It has only five bacterial species in its gut making it much simpler to study than a human. We examined a fly without bacteria and with every possible combination of the five bacterial species. We found that the species present in the gut and the interactions between them both affect the fly. This finding suggests that humans might also be impacted by the complex microbe interactions in their gut. | Significance All animals have associated microbial communities called microbiomes that influence the physiology and fitness of their host. It is unclear to what extent individual microbial species versus interactions between them influence the host. Here, we mapped all possible interactions between individual species of bacteria against Drosophila melanogaster fruit fly fitness traits. Our approach revealed that the same bacterial interactions that shape microbiome abundances also shape host fitness traits. The fitness traits of lifespan and fecundity showed a life history tradeoff, where equal total fitness can be gotten by either high fecundity over a short life or low fecundity over a long life. The microbiome interactions are as important as the individual species in shaping these fundamental aspects of fly physiology. Gut bacteria can affect key aspects of host fitness, such as development, fecundity, and lifespan, while the host, in turn, shapes the gut microbiome. However, it is unclear to what extent individual species versus community interactions within the microbiome are linked to host fitness. Here, we combinatorially dissect the natural microbiome of Drosophila melanogaster and reveal that interactions between bacteria shape host fitness through life history tradeoffs. Empirically, we made germ-free flies colonized with each possible combination of the five core species of fly gut bacteria. We measured the resulting bacterial community abundances and fly fitness traits, including development, reproduction, and lifespan. The fly gut promoted bacterial diversity, which, in turn, accelerated development, reproduction, and aging: Flies that reproduced more died sooner. From these measurements, we calculated the impact of bacterial interactions on fly fitness by adapting the mathematics of genetic epistasis to the microbiome. Development and fecundity converged with higher diversity, suggesting minimal dependence on interactions. However, host lifespan and microbiome abundances were highly dependent on interactions between bacterial species. Higher-order interactions (involving three, four, and five species) occurred in 1344% of possible cases depending on the trait, with the same interactions affecting multiple traits, a reflection of the life history tradeoff. Overall, we found these interactions were frequently context-dependent and often had the same magnitude as individual species themselves, indicating that the interactions can be as important as the individual species in gut microbiomes. | https://doi.org/10.1073/pnas.1809349115 | Lower high school |
Biology Articles | How do nematodes learn to find a host | Parasites live in, or on, other organisms. All parasites want wanted to see if past experience with some volatiles changes to find and successfully infect a host so that they can the infection behavior of nematodes. We treated the host live and reproduce. Its hard and risky for an individual environment with different concentrations of two volatiles parasite to infect a host a group attack is a safer option. known to have an influence on nematodes and observed Insect-infecting nematodes use this strategy by following the infection success. Our experiments showed us that the environmental signals, such as plant volatiles (scents). We nematodes past experience alters their infection behavior. | Nematode parasites rely on successful host infection to perpetuate their species. Infection by individual nematode parasites can be risky, however; any one individual could be killed by the hosts immune response. Here we use a model system to show that environmental cues and parasite past experience can be used by entomopathogenic nematodes to reduce individual risk of infection. Past parasite experience can more than double the infective virulence (number of host invaders) of a given cohort of entomopathogenic nematode parasites. This plasticity in individual parasite risk-taking and associated infection can be used to manage infection of parasitic nematodes: enhancing biological control with entomopathogenic nematodes and developing behavioral and chemical strategies to reduce infection by vertebrate and plant parasitic nematodes. | https://doi.org/10.1371/journal.pone.0205804 | Lower high school; Upper high school |
Biology Articles | How do ravens thinking skills compare with apes | Ravens behave in ways that suggest they are really know more about ravens intelligence, and we wanted to be smart. Most scientists studying animal intelligence focus able to compare ravens and great apes. So, we changed the on monkeys and apes like macaques and chimpanzees. set of puzzles to make sure they could be solved by a bird One group of scientists made a set of puzzles that tested using a beak instead of fingers. We found that ravens did primates physical and social thinking skills. We wanted to just as well as the apes on almost all of the puzzles! | Human children show unique cognitive skills for dealing with the social world but their cognitive performance is paralleled by great apes in many tasks dealing with the physical world. Recent studies suggested that members of a songbird familycorvidsalso evolved complex cognitive skills but a detailed understanding of the full scope of their cognition was, until now, not existent. Furthermore, relatively little is known about their cognitive development. Here, we conducted the first systematic, quantitative large-scale assessment of physical and social cognitive performance of common ravens with a special focus on development. To do so, we fine-tuned one of the most comprehensive experimental test-batteries, the Primate Cognition Test Battery (PCTB), to raven features enabling also a direct, quantitative comparison with thecognitive performance of two great ape species. Full-blown cognitive skills were already present at the age of four months with subadult ravens cognitive performance appearing very similar to that of adult apes in tasks of physical (quantities, and causality) and social cognition (social learning, communication, and theory of mind). These unprecedented findings strengthen recent assessments of ravens general intelligence, and aid to the growing evidence that the lack of a specific cortical architecture does not hinder advanced cognitive skills. Difficulties in certain cognitive scales further emphasize the quest to develop comparative test batteries that tap into true species rather than human specific cognitive skills, and suggest that socialization of test individuals may play a crucial role. We conclude to pay more attention to the impact of personality on cognitive output, and a currently neglected topic in Animal Cognitionthe linkage between ontogeny and cognitive performance. | https://doi.org/10.1038/s41598-020-77060-8 | Lower high school; Middle school |
Biology Articles | How do some fungi turn insects into zombies | Did you know that certain fungi can turn insects into zombies,just like in the movies? These "zombie-making" fungi control the insects behavior and make their hosts do strange things like walking a long way, climbing tall plants, and hanging onto high surfaces. This is so the fungi can make their infectious spores spread further. There are many types of zombie-making fungi, and most have evolved independently. Yet they change the insects behavior in a similar way. How do they do this and why is it so common? We reviewed previous studies on zombie-making fungi to search for an answer. These fungi use both mechanical and chemical processes to control their hosts. And while the changed behavior is very similar, the ways they achieve it vary greatly among the different species of zombie-making fungi. Each one has its own unique way of manipulating insects to change the same behaviors! We believe these same behaviors are changed by all these different fungal species because these manipulations are the best way to infect as many other hosts as possible. | Transmission is a crucial step in all pathogen life cycles. As such, certain species have evolved complex traits that increase their chances to find and invade new hosts. Fungal species that hijack insect behaviors are evident examples. Many of these zombie-making entomopathogens cause their hosts to exhibit heightened activity, seek out elevated positions, and display body postures that promote spore dispersal, all with specific circadian timing. Answering how fungal entomopathogens manipulate their hosts will increase our understanding of molecular aspects underlying fungus-insect interactions, pathogen-host coevolution, and the regulation of animal behavior. It may also lead to the discovery of novel bioactive compounds, given that the fungi involved have traditionally been understudied. This minireview summarizes and discusses recent work on zombie-making fungi of the orders Hypocreales and Entomophthorales that has resulted in hypotheses regarding the mechanisms that drive fungal manipulation of insect behavior. We discuss mechanical processes, host chemical signaling pathways, and fungal secreted effectors proposed to be involved in establishing pathogen-adaptive behaviors. Additionally, we touch on effectors possible modes of action and how the convergent evolution of host manipulation could have given rise to the many parallels in observed behaviors across fungus-insect systems and beyond. However, the hypothesized mechanisms of behavior manipulation have yet to be proven. We, therefore, also suggest avenues of research that would move the field toward a more quantitative future. | https://journals.asm.org/doi/10.1128/mBio.01872-21 | Elementary school; Lower high school; Middle school; Upper high school |
Biology Articles | How do termites divide the work | What do you know about termites? Perhaps youve We wanted to identify the specific individuals who are heard that some termites can infest your home. But the most active during the start and expansion of tunnel there are many different species out there. For example, construction. We monitored five groups of termites for subterranean termites make tunnels in the soil to look for three days and found that it was usually three individuals food. Like other social insects, termites divide their tasks who do most of the work all the time. We believe that these by assigning them to different groups. So how do they top busy workers are also responsible for the organization organize the tunnel construction? of the tunnel network. | This study provided a detailed analysis of the tunneling behavior of 30 marked individuals by examining the role of each individual in tunnel excavation on three consecutive days. The objective of this study was to identify the specific individuals that were the most active in the initiation of a new tunnel on the first day in order to determine if these specific individuals continued to play a key role in tunnel excavation as the tunnel expanded on the second day. In addition, this study examined the behavior of the same group of individuals in the initiation of a new tunnel on the third day. Overall, there was an average of three individuals transporting > 20 loads of sand, 13 individuals transporting between 1 and 20 loads, and 14 individuals that did not transport any loads during each 2-h observation period. Top excavators during tunnel initiation were significantly more likely to continue to be top excavators during tunnel expansion than other individuals. These top excavators were also more likely to perform the most work in the excavation of a new tunnel on the third day. These results demonstrate that specific individuals remain highly active for at least 3 days which provides further evidence that top excavators act as organizers in determining the orientation and branching patterns in the tunneling networks of C. formosanus. | https://www.sciencedirect.com/science/article/pii/S122686151500093X | Lower high school; Middle school |
Biology Articles | How do viruses trick their hosts into feeding them | Scientists estimate that mammals can be infected with more than 300 thousand virus species! All organisms need energy, but simple microorganisms like viruses cannot produce their own energy. Instead, viruses survive by redirecting energy from a host organism to their own benefit. Normally, viruses survive by infecting cells and forcing them to produce more viruses. However, we have discovered a new class of viruses that redirect energy in a unique and fascinating way! These viruses are able to trick their host organism by producing their own version of insulin, called viral insulin. This viral insulin is like a wolf in sheeps clothing because the host organism cannot tell the difference between its own insulin and the viral insulin. | Lymphocystis disease virus-1 (LCDV-1) and several other Iridoviridae encode viral insulin/IGF-1 like peptides (VILPs) with high homology to human insulin and IGFs. Here we show that while single-chain (sc) and double-chain (dc) LCDV1-VILPs have very low affinity for the insulin receptor, scLCDV1-VILP has high affinity for IGF1R where it can antagonize human IGF-1 signaling, without altering insulin signaling. Consequently, scLCDV1-VILP inhibits IGF-1 induced cell proliferation and growth hormone/IGF-1 induced growth of mice in vivo. Cryo-electron microscopy reveals that scLCDV1-VILP engages IGF1R in a unique manner, inducing changes in IGF1R conformation that led to separation, rather than juxtaposition, of the transmembrane segments and hence inactivation of the receptor. Thus, scLCDV1-VILP is a natural peptide with specific antagonist properties on IGF1R signaling and may provide a new tool to guide development of hormonal analogues to treat cancers or metabolic disorders sensitive to IGF-1 without affecting glucose metabolism. | https://www.nature.com/articles/s41467-022-34391-6 | Lower high school; Middle school |
Biology Articles; Chemistry Articles; Health-And-Medicine Articles | How does a plant make an antimalarial medicine | If you think using plants to cure disease is a thing of the converts another molecule (DHAA) into artemisinin. But past, think again! Today, many medicines in drugstores no one understood how! Here, we solved this biology contain chemicals from medicinal plants. An herb called problem using chemistry. We tagged DHAA molecules by sweet wormwood (Artemisia annua) is one of them. Sweet developing a set of chemical reactions. Using technology, wormwood is a very effective medicine to treat malaria, we then monitored the conversion of DHAA to artemisinin. the worlds deadliest disease. The active ingredient, We found this conversion happens spontaneously, without artemisinin, kills malaria-causing parasites faster than any enzymes. Also, it occurs faster in the presence of light. Our other medicine. We wanted to understand exactly how this understanding of artemisinin formation can help us develop plant makes artemisinin. We knew that sweet wormwood better malaria medicines in laboratories. | Dihydroartemisinic acid is the biosynthetic precursor to artemisinin, the endoperoxide-containing natural product used to treat malaria. The conversion of dihydroartemisinic acid to artemisinin is a cascade reaction that involves CC bond cleavage, hydroperoxide incorporation, and polycyclization to form the endoperoxide. Whether or not this reaction is enzymatically controlled has been controversial. A method was developed to quantify the nonenzymatic conversion of dihydroartemisinic acid to artemisinin using LC-MS. A seven-step synthesis of 3,3-dideuterodihydroartemisinic acid (23) was accomplished beginning with dihydroartemisinic acid (1). The nonenzymatic rates of formation of 3,3-dideuteroartemisinin (24) from 3,3-dideuterodihydroartemisinic acid (23) were 1400 ng/day with light and 32 ng/day without light. Moreover, an unexpected formation of nondeuterated artemisinin (3) from 3,3-dideuterodihydroartemisinic acid (23) was detected in both the presence and absence of light. This formation of nondeuterated artemisinin (3) from its dideuterated precursor (23) suggests an alternative mechanistic pathway that operates independent of light to form artemisinin, involving the loss of the two C-3 deuterium atoms. | https://pubs.acs.org/doi/full/10.1021/acs.jnatprod.9b00686 | Upper high school |
Biology Articles; Health-And-Medicine Articles | How does pregnancy change mothers behavior | Pregnancy changes a lot of things in a mother: the body goes through many transformations trying to adapt to the needs of the baby. The mothers behavior changes as well, as she has to care for her newborn. There is some indirect evidence that the baby (through its genes) could instruct the mothers brain and alter her behavior even before it is born. But is this really true? We have previously found a gene that controls the number of hormones produced by the placenta, an organ that connects the developing embryo to the mother. To test if the embryos could affect the mothers behavior, we conducted a series of experiments on mice who were pregnant with embryos expressing different doses of this gene. Indeed, mothers exposed to higher doses of the gene preferred nest-building over baby nursing. | In mammals, mothers are the primary caregiver, programmed, in part, by hormones produced during pregnancy. High-quality maternal care is essential for the survival and lifelong health of offspring. We previously showed that the paternally silenced imprinted gene pleckstrin homology-like domain family A member 2 (Phlda2) functions to negatively regulate a single lineage in the mouse placenta called the spongiotrophoblast, a major source of hormones in pregnancy. Consequently, the offsprings Phlda2 gene dosage may influence the quality of care provided by the mother. Here, we show that wild-type (WT) female mice exposed to offspring with three different doses of the maternally expressed Phlda2 genetwo active alleles, one active allele (the extant state), and loss of functionshow changes in the maternal hypothalamus and hippocampus during pregnancy, regions important for maternal-care behaviour. After birth, WT dams exposed in utero to offspring with the highest Phlda2 dose exhibit decreased nursing and grooming of pups and increased focus on nest building. Conversely, paternalised dams, exposed to the lowest Phlda2 dose, showed increased nurturing of their pups, increased self-directed behaviour, and a decreased focus on nest building, behaviour that was robustly maintained in the absence of genetically modified pups. This work raises the intriguing possibility that imprinting of Phlda2 contributed to increased maternal care during the evolution of mammals. | https://doi.org/10.1371/journal.pbio.2006599 | Lower high school; Upper high school |
Biology Articles; Health-And-Medicine Articles | How is Cannabis connected to leishmaniasis infections | When you think about dangerous animals, what comes to term organ damage or even death. This makes preventing mind? Spiders? Killer bees? Think smaller the most deadly new infections very important. insects are mosquitoes and flies! Pathogens transmitted by This is why we wanted to know what exactly sand flies eat. mosquito bites kill half a million people every year. Sand fly females suck blood but both males and females Phlebotomine sand flies may not look very scary. Theyre also feed on plant sap. We collected five species of sand only millimeters long! But they infect more than a million flies from five different countries. We were surprised in people with Leishmania parasites every year. Early diagnosis all but one site sand flies fed on a plant which is illegal for and treatment can cure leishmaniasis infections. But it can farmers to cultivate ...Cannabis sativa! | Blood-sucking phlebotomine sand flies (Diptera: Psychodidae) transmit leishmaniasis as well as arboviral diseases and bartonellosis. Sand fly females become infected with Leishmania parasites and transmit them while imbibing vertebrates blood, required as a source of protein for maturation of eggs. In addition, both females and males consume plant-derived sugar meals as a source of energy. Plant meals may comprise sugary solutions such as nectar or honeydew (secreted by plant-sucking homopteran insects), as well as phloem sap that sand flies obtain by piercing leaves and stems with their needle-like mouthparts. Hence, the structure of plant communities can influence the distribution and epidemiology of leishmaniasis. We designed a next-generation sequencing (NGS)based assay for determining the source of sand fly plant meals, based upon the chloroplast DNA gene ribulose bisphosphate carboxylase large chain (rbcL). Here, we report on the predilection of several sand fly species, vectors of leishmaniasis in different parts of the world, for feeding on Cannabis sativa. We infer this preference based on the substantial percentage of sand flies that had fed on C. sativa plants despite the apparent absence of these plants from most of the field sites. We discuss the conceivable implications of the affinity of sand flies for C. sativa on their vectorial capacity for Leishmania and the putative exploitation of their attraction to C. sativa for the control of sand fly-borne diseases. | https://www.pnas.org/content/115/46/11790 | Lower high school |
Biology Articles; Paleoscience Articles | What can ancient DNA tell us about Stone Age people | Archaeologists digging in Bacho Kiro Cave in where their descendants ended up. Surprisingly, Bulgaria found bones from people who lived , even though the bones were found in Europe, their years ago. This period is known as the early Upper DNA had more in common with people from East Paleolithic. It was an exciting time for human Asia and Native Americans. We also found that all evolution as humans took a big jump forward in art the individuals whose remains were found in Bacho and technology. Its also a time when Neanderthals Kiro Cave had Neanderthal ancestors only a few were still around. generations back. That means that not only did Stone Age humans and Neanderthals know about We wanted to know what these peoples DNA could each other, they sometimes had children together. tell us about where their ancestors came from and | Modern humans appeared in Europe by at least 45,000 years ago1,2,3,4,5, but the extent of their interactions with Neanderthals, who disappeared by about 40,000 years ago6, and their relationship to the broader expansion of modern humans outside Africa are poorly understood. Here we present genome-wide data from three individuals dated to between 45,930 and 42,580 years ago from Bacho Kiro Cave, Bulgaria1,2. They are the earliest Late Pleistocene modern humans known to have been recovered in Europe so far, and were found in association with an Initial Upper Palaeolithic artefact assemblage. Unlike two previously studied individuals of similar ages from Romania7and Siberia8who did not contribute detectably to later populations, these individuals are more closely related to present-day and ancient populations in East Asia and the Americas than to later west Eurasian populations. This indicates that they belonged to a modern human migration into Europe that was not previously known from the genetic record, and provides evidence that there was at least some continuity between the earliest modern humans in Europe and later people in Eurasia. Moreover, we find that all three individuals had Neanderthal ancestors a few generations back in their family history, confirming that the first European modern humans mixed with Neanderthals and suggesting that such mixing could have been common. | https://www.nature.com/articles/s41586-021-03335-3 | Lower high school |
Biology Articles; Chemistry Articles; Pollution Articles | What can tree frogs in Chernobyl tell us about radiation | Have you ever heard of Chernobyl? It was a nuclear power plant that released large amounts of radiation into the environment after an accident. While the people nearby left the area, the wildlife remained. Many plants and animals died because of the high levels of radiation. But others, such as tree frogs, adapted. We collected tree frogs from different areas surrounding the Chernobyl power plant. We analyzed their skin coloration. We found that the frogs closer to the power plant had darker skin coloration. Thats because they have higher levels of melanin. Melanin is known to protect organisms from radiation. We think that darker colored frogs better survived the higher levels of radiation closer to the power plant. | Human actions are altering ecosystems worldwide. Among human-released pollutants, ionizing radiation arises as a rare but potentially devastating threat to natural systems. The Chornobyl accident (1986) represents the largest release of radioactive material to the environment. Our aim was to examine how exposure to radiation from the Chornobyl accident influences dorsal skin coloration of Eastern tree frog (Hyla orientalis) males sampled across a wide gradient of radioactive contamination in northern Ukraine. We assessed the relationship between skin frog coloration (which can act as a protective mechanism against ionizing radiation), radiation conditions and oxidative stress levels. Skin coloration was darker in localities closest to areas with high radiation levels at the time of the accident, whereas current radiation levels seemed not to influence skin coloration in Chornobyl tree frogs. Tree frogs living within the Chornobyl Exclusion Zone had a remarkably darker dorsal skin coloration than frogs from outside the Zone. The maintenance of dark skin coloration was not linked to physiological costs in terms of frog body condition or oxidative status, and we did not detect short-term changes in frog coloration. Dark coloration is known to protect against different sources of radiation by neutralizing free radicals and reducing DNA damage, and, particularly melanin pigmentation has been proposed as a buffering mechanism against ionizing radiation. Our results suggest that exposure to high levels of ionizing radiation, likely at the time of the accident, may have been selected for darker coloration in Chornobyl tree frogs. Further studies are needed to determine the underlying mechanisms and evolutionary consequences of the patterns found here. | https://onlinelibrary.wiley.com/doi/full/10.1111/eva.13476 | Lower high school; Middle school |
Biology Articles | What can we learn about aging from naked mole-rats | Did you know that naked mole-rats dont age the same way humans and other mammals do? These incredible rodents dont seem to age physically and they are resistant to age-related diseases. Thats why they can live over 30 years! Scientists are trying to understand how aging works in naked mole-rats so that they can better understand aging in humans. We conducted a DNA analysis of naked mole-rat tissue to find out if their DNA shows signs of aging. We discovered that naked mole-rats do age on a molecular level like other mammals. Identifying where the DNA changed in naked mole-rats allowed us to predict what effects these changes might have on the body. We also found that members of a naked mole-rat community age faster than their queen. | Naked mole rats (NMRs) live an exceptionally long life, appear not to exhibit age-related decline in physiological capacity and are resistant to age-related diseases. However, it has been unknown whether NMRs also evade aging according to a primary hallmark of aging: epigenetic changes. To address this question, we profiledn=?385 samples from 11 tissue types at loci that are highly conserved between mammalian species using a custom array (HorvathMammalMethylChip40). We observed strong epigenetic aging effects and developed seven highly accurate epigenetic clocks for several tissues (pan-tissue, blood, kidney, liver, skin clocks) and two dual-species (humanNMR) clocks. The skin clock correctly estimated induced pluripotent stem cells derived from NMR fibroblasts to be of prenatal age. The NMR epigenetic clocks revealed that breeding NMR queens age more slowly than nonbreeders, a feature that is also observed in some eusocial insects. Our results show that despite a phenotype of negligible senescence, the NMR ages epigenetically. | https://www.nature.com/articles/s43587-021-00152-1 | Elementary school; Middle school |
Biology Articles | What causes lizards brains to change size | Imagine you owned a patch of land, but couldnt put up territory, he has to be able to remember what belongs to any fences. How would you remember what was yours and him and what doesnt! Otherwise he will risk getting into what belonged to your neighbor? lots of fights with other territorial male neighbors. Many animal species protect areas of land, which we call A special part of the brain processes the memory of spaces their territories. By keeping competitors off their land, and locations. We ran an experiment on lizards to see what a territorial male is able to mate with any females that caused this part of the brain to change size. The results live there. As well as being strong enough to defend his were not what we expected! | Variation in an animal's spatial environment can induce variation in the hippocampus, an area of the brain involved in spatial cognitive processing. Specifically, increased spatial area use is correlated with increased hippocampal attributes, such as volume and neurogenesis. In the side-blotched lizard (Uta stansburiana), males demonstrate alternative reproductive tactics and are either territorialdefending large, clearly defined spatial boundariesor non-territorialtraversing home ranges that are smaller than the territorial males' territories. Our previous work demonstrated cortical volume (reptilian hippocampal homolog) correlates with these spatial niches. We found that territorial holders have larger medial cortices than non-territory holders, yet these differences in the neural architecture demonstrated some degree of plasticity as well. Although we have demonstrated a link among territoriality, spatial use, and brain plasticity, the mechanisms that underlie this relationship are unclear. Previous studies found that higher testosterone levels can induce increased use of the spatial area and can cause an upregulation in hippocampal attributes. Thus, testosterone may be the mechanistic link between spatial area use and the brain. What remains unclear, however, is if testosterone can affect the cortices independent of spatial experiences and whether testosterone differentially interacts with territorial status to produce the resultant cortical phenotype. In this study, we compared neurogenesis as measured by the total number of doublecortin-positive cells and cortical volume between territorial and non-territorial males supplemented with testosterone. We found no significant differences in the number of doublecortin-positive cells or cortical volume among control territorial, control non-territorial, and testosterone-supplemented non-territorial males, while testosterone-supplemented territorial males had smaller medial cortices containing fewer doublecortin-positive cells. These results demonstrate that testosterone can modulate medial cortical attributes outside of differential spatial processing experiences but that territorial males appear to be more sensitive to alterations in testosterone levels compared with non-territorial males. | https://doi.org/10.3389/fnins.2017.00097 | Lower high school; Upper high school |
Biology Articles | What does hummingbird coloration tell us about competition | Have you ever wondered why animals look different from they are left alone to eat. We wanted to know if fancy females each other? Think of a rooster compared to a hen. Usually just look fancy. Or are they actually better competitors? theres a reason those differences have evolved. We found that fancy females were more like other females. We looked at hummingbirds to learn more about their colors. Fancy females are mimicking male color patterns. This is the Some females have a fancy color pattern like the males do. first time weve seen females mimicking males to get the The males are aggressive. Fancy females look like males, so advantages of a dominant form. | Female-limited polymorphisms, where females have multiple forms but males have only one, have been described in a variety of animals, yet are difficult to explain because selection typically is expected to decrease rather than maintain diversity. In the white-necked jacobin (Florisuga mellivora), all males and approximately 20% of females express an ornamented plumage type (androchromic), while other females are non-ornamented (heterochromic). Androchrome females benefit from reduced social harassment, but it remains unclear why both morphs persist. Female morphs may represent balanced alternative behavioural strategies, but an alternative hypothesis is that androchrome females are mimicking males. Here, we test a critical prediction of these hypotheses by measuring morphological, physiological and behavioural traits that relate to resource-holding potential (RHP), or competitive ability. In all these traits, we find little difference between female types, but higher RHP in males. These results, together with previous findings in this species, indicate that androchrome females increase access to food resources through mimicry of more aggressive males. Importantly, the mimicry hypothesis provides a clear theoretical pathway for polymorphism maintenance through frequency-dependent selection. Social dominance mimicry, long suspected to operate between species, can therefore also operate within species, leading to polymorphism and perhaps similarities between sexes more generally. | https://royalsocietypublishing.org/doi/full/10.1098/rspb.2022.0332 | Elementary school; Lower high school; Middle school |
Biology Articles | What happens if we take laboratory mice outside | Do you know what a mouse model is? The bodies of humans impacts the ability of mice to fight off intestinal worms. and mice have a lot in common. So scientists often use mice We took our laboratory-born mice outdoors to dig in dirt, (Mus musculus) as a model organism (or stand-in) to mimic search for food, and live like wild mice. But when we gave human diseases and discover how the body can stay healthy. them intestinal worms, the mice that lived outdoors couldnt Scientists usually keep mice in super clean environments clear the infection as well as indoor mice. In fact, the mice and test them under constant conditions. But most humans that lived outdoors the longest developed fatter and longer dont live in labs! So how well can a mouse model represent worms in their guts. Our outdoor mouse model shows the real life? We decided to test how a realistic environment effects of the environment on experimental results. | Genetic and environmental factors shape host susceptibility to infection, but how and how rapidly environmental variation might alter the susceptibility of mammalian genotypes remains unknown. Here, we investigate the impacts of seminatural environments upon the nematode susceptibility profiles of inbred C57BL/6 mice. We hypothesized that natural exposure to microbes might directly (e.g., via trophic interactions) or indirectly (e.g., via microbe-induced immune responses) alter the hatching, growth, and survival of nematodes in mice housed outdoors. We found that while C57BL/6 mice are resistant to high doses of nematode (Trichuris muris) eggs under clean laboratory conditions, exposure to outdoor environments significantly increased their susceptibility to infection, as evidenced by increased worm burdens and worm biomass. Indeed, mice kept outdoors harbored as many worms as signal transducer and activator of transcription 6 (STAT6) knockout mice, which are genetically deficient in the type 2 immune response essential for clearing nematodes. Using 16S ribosomal RNA sequencing of fecal samples, we discovered enhanced microbial diversity and specific bacterial taxa predictive of nematode burden in outdoor mice. We also observed decreased type 2 and increased type 1 immune responses in lamina propria and mesenteric lymph node (MLN) cells from infected mice residing outdoors. Importantly, in our experimental design, different groups of mice received nematode eggs either before or after moving outdoors. This contrasting timing of rewilding revealed that enhanced hatching of worms was not sufficient to explain the increased worm burdens; instead, microbial enhancement and type 1 immune facilitation of worm growth and survival, as hypothesized, were also necessary to explain our results. These findings demonstrate that environment can rapidly and significantly shape gut microbial communities and mucosal responses to nematode infections, leading to variation in parasite expulsion rates among genetically similar hosts. | https://doi.org/10.1371/journal.pbio.2004108 | Elementary school; Middle school |
Biology Articles | What happens to mother bees brains as they age | Youre probably familiar with honeybees and bumblebees. But did you know that there are over 20,000 species of bees, and most of them are solitary? In worker honeybees, certain brain areas grow larger as the insects get older and have more experiences. We wanted to know if this was also the case for solitary bees. We studied a particular type of solitary carpenter bee named Ceratina calcarata. We collected female bees of three different ages. Then we measured their brains and other body parts under a microscope. As expected, older female bees had smaller ovaries and more worn wings. But surprisingly, older bees had smaller brains than younger bees. We think that female C. calcarata bees invest their energy and resources into reproduction, rather than growing bigger brains. | Many insects show plasticity in the area of the brain called the mushroom bodies (MB) with foraging and social experience. MBs are paired neuropils associated with learning and memory. MB volume is typically greater in mature foragers relative to young and/or inexperienced individuals. Long-term studies show that extended experience may further increase MB volume, but long-term studies have only been performed on non-reproductive social insect workers. Here we use the subsocial beeCeratina calcaratato test the effect of extended foraging experience on MB volume among reproductive females.Ceratina calcaratafemales forage to provision their immature offspring in the spring, and then again to provision their adult daughters in the late summer. We measured the volume of the MB calyces and peduncle, antennal lobes (AL), optic lobes (OL), central complex (CX), and whole brains of three groups of bees: newly emerged females, reproductive females in spring (foundresses), and post-reproductive mothers feeding their adult daughters in late summer. Post-reproductive late summer mothers had smaller MB calyces and ALs than foundresses. Moreover, among late mothers (but not other bees), wing wear, which is a measure of foraging experience, negatively correlated with both MB and OL volume. This is contrary to previously studied non-reproductive social insect workers in which foraging experience correlates postiviely with MB volume, and suggests that post-reproductive bees may reduce neural investment near the end of their lives. | https://www.nature.com/articles/s41598-022-12281-7 | Middle school |
Biology Articles; Health-And-Medicine Articles | What happens to our immune cells as we get older | Our immune system fights off lots of infections which could We wanted to know how T cell numbers manage to stay so harm us. T cells are an important part of the immune system. stable. We used data from experiments performed on mice They recognize different infections and protect us from them. to test a variety of potential ways they might do this, using Our body makes lots of T cells when we are young, but slows mathematical models. Our experiments and models show that down production after puberty. Nevertheless, the numbers of T cells gradually increase their ability to survive the longer these cells in our body stays the same even when we are old. they stay in the blood system. | The processes regulating peripheral naive T-cell numbers and clonal diversity remain poorly understood. Conceptually, homeostatic mechanisms must fall into the broad categories of neutral (simple random birthdeath models), competition (regulation of cell numbers through quorum-sensing, perhaps via limiting shared resources), adaptation (involving cell-intrinsic changes in homeostatic fitness, defined as net growth rate over time), or selection (involving the loss or outgrowth of cell populations deriving from intercellular variation in fitness). There may also be stably maintained heterogeneity within the naive T-cell pool. To distinguish between these mechanisms, we confront very general models of these processes with an array of experimental data, both new and published. While reduced competition for homeostatic stimuli may impact cell survival or proliferation in neonates or under moderate to severe lymphopenia, we show that the only mechanism capable of explaining multiple, independent experimental studies of naive CD4+ and CD8+ T-cell homeostasis in mice from young adulthood into old age is one of adaptation, in which cells act independently and accrue a survival or proliferative advantage continuously with their post-thymic age. However, aged naive T cells may also be functionally impaired, and so the accumulation of older cells via conditioning through experience may contribute to reduced immune responsiveness in the elderly. | https://doi.org/10.1371/journal.pbio.2003949 | Lower high school; Upper high school |
Biology Articles | What helps plants get just the right amount of iron | Some things are crucial for life in small doses, but too much much of it they take in. How exactly do plants do this? of it can be harmful or even fatal. Take salt, for example. We looked at how the normal version and a mutant form of We cannot survive without it, but it can poison or even Thale cress regulate their iron uptake by comparing their kill us if we eat too much of it. Iron works similarly for gene products, root growth, and the amount and location many organisms, including plants. Plants cannot grow of chemical gene tags. We found that epigenetic factors or function without it, but too much iron can do a lot of are involved in controlling iron uptake. Read on to find out damage. Therefore, they need to carefully regulate how exactly what that means! | Iron is an essential micronutrient for nearly all organisms, but excessive iron can lead to the formation of cytotoxic reactive oxygen species. Therefore, iron acquisition and homeostasis must be tightly regulated. Plants have evolved complex mechanisms to optimize their use of iron, which is one of the most limiting nutrients in the soil. In particular, transcriptional regulation is vital for regulating iron in plants, and much work has revealed the role of transcription factors on this front. Our study adds novel insights to the transcriptional regulation of iron homeostasis in plants by showing that chromatin remodeling via histone 3 lysine 27 trimethylation (H3K27me3) modulates the expression of FIT-dependent genes under iron deficiency. We provide evidence that FIT-dependent iron acquisition genes, IRT1 and FRO2, as well as FIT itself are direct targets of PRC2-mediated H3K27me3. In the clf mutant, which lacks the predominant H3K27 tri-methyltransferase, induction of FIT, FRO2, IRT1, and other FIT-regulated genes in roots is significantly higher under iron deficient conditions than in wild type. Furthermore, we observe that clf mutants are more tolerant to iron deficiency than wild type, indicating that gene expression levels appear to be limiting the plants ability to access iron. We propose that H3K27me3 attenuates the induction of FIT-target genes under iron deficiency and hypothesize that this may serve as a mechanism to restrict the maximum level of induction of iron acquisition genes to prevent iron overload. | https://www.frontiersin.org/articles/10.3389/fpls.2019.00627/full | Lower high school; Upper high school |
Biology Articles; Health-And-Medicine Articles; Social-Science Articles | What if people use too much antibiotics | Antibiotics are miraculous drugs that help us fight off bacterial but has increased rapidly in middle and low-income countries. infections. But sometimes bacteria evolve resistance against (But per capita consumption there is still lower.) antibiotic treatment. Unnecessary use of antibiotics helps this Our analysis suggests that the main reason for this was antibiotic resistance spread faster. So it is important to study the growth in income, which made the medications more how much antibiotics people consume worldwide. accessible. But this also caused an increase in unnecessary We analyzed antibiotic-use data from countries between use. Economists predict that income will continue to grow and . We found that consumptions of these in the next years. So we need new strategies to reduce medications stayed constant in most high-income countries, unnecessary antibiotic consumption and resistance. | Tracking antibiotic consumption patterns over time and across countries could inform policies to optimize antibiotic prescribing and minimize antibiotic resistance, such as setting and enforcing per capita consumption targets or aiding investments in alternatives to antibiotics. In this study, we analyzed the trends and drivers of antibiotic consumption from 2000 to 2015 in 76 countries and projected total global antibiotic consumption through 2030. Between 2000 and 2015, antibiotic consumption, expressed in defined daily doses (DDD), increased 65% (21.134.8 billion DDDs), and the antibiotic consumption rate increased 39% (11.315.7 DDDs per 1,000 inhabitants per day). The increase was driven by low- and middle-income countries (LMICs), where rising consumption was correlated with gross domestic product per capita (GDPPC) growth (P = 0.004). In high-income countries (HICs), although overall consumption increased modestly, DDDs per 1,000 inhabitants per day fell 4%, and there was no correlation with GDPPC. Of particular concern was the rapid increase in the use of last-resort compounds, both in HICs and LMICs, such as glycylcyclines, oxazolidinones, carbapenems, and polymyxins. Projections of global antibiotic consumption in 2030, assuming no policy changes, were up to 200% higher than the 42 billion DDDs estimated in 2015. Although antibiotic consumption rates in most LMICs remain lower than in HICs despite higher bacterial disease burden, consumption in LMICs is rapidly converging to rates similar to HICs. Reducing global consumption is critical for reducing the threat of antibiotic resistance, but reduction efforts must balance access limitations in LMICs and take account of local and global resistance patterns. | https://www.pnas.org/content/115/15/E3463 | Lower high school; Upper high school |
Biology Articles | What kind of fungus are you | You may think of fungus as something gross and slimy, We wanted to find a way to classify large areas of trees but its actually an important part of the forest ecosystem! as either AM or ECM using information found in satellite Nearly all tree species depend on a symbiotic relationship imagery. To see if our technique worked, we compared the with one of two types of fungus called AM or ECM (comes results of our satellite measurements with observations we from arbuscular mycorrhizal and ectomycorrhizal). Which made by hiking through four different forest sites across fungus grows in the trees roots determines how nutrients the United States. are cycled and many other important things. | A central challenge in global ecology is the identification of key functional processes in ecosystems that scale, but do not require, data for individual species across landscapes. Given that nearly all tree species form symbiotic relationships with one of two types of mycorrhizal fungi arbuscular mycorrhizal (AM) and ectomycorrhizal (ECM) fungi and that AM- and ECM-dominated forests often have distinct nutrient economies, the detection and mapping of mycorrhizae over large areas could provide valuable insights about fundamental ecosystem processes such as nutrient cycling, species interactions, and overall forest productivity. We explored remotely sensed tree canopy spectral properties to detect underlying mycorrhizal association across a gradient of AM- and ECM-dominated forest plots. Statistical mining of reflectance and reflectance derivatives across moderate/high-resolution Landsat data revealed distinctly unique phenological signals that differentiated AM and ECM associations. This approach was trained and validated against measurements of tree species and mycorrhizal association across ~130 000 trees throughout the temperate United States. We were able to predict 77% of the variation in mycorrhizal association distribution within the forest plots (P < 0.001). The implications for this work move us toward mapping mycorrhizal association globally and advancing our understanding of biogeochemical cycling and other ecosystem processes. | http://onlinelibrary.wiley.com/doi/10.1111/gcb.13264/full | Lower high school; Upper high school |
Biology Articles; Food-And-Agriculture Articles | What mutations does wheat hide | Wheat is one of the most widely grown crops in the world mutations, i.e. the plants carry these mutated genes but and it provides us with % of calories and proteins. We they look the same as the original wild varieties. We wanted have farmed this plant since the dawn of agriculture many to discover the mutations hidden in wheat plants, so we thousands of years ago. Our cultivated wheat species have sequenced and cataloged more than million mutations in more than two copies of every gene, making it a polyploid mutant plants. We hope that this database of mutations plant. When there are many copies of each gene its harder in cultivated wheat will help researchers and breeders to for mutations (changes in sequence of DNA) to reveal study what different genes do and help them improve wheat themselves because the other copies hide the effects of the varieties. | Significance Pasta and bread wheat are polyploid species that carry multiple copies of each gene. Therefore, loss-of-function mutations in one gene copy are frequently masked by functional copies on other genomes. We sequenced the protein coding regions of 2,735 mutant lines and developed a public database including more than 10 million mutations. Researchers and breeders can search this database online, identify mutations in the different copies of their target gene, and request seeds to study gene function or improve wheat varieties. Mutations are being used to improve the nutritional value of wheat, increase the size of the wheat grains, and generate additional variability in flowering genes to improve wheat adaptation to new and changing environments. Comprehensive reverse genetic resources, which have been key to understanding gene function in diploid model organisms, are missing in many polyploid crops. Young polyploid species such as wheat, which was domesticated less than 10,000 y ago, have high levels of sequence identity among subgenomes that mask the effects of recessive alleles. Such redundancy reduces the probability of selection of favorable mutations during natural or human selection, but also allows wheat to tolerate high densities of induced mutations. Here we exploited this property to sequence and catalog more than 10 million mutations in the protein-coding regions of 2,735 mutant lines of tetraploid and hexaploid wheat. We detected, on average, 2,705 and 5,351 mutations per tetraploid and hexaploid line, respectively, which resulted in 3540 mutations per kb in each population. With these mutation densities, we identified an average of 2324 missense and truncation alleles per gene, with at least one truncation or deleterious missense mutation in more than 90% of the captured wheat genes per population. This public collection of mutant seed stocks and sequence data enables rapid identification of mutations in the different copies of the wheat genes, which can be combined to uncover previously hidden variation. Polyploidy is a central phenomenon in plant evolution, and many crop species have undergone recent genome duplication events. Therefore, the general strategy and methods developed herein can benefit other polyploid crops. | https://doi.org/10.1073/pnas.1619268114 | Lower high school; Upper high school |
Biology Articles; Paleoscience Articles; Social-Science Articles | Where did the first people in the Caribbean come from | The first modern humans (Homo sapiens) evolved in We learned that the first settlers of the Caribbean Africa around , years ago and then migrated came from Central or South America. They used (moved) to almost every corner of the globe! stone tools and probably gathered wild plants and Archaeological artifacts tell us that around , hunted animals. Another group of people moved years ago, people moved into the Caribbean for the into the Caribbean thousands of years later from first time. We wanted to use ancient DNA to find South America and brought clay pots and farming. out where these people had come from. To find this Ancient DNA can help us tell the story of people answer, we needed both archaeology and DNA. who lived thousands of years ago. And it can help us understand how they are connected to people living today! | Humans settled the Caribbean about 6,000years ago, and ceramic use and intensified agriculture mark a shift from the Archaic to the Ceramic Age at around 2,500years ago1,2,3. Here we report genome-wide data from 174ancient individuals from The Bahamas, Haiti and the Dominican Republic (collectively, Hispaniola), Puerto Rico, Cura?ao and Venezuela, which we co-analysed with 89previously published ancient individuals. Stone-tool-using Caribbean people, who first entered the Caribbean during the Archaic Age, derive from a deeply divergent population that is closest to Central and northern South Americanindividuals; contrary to previous work4, we find no support for ancestry contributed by a population related to North Americanindividuals. Archaic-related lineages were >98% replaced by a genetically homogeneous ceramic-using population related to speakers of languages in the Arawak family from northeast South America; these people moved through the Lesser Antilles and into the Greater Antilles at least 1,700years ago, introducing ancestry that is still present. Ancient Caribbean people avoided close kin unions despite limited mate pools that reflect small effective population sizes, which we estimate to be a minimum of 5001,500 and a maximum of 1,5308,150 individuals on the combined islands of Puerto Rico and Hispaniola in the dozens of generations before the individuals who we analysed lived. Census sizes are unlikely to be more than tenfold larger than effective population sizes, so previous pan-Caribbean estimates of hundreds of thousands of people are too large5,6. Confirming a small and interconnected Ceramic Age population7, we detect 19pairs of cross-island cousins, close relatives buriedaround 75km apart in Hispaniola and low genetic differentiation across islands. Genetic continuity across transitions in pottery styles reveals that cultural changes during the Ceramic Age were not driven by migration of genetically differentiated groups from the mainland, but instead reflected interactions within an interconnected Caribbean world1,8. | https://doi.org/10.1038/s41586-020-03053-2 | Lower high school; Middle school |
Biology Articles; Health-And-Medicine Articles | Which chickens are better at fighting off a virus and why | Have you ever heard of Newcastle disease? Its a dangerous viral infection among chickens and wild birds. It rarely infects people, but it is a threat to the global poultry industry. This is especially true in low and middle-income countries where its harder for farmers to protect their chickens. One strategy to combat Newcastle disease is to select for breeds of chicken which are less likely to get the disease. But which breeds resist Newcastle disease and what enables this resistance? To find out we compared the innate immune responses of different breeds of chicken. We looked at which ones were more likely to get infected. Our results revealed the higher expression of five common genes among these breeds. We also found that some versions of the breeds (known as sublines) express some unique genes. These genes might be the key to new breeding strategies that fight Newcastle disease. | Newcastle disease virus (NDV) is a threat to the global poultry industry, but particularly for smallholder farmers in low- and middle-income countries. Previous reports suggest that some breeds of chickens are less susceptible to NDV infection, however, the mechanisms contributing to this are unknown. We here examined the comparative transcriptional responses of innate immune genes to NDV infection in inbred sublines of the Fayoumi and Leghorn breeds known to differ in their relative susceptibility to infection as well as at the microchromosome bearing the major histocompatability complex (MHC) locus. The analysis identified a set of five core genes,Mx1,IRF1,IRF7,STAT1, andSOCS1, that are up-regulated regardless of subline. Several genes were differentially expressed in a breed- or subline-dependent manner. The breed-dependent response involvedTLR3,NOS2,LITAF, andIFIH1in the Fayoumi versusIL8,CAMP, andCCL4in the Leghorn. Further analysis identified subline-dependent differences in the pro-inflammatory response within the Fayoumi breed that are likely influenced by the MHC. These results have identified conserved, breed-dependent, and subline-dependent innate immune responses to NDV infection in chickens, and provide a strong framework for the future characterization of the specific roles of genes and pathways that influence the susceptibility of chickens to NDV infection. | https://www.nature.com/articles/s41598-019-43483-1 | Lower high school; Middle school |
Biology Articles | Why are North American velvet ants more colorful | What is your reaction when you see a brightly colored insect? Probably danger, stay away! And in fact, female Mutillidae, commonly known as velvet ants (but actually wasps, not ants), use their bright colors to deter predators. They also have a nasty sting. Many velvet ant species that live in the same location and environment look a lot like each other. When a predator learns that a particular species is harmful, it typically avoids all species that look similar. North American velvet ants can be placed into eight different color pattern groups. How about in Africa, where there are even more velvet ant species? Do they also mimic each other? We found four color pattern groups for African velvet ants. So its interesting that North America has far fewer velvet ant species than Africa, but more color pattern groups. Why? We think some possible reasons include fewer ecoregions and lower predator diversity in Africa. | Africa has the most tropical and subtropical land of any continent, yet has relatively low species richness in several taxa. This depauperate nature of the African tropical fauna and flora has led some to call Africa the "odd man out." One exception to this pattern is velvet ants (Hymenoptera: Mutillidae), wingless wasps that are known for M?llerian mimicry. While North American velvet ants form one of the world's largest mimicry complexes, mimicry in African species has not been investigated. Here we ask do African velvet ant M?llerian mimicry rings exist, and how do they compare to the North American complex. We then explore what factors might contribute to the differences in mimetic diversity between continents. To investigate this we compared the color patterns of 304 African velvet ant taxa using nonmetric multidimensional scaling (NMDS). We then investigated distributions of each distinct mimicry ring. Finally, we compared lizard diversity and ecoregion diversity on the two continents. We found that African female velvet ants form four M?llerian rings, which is half the number of North American rings. This lower mimetic diversity could be related to the relatively lower diversity of insectivorous lizard species or to the lower number of distinct ecoregions in Africa compared to North America. | https://doi.org/10.1371/journal.pone.0189482 | Lower high school; Middle school |
Biology Articles | Why do sharks sleep | We all know how it feels when we have not had enough could help us figure out how sleep evolved. Only one study sleep. You might feel tired or have trouble concentrating. has looked at sleep in sharks. We wanted to change this! You might even be grumpy or irritable. Even though sleep We looked at the sleeping behaviors of draughtsboard sharks is important to our daily lives, it is still a bit of a mystery. over hours. We found out that when sharks sleep, they Why do we sleep and how did sleep evolve? Scientists have usually lie flat and have a lower metabolic rate. This means started researching sleep in other animals to find out. that sleep can be important to help conserve energy. It also Sharks are hundreds of millions of years old. They are the helps us understand the evolution of sleep. oldest living group of vertebrates with jaws! We think sharks | Sharks represent the earliest group of jawed vertebrates and as such, they may provide original insight for understanding the evolution of sleep in more derived animals. Unfortunately, beyond a single behavioural investigation, very little is known about sleep in these ancient predators. As such, recordings of physiological indicators of sleep in sharks have never been reported. Reduced energy expenditure arising from sustained restfulness and lowered metabolic rate during sleep have given rise to the hypothesis that sleep plays an important role for energy conservation. To determine whether this idea applies also to sharks, we compared metabolic rates of draughtsboard sharks (Cephaloscyllium isabellum) during periods ostensibly thought to be sleep, along with restful and actively swimming sharks across a 24 h period. We also investigated behaviours that often characterize sleep in other animals, including eye closure and postural recumbency, to establish relationships between physiology and behaviour. Overall, lower metabolic rate and a flat body posture reflect sleep in draughtsboard sharks, whereas eye closure is a poorer indication of sleep. Our results support the idea for the conservation of energy as a function of sleep in these basal vertebrates. | https://royalsocietypublishing.org/doi/10.1098/rsbl.2021.0259 | Elementary school; Lower high school; Middle school |
Biology Articles | Why do some clownfish not breed | Clownfish are one of the most well-known tropical fish. But We decided to investigate the smaller clownfish. We looked even though we see them on our TV screens, what do you at the risks and rewards of moving to a different home to know about them in real life? They live in social groups in breed or of contesting to breed in their current home. We which individuals are ranked by size (size-based dominance found that its too risky for these clownfish to move to a new hierarchy). The two biggest dominant individuals breed home. Furthermore, they arent likely to contest by getting (have babies), but the smaller individuals do not. So why do bigger and potentially fight the dominants since they risk some clownfish forgo their own reproduction? being evicted from the group. So, they choose to stay put and wait in the hope that they will one day be able to breed. | Individuals that forgo their own reproduction in animal societies represent an evolutionary paradox because it is not immediately apparent how natural selection can preserve the genes that underlie non-breeding strategies. Cooperative breeding theory provides a solution to the paradox: non-breeders benefit by helping relatives and/or inheriting breeding positions; non-breeders do not disperse to breed elsewhere because of ecological constraints. However, the question of why non-breeders do not contest to breed within their group has rarely been addressed. Here, we use a wild population of clownfish (Amphiprion percula), where non-breeders wait peacefully for years to inherit breeding positions, to show non-breeders will disperse when ecological constraints (risk of mortality during dispersal) are experimentally weakened. In addition, we show non-breeders will contest when social constraints (risk of eviction during contest) are experimentally relaxed. Our results show it is the combination of ecological and social constraints that promote the evolution of non-breeding strategies. The findings highlight parallels between, and potential for fruitful exchange between, cooperative breeding theory and economic bargaining theory: individuals will forgo their own reproduction and wait peacefully to inherit breeding positions (engage in cooperative options) when there are harsh ecological constraints (poor outside options) and harsh social constraints (poor inside options). | https://www.nature.com/articles/s42003-020-01380-8 | Middle school |
Biology Articles | Why is it so hard to bring back extinct species | De-extinction is the science of bringing back extinct living species as a reference. By comparing DNA fragments species. But its very challenging. Scientists are testing out to the reference, you can put the pieces in the right order. lots of different ideas. One promising idea is to use genetic We used brown rats as a reference. Unfortunately, we engineering to piece together the DNA of an extinct species. found that some of the genes of the extinct species cant We analyzed old, fragmented DNA of the Christmas Island be recovered. This means that an animal brought back rat, which went extinct about years ago. For an extinct by genetic engineering wouldnt be an exact copy of the species, the only option is to use the genome of a similar, extinct species. | Three principal methods are under discussion as possible pathways to true de-extinction; i.e., back-breeding, cloning, and genetic engineering.1,2 Of these, while the latter approach is most likely to apply to the largest number of extinct species, its potential is constrained by the degree to which the extinct species genome can be reconstructed. We explore this question using the extinct Christmas Island rat (Rattus macleari) as a model, an endemic rat species that was driven extinct between 1898 and 1908.3, 4, 5 We first re-sequenced its genome to an average of >60? coverage, then mapped it to the reference genomes of different Rattus species. We then explored how evolutionary divergence from the extant reference genome affected the fraction of the Christmas Island rat genome that could be recovered. Our analyses show that even when the extremely high-quality Norway brown rat (R. norvegicus) is used as a reference, nearly 5% of the genome sequence is unrecoverable, with 1,661 genes recovered at lower than 90% completeness, and 26 completely absent. Furthermore, we find the distribution of regions affected is not random, but for example, if 90% completeness is used as the cutoff, genes related to immune response and olfaction are excessively affected. Ultimately, our approach demonstrates the importance of applying similar analyses to candidates for de-extinction through genome editing in order to provide critical baseline information about how representative the edited form would be of the extinct species. | https://www.sciencedirect.com/science/article/pii/S0960982222002494 | Middle school |
Chemistry Articles | Can materials made of the same elements have different properties | Did you know that everything around you contains special molecules called polymers? These molecules form long chains that make up plastic, protein, and even your DNA! The great thing about polymers is that we can design them to have the properties we need. But the polymers we design can sometimes have a negative impact on the environment. That is why we wanted to see if we can create different polymers from the same natural product, such as sugar. We wanted to determine how the placement of atoms in the polymers affected their properties. We found that by rearranging the atoms of a monomer, we could get two different polymers. One behaved like a stiff plastic, and the other behaved like stretchy rubber. The results of our research made us realize that the placement of atoms does change a polymers properties. It also proved that we can make strong and flexible polymers from more natural materials. | Stereochemistry in polymers can be used as an effective tool to control the mechanical and physical properties of the resulting materials. Typically, though, in synthetic polymers, differences among polymer stereoisomers leads to incremental property variation, i.e., no changes to the baseline plastic or elastic behavior. Here we show that stereochemical differences in sugar-based monomers yield a family of nonsegmented, alternating polyurethanes that can be either strong amorphous thermoplastic elastomers with properties that exceed most cross-linked rubbers or robust, semicrystalline thermoplastics with properties comparable to commercial plastics. The stereochemical differences in the monomers direct distinct intra- and interchain supramolecular hydrogen-bonding interactions in the bulk materials to define their behavior. The chemical similarity among these isohexide-based polymers enables both statistical copolymerization and blending, which each afford independent control over degradability and mechanical properties. The modular molecular design of the polymers provides an opportunity to create a family of materials with divergent properties that possess inherently built degradability and outstanding mechanical performance. | https://pubs.acs.org/doi/10.1021/jacs.1c10278?fig=tgr1&ref=pdf | Lower high school |
Chemistry Articles; Health-And-Medicine Articles; Pollution Articles | How can chemicals influence your hormones | Did you know that hormones not only influence your mood nearby. Hormones are particularly important in providing but also most of your bodys functions? They are messengers instructions for your development before you are born and involved in telling you when to feel hungry or when to get when you are a baby. tired, for example. It is very important to have the right We reviewed the scientific literature to find out how these levels of hormones in your body to stay healthy. But there chemicals get into our bodies and the environment. We are a lot of man-made chemicals that find their way into found that a lot of them get used in industrial processes or our environment. They can then disrupt those important are in pesticides. But some also turn up in food packaging biological messengers in the animals and humans living materials, cleaning products, or cosmetics. | Many classes of compounds are known or suspected to disrupt the endocrine system of vertebrate and invertebrate organisms. This review of the sources and fate of selected endocrine disrupting chemicals (EDCs) in the environment includes classes of compounds that are legacy contaminants, as well as contaminants of emerging concern. EDCs included for discussion are organochlorine compounds, halogenated aromatic hydrocarbons, brominated flame retardants, per- and polyfluoroalkyl substances, alkylphenols, phthalates, bisphenol A and analogues, pharmaceuticals, drugs of abuse and steroid hormones, personal care products, and organotins. An exhaustive survey of the fate of these contaminants in all environmental media (e.g., air, water, soil, biota, foods and beverages) is beyond the scope of this review, so the priority is to highlight the fate of EDCs in environmental media for which there is a clear link between exposure and endocrine effects in humans or in biota from other taxa. Where appropriate, linkages are also made between the fate of EDCs and regulatory limits such as environmental quality guidelines for water and sediments and total daily intake values for humans. | https://www.sciencedirect.com/science/article/pii/S0013935121019599 | Middle school |
Chemistry Articles; Energy-And-Climate Articles; Technology Articles | How can nanoparticles help coral reefs | Did you know that coral reefs are like incredible underwater cities built by corals? They protect coastlines and provide homes for many marine species, including tiny algae that live inside the coral. These algae have a special deal with the coral they share nutrients and give the coral its colorful beauty. But theres trouble! Rising ocean temperatures from climate change stress the corals. This makes coral lose their colorful algae partners in a process called coral bleaching. Its bad news for both the corals and the reefs.We made a drug for the algae to help fight the harmful effects of stress. The algae are small, so we made ceria nanoparticles that the algae can easily absorb. This protected the algae from harm, even when seawater temperatures were warm! | The breakdown of symbiotic mutualism between cnidarian hosts and dinoflagellate algae partners (i.e., bleaching) has been linked to an immune-like response pathway brought on by a nitro-oxidative burst, a symptom of thermal stress. Stress induced by reactive oxygen species (ROS)/reactive nitrogen species is a problem common to aerobic systems. In this study, we tested the antioxidant effects of engineered poly(acrylic acid)-coated cerium dioxide nanoparticles (CeO2, nanoceria) on free-living Symbiodiniaceae (Breviolum minutum), a dinoflagellate alga that forms symbiotic relationships with reef-building corals and anemones. Results show that poly(acrylic acid)-coated CeO2 with hydrodynamic diameters of ~4 nm are internalized by B. minutum in under 30 min and subsequently localized in the cytosol. Nanoceria exposure does not inhibit cell growth over time, with the treated cultures showing a similar growth trend over the 25-day exposure. Aerobic activity and thermal stress when held at 34C for 1 h (+6C above control) led to increased intracellular ROS concentration with time. A clear ROS scavenging effect of the nanoceria was observed, with a 5-fold decrease in intracellular ROS levels during thermal stress. The nitric oxide (NO) concentration decreased by ~17% with thermal stress, suggesting the rapid involvement of NO scavenging enzymes or proteins within 1 h of stress onset. The presence of nanoceria did not appear to influence NO concentration. Furthermore, aposymbiotic anemones (Exaiptasia diaphana, ex Aiptasia pallida) were successfully infected with nanoceria-loaded B. minutum, demonstrating that inoculation could serve as a delivery method. The ability of nanoceria to be taken up by Symbiodiniaceae and reduce ROS production could be leveraged as a potential mitigation strategy to reduce coral bleaching. | https://www.frontiersin.org/articles/10.3389/fmars.2022.960173/full | Lower high school |
Chemistry Articles; Pollution Articles | How can we recycle plastic more sustainably | Plastic is all around us: in our toothbrushes, pens, cars, and reuse it to make new plastic. We discovered an enzyme that even clothing! It is very useful. But plastic trash ends up digests plastic in the same way that humans can digest in the environment and is bad for animals and humans. It food. Using this enzyme to break down used plastic means can take hundreds of years to break down. Recycling this we will need much less energy to recycle plastic. Plus, we plastic can take a lot of energy and often still leaves waste. can even use the products of the process to make plastics We wanted to find a better way to break plastic down and that are just as good as new ones! | Earth is flooded with plastics and the need for sustainable recycling strategies for polymers has become increasingly urgent. Enzyme-based hydrolysis of post-consumer plastic is an emerging strategy for closed-loop recycling of polyethylene terephthalate (PET). The polyester hydrolase PHL7, isolated from a compost metagenome, completely hydrolyzes amorphous PET films, releasing 91?mg of terephthalic acid per hour and mg of enzyme. Vertical scanning interferometry shows degradation rates of the PET film of 6.8?m?h?1. Structural analysis indicates the importance of leucine at position 210 for the extraordinarily high PET-hydrolyzing activity of PHL7. Within 24?h, 0.6?mgenzyme?gPET?1 completely degrades post-consumer thermoform PET packaging in an aqueous buffer at 70?C without any energy-intensive pretreatments. Terephthalic acid recovered from the enzymatic hydrolysate is then used to synthesize virgin PET, demonstrating the potential of polyester hydrolases as catalysts in sustainable PET recycling processes with a low carbon footprint. | https://chemistry-europe.onlinelibrary.wiley.com/doi/10.1002/cssc.202101062 | Elementary school; Middle school |
Chemistry Articles; Energy-And-Climate Articles; Technology Articles | How can we store carbon dioxide from the atmosphere in minerals | Did you know that the sea level is rising and that weather patterns are changing worldwide? Because of human activities, there is extra carbon dioxide in the atmosphere. Thats why the Earth has gotten warmer. What can we do about it? We can take the carbon dioxide out of the atmosphere and store it. Current technologies transform it into a liquid and pump it back into the ground. Unfortunately, this way of doing things can be expensive and difficult to manage. Thats why we created a different method of collecting carbon dioxide from the atmosphere. Our process uses the natural ability of ocean water to absorb carbon dioxide from the atmosphere. Then it forms minerals that we can store or use. Our observations proved that our process successfully removes carbon dioxide from the atmosphere. Our analysis also showed that our method is more energy efficient and environmentally friendly than current technologies. | This perspective proposes a potential pathway to diminish atmospheric CO2 accumulations which is distinct from traditional carbon capture and geological sequestration strategies and from existing n... | https://pubs.acs.org/doi/10.1021/acssuschemeng.0c08561 | Lower high school; Middle school |
Chemistry Articles; Energy-And-Climate Articles; Technology Articles | How can we turn ocean water into renewable energy | Think about what life would be like without energy. No Hydrogen is a great renewable fuel that can be made refrigerators, no computers, no cars, and no cellphones! from water. Most of the water on Earth is saltwater, so we Today, most of the worlds energy comes from fossil fuels, created a device that can make hydrogen from it at a low which are nonrenewable resources (resources that take a cost. It combines the process of osmosis with the reaction long time for the Earth to make) that pollute our air and of water splitting. Our data show that this device is effective land. That is why we are trying to find cleaner, renewable and efficient, which means hydrogen could become more energy resources that can power our planet. available in the future. | Electrochemical water splitting stores energy as equivalents of hydrogen and oxygen and presents a potential route to the scalable storage of renewable energy. Widespread implementation of such energy storage, however, will be facilitated by abundant and accessible sources of water. We describe herein a means of utilizing impure water sources (e.g., saltwater) for electrochemical water splitting by leveraging forward osmosis. A concentration gradient induces the flow of water from an impure water source into a more concentrated designed electrolyte. This concentration gradient may subsequently be maintained by water splitting, where rates of water influx (i.e., forward osmosis) and effective outflux (i.e., water splitting) are balanced. This approach of coupling forward osmosis to water splitting allows for the use of impure and natural sources without pretreatment and with minimal losses in energy efficiency. | https://www.pnas.org/content/118/9/e2024855118 | Lower high school; Middle school |
Chemistry Articles; Paleoscience Articles | What can tusks tell us about the lives of mastodons | Did you know that tusks are enormous teeth? Many animals have them, but the biggest ones belong to elephants and their relatives, including mastodons. Mastodons are now extinct, but paleontologists can use fossil tusks to study the lives of these ancient giants. For our study, we analyzed the right tusk of a male mastodon found in 1998. We also analyzed two chemical elements preserved in the tusks: oxygen and strontium. Using different forms of these elements (called isotopes), we tracked the season when a particular layer of tusk was grown, as well as where he grew it. We learned that he traveled long distances to mate with females. He also had fights with other mastodons and even died during his final battle! | Under harsh Pleistocene climates, migration and other forms of seasonally patterned landscape use were likely critical for reproductive success of mastodons (Mammut americanum) and other megafauna. However, little is known about how their geographic ranges and mobility fluctuated seasonally or changed with sexual maturity. We used a spatially explicit movement model that coupled strontium and oxygen isotopes from two serially sampled intervals (5+ adolescent years and 3+ adult years) in a male mastodon tusk to test for changes in landscape use associated with maturation and reproductive phenology. The mastodons early adolescent home range was geographically restricted, with no evidence of seasonal preferences. Following inferred separation from the matriarchal herd (starting age 12 y), the adolescent males mobility increased as landscape use expanded away from his natal home range (likely central Indiana). As an adult, the mastodons monthly movements increased further. Landscape use also became seasonally structured, with some areas, including northeast Indiana, used only during the inferred mastodon mating season (spring/summer). The mastodon died in this area (>150 km from his core, nonsummer range) after sustaining a craniofacial injury consistent with a fatal blow from a competing males tusk during a battle over access to mates. Northeast Indiana was likely a preferred mating area for this individual and may have been regionally significant for late Pleistocene mastodons. Similarities between mammutids and elephantids in herd structure, tusk dimorphism, tusk function, and the geographic component of male maturation indicate that these traits were likely inherited from a common ancestor. | https://www.pnas.org/doi/full/10.1073/pnas.2118329119 | Middle school |
Chemistry Articles | What can we learn from carbon on Mars | Mars is dry and cold. It doesnt have much of an atmosphere. bed. We looked at the carbon to see how much there was But what was it like in the past? Did Mars ever have an and where it came from. This could give us clues about what environment that could support life? Luckily, we have rovers the environment used to be like. It could also help us figure on the surface of Mars that can help us answer these out if there used to be living things in the area. We found questions. that there was more carbon on Mars than we expected. Most of the carbon probably came from meteorites and rocks. We Carbon is a key component of living things. So, we used the cant rule out that it came from living things, but we need a Curiosity Rover on Mars to sample the surface for carbon. lot more information to help us figure it out. We sampled in an area that might have been a dried-up lake | The Sample Analysis at Mars instrument stepped combustion experiment on a Yellowknife Bay mudstone at Gale crater, Mars revealed the presence of organic carbon of Martian and meteoritic origins. The combustion experiment was designed to access refractory organic carbon in Mars surface sediments by heating samples in the presence of oxygen to combust carbon to CO2. Four steps were performed, two at low temperatures (less than ?550?C) and two at high temperatures (up to ?870?C). More than 950 g C/g was released at low temperatures (with an isotopic composition of 13C = +1.5 3.8) representing a minimum of 431 g C/g indigenous organic and inorganic Martian carbon components. Above 550?C, 273 30 g C/g was evolved as CO2 and CO (with estimated 13C = ?32.9 to ?10.1 for organic carbon). The source of high temperature organic carbon cannot be definitively confirmed by isotopic composition, which is consistent with macromolecular organic carbon of igneous origin, meteoritic infall, or diagenetically altered biomass, or a combination of these. If from allochthonous deposition, organic carbon could have supported both prebiotic organic chemistry and heterotrophic metabolism at Gale crater, Mars, at ?3.5 Ga. | https://www.pnas.org/doi/suppl/10.1073/pnas.2201139119 | Lower high school; Middle school; Upper high school |
Energy-And-Climate Articles; Social-Science Articles | A burning question How much will climate change cost | Earths climate is changing and summers in many places are getting gas concentrations in the atmosphere continue to rise, then many warmer and longer. If you live in a relatively cold region, such as Canadian provinces could experience extreme fire years more Canada, warmer summers might not sound too bad. Yet a closer often than ever. Consequently, Canadians may be spending a look into the long-term effects would surely give you the chills. whopping $. billion annually (a % increase) by the end of the century to fight those fires. This does not even include human In this study, we focused on one of these effects: increases in health evacuation costs or insurance payouts. the area burned by wildfires and the cost of fighting them. We examined historical data and used models to predict future costs. Our calculations revealed some eye-opening news. If greenhouse | Climate-influenced changes in fire regimes in northern temperate and boreal regions will have both ecological and economic ramifications. We examine possible future wildfire area burned and suppression costs using a recently compiled historical (i.e., 19802009) fire management cost database for Canada and several Intergovernmental Panel on Climate Change (IPCC) climate projections. Area burned was modelled as a function of a climate moisture index (CMI), and fire suppression costs then estimated as a function of area burned. Future estimates of area burned were generated from projections of the CMI under two emissions pathways for four General Circulation Models (GCMs); these estimates were constrained to ecologically reasonable values by incorporating a minimum fire return interval of 20 years. Total average annual national fire management costs are projected to increase to just under $1 billion (a 60% real increase from the 19802009 period) under the low greenhouse gas emissions pathway and $1.4 billion (119% real increase from the base period) under the high emissions pathway by the end of the century. For many provinces, annual costs that are currently considered extreme (i.e., occur once every ten years) are projected to become commonplace (i.e., occur once every two years or more often) as the century progresses. It is highly likely that evaluations of current wildland fire management paradigms will be necessary to avoid drastic and untenable cost increases as the century progresses. | http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0157425 | Lower high school |
Energy-And-Climate Articles | Are we powering our way into a climate crisis | Do you own lots of things that run on electricity? Now think greenhouse gases into the atmosphere - heating it, and our about all the things for which the electricity use is hidden planet, up. We wanted to know how many current or future Clothes, food, houses (and more) dont need to be plugged power plants we could run whilst complying with the Paris in, but they still need a lot of electricity to be made. Our climate agreement, which set a worldwide goal for limiting modern world depends on electricity, so its no surprise greenhouse gases. The answer is tough: at our current that we use a lot of energy to create it. Unfortunately, most rate, were already missing our goal! And that doesnt even electricity is still made from fossil fuels, which release tons of include all the power plants planned for the future. | Over the coming decade, the power sector is expected to invest ~7.2 trillion USD in power plants and grids globally, much of it into CO2-emitting coal and gas plants. These assets typically have long lifetimes and commit large amounts of (future) CO2 emissions. Here, we analyze the historic development of emission commitments from power plants and compare the emissions committed by current and planned plants with remaining carbon budgets. Based on this comparison we derive the likely amount of stranded assets that would be required to meet the 1.5?C2?C global warming goal. We find that even though the growth of emission commitments has slowed down in recent years, currently operating generators still commit us to emissions (~300?GtCO2) above the levels compatible with the average 1.5?C2?C scenario (~240?GtCO2). Furthermore, the current pipeline of power plants would add almost the same amount of additional commitments (~270?GtCO2). Even if the entire pipeline was cancelled, therefore, ~20% of global capacity would need to be stranded to meet the climate goals set out in the Paris Agreement. Our results can help companies and investors re-assess their investments in fossil-fuel power plants, and policymakers strengthen their policies to avoid further carbon lock-in. | http://iopscience.iop.org/article/10.1088/1748-9326/aabc5f/meta | Lower high school; Middle school |
Energy-And-Climate Articles; Social-Science Articles | Can electricity reach the billion people who live without it | Living in the U.S., it is hard to imagine a life without reliable and unlimited access to affordable electricity. Globally, however, 1.3 billion people four times the population of the U.S. lack this basic resource. Simply scaling up the energy supply with conventional coal, diesel and gas plants the mainstay of the electricity system worldwide today would be really expensive. In addition, building enough large fossil fuel power plants or hydroelectric megadams to distribute electricity to every single one of these people would be very unhealthy for people and the environment. However, this does not mean they are doomed to houses lit by candles and smoky paraffin lamps. (Just imagine writing your homework under the light of a kerosene lamp as a poor Kenyan student might be forced to do. Our research produced a vision of the future where every person on the planet has access to at least basic electricity. What we see in the field is a revolution where small family-scale energy systems that provide lighting, cell-phone charging, televisions, and refrigerators all powered by solar cells is changing the way that energy is accessed. Electrical power can now be produced for people off the grid by rooftop or backyard solar, or by a small power station in their neighborhood, or by a large power station somewhere far away and delivered via the grid. The change is not only in the source of energy but in the business model, too. A rural family in Kenya can now pay their electrical bill using a mobile phone and an online payment system. With electric lights to study, students in rural Kenya (and elsewhere) have a better opportunity to graduate from school. Never in history have we had so many choices about where to get our electricity and how to pay for it. Solar panel prices have been rapidly declining over the past 20 years. Modern, efficient electrical appliances only require a fraction of the energy old ones did. (Ever seen those 100 W incandescent light bulbs? Yeah, nobody uses them anymore. They switched to 10 W LED light bulbs a long time ago. | In Sub-Saharan Africa, 600 million people live without electricity. Despite ambitions of governments and donors to invest in rural electrification, decisions about how to extend electricity access are being made in the absence of rigorous evidence. In this paper, we present high-resolution spatial data on electrification rates in rural Kenya in order to quantify and visualize energy poverty in a novel way. Using our dataset of 20,000 geo-tagged structures in Western Kenya, we provide descriptive evidence that electrification rates remain very low despite significant investments in nearby grid infrastructure. This pattern holds across time and for both poor and relatively well-off households and businesses. We argue that if governments wish to leverage existing infrastructure and economies of scale, subsidies and new approaches to financing connections are necessary. | https://rael.berkeley.edu/publication/decentralized-energy-systems-for-clean-electricity-access/ | Lower high school; Middle school |
Energy-And-Climate Articles | Cold ocean hot summer | Climate change is causing the Earth to get hotter; 2015 is the hottest year ever recorded and is on course to be surpassed by 2016. Extreme heat waves are getting more common, causing untimely deaths for vulnerable populations like elderly people, as well as increased energy requirements for air conditioning and problems for natural ecosystems.We noticed that in the months just before Central Europe experienced an especially harsh heat wave in the summer of 2015, the surface temperatures in the Northeast Atlantic Ocean were exceptionally cold. Yes, cold. Why would the ocean be extra-cold before the air over land was extra-warm? Could these unusually cool ocean surface temperatures in the North Atlantic ocean be a precursor to heat waves in Europe? If so, monitoring ocean temperatures could help us predict and prepare for heat waves in the future. | The North Atlantic and Europe experienced two extreme climate events in 2015: exceptionally cold ocean surface temperatures and a summer heat wave ranked in the top ten over the past 65 years. Here, we show that the cold ocean temperatures were the most extreme in the modern record over much of the mid-high latitude North-East Atlantic. Further, by considering surface heat loss, ocean heat content and wind driven upwelling we explain for the first time the genesis of this cold ocean anomaly. We find that it is primarily due to extreme ocean heat loss driven by atmospheric circulation changes in the preceding two winters combined with the re-emergence of cold ocean water masses. Furthermore, we reveal that a similar cold Atlantic anomaly was also present prior to the most extreme European heat waves since the 1980s indicating that it is a common factor in the development of these events. For the specific case of 2015, we show that the ocean anomaly is linked to a stationary position of the Jet Stream that favours the development of high surface temperatures over Central Europe during the heat wave. Our study calls for an urgent assessment of the impact of ocean drivers on major European summer temperature extremes in order to provide better advance warning measures of these high societal impact events. | http://iopscience.iop.org/article/10.1088/1748-9326/11/7/074004 | Lower high school |
Energy-And-Climate Articles | Did atmospheric waves get wavier | Have you ever seen those wavy lines on a weather map? than Alaska! We wanted to know how wavy those waves Those lines are called isohypses (similar to isobars) and are, and if the waviness is changing over time. To find out, those large waves have a big impact on our weather. Bigger we developed a way to count the waviest waves and then waves mean more strange temperature extremes, like long compared data for the last thirty years. Climate change might heat waves, or long periods of freezing weather. If the waves actually make the waves wavier. And that might lead to more are really large, you can have a day where Ohio is colder extreme weatherheat waves and cold snapsin the future. | Strong waves in the mid-latitude circulation have been linked to extreme surface weather and thus changes in waviness could have serious consequences for society. Several theories have been proposed which could alter waviness, including tropical sea surface temperature anomalies or rapid climate change in the Arctic. However, so far it remains unclear whether any changes in waviness have actually occurred. Here we propose a novel meandering index which captures the maximum waviness in geopotential height contours at any given day, using all information of the full spatial position of each contour. Data are analysed on different time scale (from daily to 11 day running means) and both on hemispheric and regional scales. Using quantile regressions, we analyse how seasonal distributions of this index have changed over 19792015. The most robust changes are detected for autumn which has seen a pronounced increase in strongly meandering patterns at the hemispheric level as well as over the Eurasian sector. In summer for both the hemisphere and the Eurasian sector, significant downward trends in meandering are detected on daily timescales which is consistent with the recently reported decrease in summer storm track activity. The American sector shows the strongest increase in meandering in the warm season: in particular for 11 day running mean data, indicating enhanced amplitudes of quasi-stationary waves. Our findings have implications for both the occurrence of recent cold spells and persistent heat waves in the mid-latitudes | http://iopscience.iop.org/article/10.1088/1748-9326/11/9/094028 | Upper high school |
Energy-And-Climate Articles; Social-Science Articles | Do hot neighborhoods affect everyone equally | Have you ever noticed how it can be really hot on the It turns out that people of color have higher exposure to sidewalk, but comfortable and cool under a tree? In a city, the urban heat island effect than white people in all but six of where there are lots of buildings and roads, it can get hotter these cities! Poor people also usually have higher exposure. than the countryside. There is a name for this: the urban climate change is going to make hot days even hotter. We heat island effect. We wanted to know whether the urban hope that city leaders use our data to help neighborhoods heat island effect affects everyone in cities equally. We prepare for climate change. looked at data about big cities in the United States. | Urban heat stress poses a major risk to public health. Case studies of individual cities suggest that heat exposure, like other environmental stressors, may be unequally distributed across income groups. There is little evidence, however, as to whether such disparities are pervasive. We combine surface urban heat island (SUHI) data, a proxy for isolating the urban contribution to additional heat exposure in built environments, with census tract-level demographic data to answer these questions for summer days, when heat exposure is likely to be at a maximum. We find that the average person of color lives in a census tract with higher SUHI intensity than non-Hispanic whites in all but 6 of the 175 largest urbanized areas in the continental United States. A similar pattern emerges for people living in households below the poverty line relative to those at more than two times the poverty line. | https://doi.org/10.1038/s41467-021-23972-6 | Lower high school; Middle school |
Energy-And-Climate Articles; Food-And-Agriculture Articles | How are apple farmers adapting to climate change | Farmers, more than anyone else in the world, depend on both types of activities could provide the best adaptation predictable and stable weather patterns to do their job. to climate change. To be sure, though, further on-farm Climate change, therefore, poses a significant threat to studies are needed to confirm this recommendation. food production worldwide. Agriculturalists have been doing their best to adapt to these changes, but we dont really know exactly what the farmers have been doing (or why). | Agriculture is one of the most vulnerable sectors to climate change. Farmers have been exposed to multiple stressors including climate change, and they have managed to adapt to those risks. The adaptation actions undertaken by farmers and their decision making are, however, only poorly understood. By studying adaptation practices undertaken by apple farmers in three regions: Nagano and Kazuno in Japan and Elgin in South Africa, we categorize the adaptation actions into two types: farmer initiated bottom-up adaptation and institution led top-down adaptation. We found that the driver which differentiates the type of adaptation likely adopted was strongly related to the farmers characteristics, particularly their dependence on the institutions, e.g. the farmers cooperative, in selling their products. The farmers who rely on the farmers cooperative for their sales are likely to adopt the institution-led adaptation, whereas the farmers who have established their own sales channels tend to start innovative actions by bottom-up. We further argue that even though the two types have contrasting features, the combinations of the both types of adaptations could lead to more successful adaptation particularly in agriculture. This study also emphasizes that more farm-level studies for various crops and regions are warranted to provide substantial feedbacks to adaptation policy. | https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0120563 | Lower high school; Middle school |
Energy-And-Climate Articles; Food-And-Agriculture Articles | How can CO2 help agriculture in the face of climate change | Humans are increasing the amount of carbon dioxide (CO2) in the air through CO2 emissions. This is changing the climate, making life harder for many plants in areas that suffer from heat and drought. However, plants need CO2 to grow, and more CO2 can make them grow better. So will plants overall benefit from increased CO2 level or suffer from it?We wanted to test if the positive effect would offset the negative ones. To do so, we used scientific models to calculate future crop production and water use of four important crops all over the world under different scenarios of CO2 emissions and climate change.Our calculations show that although there will be large reductions in crop yield due to climate change over the next century, some crops will still be able to grow well. This is also because crops can grow with less water when CO2 levels are raised. | Rising atmospheric CO2concentrations ([CO2]) are expected to enhance photosynthesis and reduce crop water use1. However, there is high uncertainty about the global implications of these effects for future crop production and agricultural water requirements under climate change. Here we combine results from networks of field experiments1,2and global crop models3to present a spatially explicit global perspective on crop water productivity (CWP, the ratio of crop yield to evapotranspiration) for wheat, maize, rice and soybean under elevated [CO2] and associated climate change projected for a high-end greenhouse gas emissions scenario. We find CO2effects increase global CWP by 10[0;47]%27[7;37]% (median[interquartile range] across the model ensemble) by the 2080s depending on crop types, with particularly large increases in arid regions (by up to 48[25;56]% for rainfed wheat). If realized in the fields, the effects of elevated [CO2] could considerably mitigate global yield losses whilst reducing agricultural consumptive water use (417%). We identify regional disparities driven by differences in growing conditions across agro-ecosystems that could have implications for increasing food production without compromising water security. Finally, our results demonstrate the need to expand field experiments and encourage greater consistency in modelling the effects of rising [CO2] across crop and hydrological modelling communities. | https://www.nature.com/articles/nclimate2995?proof=true&draft=journal | Upper high school |
Energy-And-Climate Articles; Water-Resources Articles | How can the eruption of a volcano affect the ocean everywhere on Earth | Did you know that a volcanic eruption can affect the entire world? When the Hunga Tonga-Hunga Haapai volcano erupted on January 15, 2022, it affected the ocean everywhere. Thats because it created an atmospheric wave that disturbed the ocean. It also generated a tsunami. We analyzed weather station and tidal gauge data to learn more about the effects of the Hunga Tonga-Hunga Haapai volcanic eruption on Mexico. We learned that the atmospheric wave moved across the world many times. We also learned that the tsunami reached heights of up to 2 meters (6.5 feet) along the Pacific coast of Mexico. Our analysis of the tsunami warning system in Mexico showed that most people were not informed to stay away from the ocean. Based on our analysis, we recommend making changes to tsunami warning systems. | The massive explosion by the January 15, 2022 Hunga Tonga-Hunga Haapai volcano in Tonga triggered a trans-oceanic tsunami generated by coupled ocean and atmospheric shock waves during the explosion. The tsunami reached first the coast of Tonga, and later many coasts around the world. The shock wave went around the globe, causing sea perturbations as far as the Caribbean and the Mediterranean seas. We present the effects of the January 15, 2022 Tonga tsunami on the Mexican Pacific Coast, Gulf of Mexico, and Mexican Caribbean coast, and discuss the underrated hazard caused by great volcanic explosions, and the role of early tsunami warning systems, in particular in Mexico. The shock wave took about 7.5h to reach the coast of Mexico, located about 9000km away from the volcano, and the signal lasted several hours, about 133h (5.13days). The shock wave was the only cause for sea alterations on the Gulf of Mexico and Caribbean Sea, while at the Mexican Pacific coast both shock wave and the triggered tsunami by the volcano eruption and collapse affected this coast. The first tsunami waves recorded on the Mexican Pacific coast arrived around 12:35 on January 15, at the L?zaro C?rdenas, Michoac?n tide gauge station. The maximum tsunami height exceeded 2m at the Ensenada, Baja California, and Manzanillo, Colima, tide gauge stations. Most tsunami warning advisories, with two exceptions, reached communities via social media (Twitter and Facebook), but did not clearly state that people must stay away from the shore. We suggest that, although no casualties were reported in Mexico, tsunami warning advisories of far-field tsunamis and those triggered non-seismic sources, such as landslides and volcanic eruptions, should be included and improved to reach coastal communities timely, explaining the associated hazards on the coast. | https://link.springer.com/article/10.1007/s00024-022-03017-9 | Elementary school; Lower high school; Middle school |
Energy-And-Climate Articles; Food-And-Agriculture Articles; Pollution Articles | How can we make biofuels more climate friendly | Wouldnt it be great to find a fuel that powers our cars and planes without polluting the environment or warming up our planet? Fuels made from plants, like corn or sugarcane, called biofuels, appeared to be more climate-friendly than burning fossil fuels. Unfortunately, it turns out that many biofuels are no better, if not worse, than their fossil fuel counterparts in their impact on our climate. This is because they use up more fossil fuels in their production than they were meant to save! We wanted to see if we could change that and find a more climate-friendly way to produce biofuels. And we did! We found two promising candidates that we tested in field experiments in Hawaii. We showed that a conservation-oriented production method (no tillage, less water, less fertilizer) and good crop selection are crucial for producing better biofuels. | Replacing fossil fuel with biofuel is environmentally viable from a climate change perspective only if the net greenhouse gas (GHG) footprint of the system is reduced. The effects of replacing annual arable crops with perennial bioenergy feedstocks on net GHG production and soil carbon (C) stock are critical to the system-level balance. Here, we compared GHG flux, crop yield, root biomass, and soil C stock under two potential tropical, perennial grass biofuel feedstocks: conventional sugarcane and ratoon-harvested, zero-tillage napiergrass. Evaluations were conducted at two irrigation levels, 100% of plantation application and at a 50% deficit. Peaks and troughs of GHG emission followed agronomic events such as ratoon harvest of napiergrass and fertilization. Yet, net GHG flux was dominated by carbon dioxide (CO2), as methane was oxidized and nitrous oxide (N2O) emission was very low even following fertilization. High N2O fluxes that frequently negate other greenhouse gas benefits that come from replacing fossil fuels with agronomic forms of bioenergy were mitigated by efficient water and fertilizer management, including direct injection of fertilizer into buried irrigation lines. From soil intensively cultivated for a century in sugarcane, soil C stock and root biomass increased rapidly following cultivation in grasses selected for robust root systems and drought tolerance. The net soil C increase over the two-year crop cycle was three-fold greater than the annualized soil surface CO2 flux. Deficit irrigation reduced yield, but increased soil C accumulation as proportionately more photosynthetic resources were allocated belowground. In the first two years of cultivation napiergrass did not increase net greenhouse warming potential (GWP) compared to sugarcane, and has the advantage of multiple ratoon harvests per year and less negative effects of deficit irrigation to yield. | http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0168510 | Lower high school; Upper high school |
Energy-And-Climate Articles; Social-Science Articles; Water-Resources Articles | How can we prepare for droughts | Droughts are common in many parts of the world. Yet We analyzed drought projections for Texas a large state in climate change has made them more severe and difficult to the USA with both wet and dry regions. They show that the predict. This makes it harder for water suppliers to plan for conditions there will be even drier and hotter in the future. the future. Currently, they use data from past droughts to Water planning needs to adapt to these changes and take make these decisions. But we think its important to consider future climate change into account. Climate models would future changes as well. be very helpful for that. | Long-range water planning is complicated by factors that are rapidly changing in the 21st century, including climate, population, and water use. Here, we analyze climate factors and drought projections for Texas as an example of a diverse society straddling an aridity gradient to examine how the projections can best serve water stakeholder needs. We find that climate models are robust in projecting drying of summer-season soil moisture and decreasing reservoir supplies for both the eastern and western portions of Texas during the 21st century. Further, projections indicate drier conditions during the latter half of the 21st century than even the most arid centuries of the last 1,000 years that included megadroughts. To illustrate how accounting for drought nonstationarity may increase water resiliency, we consider generalized case studies involving four key stakeholder groups: agricultural producers, large surface water suppliers, small groundwater management districts, and regional water planning districts. We also examine an example of customized climate information being used as input to long-range water planning. We find that while stakeholders value the quantitative capability of climate model outputs, more specific climate-related information better supports resilience planning across multiple stakeholder groups. New suites of tools could provide necessary capacity for both short- and long-term, stakeholder-specific adaptive planning. | http://dx.doi.org/10.1029/2020EF001552 | Lower high school; Middle school |
Energy-And-Climate Articles; Water-Resources Articles | How can we protect the seabed from storms | Have you seen any unusual weather recently? One of the a difference? Some areas of the sea are protected from changes we may see because of climate change is more destructive fishing methods. These areas are called Marine severe storms in the UK. When storms hit the coastline, they Protected Areas. We wanted to find out if the organisms in create strong waves. This really shakes up the organisms these areas are better at facing and recovering from severe living on the seabed. But do methods of fishing also make storms than fished areas. | Marine protected areas (MPAs) are employed as tools to manage human impacts, especially fishing pressure. By excluding the most destructive activities MPAs can rewild degraded areas of seabed habitat. The potential for MPAs to increase ecosystem resilience from storms is, however, not understood, nor how such events impact seabed habitats. Extreme storm disturbance impact was studied in Lyme Bay MPA, Southwest United Kingdom, where the 2008 exclusion of bottom-towed fishing from the whole site allowed recovery of degraded temperate reef assemblages to a more complex community. Severe storm impacts in 20132014 resulted in major damage to the seabed so that assemblages in the MPA were more similar to sites where fishing continued than at any point since the designation of the MPA; the communities were not dominated by species resistant to physical disturbance. Nevertheless, annual surveys since 2014 have demonstrated that the initial recovery of MPA assemblages was much quicker than that seen following the cessation of chronic towed fishing impact in 2008. Likewise, General Additive Mixed Effect Models (GAMMs) showed that inside the MPA increases in diversity metrics post-Storm were greater and more consistent over time than post-Bottom-Towed Fishing. As extreme events are likely to become more common with climate change, wave exposure observations indicated that 29% of coastal reef MPAs around the United Kingdom may be exposed to comparable wave climate extremes, and may be similarly impacted. This paper therefore provides an insight into the likely extent and magnitude of ecological responses of seabed ecosystems to future extreme disturbance events. | https://www.frontiersin.org/articles/10.3389/fmars.2021.671427/full | Lower high school; Middle school |
Energy-And-Climate Articles; Food-And-Agriculture Articles | How can we reduce our environmental footprint one food at a time | Have you ever wondered what you can do to help the environment and slow climate change? What about eating certain foods because they are better for the environment? Producing the food you eat uses a lot of water and releases gases that warm the planet. If you ate foods that had a smaller impact on the environment, you could help fight climate change.But its hard for most people to change their entire diet! So we wondered if replacing just one food could reduce a persons impact on the environment. We collected diet data from a national survey in the USA. We figured out which foods produced the most carbon emissions. Then we created new potential diets where we substituted foods that had a smaller impact. We found that replacing beef products reduced carbon emissions and water use the most. That means not eating beef can lower the impact of your diet on the environment. | Background: Human food systems substantially affect the environment, but the impacts vary widely by food. Guidance to individuals to reduce their dietary impacts would benefit from easy advice, but little is known about the specific population impacts of simple changes on self-selected diets. Objectives: The objective was to estimate the potential impact of a single dietary substitution on the carbon and water scarcity footprints of self-selected diets in the United States. Methods: This cross-sectional modeling study used 24-h dietary recall data from the 2005-2010 waves of the NHANES. Greenhouse gas emissions (GHGE) in the production of foods as well as irrigated water use, characterized by its relative scarcity at production locations, were matched to all foods in the recalls using previously developed databases. Impacts were summed to create carbon and water scarcity footprints for diets (n = 16,800) of adults aged >18 y. Diet quality was assessed using the Healthy Eating Index (HEI). Foods with the highest impact on GHGE and selected additional foods were substituted for calorically equivalent, less impactful items. Footprints were calculated before and after these hypothetical substitutions. Results: The highest impact foods were all beef items, and 19.8% of individuals consumed them (n = 3320). After substitution of these items with poultry or pork, the mean carbon and water scarcity footprints among those with substitutions significantly decreased (P < 0.001) by 48.4 0.6% and 29.9 0.4%, respectively. Across the entire sample, these represented mean reductions of 9.6 0.3% and 5.9 0.2%, respectively. The mean HEI after substitutions was 3.6 0.1% higher than before (P < 0.001). None of the selected additional foods had population impacts as large as the beef substitutions. Conclusions: Simple substitutions can be made in individuals' diets to substantially reduce their carbon and water scarcity footprints without sacrificing dietary quality. Such substitutions may be easier to promote than complex dietary patterns. | https://pubmed.ncbi.nlm.nih.gov/35024805/ | Lower high school; Middle school |
Energy-And-Climate Articles; Food-And-Agriculture Articles; Social-Science Articles | How do our food choices affect the environment | Which diets are the most healthy and environmentally sustainable? Many scientists have tried to answer this question by researching the impacts of peoples food choices on health and the environment. We compiled all this previous research to summarize how changes to what we eat would affect water use, land use, greenhouse gas emissions, and human health. Overall, we found that if people shifted their diets to eat less animal-sourced food and more fruits and vegetables, it would generally reduce environmental impacts. Furthermore, there would also likely be benefits to health. | Food production is a major driver of greenhouse gas (GHG) emissions, water and land use, and dietary risk factors are contributors to non-communicable diseases. Shifts in dietary patterns can therefore potentially provide benefits for both the environment and health. However, there is uncertainty about the magnitude of these impacts, and the dietary changes necessary to achieve them. We systematically review the evidence on changes in GHG emissions, land use, and water use, from shifting current dietary intakes to environmentally sustainable dietary patterns. We find 14 common sustainable dietary patterns across reviewed studies, with reductions as high as 7080% of GHG emissions and land use, and 50% of water use (with medians of about 2030% for these indicators across all studies) possible by adopting sustainable dietary patterns. Reductions in environmental footprints were generally proportional to the magnitude of animal-based food restriction. Dietary shifts also yielded modest benefits in all-cause mortality risk. Our review reveals that environmental and health benefits are possible by shifting current Western diets to a variety of more sustainable dietary patterns. | http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0165797 | Lower high school; Upper high school |
Energy-And-Climate Articles | How do some algae make the Earth warmer | If you have ever visited a lake, a pond, or even the ocean, then you know about algae not only the big ones that wash up on the beach, but also the much smaller microalgae. Responsible for the green you see on the water, these tiny organisms are not only the foundation of the aquatic food web, but they also photosynthesize. That means they take carbon dioxide out of the atmosphere like plants. And we all know how important that is because of global warming! Interestingly, some algae also produce nitrous oxide another greenhouse gas. We wanted to find out which type of algae produces it and how they create it. We tested different types of algae in both light and dark environments, which made us realize that only green algae make nitrous oxide from nitric oxide, and they have different ways of doing it based on the amount of light available. We also linked the nitric oxide production to fertilizers, implying that there may be a way to reduce the amount of nitrous oxide produced by algae in the future. | Significance Nitrous oxide (N2O), the third most important greenhouse gas in the atmosphere, is produced in great quantities by microalgae, but molecular mechanisms remain elusive. Here we show that the green microalga Chlamydomonas reinhardtii produces N2O in the light by a reduction of NO driven by photosynthesis and catalyzed by flavodiiron proteins, the dark N2O production being catalyzed by a cytochrome p450. Both mechanisms of N2O production are present in chlorophytes, but absent from diatoms. Our study provides an unprecedented mechanistic understanding of N2O production by microalgae, allowing a better assessment of N2O-producing hot spots in aquatic environments. Nitrous oxide (N2O), a potent greenhouse gas in the atmosphere, is produced mostly from aquatic ecosystems, to which algae substantially contribute. However, mechanisms of N2O production by photosynthetic organisms are poorly described. Here we show that the green microalga Chlamydomonas reinhardtii reduces NO into N2O using the photosynthetic electron transport. Through the study of C. reinhardtii mutants deficient in flavodiiron proteins (FLVs) or in a cytochrome p450 (CYP55), we show that FLVs contribute to NO reduction in the light, while CYP55 operates in the dark. Both pathways are active when NO is produced in vivo during the reduction of nitrites and participate in NO homeostasis. Furthermore, NO reduction by both pathways is restricted to chlorophytes, organisms particularly abundant in ocean N2O-producing hot spots. Our results provide a mechanistic understanding of N2O production in eukaryotic phototrophs and represent an important step toward a comprehensive assessment of greenhouse gas emission by aquatic ecosystems. | https://doi.org/10.1073/pnas.1915276117 | Lower high school; Middle school; Upper high school |
Energy-And-Climate Articles; Water-Resources Articles | How do tiny ocean critters affect the global carbon cycle | Carbon is the elemental building block for all living things. Over time, carbon moves through the land, air, and oceans in a process called the carbon cycle. Parts of the oceanic carbon cycle are still a mystery. How do tiny photosynthetic microbes and bacteria in the ocean affect the carbon cycle? Why does some carbon stay in the ocean for thousands of years while other carbon moves from the ocean to the air in just seconds or minutes? By combining new methods from chemistry, biology, and data management, we are investigating carbon dissolved in seawater. Eventually, wed like to understand how bacteria in the ocean will react to our changing climate will they help store more carbon safely in the ocean or will they speed climate change by adding more carbon to the atmosphere? | Dissolved organic matter (DOM) in the oceans is one of the largest pools of reduced carbon on Earth, comparable in size to the atmospheric CO2 reservoir. A vast number of compounds are present in DOM, and they play important roles in all major element cycles, contribute to the storage of atmospheric CO2 in the ocean, support marine ecosystems, and facilitate interactions between organisms. At the heart of the DOM cycle lie molecular-level relationships between the individual compounds in DOM and the members of the ocean microbiome that produce and consume them. In the past, these connections have eluded clear definition because of the sheer numerical complexity of both DOM molecules and microorganisms. Emerging tools in analytical chemistry, microbiology, and informatics are breaking down the barriers to a fuller appreciation of these connections. Here we highlight questions being addressed using recent methodological and technological developments in those fields and consider how these advances are transforming our understanding of some of the most important reactions of the marine carbon cycle. | http://www.pnas.org/content/113/12/3143.full.pdf | Lower high school; Upper high school |
Energy-And-Climate Articles; Water-Resources Articles | How does carbon cycle through the oceans | Imagine you were a detective following a carbon dioxide (CO2) molecule, for instance, one of the millions you just exhaled. Where does it go? Up away into the atmosphere? Is it used by a plant to build a green leaf? Guess what: a lot of the carbon we (and our cars and factories) exhale actually ends up in the ocean. So get ready to get wet! Once in the ocean, the CO2 molecule might hang around in the surface for a short while before jumping back to the air above, or it might travel deep down to the bottom of the ocean where it stays trapped for hundreds of years. We created a computer model (a type of virtual ocean) to act like such a detective, tracking CO2 in the ocean to discover where it goes and how long it will stay. We found that carbon cycles very differently in different latitudes of the ocean. This was not known before and provides important clues about how the ocean will respond to, and contribute to, global climate change. | The transfer efficiency of sinking organic particles through the mesopelagic zone and into the deep ocean is a critical determinant of the atmosphere?ocean partition of carbon dioxide (CO2). Our ability to detect large-scale spatial variations in transfer efficiency is limited by the scarcity and uncertainties of particle flux data. Here we reconstruct deep ocean particle fluxes by diagnosing the rate of nutrient accumulation along transport pathways in a data-constrained ocean circulation model. Combined with estimates of organic matter export from the surface, these diagnosed fluxes reveal a global pattern of transfer efficiency to 1,000 m that is high (?25%) at high latitudes and low (?5%) in subtropical gyres, with intermediate values in the tropics. This pattern is well correlated with spatial variations in phytoplankton community structure and the export of ballast minerals, which control the size and density of sinking particles. These findings accentuate the importance of high-latitude oceans in sequestering carbon over long timescales, and highlight potential impacts on remineralization depth as phytoplankton communities respond to a warming climate. | http://www.pnas.org/content/113/31/8606.abstract | Lower high school; Upper high school |
Energy-And-Climate Articles; Social-Science Articles | How does climate change affect poor people in Africa | Our planet is warming up! That doesnt mean we will have We studied one of the poorest regions in the world, nicer weather, though. It means we have weather events sub-Saharan Africa (SSA). We analyzed data from thousands that are more extreme. Floods, droughts, and heatwaves are of families living all across the continent and looked at what more powerful and are happening more often. People lose happens to them when extreme weather events occur. We their homes, jobs, and eat less food. And poor people suffer found that floods had a worse impact than heatwaves and the most! People who are very poor do not have enough droughts. Finally, we predicted that because of climate resources to handle the effects of extreme weather events. change, the number of people living in poverty there could To help them in the future, we need a good understanding increase in years. Our results could be very useful for of what is happening now. planning ways to help people in Africa. | To estimate the effects of weather conditions on welfare globally, cross-country comparisons need to rely on international poverty lines and comparable data sources at the micro-level. To this end, nationally representative household surveys can offer a useful instrument, also at the sub-national level. This study seeks to expand the existing knowledge on the determinants of poverty in Africa south of the Sahara (SSA), examining how long-term climatic conditions and year-specific weather shocks affect expenditure per capita. We take advantage of a novel and unique dataset combining consumption-based household surveys for 24 SSA countries -representative of more than half of the African population and two thirds of SSA- and geospatial information on agro-climatic conditions, market access and other spatial covariates of poverty. To our knowledge, it is the first time that a welfare-based, multidisciplinary, micro-level dataset with such wide spatial coverage has been assembled and examined. Our analysis relies on a linear and spatial model at the household- and district-level, respectively, both controlling for socio-economic, demographic, and geographic confounding factors. Results are consistent across econometric approaches, showing that living in more humid areas is positively associated with welfare, while the opposite occurs living in hotter areas, as existing literature shows. Flood shocks -defined as annual rainfall higher than one standard deviation from the 50-year average- are associated to a 35% decrease in total and food per-capita consumption and 17 percentage point increase in extreme poverty. On the other hand, extreme shortages of rain and heat shocks show an uncertain effect, even when estimates control for spatial correlation between welfare and weather conditions using the spatial error correction model. Given the heterogeneous effects of climatic events across SSA macro-regions, local-specific adaptation and mitigation strategies are suggested to help bringing households on a sustainable path. | https://doi.org/10.1016/j.worlddev.2019.104691 | Middle school |
Energy-And-Climate Articles; Food-And-Agriculture Articles | How hot can corn handle it | Can you remember ever feeling the sun blazing down on your head so fiercely it felt like you might melt? How do you think plants cope with this heat?Scientists have previously thought that high air temperatures are limiting corn yields. They predict that as temperatures rise, this will cause significant losses. But are they right? To answer this, we looked at irrigated corn yield data from three states in the western US Corn Belt. We found that the genetics of the crop and the crop management techniques explained differences in yield more than climate. These factors really changed the corns response to the temperature. Our findings can help farmers adapt to rising temperatures. Studies predict that by the year 2050, demand for corn will grow by 50% in the developing world and that the average global temperature will increase by roughly 2C at this time. | Several recent studies have indicated that high air temperatures are limiting maize (Zea mays L.) yields in the US Corn Belt and project significant yield losses with expected increases in growing season temperatures. Further work has suggested that high air temperatures are indicative of high evaporative demand, and that decreases in maize yields which correlate to high temperatures and vapor pressure deficits (VPD) likely reflect underlying soil moisture limitations. It remains unclear whether direct high temperature impacts on yields, independent of moisture stress, can be observed under current temperature regimes. Given that projected high temperature and moisture may not co-vary the same way as they have historically, quantitative analyzes of direct temperature impacts are critical for accurate yield projections and targeted mitigation strategies under shifting temperature regimes. To evaluate yield response to above optimum temperatures independent of soil moisture stress, we analyzed climate impacts on irrigated maize yields obtained from the National Corn Growers Association (NCGA) corn yield contests for Nebraska, Kansas and Missouri. In irrigated maize, we found no evidence of a direct negative impact on yield by daytime air temperature, calculated canopy temperature, or VPD when analyzed seasonally. Solar radiation was the primary yield-limiting climate variable. Our analyses suggested that elevated night temperature impacted yield by increasing rates of phenological development. High temperatures during grain-fill significantly interacted with yields, but this effect was often beneficial and included evidence of acquired thermo-tolerance. Furthermore, genetics and managementinformation uniquely available in the NCGA contest dataexplained more yield variability than climate, and significantly modified crop response to climate. Thermo-acclimation, improved genetics and changes to management practices have the potential to partially or completely offset temperature-related yield losses in irrigated maize. | http://iopscience.iop.org/article/10.1088/1748-9326/11/9/094012/meta | Lower high school; Upper high school |
Energy-And-Climate Articles | How is the ice in Greenland melting | The island of Greenland is almost completely covered in ice. We needed lots of data (information) to be able to answer But since the 1990s, the sheet of ice has been melting. This these questions. So we collected data to help us model the makes the sea level rise, causing problems for people and ice sheet melt. We looked at glaciers all around the coast animals around the world who live on the coast. of Greenland. We found out most of the melt was happening with glaciers in deep, underwater valleys. Here, the warm We wanted to find out exactly how the Greenland ice sheet ocean melted the glaciers from below. Our findings are is melting. Does the ocean affect how quickly it melts? Could important for predicting the future of Greenlands ice. it be melting Greenlands ice from below? | The retreat and acceleration of Greenland glaciers since the mid-1990s have been attributed to the enhanced intrusion of warm Atlantic Waters (AW) into fjords, but this assertion has not been quantitatively tested on a Greenland-wide basis or included in models. Here, we investigate how AW influenced retreat at 226 marine-terminating glaciers using ocean modeling, remote sensing, and in situ observations. We identify 74 glaciers in deep fjords with AW controlling 49% of the mass loss that retreated when warming increased undercutting by 48%. Conversely, 27 glaciers calving on shallow ridges and 24 in cold, shallow waters retreated little, contributing 15% of the loss, while 10 glaciers retreated substantially following the collapse of several ice shelves. The retreat mechanisms remain undiagnosed at 87 glaciers without ocean and bathymetry data, which controlled 19% of the loss. Ice sheet projections that exclude ocean-induced undercutting may underestimate mass loss by at least a factor of 2. | https://www.science.org/doi/10.1126/sciadv.aba7282 | Lower high school; Middle school |
Energy-And-Climate Articles; Food-And-Agriculture Articles | How much does it cost when cows burp | What do cow burps have to do with climate change or the price pound of wheat. And most of this carbon comes from cow burps! of meat? Scientists say that the climate on the planet is changing Climate change is pretty expensive for us: for example, having because of an extra layer of carbon in the Earths atmosphere. to pay for houses and road reconstruction after super destructive As it happens, all our activities release carbon taking the bus to storms. As a result, some people are suggesting we should school, charging your laptop, and even eating! Especially eating charge ourselves a small fee for doing things that release a lot of beef. Scientists have calculated that producing pound of beef carbon. If this happens, both wheat and beef will become a little', 'results': 'more expensive. But the increase in beef prices will be higher. | The US food system utilizes large quantities of liquid fuels, electricity, and chemicals yielding significant greenhouse gas (GHG) emissions that are not considered in current retail prices, especially when the contribution of biogenic emissions is considered. However, because GHG emissions might be assigned a price in prospective climate policy frameworks, it would be useful to know the extent to which those policies would increase the incremental production costs to food within the US food system. This analysis uses lifecycle assessment (LCA) to (1) estimate the magnitude of carbon dioxide equivalent (CO2e) emissions from typical US food production practices, using wheat and beef as examples, and (2) quantify the cost of those emissions in the context of a GHG-pricing regime over a range of policy constructs. Wheat and beef were chosen as benchmark staples to provide a representative range of less intensive and more intensive agricultural goods, respectively. Results suggest that 1.1 0.13 and 31 8.1 kg of lifecycle CO2e emissions are embedded in 1 kg of wheat and beef production, respectively. Consequently, the cost of lifecycle CO2e emissions for wheat (i.e. cultivation, processing, transportation, storage, and end-use preparation) over an emissions price range of $10 and $85 per tonne CO2e is estimated to be between $0.01 and $0.09 per kg of wheat, respectively, which would increase total wheat production costs by approximately 0.32% per kg. By comparison, the estimated lifecycle CO2e price of beef over the same range of CO2e prices is between $0.31 and $2.60 per kg of beef, representing a total production cost increase of approximately 540% per kg based on average 2010 food prices. This range indicates that the incremental cost to total US food production might be anywhere between $0.635.4 Billion per year for grain and $3.70 and $32 Billion per year for beef based on CO2e emissions assuming that total production volumes stay the same. | http://www.animalfeedscience.com/article/S0377-8401(11)00120-9/abstract?cc=y= | Lower high school; Middle school |
Energy-And-Climate Articles; Water-Resources Articles | How much money is stored under our feet | For over 100 years, scientists and economists have struggled to figure out how much money our natural resources are worth when left untapped in Nature. We addressed this problem by creating a new formula to measure the value, in money terms, of leaving natural resources in place. We then picked a case study (a real-life example) to illustrate our formulas: we investigated an agricultural area in western Kansas that grows crops using groundwater. These underground water resources are stored in the High Plains Aquifer. We thought of the aquifer like a bank account and asked how much money Kansas pulled out of its groundwater bank account over a period of 10 years. The number turned out to be large: $110 million per year, which is more than twice the amount Kansas spent on schools in that time! Our study shows that we have to take the value of Nature into account when planning how to use its resources in order to make wise and sustainable investments for our future. | Valuing natural capital is fundamental to measuring sustainability. The United Nations Environment Programme, World Bank, and other agencies have called for inclusion of the value of natural capital in sustainability metrics, such as inclusive wealth. Much has been written about the importance of natural capital, but consistent, rigorous valuation approaches compatible with the pricing of traditional forms of capital have remained elusive. We present a guiding quantitative framework enabling natural capital valuation that is fully consistent with capital theory, accounts for biophysical and economic feedbacks, and can guide interdisciplinary efforts to measure sustainability. We illustrate this framework with an application to groundwater in the Kansas High Plains Aquifer, a rapidly depleting asset supporting significant food production. We develop a 10-y time series (1996?2005) of natural capital asset prices that accounts for technological, institutional, and physical changes. Kansas lost approximately $110 million per year (2005 US dollars) of capital value through groundwater withdrawal and changes in aquifer management during the decade spanning 19962005. This annual loss in wealth is approximately equal to the states 2005 budget surplus, and is substantially more than investments in schools over this period. Furthermore, real investment in agricultural capital also declined over this period. Although Kansas depletion of water wealth is substantial, it may be tractably managed through careful groundwater management and compensating investments in other natural and traditional assets. Measurement of natural capital value is required to inform management and ongoing investments in natural assets. | https://www.pnas.org/doi/abs/10.1073/pnas.1513779113 | Lower high school; Upper high school |
Energy-And-Climate Articles; Social-Science Articles | How well do climate laws help reduce global warming | The worlds response to climate change has been weak, but more than nothing. There are hundreds of climate change laws in countries around the world but how good are they at tackling the problem? We wanted to find out how well these laws are working. We used a database with information about climate laws in 133 countries across the globe. We found that each new law reduces yearly carbon dioxide emissions by an average of 0.8% in the first 3 years, and 1.8% in the longer term. Some types of laws are better than others at reducing emissions. How well a country can implement a new law is also important! Some are much better at implementing laws, which means they are more likely to reduce emissions. We need to work together to create stronger laws to solve this global problem. | The international response to climate change has been inadequate, but not zero. There are 1,800 climate change laws worldwide. We use panel data on legislative activity in 133 countries over the period 19992016 to identify statistically the short-term and long-term impact of climate legislation. Each new law reduces annual carbon dioxide (CO2) emissions per unit of gross domestic product by 0.78% nationally in the short term (during the first three years) and by 1.79% in the long term (beyond three years). The results are driven by parliamentary acts and by countries with a strong rule of law. In 2016, current climate laws were associated with an annual reduction in global CO2emissions of 5.9?GtCO2, more than the US CO2output that year. Cumulative CO2emissions savings from 1999 to 2016 amount to 38?GtCO2, or one years worth of global CO2output. The impact on other greenhouse gases is much lower. | https://doi.org/10.1038/s41558-020-0831-z | Lower high school; Middle school |
Energy-And-Climate Articles; Social-Science Articles | More stuff more climate change | Imagine living in an area where it starts getting uncomfortably hot. Would you and your family just pack up and move somewhere else to be more comfortable? Unlike people, trees cannot escape to other climates quickly when temperatures rise as a result of global climate change. Will they suffer when it gets hotter? Or would they benefit instead? We wanted to understand how trees in northern (or boreal) forests would respond to rising temperatures. We analyzed results from transplant experiments that took seeds from one area and planted them in areas with different climates. We found that where a tree is located within its geographical range determines how it will be affected: trees growing in the northern part of their range will likely benefit from rising temperatures and grow faster, but trees growing in the southern part of their range will likely grow more slowly. Keep in mind that factors other than just temperature changes also have to be considered to understand how forests will respond to climate change. | While the EU Commission has encouraged Member States to combine national and international climate change mitigation measures with subnational environmental policies, there has been little harmonized effort towards the quantification of embodied greenhouse gas (GHG) emissions from household consumption across European regions. This study develops an inventory of carbon footprints associated with household consumption for 177 regions in 27 EU countries, thus, making a key contribution for the incorporation of consumption-based accounting into local decision-making. Footprint calculations are based on consumer expenditure surveys and environmental and trade detail from the EXIOBASE 2.3 multiregional input-output database describing the world economy in 2007 at the detail of 43 countries, 5 rest-of-the-world regions and 200 product sectors. Our analysis highlights the spatial heterogeneity of embodied GHG emissions within multiregional countries with subnational ranges varying widely between 0.6 and 6.5 tCO2e/cap. The significant differences in regional contribution in terms of total and per capita emissions suggest notable differences with regards to climate change responsibility. The study further provides a breakdown of regional emissions by consumption categories (e.g. housing, mobility, food). In addition, our region-level study evaluates driving forces of carbon footprints through a set of socio-economic, geographic and technical factors. Income is singled out as the most important driver for a region's carbon footprint, although its explanatory power varies significantly across consumption domains. Additional factors that stand out as important on the regional level include household size, urban-rural typology, level of education, expenditure patterns, temperature, resource availability and carbon intensity of the electricity mix. The lack of cross-national region-level studies has so far prevented analysts from drawing broader policy conclusions that hold beyond national and regional borders. | http://iopscience.iop.org/article/10.1088/1748-9326/aa6da9 | Lower high school; Upper high school |
Energy-And-Climate Articles; Pollution Articles | Nuclear waste fuel of the future | Nuclear power has the potential to be a climate-friendly can run on existing nuclear waste. And here is the good energy source, but also embodies great threats to humans news: our feasibility study shows that it can be done, and the environment which requires dedicated safety and that the majority of current nuclear waste does not precautions. Currently, safely handling large amounts of even have to be modified. These advanced nuclear power very long lived, dangerous radioactive waste created by stations do not yet exist. However, with a focus on the nuclear power production makes it a pretty costly and generation of sustainable and climate-friendly energy in unsustainable endeavor. In this study, we analyze if it is our research and development efforts, we believe we can possible to redesign nuclear power stations so that they make them happen in the near future. | A solution for the nuclear waste problem is the key challenge for an extensive use of nuclear reactors as a major carbon free, sustainable, and applied highly reliable energy source. Partitioning and Transmutation (P&T) promises a solution for improved waste management. Current strategies rely on systems designed in the 60s for the massive production of plutonium. We propose an innovative strategic development plan based on invention and innovation described with the concept of developments in s-curves identifying the current boundary conditions, and the evolvable objectives. This leads to the ultimate, universal vision for energy production characterized by minimal use of resources and production of waste, while being economically affordable and safe, secure and reliable in operation. This vision is transformed into a mission for a disruptive development of the future nuclear energy system operated by burning of existing spent nuclear fuel (SNF) without prior reprocessing. This highly innovative approach fulfils the sustainability goals and creates new options for P&T. A proof on the feasibility from neutronic point of view is given demonstrating sufficient breeding of fissile material from the inserted SNF. The system does neither require new resources nor produce additional waste, thus it provides a highly sustainable option for a future nuclear system fulfilling the requests of P&T as side effect. In addition, this nuclear system provides enhanced resistance against misuse of Pu and a significantly reduced fuel cycle. However, the new system requires a demand driven rethinking of the separation process to be efficient. | http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0180703 | Lower high school; Upper high school |
Energy-And-Climate Articles; Water-Resources Articles | The Arctic is melting so what | The Arctic sea ice over the North Pole is melting faster than humans have ever witnessed as a result of climate change. How does this affect the weather elsewhere, though? Does it? We wanted to know if people outside the Polar Circle would experience more extreme weather as a result of the melting. We entered predictions for sea ice loss as input into a climate model. The goal was to estimate the number of warm, cold, wet, and dry days as a result of the melted ice. According to the model, in more northern locations, like Siberia, Scandinavia, and northern North America, people would experience fewer cold days and more warm days. In addition, Eastern U.S., Central Europe, Siberia, and all of Asia can expect fewer dry days while the Mediterranean, Siberia and northern North America will face more wet days. Lots of changes in store, right? And not just in the Arctic! | The decline in Arctic sea ice cover has been widely documented and it is clear that this change is having profound impacts locally. An emerging and highly uncertain area of scientific research, however, is whether such Arctic change has a tangible effect on weather and climate at lower latitudes. Of particular societal relevance is the open question: will continued Arctic sea ice loss make mid-latitude weather more extreme? Here we analyse idealized atmospheric general circulation model simulations, using two independent models, both forced by projected Arctic sea ice loss in the late twenty-first century. We identify robust projected changes in regional temperature and precipitation extremes arising solely due to Arctic sea ice loss. The likelihood and duration of cold extremes are projected to decrease over high latitudes and over central and eastern North America, but to increase over central Asia. Hot extremes are projected to increase in frequency and duration over high latitudes. The likelihood and severity of wet extremes are projected to increase over high latitudes, the Mediterranean and central Asia; and their intensity is projected to increase over high latitudes and central and eastern Asia. The number of dry days over mid-latitude Eurasia and dry spell duration over high latitudes are both projected to decrease. There is closer model agreement for projected changes in temperature extremes than for precipitation extremes. Overall, we find that extreme weather over central and eastern North America is more sensitive to Arctic sea ice loss than over other mid-latitude regions. Our results are useful for constraining the role of Arctic sea ice loss in shifting the odds of extreme weather, but must not be viewed as deterministic projections, as they do not account for drivers other than Arctic sea ice loss. | http://blogs.ei.columbia.edu/2010/08/26/a-beginners-guide-to-climate-models/ | Lower high school; Middle school |
Energy-And-Climate Articles; Pollution Articles | Waste to Energy How can we get the most from our waste | What is in your waste bin? Banana peels, used napkins, a There are four types of waste biomass. Different waste broken pencil? You may think they are useless waste. But conversion technologies turn it into energy. We wanted theyre not: they are waste biomass! They are made of once- to know which combination would give us the maximum living things and they store energy. We can convert that benefits. We found that we can gain lots of energy back energy into other forms and use it to light a reading lamp, from waste to help the environment. However, the right type cook a meal, or as fuel in our cars. Using waste instead of of waste and conversion technology could be different for fossil fuels reduces air and water pollution as well. The best each part of the USA. part is that we already produce so much waste, so why not use it? | Agricultural and forestry residues, animal manure and municipal solid waste are replenishable and widely available. However, harnessing these heterogeneous and diffuse resources for energy requires a holistic assessment of alternative conversion pathways, taking into account spatial factors. Here, we analyse, from a life-cycle assessment perspective, the potential renewable energy production, net energy gain and greenhouse gas (GHG) emission reduction for each distinct type of waste feedstock under different conversion technology pathways. The utilization of all available wastes and residues in the contiguous United States can generate 3.13.8 exajoules (EJ) of renewable energy, but only deliver 2.43.2?EJ of net energy gain, and displace 103178 million tonnes of CO2-equivalent GHG emissions. For any given waste feedstock, looking across all US counties where it is available, except in rare instances, no single conversion pathway simultaneously maximizes renewable energy production, net energy gain and GHG mitigation. | https://doi.org/10.1038/s41560-019-0430-2 | Lower high school; Middle school |
Energy-And-Climate Articles | What do trees know about rain | Did you know that Australia was the driest inhabited continent in the world? How ironic is it then that in the past 20 years, Aussies have been experiencing quiet a lot of rain? In fact, in some places it rained more than at any time in the past 200 hundred years! But how do we know how much it rained in the early 1800s? At that time the Brits had barely just started colonizing the continent! They definitely didnt bother setting up rain gauges! The answers come from the trees! By taking a core from old native trees and carefully studying the annual tree rings, scientists can work out how much it rained in 1802! Whats more important, though, is that the last two decades turn out to be unusually wet compared to the previous two centuries. In the one hundred and ninety years from 1800 to 1990 there were only two years when it rained more than 20 inches. By contrast, in four out of the past 20 years alone, it rained that much (and more). What is causing this? | An understanding of past hydroclimatic variability is critical to resolving the significance of recent recorded trends in Australian precipitation and informing climate models. Our aim was to reconstruct past hydroclimatic variability in semi-arid northwest Australia to provide a longer context within which to examine a recent period of unusually high summer-autumn precipitation. We developed a 210-year ring-width chronology from Callitris columellaris, which was highly correlated with summer-autumn (DecMay) precipitation (r = 0.81; 19102011; p < 0.0001) and autumn (MarMay) self-calibrating Palmer drought severity index (scPDSI, r = 0.73; 19102011; p < 0.0001) across semi-arid northwest Australia. A linear regression model was used to reconstruct precipitation and explained 66% of the variance in observed summer-autumn precipitation. Our reconstruction reveals inter-annual to multi-decadal scale variation in hydroclimate of the region during the last 210 years, typically showing periods of below average precipitation extending from one to three decades and periods of above average precipitation, which were often less than a decade. Our results demonstrate that the last two decades (19952012) have been unusually wet (average summer-autumn precipitation of 310 mm) compared to the previous two centuries (average summer-autumn precipitation of 229 mm), coinciding with both an anomalously high frequency and intensity of tropical cyclones in northwest Australia and the dominance of the positive phase of the Southern Annular Mode. | https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0128533 | Lower high school |
Energy-And-Climate Articles | What is going on in the tropical stratosphere | Have you ever noticed that the clouds above you are moving westward to eastward, then back again starting from the very fast, even though you dont feel any wind where you are middle of the stratosphere, then working its way down. standing on the ground? Thats because wind blows at different Or at least thats how it usually works! This past winter, we speeds and directions at different altitudes in the atmosphere. noticed a curious change in this normal downward progression The quasi-biennial oscillation is a slow change in wind direction of the quasi-biennial oscillation. Instead of the eastward from eastward to westward that occurs high in the atmosphere blowing winds slowly moving down through the atmosphere, above the tropics (the latitudes close to the equator). Over the westward blowing winds suddenly started moving upward! about a two-year period, the wind direction switches from This has never been observed before! | The quasi-biennial oscillation (QBO) is a tropical lower stratospheric, downward propagating zonal wind variation, with an average period of ~28?months. The QBO has been constantly documented since 1953. Here we describe the evolution of the QBO during the Northern Hemisphere winter of 20152016 using radiosonde observations and meteorological reanalyses. Normally, the QBO would show a steady downward propagation of the westerly phase. In 20152016, there was an anomalous upward displacement of this westerly phase from ~30?hPa to 15?hPa. These westerlies impinge on or cutoff the normal downward propagation of the easterly phase. In addition, easterly winds develop at 40?hPa. Comparisons to tropical wind statistics for the 1953 to present record demonstrate that this 20152016 QBO disruption is unprecedented. | http://onlinelibrary.wiley.com/doi/10.1002/2016GL070373/abstract | Upper high school |
Energy-And-Climate Articles | Why are the Himalayas getting hotter | Reaching almost nine kilometers (, feet) up into the rates of warming, and that the rate of warming is likely to sky, Mount Everest (Fig.) is the tallest and most famous further increase by the end of this century. This could have mountain in the world. It belongs to a mountain chain called serious consequences for people around the world. the Himalayas, which sits on the border of several countries in Southeast Asia. We carried out a study looking at the climate of the Himalayas, a neighbouring mountain range (the Karakoram), and the Figure : Tibetan Plateau. Mount Everest is so high that We used data from climate models to investigate temperature its peak is in changes, and their relationship to altitude (height above sea the Jet Stream! level). We found that higher altitudes experienced greater The wind can blow over km/h ( mph) at the summit. | We use the output of twenty-seven Global Climate Models participating in the Coupled Model Intercomparison Project phase 5 (CMIP5) to investigate the temperature changes and their dependence on the elevation in the Tibetan Plateau, Himalaya and Karakoram mountains and in the surrounding areas in historical model simulations and in future projections. The aim of this study is to explore if and to what extent the CMIP5 models show elevation-dependent warming (EDW) in this part of the globe and to investigate what are the driving factors at play and their relative importance. Our results indicate that the models show enhanced rates of warming at higher elevations in the Tibetan Plateau-Himalayan region in the twentieth century, and this phenomenon is projected to strengthen by the end of the twenty-first century under a high-emission scenario. We find a nonlinear relationship between the warming rates and the elevation, for both the minimum and the maximum temperature: regions with temperatures below the freezing level of water show more warming than the regions with temperatures above, likely suggesting a key role of mechanisms involving water phase changes, the presence/absence of snow and the snow-albedo feedback. We consider the main variables simulated by the CMIP5 models whose change may be related to temperature changes at higher elevations. We find that changes in surface albedo, atmospheric humidity and downward longwave radiation are relevant factors for EDW in the Tibetan Plateau-Himalayas, with surface albedo being the leading driver. | https://link.springer.com/article/10.1007/s00382-016-3316-z | Lower high school; Upper high school |
Energy-And-Climate Articles; Water-Resources Articles | Why is New Orleans sinking | Imagine living in a city where the ground is slowly sinking under your feet. Now picture this city below sea level, surrounded by water, and kept dry by a system of surrounding walls (levees). This is normal life for residents of New Orleans, a city of over 350,000 people in the US state of Louisiana built on the original floodplain of the Mississippi River. Previous studies showed that New Orleans is slowly sinking into the ground, increasing an already high flood risk from storms like Hurricane Katrina. Is that really the case? And if so, at what rate is it sinking? We set out to answer these important questions by using improved radar technology. We further investigated to what extent natural or human processes contribute to the sinking of the city. Our results show that sinking is real and in some areas worse than previously measured. We also found that human actions mainly pumping of ground and surface water are worsening the situation. | New measurements of ongoing subsidence of land proximal to the city of New Orleans, Louisiana, and including areas around the communities of Norco and Lutcher upriver along the Mississippi are reported. The rates of vertical motion are derived from interferometric synthetic aperture radar (InSAR) applied to Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) data acquired on 16 June 2009 and 2 July 2012. The subsidence trends are similar to those reported for 20022004 in parts of New Orleans where observations overlap, in particular in Michoud, the 9th Ward, and Chalmette, but are measured at much higher spatial resolution (6?m). The spatial associations of cumulative surface movements suggest that the most likely drivers of subsidence are groundwater withdrawal and surficial drainage/dewatering activities. High subsidence rates are observed localized around some major industrial facilities and can affect nearby flood control infrastructure. Substantial subsidence is observed to occur rapidly from shallow compaction in highly localized areas, which is why it could be missed in subsidence surveys relying on point measurements at limited locations. | http://onlinelibrary.wiley.com/doi/10.1002/2015JB012636/full | Lower high school; Upper high school |
Energy-And-Climate Articles; Technology Articles | Will artificial trees be the next power plants | Wind power is an important source of renewable energy, but some people are concerned that conventional wind turbines are too loud and too hazardous for birds and bats. We wanted to create a new kind of wind energy harvesting machine based on the jiggling motion of cottonwood tree leaves in the wind, which would be quieter and safer for wildlife. After building and testing artificial cottonwood leaves that moved and created electricity in the wind, we found that they didnt produce enough energy to feasibly use for electricity production. We also tried building a cattail-like device to generate electricity when it swayed in the wind, but it also didnt produce enough energy to make it reasonable to use. Though our research showed that artificial plants jiggling or swaying isnt likely to be a cost-effective way to produce electricity, we think it could be fruitful to look into other plant-inspired designs for harvesting wind energy. We also are testing a previously unexploited biological material known to convert mechanical to electrical energy far more effectively than the ones used today. | In 2008 the U.S. Department of Energy set a target of 20% wind energy by 2030. To date, induction-based turbines form the mainstay of this effort, but turbines are noisy, perceived as unattractive, a potential hazard to bats and birds, and their height hampers deployment in residential settings. Several groups have proposed that artificial plants containing piezoelectric elements may harvest wind energy sufficient to contribute to a carbon-neutral energy economy. Here we measured energy conversion by cottonwood-inspired piezoelectric leaves, and by a vertical flapping stalkthe most efficient piezo-leaf previously reported. We emulated cottonwood for its unusually ordered, periodic flutter, properties conducive to piezo excitation. Integrated over 090 (azimuthal) of incident airflow, cottonwood mimics outperformed the vertical flapping stalk, but they produced << daW per conceptualized tree. In contrast, a modest-sized cottonwood tree may dissipate ~ 80 W via leaf motion alone. A major limitation of piezo-transduction is charge generation, which scales with capacitance (area). We thus tested a rudimentary, cattail-inspired leaf with stacked elements wired in parallel. Power increased systematically with capacitance as expected, but extrapolation to acre-sized assemblages predicts << daW. Although our results suggest that present piezoelectric materials will not harvest mid-range power from botanic mimics of convenient size, recent developments in electrostriction and triboelectric systems may offer more fertile ground to further explore this concept. | http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0170022 | Lower high school; Middle school |
Food-And-Agriculture Articles; Social-Science Articles | Can sub-Saharan Africa feed itself | By the year , the worlds population will need % Figure : more food than it did in . In sub-Saharan Africa (well Sub-Saharan Africa (SSA) is a region in the continent of Africa that lies in or below the Sahara desert. There are countries in SSA. call it SSA) (Fig. ) this problem will be even greater, with the demand for cereals increasing by more than three times as the population rises. We collected and calculated farming data for countries in sub-Saharan Africa. This made us realize that countries in SSA must make many large changes to increase their yield of cereals (the amount of cereals that are grown on the current farmland each year) to meet this greater demand. If countries in SSA are unable to increase cereal yield, there are two options. Either farmland areas will have to increase drastically, at the expense of natural land, or SSA will need to buy more cereal from other countries than it does today. This may put more people in these countries at risk of not having enough food to be able to live healthily. | Although global food demand is expected to increase 60% by 2050 compared with 2005/2007, the rise will be much greater in sub-Saharan Africa (SSA). Indeed, SSA is the region at greatest food security risk because by 2050 its population will increase 2.5-fold and demand for cereals approximately triple, whereas current levels of cereal consumption already depend on substantial imports. At issue is whether SSA can meet this vast increase in cereal demand without greater reliance on cereal imports or major expansion of agricultural area and associated biodiversity loss and greenhouse gas emissions. Recent studies indicate that the global increase in food demand by 2050 can be met through closing the gap between current farm yield and yield potential on existing cropland. Here, however, we estimate it will not be feasible to meet future SSA cereal demand on existing production area by yield gap closure alone. Our agronomically robust yield gap analysis for 10 countries in SSA using location-specific data and a spatial upscaling approach reveals that, in addition to yield gap closure, other more complex and uncertain components of intensification are also needed, i.e., increasing cropping intensity (the number of crops grown per 12 mo on the same field) and sustainable expansion of irrigated production area. If intensification is not successful and massive cropland land expansion is to be avoided, SSA will depend much more on imports of cereals than it does today. | http://www.pnas.org/content/113/52/14964.full | Lower high school; Upper high school |
Food-And-Agriculture Articles; Social-Science Articles | How can sharing knowledge better explain land use changes in Ethiopia | When you think about environmental issues, you probably think about science. How does science explain the problem? How can we use science to create a solution? Yet if we only think like scientists, we may miss important details. That is why we need to share knowledge with people who have different perspectives. We shared knowledge with local residents near the Guassa grassland in Ethiopia to discuss how land use had changed over time. They described how they use the land and the benefits it provides. Using satellite technology, we created maps of the area. We then shared these maps with the people of Guassa. Together, we found a link between soil problems and land use changes. We also determined how different management strategies affect land use. Because we shared knowledge with the local residents, we created a more complete picture of what is happening in Guassa. | Knowledge coproduction that draws on local and scientific knowledge presents opportunities for more holistic understanding of environmental change. We describe our use of a multiple-evidence based approach to investigate the causes and consequences of environmental change in a community-protected grassland and its surrounding landscape in the Ethiopian highlands. We explore the interaction of biophysical change (precipitation and vegetation) and social change (political and management institutions), and discuss potential impacts for ecosystem service provisioning. We quantified current distributions of locally defined land use/cover classes using a supervised classification, with an overall accuracy of 87.1%. Local community members then described and ranked the ecosystem services associated with each land class according to their perceived importance for society. Vegetation and precipitation changes were assessed using satellite time series beginning in the early 1980s, while local narratives describe changes back to the 1970s. The knowledge coproduction process brought together ethnographic and remote sensing approaches, revealing both complementary and contradictory findings across knowledge systems. Results with high agreement across knowledge systems clarify and reinforce understanding of certain threats and changes to the area, such as the rapidly declining native forests, the disappearing belg rainy season (p = 0.01), and the impact of insecure land tenure on natural resource extraction. Compelling areas of disagreement point to topics in need of further investigation, including increased attention to the spatial and temporal variability of change across a seemingly homogeneous cultural landscape, and the process of shrub encroachment into the protected grassland. | https://www.ecologyandsociety.org/vol25/iss2/art2/ | Lower high school |
Food-And-Agriculture Articles; Health-And-Medicine Articles; Pollution Articles | How does farming impact air quality | Farming releases small particles of pollution into the air. This lowers the quality of the surrounding air and has serious impacts on human health. In fact, air pollution caused by farming results in 17,900 deaths in the US every year! We wanted to understand more about which farming processes and foods caused the most pollution. That way we could look for ways to reduce it. We calculated the total farming-related air pollution released in the US. We broke this data down into different categories for further analysis. We found that animal waste, fertilizer, and tilling caused the vast majority of deaths. Animal-based foods caused nearly four times more deaths than plant-based foods. Finally, we looked at interventions that could decrease air pollution. We found that changes in diet were the most effective. But farming interventions alone could lower deaths considerably. | Agriculture is a major contributor to air pollution, the largest environmental risk factor for mortality in the United States and worldwide. It is largely unknown, however, how individual foods or entire diets affect human health via poor air quality. We show how food production negatively impacts human health by increasing atmospheric fine particulate matter (PM2.5), and we identify ways to reduce these negative impacts of agriculture. We quantify the air qualityrelated health damages attributable to 95 agricultural commodities and 67 final food products, which encompass >99% of agricultural production in the United States. Agricultural production in the United States results in 17,900 annual air qualityrelated deaths, 15,900 of which are from food production. Of those, 80% are attributable to animal-based foods, both directly from animal production and indirectly from growing animal feed. On-farm interventions can reduce PM2.5-related mortality by 50%, including improved livestock waste management and fertilizer application practices that reduce emissions of ammonia, a secondary PM2.5 precursor, and improved crop and animal production practices that reduce primary PM2.5 emissions from tillage, field burning, livestock dust, and machinery. Dietary shifts toward more plant-based foods that maintain protein intake and other nutritional needs could reduce agricultural air qualityrelated mortality by 68 to 83%. In sum, improved livestock and fertilization practices, and dietary shifts could greatly decrease the health impacts of agriculture caused by its contribution to reduced air quality. | https://www.pnas.org/doi/10.1073/pnas.2013637118 | Lower high school |
Food-And-Agriculture Articles; Health-And-Medicine Articles | How does the food you eat affect your growth and development | Hungry? Should you eat an apple or potato chips? Does it eating the wrong foods, and eating too much food all affect really matter? It turns out that what you eat as a child and the bodys systems. But the effects are different in each case. adolescent affects your growth and development. It can also We also learned that the negative effects of poor nutrition affect your health as an adult! We wanted to understand arent permanent if theyre corrected at the right time. the link between nutrition and adolescent growth. We did a review of different scientific studies to see what is currently known about this. We found that not eating enough food, | During adolescence, growth and development are transformative and have profound consequences on an individual's health in later life, as well as the health of any potential children. The current generation of adolescents is growing up at a time of unprecedented change in food environments, whereby nutritional problems of micronutrient deficiency and food insecurity persist, and overweight and obesity are burgeoning. In a context of pervasive policy neglect, research on nutrition during adolescence specifically has been underinvested, compared with such research in other age groups, which has inhibited the development of adolescent-responsive nutritional policies. One consequence has been the absence of an integrated perspective on adolescent growth and development, and the role that nutrition plays. Through late childhood and early adolescence, nutrition has a formative role in the timing and pattern of puberty, with consequences for adult height, muscle, and fat mass accrual, as well as risk of non-communicable diseases in later life. Nutritional effects in adolescent development extend beyond musculoskeletal growth, to cardiorespiratory fitness, neurodevelopment, and immunity. High rates of early adolescent pregnancy in many countries continue to jeopardise the growth and nutrition of female adolescents, with consequences that extend to the next generation. Adolescence is a nutrition-sensitive phase for growth, in which the benefits of good nutrition extend to many other physiological systems. | https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(21)01590-7/fulltext | Lower high school; Middle school |
Food-And-Agriculture Articles | What are the benefits of growing multiple crop species together | Did you know there are different ways to grow food? One way is sole cropping, which occurs when a field only has one species of crop. Another method is intercropping, which is when many species are grown together in the same field. We wanted to compare sole cropping and intercropping. We found that intercropping produces less of each type of crop on a field than sole cropping. But intercropping produces more diverse food choices. It also can save land space and reduce the amount of nitrogen fertilizer needed to grow food. That is why intercropping is an important agricultural technique to consider for the future. | Crop diversification has been put forward as a way to reduce the environmental impact of agriculture without penalizing its productivity. In this context, intercropping, the planned combination of two or more crop species in one field, is a promising practice. On an average, intercropping saves land compared with the component sole crops, but it remains unclear whether intercropping produces a higher yield than the most productive single crop per unit area, i.e., whether intercropping achieves transgressive overyielding. Here, we quantified the performance of intercropping for the production of grain, calories, and protein in a global meta-analysis of several production indices. The results show that intercrops outperform sole crops when the objective is to achieve a diversity of crop products on a given land area. However, when intercropping is evaluated for its ability to produce raw products without concern for diversity, intercrops on average generate a small loss in grain or calorie yield compared with the most productive sole crop (?4%) but achieve similar or higher protein yield, especially with maize/legume combinations grown at moderate N supply. Overall, although intercropping does not achieve transgressive overyielding on average, our results show that intercropping performs well in producing a diverse set of crop products and performs almost similar to the most productive component sole crop to produce raw products, while improving crop resilience, enhancing ecosystem services, and improving nutrient use efficiency. Our study, therefore, confirms the great interest of intercropping for the development of a more sustainable agricultural production, supporting diversified diets. | https://www.pnas.org/doi/10.1073/pnas.2201886120 | Lower high school; Middle school |
Food-And-Agriculture Articles; Health-And-Medicine Articles; Social-Science Articles | What makes you choose the food you eat | Have you ever thought about why you eat what you eat? Is it because its tasty? Healthy? Trendy? There are many factors that influence what an adolescent eats. But health is not always the most important one. We wanted to better understand these factors. So we did a scientific review of surveys and studies to see what adolescents eat worldwide. We also explored how economic status and food environment affect food choices. We learned that many adolescents value food as a way to express their individuality. It also gives them a sense of belonging with their peers. We also discovered that limited access to healthy food is a problem in many areas. So are advertisements promoting unhealthy food. That is why countries all over the world need nutrition programs that make healthy food more available, affordable, and appealing to adolescents. | Dietary intake during adolescence sets the foundation for a healthy life, but adolescents are diverse in their dietary patterns and in factors that influence food choice. More evidence to understand the key diet-related issues and the meaning and context of food choices for adolescents is needed to increase the potential for impactful actions. The aim of this second Series paper is to elevate the importance given to adolescent dietary intake and food choice, bringing a developmental perspective to inform policy and programmatic actions to improve diets. We describe patterns of dietary intake, then draw on existing literature to map how food choice can be influenced by unique features of adolescent development. Pooled qualitative data is then combined with evidence from the literature to explore ways in which adolescent development can interact with sociocultural context and the food environment to influence food choice. Irrespective of context, adolescents have a lot to say about why they eat what they eat, and insights into factors that might motivate them to change. Adolescents must be active partners in shaping local and global actions that support healthy eating patterns. Efforts to improve food environments and ultimately adolescent food choice should harness widely shared adolescent values beyond nutrition or health. | https://www.thelancet.com/journals/lancet/article/PIIS0140-6736%2821%2901687-1/fulltext | Lower high school; Middle school |
Health-And-Medicine Articles | Can HIV drugs help COVID-19 patients | Since its emergence in December , the new coronavirus We chose an anti-HIV treatment because it showed positive has killed tens of thousands of people. While social distancing results against other coronaviruses. A total of adults limits the spread of the disease, its not enough to end the with confirmed severe coronavirus infection participated in epidemic. Both vaccines and drugs are a great weapon our trial. Half of them received the anti-HIV treatment while against viruses, but they take a long time to create. This is the others served as a control group. We found that these why we turned to existing antiviral drugs. drugs werent particularly useful in patients with severe coronavirus infection. The treatment failed to speed up the patients improvement. It didnt reduce the viral load, either. | BACKGROUND No therapeutics have yet been proven effective for the treatment of severe illness caused by SARS-CoV-2. METHODS We conducted a randomized, controlled, open-label trial involving hospitalized adult patients with confirmed SARS-CoV-2 infection, which causes the respiratory illness Covid-19, and an oxygen saturation (Sao2) of 94% or less while they were breathing ambient air or a ratio of the partial pressure of oxygen (Pao2) to the fraction of inspired oxygen (Fio2) of less than 300 mm Hg. Patients were randomly assigned in a 1:1 ratio to receive either lopinavirritonavir (400 mg and 100 mg, respectively) twice a day for 14 days, in addition to standard care, or standard care alone. The primary end point was the time to clinical improvement, defined as the time from randomization to either an improvement of two points on a seven-category ordinal scale or discharge from the hospital, whichever came first. RESULTS A total of 199 patients with laboratory-confirmed SARS-CoV-2 infection underwent randomization; 99 were assigned to the lopinavirritonavir group, and 100 to the standard-care group. Treatment with lopinavirritonavir was not associated with a difference from standard care in the time to clinical improvement (hazard ratio for clinical improvement, 1.31; 95% confidence interval [CI], 0.95 to 1.80). Mortality at 28 days was similar in the lopinavirritonavir group and the standard-care group (19.2% vs. 25.0%; difference, ?5.8 percentage points; 95% CI, ?17.3 to 5.7). The percentages of patients with detectable viral RNA at various time points were similar. In a modified intention-to-treat analysis, lopinavirritonavir led to a median time to clinical improvement that was shorter by 1 day than that observed with standard care (hazard ratio, 1.39; 95% CI, 1.00 to 1.91). Gastrointestinal adverse events were more common in the lopinavirritonavir group, but serious adverse events were more common in the standard-care group. Lopinavirritonavir treatment was stopped early in 13 patients (13.8%) because of adverse events. CONCLUSIONS In hospitalized adult patients with severe Covid-19, no benefit was observed with lopinavirritonavir treatment beyond standard care. Future trials in patients with severe illness may help to confirm or exclude the possibility of a treatment benefit. (Funded by Major Projects of National Science and Technology on New Drug Creation and Development and others; | https://www.nejm.org/doi/full/10.1056/NEJMoa2001282 | Lower high school; Upper high school |
Health-And-Medicine Articles | Can medicine stop malaria | What comes to mind when you think of the most dangerous animals? Sharks? Tigers? How about mosquitoes? Mosquito bites are responsible for the deaths of around 400,000 people every year. The largest single cause of these deaths is malaria which can be a severe disease, caused by a tiny parasite carried by some mosquitoes. The current vaccine against malaria is only partially effective and not yet widely used so prevention mainly comes down to mosquito control (getting rid of mosquitoes from populated areas or preventing them from biting people). Another method for prevention being tried out in some places is to give drugs that kill the malaria parasite to large numbers of people. This technique is known as mass drug administration, shortened to MDA. Using mathematical models we wanted to find out when and where MDA works well. Our four models each predicted different levels of effectiveness for MDA, but overall we discovered the important factors that made MDA work better. Although MDA can be useful in malaria control programmes it still needs to be combined with good mosquito control. | Background Mass drug administration for elimination of Plasmodium falciparum malaria is recommended by WHO in some settings. We used consensus modelling to understand how to optimise the effects of mass drug administration in areas with low malaria transmission. Methods We collaborated with researchers doing field trials to establish a standard intervention scenario and standard transmission setting, and we input these parameters into four previously published models. We then varied the number of rounds of mass drug administration, coverage, duration, timing, importation of infection, and pre-administration transmission levels. The outcome of interest was the percentage reduction in annual mean prevalence of P falciparum parasite rate as measured by PCR in the third year after the final round of mass drug administration. Findings The models predicted differing magnitude of the effects of mass drug administration, but consensus answers were reached for several factors. Mass drug administration was predicted to reduce transmission over a longer timescale than accounted for by the prophylactic effect alone. Percentage reduction in transmission was predicted to be higher and last longer at lower baseline transmission levels. Reduction in transmission resulting from mass drug administration was predicted to be temporary, and in the absence of scale-up of other interventions, such as vector control, transmission would return to pre-administration levels. The proportion of the population treated in a year was a key determinant of simulated effectiveness, irrespective of whether people are treated through high coverage in a single round or new individuals are reached by implementation of several rounds. Mass drug administration was predicted to be more effective if continued over 2 years rather than 1 year, and if done at the time of year when transmission is lowest. Interpretation Mass drug administration has the potential to reduce transmission for a limited time, but is not an effective replacement for existing vector control. Unless elimination is achieved, mass drug administration has to be repeated regularly for sustained effect. | https://www.thelancet.com/journals/langlo/article/PIIS2214-109X(17)30220-6/fulltext | Lower high school; Middle school |
Health-And-Medicine Articles; Technology Articles | Can we detect HIV quickly and accurately from a drop of blood | HIV stands for human immunodeficiency virus a virus that This is why we wanted to create a cheap, portable, and makes your immune system weak so that it cannot fight off reliable method to detect HIV in the early stages of infection. infection. Its not easy to detect HIV in the first few weeks We were able to develop a small device that can rapidly detect after infection, but its actually very important so the person the virus from blood. This low-power, automated device can begin treatment and prevent transmission to another could be easily used by healthcare workers especially in person. areas with limited resources. | While identifying acute HIV infection is critical to providing prompt treatment to HIV-positive individuals and preventing transmission, existing laboratory-based testing methods are too complex to perform at the point of care. Specifically, molecular techniques can detect HIV RNA within 810 days of transmission but require laboratory infrastructure for cold-chain reagent storage and extensive sample preparation performed by trained personnel. Here, we demonstrate our point-of-care microfluidic rapid and autonomous analysis device (microRAAD) that automatically detects HIV RNA from whole blood. Inside microRAAD, we incorporate vitrified amplification reagents, thermally-actuated valves for fluidic control, and a temperature control circuit for low-power heating. Reverse transcription loop-mediated isothermal amplification (RT-LAMP) products are visualized using a lateral flow immunoassay (LFIA), resulting in an assay limit of detection of 100 HIV-1 RNA copies when performed as a standard tube reaction. Even after three weeks of room-temperature reagent storage, microRAAD automatically isolates the virus from whole blood, amplifies HIV-1 RNA, and transports amplification products to the internal LFIA, detecting as few as 3 ? 105HIV-1 viral particles, or 2.3 ? 107virus copies per mL of whole blood, within 90 minutes. This integrated microRAAD is a low-cost and portable platform to enable automated detection of HIV and other pathogens at the point of care. | https://pubs.rsc.org/en/content/articlehtml/2019/lc/c9lc00506d | Upper high school |
Health-And-Medicine Articles | Can we smell malaria | Malaria is one of the deadliest diseases in the world. People get infected through a mosquito bite after which the symptoms can vary from a mild feverish disease to a deadly one. There are some people though who dont develop any symptoms but they can still transmit malaria. This makes it more difficult to control the disease as there are more infected people out there than it appears. Other researchers have discovered that malaria can change peoples odor in order to attract mosquitoes. We wanted to see if we could use these changes to identify malaria cases.We collected odor and blood samples from approximately 400 children from Kenya. We observed different odor patterns in children who were infected with malaria and showed symptoms, those who were infected but did not have symptoms, and uninfected children. Using these patterns we were able to predict who has malaria and who does not, regardless of whether they showed symptoms. | Significance Malaria elimination efforts are hindered by the prevalence of asymptomatic infections, which frequently go undetected and untreated. Consequently, there is a pressing need for improved diagnostic screening methods. Based on extensive collections of skin odors from human populations in Kenya, we report broad and consistent effects of malaria infection on human volatile emissions. Furthermore, we found that predictive models based on machine learning algorithms reliably determined infection status based on volatile biomarkers and, critically, identified asymptomatic infections with 100% sensitivity, even in the case of low-level infections not detectable by microscopy. These findings suggest that volatile biomarkers have significant potential for the development of robust, noninvasive screening methods for detecting symptomatic and asymptomatic malaria infections under field conditions. Malaria remains among the worlds deadliest diseases, and control efforts depend critically on the availability of effective diagnostic tools, particularly for the identification of asymptomatic infections, which play a key role in disease persistence and may account for most instances of transmission but often evade detection by current screening methods. Research on humans and in animal models has shown that infection by malaria parasites elicits changes in host odors that influence vector attraction, suggesting that such changes might yield robust biomarkers of infection status. Here we present findings based on extensive collections of skin volatiles from human populations with high rates of malaria infection in Kenya. We report broad and consistent effects of malaria infection on human volatile profiles, as well as significant divergence in the effects of symptomatic and asymptomatic infections. Furthermore, predictive models based on machine learning algorithms reliably determined infection status based on volatile biomarkers. Critically, our models identified asymptomatic infections with 100% sensitivity, even in the case of low-level infections not detectable by microscopy, far exceeding the performance of currently available rapid diagnostic tests in this regard. We also identified a set of individual compounds that emerged as consistently important predictors of infection status. These findings suggest that volatile biomarkers may have significant potential for the development of a robust, noninvasive screening method for detecting malaria infections under field conditions. | https://doi.org/10.1073/pnas.1801512115 | Lower high school; Middle school; Upper high school |
Health-And-Medicine Articles | Can you get vaccinated without a needle | Vaccines are an important tool to help prevent the spread of infectious diseases like COVID-19. Despite their importance, it can be difficult to get such important medicine to everybody who needs it. We developed a painless vaccine patch that can make vaccines easier to transport. It could also increase access for everyone, especially those who are scared of needles! In this study, we wanted to determine if our vaccine patch could produce an immune response, increasing our bodies protection. We measured the amount of antibodies produced by the immune systems in mice who received the vaccine patch and showed that this vaccine tool is just as effective as traditional needle vaccinations. We also found that the vaccine patch protected the mice from COVID-19 after a single application. These discoveries proved that the vaccine patch can be a safe and effective form of delivering vaccinations. | Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected more than 160 million people and resulted in more than 3.3 million deaths, and despite the availability of multiple vaccines, the world still faces many challenges with their rollout. Here, we use the high-density microarray patch (HD-MAP) to deliver a SARS-CoV-2 spike subunit vaccine directly to the skin. We show that the vaccine is thermostable on the patches, with patch delivery enhancing both cellular and antibody immune responses. Elicited antibodies potently neutralize clinically relevant isolates including the Alpha and Beta variants. Last, a single dose of HD-MAPdelivered spike provided complete protection from a lethal virus challenge in an ACE2-transgenic mouse model. Collectively, these data show that HD-MAP delivery of a SARS-CoV-2 vaccine was superior to traditional needle-and-syringe vaccination and may be a significant addition to the ongoing COVID-19 (coronavirus disease 2019) pandemic. | https://www.science.org/doi/10.1126/sciadv.abj8065 | Lower high school; Upper high school |
Health-And-Medicine Articles; Social-Science Articles | Could higher junk food taxes reduce obesity | Do you like eating junk food? While it might taste great, its highly processed food which can lead to obesity. Obesity is a problem not only in richer countries, where people have higher incomes but also in poorer countries, where at the same time many people are underweight. We wanted to see if a tax on highly processed foods could have an effect on obesity rates. To evaluate that we used import tariffs as a measurement tool and created a statistical model. We found out that increasing the price difference between healthier foods and highly processed foods could be a useful step toward reducing obesity in some countries, but could also worsen the issue with underweight, sometimes even within the same country. | The consumption of highly processed food has been singled out as one of the factors responsible for the rapidly increasing prevalence of obesity and its associated non-communicable diseases and costs. While obesity prevalence is still comparatively low in lower-income sub-Saharan Africa (SSA), development prospects in this region render markets especially attractive for these foods, whose consumption is already growing at higher rates than in developed countries. This might be reflected in the massive rise in obesity prevalence growth rates in SSA over the past decade, while many of these countries are simultaneously struggling with high undernutrition prevalence. Using a newly constructed cross-country panel dataset, this study econometrically investigates the effect of higher import tariffs on highly processed vis-?-vis less-processed foods with respect to their impacts on obesity and underweight prevalence in the adult population. While the analysis is global, the discussion focuses primarily on SSA. The effects of the tariff differences are found to be significant and substantial and to differ by income level of the country as well as by gender. More generally, the results show that policies affecting the consumer price differential between the two food groups are effective in influencing obesity and underweight prevalence and that these two issues cannot be treated separately. | https://www.sciencedirect.com/science/article/pii/S0305750X19300506 | Lower high school; Upper high school |
Health-And-Medicine Articles | How accurately can molecular tests diagnose TB in China | Tuberculosis (TB) is a global health concern, especially in China where about 1 million people are diagnosed with TB each year. Early treatment is key to combating the spread of the disease, so the faster it is diagnosed, the better. Many of the traditional tests for TB take a long time to yield results. A new method, called molecular diagnosis, produces results more quickly, but is it as accurate as traditional methods in diagnosing TB? To find out, we conducted a literature review and a meta-analysis of relevant Chinese studies looking at the accuracy of six molecular diagnostic TB tests that the Chinese Food and Drug Administration has approved. We found that molecular diagnostic TB tests are simple, fast, and accurate. | This systematic review assesses the accuracy of molecular diagnostic methods for the detection of pulmonary tuberculosis in studies performed in China, published in Chinese and English. We searched for studies that assessed the accuracy of molecular diagnostics for pulmonary TB in China in the China National Knowledge Infrastructure, the Wanfang Database, SinoMed, VIP Information, Pubmed, Embase, and the Cochrane Library. For each index test, a summary estimation for sensitivity and specifcity was calculated using the bivariate random-efects model. A total of 59 studies were included in our analysis. Loop-mediated isothermal amplifcation (LAMP) assay (six studies; pooled sensitivity 90%, 95% CI 7895%; specifcity 93%, 8597%), line probe assay (LPA) (one study; 87%, 8490%; 94%, 9295%) and polymerase chain reaction (PCR) (FQ-PCR and RT-PCR) (four studies; 90%, 5599%; 93%, 7199%) showed good diagnostic performance in the meta-analysis. The highest pooled sensitivity was from Xpert MTB/RIF (20 studies; pooled sensitivity 91%, 95% CI 8794%). The highest pooled specifcity was from cross-priming amplifcation (CPA) (six studies; pooled specifcity 97%, 9599%). The lowest pooled sensitivity and specifcity were from simultaneous amplifcation and testing (SAT)-TB (three studies; 79%, 6688%; 72%, 4888%). In subgroup analysis, molecular diagnostics demonstrated higher sensitivity for pulmonary TB detection in smear-positive specimens. Xpert MTB/RIF, LAMP, LPA, CPA and PCR demonstrated high accuracy overall for pulmonary tuberculosis detection, while SAT-TB had poor performance. | https://www.nature.com/articles/s41598-019-41074-8 | Lower high school; Middle school; Upper high school |
Health-And-Medicine Articles; Social-Science Articles | How can a community protect everyone from disease | Did you know that you protect yourself and those around you by getting vaccinated? Diseases cant spread easily when enough people in a population get vaccinated. This effect is called herd immunity. Cholera is a big threat in countries that dont have safe water and toilets for everyone. These countries sometimes vaccinate large numbers of people (mass vaccination). This creates herd immunity and prevents disease outbreaks. But it is hard to know how long herd immunity will last. In one camp in South Sudan, people who had fled their homes during a war received mass vaccination. However, there was a cholera outbreak the following year. We developed a mathematical model to find out what affects how long herd immunity lasts. We found that (a) it lasts for a shorter time when a lot of people move into and out of an area, and (b) the vaccine gets less effective for each person over time. Our results suggest that herd immunity lasts longer if authorities do two things: 1. vaccinate everyone and 2. always give vaccines to new arrivals to the camp and to those who were vaccinated a long time ago. | Background Oral cholera vaccination is an approach to preventing outbreaks in at-risk settings and controlling cholera in endemic settings. However, vaccine-derived herd immunity may be short-lived due to interactions between human mobility and imperfect or waning vaccine efficacy. As the supply and utilization of oral cholera vaccines grows, critical questions related to herd immunity are emerging, including: who should be targeted; when should revaccination be performed; and why have cholera outbreaks occurred in recently vaccinated populations? Methods and findings We use mathematical models to simulate routine and mass oral cholera vaccination in populations with varying degrees of migration, transmission intensity, and vaccine coverage. We show that migration and waning vaccine efficacy strongly influence the duration of herd immunity while birth and death rates have relatively minimal impacts. As compared to either periodic mass vaccination or routine vaccination alone, a community could be protected longer by a blended Mass and Maintain strategy. We show that vaccination may be best targeted at populations with intermediate degrees of mobility as compared to communities with very high or very low population turnover. Using a case study of an internally displaced person camp in South Sudan which underwent high-coverage mass vaccination in 2014 and 2015, we show that waning vaccine direct effects and high population turnover rendered the camp over 80% susceptible at the time of the cholera outbreak beginning in October 2016. Conclusions Oral cholera vaccines can be powerful tools for quickly protecting a population for a period of time that depends critically on vaccine coverage, vaccine efficacy over time, and the rate of population turnover through human mobility. Due to waning herd immunity, epidemics in vaccinated communities are possible but become less likely through complementary interventions or data-driven revaccination strategies. | https://doi.org/10.1371/journal.pntd.0006257 | Lower high school; Middle school |
Health-And-Medicine Articles | How can a tiny particle reduce peanut allergies | Did you know that food can be harmful to certain people? protein. It would also tell the body to make protective cells Thats because they have food allergies. Food allergies can to decrease the allergic reaction. be dangerous if they cause anaphylaxis. This is the bodys The researchers designed a very tiny particle to take mRNA reaction to the food. It can be so bad that it may become to the liver. They designed the mRNA to switch off allergic difficult to breathe. It can also cause a person to faint. responses. They then collected data to determine if there Scientists wanted to figure out if they could use a special were fewer symptoms of anaphylaxis. The tests showed that particle called messenger RNA (mRNA) to help. They hoped particles carrying mRNA could reduce the impact of peanut it could reduce the symptoms of anaphylaxis caused by allergies. That means that mRNA could be an effective this food. This mRNA would tell the body to make peanut solution to allergies in the future. | While oral desensitization is capable of alleviating peanut allergen anaphylaxis, long-term immune tolerance is the sought-after goal. We developed a liver-targeting lipid nanoparticle (LNP) platform to deliver mRNA-encoded peanut allergen epitopes to liver sinusoidal endothelial cells (LSECs), which function as robust tolerogenic antigen-presenting cells that induce FoxP3+ regulatory T-cells (Tregs). The mRNA strand was constructed by including nucleotide sequences encoding for nonallergenic MHC-II binding T-cell epitopes, identified in the dominant peanut allergen, Ara h2. These epitopes were inserted in the mRNA strand downstream of an MHC-II targeting sequence, further endowed in vitro with 5' and 3' capping sequences, a PolyA tail, and uridine substitution. Codon-optimized mRNA was used for microfluidics synthesis of LNPs with an ionizable cationic lipid, also decorated with a lipid-anchored mannose ligand for LSEC targeting. Biodistribution to the liver was confirmed by in vivo imaging, while ELISpot assays demonstrated an increase in IL-10-producing Tregs in the spleen. Prophylactic administration of tandem-repeat or a combination of encapsulated Ara h2 epitopes induced robust tolerogenic effects in C3H/HeJ mice, sensitized to and subsequently challenged with crude peanut allergen extract. In addition to alleviating physical manifestations of anaphylaxis, there was suppression of Th2-mediated cytokine production, IgE synthesis, and mast cell release, accompanied by increased IL-10 and TGF- production in the peritoneum. Similar efficacy was demonstrated during LNP administration postsensitization. While nondecorated particles had lesser but significant effects, PolyA/LNP-Man lacked protective effects. These results demonstrate an exciting application of mRNA/LNP for treatment of food allergen anaphylaxis, with the promise to be widely applicable to the allergy field. | https://pubs.acs.org/doi/10.1021/acsnano.2c12420 | Lower high school |
Health-And-Medicine Articles | How can being sick with COVID-19 in the past protect you in the future | Did you have COVID-19? Maybe you are better protected than you think! COVID-19 has changed a lot during the past three years. This makes it harder to fight. To try to stop the virus from spreading, scientists created vaccines. And many people got vaccinated! But some people who had COVID-19 might not need a vaccine because they are already protected. We wanted to know if this is true. We looked at 65 studies and found out that a past infection offers good protection. This is especially true for older variants of the virus. The protection against the newest variant, Omicron, is weaker. It also declines faster with time. But the good news is that a past infection will still protect you from getting really sick! | Summary Background Understanding the level and characteristics of protection from past SARS-CoV-2 infection against subsequent re-infection, symptomatic COVID-19 disease, and severe disease is essential for predicting future potential disease burden, for designing policies that restrict travel or access to venues where there is a high risk of transmission, and for informing choices about when to receive vaccine doses. We aimed to systematically synthesise studies to estimate protection from past infection by variant, and where data allow, by time since infection. Methods In this systematic review and meta-analysis, we identified, reviewed, and extracted from the scientific literature retrospective and prospective cohort studies and test-negative case-control studies published from inception up to Sept 31, 2022, that estimated the reduction in risk of COVID-19 among individuals with a past SARS-CoV-2 infection in comparison to those without a previous infection. We meta-analysed the effectiveness of past infection by outcome (infection, symptomatic disease, and severe disease), variant, and time since infection. We ran a Bayesian meta-regression to estimate the pooled estimates of protection. Risk-of-bias assessment was evaluated using the National Institutes of Health quality-assessment tools. The systematic review was PRISMA compliant and was registered with PROSPERO (number CRD42022303850). Findings We identified a total of 65 studies from 19 different countries. Our meta-analyses showed that protection from past infection and any symptomatic disease was high for ancestral, alpha, beta, and delta variants, but was substantially lower for the omicron BA.1 variant. Pooled effectiveness against re-infection by the omicron BA.1 variant was 453% (95% uncertainty interval [UI] 173761) and 440% (265650) against omicron BA.1 symptomatic disease. Mean pooled effectiveness was greater than 78% against severe disease (hospitalisation and death) for all variants, including omicron BA.1. Protection from re-infection from ancestral, alpha, and delta variants declined over time but remained at 786% (498936) at 40 weeks. Protection against re-infection by the omicron BA.1 variant declined more rapidly and was estimated at 361% (244513) at 40 weeks. On the other hand, protection against severe disease remained high for all variants, with 902% (697975) for ancestral, alpha, and delta variants, and 889% (847909) for omicron BA.1 at 40 weeks. Interpretation Protection from past infection against re-infection from pre-omicron variants was very high and remained high even after 40 weeks. Protection was substantially lower for the omicron BA.1 variant and declined more rapidly over time than protection against previous variants. Protection from severe disease was high for all variants. The immunity conferred by past infection should be weighed alongside protection from vaccination when assessing future disease burden from COVID-19, providing guidance on when individuals should be vaccinated, and designing policies that mandate vaccination for workers or restrict access, on the basis of immune status, to settings where the risk of transmission is high, such as travel and high-occupancy indoor settings. | https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(22)02465-5/fulltext | Lower high school; Middle school |
Health-And-Medicine Articles | How can synthetic proteins help premature babies | Sometimes babies are born premature three weeks its expensive and sometimes dangerous. This is why we or more before they are due. Premature babies often wanted to test a new possible way: letting the baby inhale have health problems. One of the most common issues synthetic lung surfactant. We developed dry powders is breathing problems, because the lungs havent fully containing synthetic surfactant and tried them both in the developed yet. The immature lungs lack a specific mixture lab and on animal models rabbits and lambs lacking lung of lipids and proteins, called surfactant, which allows the surfactant. Our results show that the delivery of a surfactant lungs to expand. The current treatment for this condition powder through the windpipe gives better results, but that is the introduction of animal surfactant through a tube in two inhalation doses of the synthetic surfactant are a safe the babys windpipe. This method is often successful, but and effective method to improve lung function. | Background: The development of synthetic lung surfactant for preterm infants has focused on peptide analogues of native surfactant proteins B and C (SP-B and SP-C). Non-invasive respiratory support with nasal continuous positive airway pressure (nCPAP) may benefit from synthetic surfactant for aerosol delivery. Methods: A total of three dry powder (DP) surfactants, consisting of phospholipids and the SP-B analogue Super Mini-B (SMB), and one negative control DP surfactant without SMB, were produced with the Acorda Therapeutics ARCUS Pulmonary Dry Powder Technology. Structure of the DP surfactants was compared with FTIR spectroscopy, in vitro surface activity with captive bubble surfactometry, and in vivo activity in surfactant-deficient adult rabbits and preterm lambs. In the animal experiments, intratracheal (IT) aerosol delivery was compared with surfactant aerosolization during nCPAP support. Surfactant dosage was 100 mg/kg of lipids and aerosolization was performed using a low flow inhaler. Results: FTIR spectra of the three DP surfactants each showed secondary structures compatible with peptide folding as an -helix hairpin, similar to that previously noted for surface-active SMB in other lipids. The DP surfactants with SMB demonstrated in vitro surface activity <1 mN/m. Oxygenation and lung function increased quickly after IT aerosolization of DP surfactant in both surfactant-deficient rabbits and preterm lambs, similar to improvements seen with clinical surfactant. The response to nCPAP aerosol delivery of DP surfactant was about 50% of IT aerosol delivery, but could be boosted with a second dose in the preterm lambs. Conclusions: Aerosol delivery of DP synthetic surfactant during non-invasive respiratory support with nCPAP significantly improved oxygenation and lung function in surfactant-deficient animals and this response could be enhanced by giving a second dose. Aerosol delivery of DP synthetic lung surfactant has potential for clinical applications. | https://gatesopenresearch.org/articles/3-6/v2 | Lower high school; Middle school; Upper high school |
Health-And-Medicine Articles; Social-Science Articles | How can we better prevent polio | Polio is a potentially deadly and yet preventable disease. A vaccine is available but in order to get rid of the disease, this vaccine needs to have larger coverage. Unfortunately, this is not an easy goal in poorer countries. A single shot of polio vaccine is not enough to prevent the disease, and in developing countries, healthcare workers have difficulties reaching their patients more than once. This is why we wanted to develop a vaccine that requires only one injection. We used safe compounds to mimic the current 2-shot schedule and to stabilize the vaccine. Our tests showed promising results, and hopefully, this approach will help with the development of vaccines against other infectious diseases as well. | Vaccination in the developing world is hampered by limited patient access, which prevents individuals from receiving the multiple injections necessary for protective immunity. Here, we developed an injectable microparticle formulation of the inactivated polio vaccine (IPV) that releases multiple pulses of stable antigen over time. To accomplish this, we established an IPV stabilization strategy using cationic polymers for pH modulation to enhance traditional small-moleculebased stabilization methods. We investigated the mechanism of this strategy and showed that it was broadly applicable to all three antigens in IPV. Our lead formulations released two bursts of IPV 1 month apart, mimicking a typical vaccination schedule in the developing world. One injection of the controlled-release formulations elicited a similar or better neutralizing response in rats, considered the correlate of protection in humans, than multiple injections of liquid vaccine. This single-administration vaccine strategy has the potential to improve vaccine coverage in the developing world. | https://www.pnas.org/content/115/23/e5269 | Lower high school; Upper high school |
Health-And-Medicine Articles | How can we control HIV worldwide | HIV is a virus that weakens a persons immune system. If the Researchers are developing a vaccine that can stop people from immune system is weak, it cant defend against diseases getting infected with HIV in the first place. In this study, we making something as simple as a cold life-threatening. Did found that providing treatment to more people living with HIV you know that about half of the people living with HIV are not will save a lot of lives. However, if we also gave people a vaccine getting the treatment they need? As a result, millions of people that protects them from getting HIV, we could lead the world die from HIV worldwide every year. But what if we provided HIV towards getting rid of HIV forever. treatment to more people? What if people could get vaccinated? | The HIV pandemic continues to impose enormous morbidity, mortality, and economic burdens across the globe. Simultaneously, innovations in antiretroviral therapy, diagnostic approaches, and vaccine development are providing novel tools for treatment-as-prevention and prophylaxis. We developed a mathematical model to evaluate the added benefit of an HIV vaccine in the context of goals to increase rates of diagnosis, treatment, and viral suppression in 127 countries. Under status quo interventions, we predict a median of 49 million [first and third quartiles 44M, 58M] incident cases globally from 2015 to 2035. Achieving the Joint United Nations Program on HIV/AIDS 959595 target was estimated to avert 25 million [20M, 33M] of these new infections, and an additional 6.3 million [4.8M, 8.7M] reduction was projected with the 2020 introduction of a 50%-efficacy vaccine gradually scaled up to 70% coverage. This added benefit of prevention through vaccination motivates imminent and ongoing clinical trials of viable candidates to realize the goal of HIV control. | http://www.pnas.org/content/114/15/4017 | Lower high school |
Health-And-Medicine Articles; Social-Science Articles | How can we eliminate malaria in Haiti | Malaria kills over , people every year, making it the We learned that many people havent heard of malaria or deadliest mosquito-borne infection in the world. Haiti and dont perceive it as dangerous or as a disease at all. Most the Dominican Republic are the only two Caribbean countries participants thought that increasing the access to mosquito where malaria is present - and they are committed to nets would be the most accepted strategy, as many locals eliminating it by . dont trust pills and refuse to be tested. Our results showed us that increasing malaria awareness is very important. However, we know little about how local people perceive Its also essential to include the collaboration of traditional malaria. Would they accept the interventions the government healers as many sick people seek their help instead of going has planned to eliminate the disease? To find out, we to a health clinic for treatment. performed interviews with health workers, traditional healers, priests, teachers, public officials, and community members. | Haiti and the Dominican Republic, the only two Caribbean countries with endemic malaria transmission, are committed to eliminating malaria. With aPlasmodium falciparumprevalence under 1% and a highly focal transmission, the efforts towards elimination in Haiti will include several community-based interventions that must be tailored to the local sociocultural context to increase their uptake. However, little is known about local community perceptions regarding malaria and the planned elimination interventions. The aim of this study is to develop a robust understanding of how to tailor, implement and promote malaria elimination strategies in Haiti. | https://doi.org/10.1186/s12936-018-2553-5 | Lower high school; Middle school |
Health-And-Medicine Articles | How can we help stop the COVID-19 pandemic | The new coronavirus has already claimed the lives of impact on peoples health and the state of the healthcare hundreds of thousands of people. Different countries are systems in two countries: the UK and the US. We found that taking different measures in the fight against this new social distancing of the whole population, not just the elderly, threat. Many people are staying at home. But is it worth it? would have the most beneficial effect. The combination of Thats what we wanted to find out. this measure with others would be even better. We created a computer model that helps us assess the effect of different measures against COVID-. We checked for the | The global impact of COVID-19 has been profound, and the public health threat it represents is the most serious seen in a respiratory virus since the 1918 H1N1 influenza pandemic. Here we present the results of epidemiological modelling which has informed policymaking in the UK and other countries in recent weeks. In the absence of a COVID-19 vaccine, we assess the potential role of a number of public health measures so-called non-pharmaceutical interventions (NPIs) aimed at reducing contact rates in the population and thereby reducing transmission of the virus. In the results presented here, we apply a previously published microsimulation model to two countries: the UK (Great Britain specifically) and the US. We conclude that the effectiveness of any one intervention in isolation is likely to be limited, requiring multiple interventions to be combined to have a substantial impact on transmission. Two fundamental strategies are possible: (a) mitigation, which focuses on slowing but not necessarily stopping epidemic spread reducing peak healthcare demand while protecting those most at risk of severe disease from infection, and (b) suppression, which aims to reverse epidemic growth, reducing case numbers to low levels and maintaining that situation indefinitely. Each policy has major challenges. We find that that optimal mitigation policies (combining home isolation of suspect cases, home quarantine of those living in the same household as suspect cases, and social distancing of the elderly and others at most risk of severe disease) might reduce peak healthcare demand by 2/3 and deaths by half. However, the resulting mitigated epidemic would still likely result in hundreds of thousands of deaths and health systems (most notably intensive care units) being overwhelmed many times over. For countries able to achieve it, this leaves suppression as the preferred policy option. We show that in the UK and US context, suppression will minimally require a combination of social distancing of the entire population, home isolation of cases and household quarantine of their family members. This may need to be supplemented by school and university closures, though it should be recognised that such closures may have negative impacts on health systems due to increased absenteeism. The major challenge of suppression is that this type of intensive intervention package or something equivalently effective at reducing transmission will need to be maintained until a vaccine becomes available (potentially 18 months or more) given that we predict that transmission will quickly rebound if interventions are relaxed. We show that intermittent social distancing triggered by trends in disease surveillance may allow interventions to be relaxed temporarily in relative short time windows, but measures will need to be reintroduced if or when case numbers rebound. Last, while experience in China and now South Korea show that suppression is possible in the short term, it remains to be seen whether it is possible long-term, and whether the social and economic costs of the interventions adopted thus far can be reduced. | https://spiral.imperial.ac.uk:8443/handle/10044/1/77482 | Lower high school; Upper high school |
Health-And-Medicine Articles | How can we keep kids from dying from diarrhea | Many different bacteria, viruses, and parasites can cause diarrhea. Sometimes diarrhea is just uncomfortable, sometimes its deadly. In fact, in many countries in Africa and Asia, diarrhea is a major cause of death in children. If a childs diarrhea is caused by some types of bacteria, Shigella, for instance, things can get pretty bad. Shigella is a leading cause of morbidity (the rate of disease in a population) and mortality (the number of deaths due to a disease) among children worldwide. Some countries dont have the ability to test for Shigella, so doctors rely only on symptoms to diagnose it and to see if antibiotic treatment is needed. We wanted to check if the method recommended by the World Health Organization (WHO) looking for blood in childrens stool really identifies Shigella-infected children. We found that it doesnt only a small proportion of children with Shigella had blood in their stool. We, therefore, recommend using a different method to determine which children with diarrhea need antibiotic treatment | Background Shigella is a leading cause of childhood diarrhea mortality in sub-Saharan Africa. Current World Health Organization guidelines recommend antibiotics for children in non cholera-endemic areas only in the presence of dysentery, a proxy for suspected Shigella infection. Methods To assess the sensitivity and specificity of the syndromic diagnosis of Shigella-associated diarrhea, we enrolled children aged 6 months to 5 years presenting to 1 of 3 Western Kenya hospitals between November 2011 and July 2014 with acute diarrhea. Stool samples were tested using standard methods for bacterial culture and multiplex polymerase chain reaction for pathogenic Escherichia coli. Stepwise multivariable logit models identified factors to increase the sensitivity of syndromic diagnosis. Results Among 1360 enrolled children, median age was 21 months (interquartile range, 1137), 3.4% were infected with human immunodeficiency virus, and 16.5% were stunted (height-for-age z-score less than ?2). Shigella was identified in 63 children (4.6%), with the most common species being Shigella sonnei (53.8%) and Shigella flexneri (40.4%). Dysentery correctly classified 7 of 63 Shigella cases (sensitivity, 11.1%). Seventy-eight of 1297 children without Shigella had dysentery (specificity, 94.0%). The combination of fecal mucous, age over 23 months, and absence of excessive vomiting identified more children with Shigella-infection (sensitivity, 39.7%) but also indicated antibiotics in more children without microbiologically confirmed Shigella (specificity, 82.7%). Conclusions Reliance on dysentery as a proxy for Shigella results in the majority of Shigella-infected children not being identified for antibiotics. Field-ready rapid diagnostics or updated evidence-based algorithms are urgently needed to identify children with diarrhea most likely to benefit from antibiotic therapy. | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5181358/ | Lower high school; Upper high school |
Health-And-Medicine Articles | How can we keep the world free of measles | Have you had chickenpox? Do you remember how ill it made countries have good health care. In these countries measles you feel? Add a fever and aching bones, and youre close to how still kills tens of thousands of children every year. Vaccination youd feel if you had measles (Figure )... programs have reduced the number of cases, but its very hard Chickenpox and measles are caused by viruses, and both are to completely eliminate it and stop it from coming back. very contagious. This means they can spread very easily from In this study, we created mathematical models to study how one person to another. Measles can make you very sick, and well different vaccination programs could work at preventing people can even die from it. the disease from spreading through a country. We learned that Luckily for us, measles is now very uncommon in countries under the right conditions, it can be possible to keep measles with strong health care, because most people get vaccinated away for good. by doctors or nurses when they are young. However, not all Figure : The measles virus causes an infection | All six WHO regions currently have goals for measles elimination by 2020. Measles vaccination is delivered via routine immunization programmes, which in most sub-Saharan African countries reach children around 9 months of age, and supplementary immunization activities (SIAs), which target a wider age range at multi-annual intervals. In the absence of endemic measles circulation, the proportion of individuals susceptible to measles will gradually increase through accumulation of new unvaccinated individuals in each birth cohort, increasing the risk of an epidemic. The impact of SIAs and the financial investment they require, depend on coverage and target age range.We evaluated the impact of target population age range for periodic SIAs, evaluating outcomes for two different levels of coverage, using a demographic and epidemiological model adapted to reflect populations in 4 sub-Saharan African countries.We found that a single SIA can maintain elimination over short time-scales, even with low routine coverage. However, maintaining elimination for more than a few years is difficult, even with large (high coverage/wide age range) recurrent SIAs, due to the build-up of susceptible individuals. Across the demographic and vaccination contexts investigated, expanding SIAs to target individuals over 10 years did not significantly reduce outbreak risk. Conclusions Elimination was not maintained in the contexts we evaluated without a second opportunity for vaccination. In the absence of an expanded routine program, SIAs provide a powerful option for providing this second dose. We show that a single high coverage SIA can deliver most key benefits in terms of maintaining elimination, with follow-up campaigns potentially requiring smaller investments. This makes post-campaign evaluation of coverage increasingly relevant to correctly assess future outbreak risk. | https://www.sciencedirect.com/science/article/pii/S0264410X1730172X | Lower high school; Middle school |