Environment Awareness Report
2023 Environ Base [19]
May 2023
39 News Items
| wdt_ID | NIH REF | KEY | HEADLINE | SUMMARY | SOURCE | JOURNAL | CONTENT | ITEM # |
|---|---|---|---|---|---|---|---|---|
| 118 | 2319-E028 | E01 E04 | Pollen Production's Impact on Cloud Formation | The onset of springtime brings a myriad of problems for millions of people suffering from seasonal allergies. Recent research has shown that the increase in allergy season severity can be attributed to climate change. The study also revealed that common allergy-triggering plants release more sub-pollen particles than previously thought, which can have an impact on cloud formations. | American Chemical Society | ACS Earth and Space Chemistry | For millions of people with seasonal allergies, springtime means runny noses, excessive sneezes and itchy eyes. And, as with many things, climate change appears to be making allergy season even worse. Researchers reporting in ACS Earth and Space Chemistry have shown that common allergen-producing plants ryegrass and ragweed emit more smaller, "subpollen particles" (SPPs) than once thought, yet climate would likely be most affected by their intact pollen grains, which can boost cloud formation. -- In addition to annoying sinuses, pollen naturally functions as a way for plants to exchange genetic material and reproduce. When exposed to moisture, these pollen grains can burst into tiny SPPs less than a micron long. Their smaller size allows them to reach the lower respiratory system, where they can last longer and cause more inflammation than their larger counterparts. Both SPPs and whole pollen grains are also thought to act as ice nucleation sites -- miniature starting points for clouds. But compared to regular clouds, SPPs and pollen form smaller, more numerous clouds that tend to hold onto their precipitation, helping trap in radiant heat and contributing to climate change. In turn, higher temperatures can extend pollen-release periods, further exacerbating the problem. Previously, Brianna Matthews, Alyssa Alsante and Sarah Brooks studied how oak trees emit SPPs at different humidity levels. But this time, the team wanted to investigate how two other common allergen-producing plants, ragweed and ryegrass, release SPPs under humid conditions, and how those particles could affect ice cloud formation. -- The researchers collected samples of ryegrass and ragweed, then placed them into a specialized "pollen chamber." There, the samples were exposed to different humidity levels and bursts of wind over several hours to simulate real-world conditions. -- The group assessed the number of SPPs per pollen grain, as well as the abilities of both to nucleate ice. Surprisingly, the team found that previous experiments on the same types of plants underestimated the amount of SPPs by a factor of 10 to 100. This was likely because the other experiments used a less realistic means of spreading the pollen and generating the SPPs, say the researchers. Ragweed and ryegrass SPPs were very poor ice-nucleating sites, however -- barely better than plain water -- while whole pollen grains facilitated cloud growth. The researchers say that these updated parameters and numbers of emitted pollen grains and particles could ultimately be used to create more-accurate climate models. [] Hypoallergenic, Allergen, Paleoclimatology, Global climate model, Global warming controversy, Kyoto Protocol, Consensus of scientists regarding global warming, Temperature record of the past 1000 years | 2319-E028 |
| 119 | 2319-E041 | E01 E03 | Plastic's Drift in the Sea | Plastic debris that accumulates on the surface of oceans can drift farther underwater than previously thought, according to recent research. Computer modeling was used to study the movement of lightweight plastic particles in the Mediterranean Sea, revealing that these particles can travel significant distances underwater. | American Chemical Society | Environmental Science & Technology | Discarded or drifting in the ocean, plastic debris can accumulate on the water's surface, forming floating islands of garbage. Although it's harder to spot, researchers suspect a significant amount also sinks. In a new study in ACS' Environmental Science & Technology, one team used computer modeling to study how far bits of lightweight plastic travel when falling into the Mediterranean Sea. Their results suggest these particles can drift farther underwater than previously thought. -- From old shopping bags to water bottles, plastic pollution is besieging the oceans. Not only is this debris unsightly, animals can become trapped in it or mistakenly eat it. And if it remains in the water, plastic waste can release organic pollutants. The problem is most visible on the surface, where currents can aggregate this debris into massive, so-called garbage patches. However, plastic waste also collects much deeper. Even material that weighs less than water can sink as algae and other organisms glom onto it, and through other processes. Bits of this light plastic, which typically measure 5 millimeters or less, have turned up at least half a mile below the surface. Researchers don't know much about what happens when plastic sinks, but they generally assume it falls straight down from the surface. However, Alberto Baudena and his colleagues suspected this light plastic might not follow such a direct route. -- To test this assumption, they used an advanced computer model developed to track plastic at sea and incorporated extensive data already collected on floating plastic pollution in the Mediterranean Sea. They then simulated nearly 7.7 million bits of plastic distributed across the sea and tracked their virtual paths to depths as great as about half a mile. Their results suggested that the slower the pieces sank, the farther currents carried them from their points of origin, with slowest traveling an average of roughly 175 miles laterally. While observations of the distribution of plastic underwater are limited, the team found their simulations agree with those available in the Mediterranean. Their simulations also suggested that currents may push plastic toward coastal areas and that only about 20% of pollution near coasts originates from the nearest country. These particles' long journeys mean this plastic has greater potential to interact with, and harm, marine life, according to the researchers. [] Ocean surface wave, Ice shelf, Computer simulation, Ocean, Underwater explosion, Mid-ocean ridge, Atmospheric chemistry | 2319-E041 |
| 120 | 2319-E024 | E05 | Tuberculosis Disease and HIV Antibody Response | People living with HIV that have had pulmonary tuberculosis have been found to have broader and more potent HIV antibody responses, as compared to those without suspected or documented tuberculosis. | Boston Medical Center | iScience | New research from Boston Medical Center found that people living with HIV that have had pulmonary tuberculosis had broader and more potent HIV antibody responses and differences in HIV sequences predicted to be antibody resistant as compared to those without suspected or documented tuberculosis. Published in iScience, the study suggests that concomitant tuberculosis disease has a significant impact on HIV immune responses and the viruses circulating in people living with HIV. -- Tuberculosis infects more than 2 billion people in the world, and although tuberculosis is the most common co-infection in people living with HIV, previous studies have not examined how tuberculosis impacts HIV immune responses and virus characteristics. -- This study suggest that tuberculosis may impact the efficacy of antibody based prevention and therapeutic strategies. Vaccines to elicit antibodies and antibodies are also being investigated as a means to treat and cure HIV. Higher prevalence of antibody resistant strains along with tuberculosis disease implies that these antibody-based interventions are more likely to in fail in these individuals. -- "Tuberculosis is extremely common, especially in regions of the world with high levels of ongoing HIV transmission, and impacts both the immune responses and the characteristics of the circulating virus in people living with HIV so it is imperative we understand the relationship between the two," said Manish Sagar, MD, an internist at Boston Medical Center and Professor of Medicine at Boston University Chobanian & Avedisian School of Medicine. "These studies have implications for HIV vaccines and antibody based HIV therapeutics." -- Researchers worked closely with investigators in Uganda and at the AIDS Clinical Trial Group (ACTG) to collect samples from people newly diagnosed with HIV that either did or did not have tuberculosis. From these individuals, they examined samples collected prior to and about 6 months after the start of HIV medications. Researchers compared antibodies, plasma inflammatory markers, and HIV sequences in the baseline and in treatment samples. -- Tuberculosis disease is associated with higher prevalence of the some antibody resistant HIV. High ongoing HIV transmission in areas of the world with frequent tuberculosis disease suggest that a potential vaccine that elicits broad and potent antibodies may not work because these geographic regions are more likely to have antibody resistant strains. -- Researchers highlight that this study has implications for HIV vaccine strategies as they aim to generate antibodies that can block the virus after exposure. Generating broad and potent HIV antibodies has not been accomplished and remains a monumental challenge. But Tuberculosis disease generates broadly potent antibody responses and dissecting biological pathways that provide insight into how tuberculosis enhances HIV antibody responses could be leveraged to develop novel strategies for eliciting broad and potent HIV antibodies. [] Tuberculosis, HIV test, Antiretroviral drug, AIDS, HIV, Vaccination, Lymphoma, Monoclonal antibody therapy | 2319-E024 |
| 121 | 2319-E025 | E01 E02 | Ice Age Human Migrations to Americas and Japan | Scientists have traced a female lineage from northern coastal China to the Americas by using mitochondrial DNA. Their findings suggest evidence of at least two migrations: one during the last ice age and one during the subsequent melting period. | Cell Press | Cell Reports | Scientists have used mitochondrial DNA to trace a female lineage from northern coastal China to the Americas. By integrating contemporary and ancient mitochondrial DNA, the team found evidence of at least two migrations: one during the last ice age, and one during the subsequent melting period. Around the same time as the second migration, another branch of the same lineage migrated to Japan, which could explain Paleolithic archeological similarities between the Americas, China, and Japan. The study appears May 9 in the journal Cell Reports. -- "The Asian ancestry of Native Americans is more complicated than previously indicated," says first author Yu-Chun Li, a molecular anthropologist at the Chinese Academy of Sciences. "In addition to previously described ancestral sources in Siberia, Australo-Melanesia, and Southeast Asia, we show that northern coastal China also contributed to the gene pool of Native Americans." -- Though it was long assumed that Native Americans descended from Siberians who crossed over the Bering Strait's ephemeral land bridge, more recent genetic, geological, and archeological evidence suggests that multiple waves of humans journeyed to the Americas from various parts of Eurasia. -- To shed light on the history of Native Americans in Asia, a team of researchers from the Chinese Academy of Sciences followed the trail of an ancestral lineage that might link East Asian Paleolithic-age populations to founding populations in Chile, Peru, Bolivia, Brazil, Ecuador, Mexico, and California. The lineage in question is present in mitochondrial DNA, which can be used to trace kinship through the female line. -- The researchers scoured over 100,000 contemporary and 15,000 ancient DNA samples from across Eurasia to eventually identify 216 contemporary and 39 ancient individuals belonging to the rare lineage. By comparing the accumulated mutations, geographic locations, and carbon-dated age of each of these individuals, the researchers were able to trace the lineage's branching path. They identified two migration events from northern coastal China to the Americas, and in both cases, they think that the travelers probably set dock in America via the Pacific coast rather than by crossing the inland ice-free corridor (which would not have opened at the time). -- The first radiation event occurred between 19,500 and 26,000 years ago during the Last Glacial Maximum, when ice sheet coverage was at its greatest and conditions in northern China were likely inhospitable for humans. The second radiation occurred during the subsequent deglaciation or melting period, between 19,000 and 11,500 years ago. There was a rapid increase in human populations at this time, probably due to the improved climate, which may have fueled expansion into other geographical regions. -- The researchers also uncovered an unexpected genetic link between Native Americans and Japanese people. During the deglaciation period, another group branched out from northern coastal China and traveled to Japan. "We were surprised to find that this ancestral source also contributed to the Japanese gene pool, especially the indigenous Ainus," says Li. -- This discovery helps to explain archeological similarities between the Paleolithic peoples of China, Japan, and the Americas. Specifically, the three regions share similarities in how they crafted stemmed projectile points for arrowheads and spears. "This suggests that the Pleistocene connection among the Americas, China, and Japan was not confined to culture but also to genetics," says senior author Qing-Peng Kong, an evolutionary geneticist at the Chinese Academy of Sciences. -- Though the study focused on mitochondrial DNA, complementary evidence from Y chromosomal DNA suggests that male ancestors of Native Americans also lived in northern China at around the same time as these female ancestors. -- This study adds another piece to the puzzle that is Native American ancestry, but many other elements remain unclear. "The origins of several founder groups are still elusive or controversial," says Kong. "Next, we plan to collect and investigate more Eurasian lineages to obtain a more complete picture on the origin of Native Americans." [] Human migration, Indigenous peoples of the Americas, Chichen Itza, RNA, Maya civilization, Little Ice Age, Geologic temperature record, The Genographic Project | 2319-E025 |
| 122 | 2319-E034 | E01 E02 | Additive Improves Efficiency of Solar Cells | Researchers have made significant progress in the development of perovskite solar cells (PVSCs) by developing an innovative multifunctional and non-volatile additive. This breakthrough could pave the way for the commercialization of PVSCs, which are a promising alternative to traditional silicon-based solar cells. | City University of Hong Kong | Nature Photonics | Perovskite solar cells (PVSCs) are a promising alternative to traditional silicon-based solar cells because of their high power-conversion efficiency and low cost. However, one of the major challenges in their development has been achieving long-term stability. Recently, a research team from City University of Hong Kong (CityU) made a breakthrough by developing an innovative multifunctional and non-volatile additive which can improve the efficiency and stability of perovskite solar cells by modulating perovskite film growth. This simple and effective strategy has great potential for facilitating the commercialisation of PVSCs. -- "This type of multifunctional additive can be generally used to make different perovskite compositions for fabricating highly efficient and stable perovskite solar cells. The high-quality perovskite films will enable the upscaling of large-area solar panels," explained Professor Alex Jen Kwan-yue, Lee Shau Kee Chair Professor of Materials Science and Director of the Hong Kong Institute for Clean Energy at CityU, who led the study. -- PVSCs have attracted significant attention due to their impressive solar power conversion efficiency (PCE). Since perovskites can be deposited from solutions onto the fabrication surfaces, PVSCs have the potential to be applied in building-integrated photovoltaics (BIPV), wearable devices, and solar farm applications. However, the efficiency and stability are still affected by the severe energy loss associated with defects embedded at the interfaces and grain boundaries of the perovskites. Therefore, the intrinsic quality of perovskite film plays a critical role in determining the achievable efficiency and stability of PVSCs. -- Although many previous research studies have focused on improving the film morphology and quality with volatile additives, these additives tend to escape from the film after annealing, creating a void at the perovskite-substrate interface. -- To tackle these issues, the CityU researchers developed a simple but effective strategy of modulating the perovskite film growth to enhance the film quality. They found that by adding a multifunctional molecule (4-guanidinobenzoic acid hydrochloride, (GBAC)) to the perovskite precursor, a hydrogen-bond-bridged intermediate phase is formed and modulates the crystallization to achieve high-quality perovskite films with large perovskite crystal grains and coherent grain growth from the bottom to the surface of the film. This molecule can also serve as an effective defect passivation linker (a method to reduce the defect density of perovskite film) in the annealed perovskite film due to its non-volatility, resulting in significantly reduced non-radiative recombination loss and improved film quality. -- Their experiments showed that the defect density of perovskite films can be significantly reduced after introducing GBAC. The power conversion efficiency of inverted (p-i-n) perovskite solar cells based on the modified perovskites was boosted to 24.8% (24.5% certified by the Japan Electrical Safety & Environment Technology Laboratories), which is among the highest values reported in the literature. Also, the overall energy loss of the device was reduced to 0.36eV, representing one of the lowest energy losses among the PVSC devices with high power conversion efficiency. -- Additionally, the unencapsulated devices exhibit improved thermal stability beyond 1,000 hours under continuous heating at 65 ± 5°C in a nitrogen-filled glovebox while maintaining 98% of the original efficiency. -- The team demonstrated the general applicability of this strategy for different perovskite compositions and large-area devices. For example, a larger area device (1 cm2) in the experiment delivered a high PCE of 22.7% with this strategy, indicating excellent potential for fabricating scalable, highly efficient PVSCs. -- "This work provides a clear path to achieving optimised perovskite film quality to facilitate the development of highly efficient and stable perovskite solar cells and their upscaling for practical applications," said Professor Jen. -- In the future, the team aims to further extend the molecular structures and optimize the device structure through compositional and interfacial engineering. They will also focus on the fabrication of large-area devices. [] Solar cell, Alternative fuel vehicle, Solar power, Renewable energy, Solar panel, Energy development, Hadley cell, History of Earth | 2319-E034 |
| 123 | 2319-E004 | E01 E02 | Microbes' Benefits for Green Biomanufacturing | Scientists have discovered a new route in bacteria to decarbonize industry, potentially reducing greenhouse gas emissions from the manufacturing of fuels, drugs, and chemicals. They engineered bacteria to produce new-to-nature carbon products that could provide a powerful route to sustainable biochemicals. | DOE/Lawrence Berkeley National Laboratory | Nature | A research team led by Lawrence Berkeley National Laboratory (Berkeley Lab) and UC Berkeley has engineered bacteria to produce new-to-nature carbon products that could provide a powerful route to sustainable biochemicals. -- The advance -- which was recently announced in the journal Nature -- uses bacteria to combine natural enzymatic reactions with a new-to-nature reaction called the "carbene transfer reaction." This work could also one day help reduce industrial emissions because it offers sustainable alternatives to chemical manufacturing processes that typically rely on fossil fuels. -- "What we showed in this paper is that we can synthesize everything in this reaction -- from natural enzymes to carbenes -- inside the bacterial cell. All you need to add is sugar and the cells do the rest," said Jay Keasling, a principal investigator of the study and CEO of the Department of Energy's Joint BioEnergy Institute (JBEI). -- Carbenes are highly reactive carbon-based chemicals that can be used in many different types of reactions. For decades, scientists have wanted to use carbene reactions in the manufacturing of fuels and chemicals, and in drug discovery and synthesis. -- But these carbene processes could only be carried out in small batches via test tubes and required expensive chemical substances to drive the reaction. -- In the new study, the researchers replaced expensive chemical reactants with natural products that can be produced by an engineered strain of the bacteria Streptomyces. Because the bacteria use sugar to produce chemical products through cellular metabolism, "this work enables us to perform the carbene chemistry without toxic solvents or toxic gases typically used in chemical synthesis," said first author Jing Huang, a Berkeley Lab postdoctoral researcher in the Keasling Lab. "This biological process is much more environmentally friendly than the way chemicals are synthesized today," Huang said. -- During experiments at JBEI, the researchers observed the engineered bacterium as it metabolized and converted sugars into the carbene precursor and the alkene substrate. The bacterium also expressed an evolved P450 enzyme that used those chemicals to produce cyclopropanes, high-energy molecules that could potentially be used in the sustainable production of novel bioactive compounds and advanced biofuels. "We can now perform these interesting reactions inside the bacterial cell. The cells produce all of the reagents and the cofactors, which means that you can scale this reaction to very large scales" for mass manufacturing, Keasling said. -- Recruiting bacteria to synthesize chemicals could also play an integral role in reducing carbon emissions, Huang said. According to other Berkeley Lab researchers, close to 50% of greenhouse gas emissions come from the production of chemicals, iron and steel, and cement. Limiting global warming to 1.5 degrees Celsius above pre-industrial levels will require severely cutting greenhouse gas emissions in half by 2030, says a recent report by the Intergovernmental Panel on Climate Change. -- Huang said that while this fully integrated system can be envisioned for a large number of carbene donor molecules and alkene substrates, it is not yet ready for commercialization. -- "For every new advance, someone needs to take the first step. And in science, it can take years before you succeed. But you have to keep trying -- we can't afford to give up. I hope our work will inspire others to continue searching for greener, sustainable biomanufacturing solutions," Huang said. [] Greenhouse gas, Fossil fuel, Energy development, Alternative fuel vehicle, Bacteria, Carbon dioxide, United Nations Framework Convention on Climate Change, Methane | 2319-E004 |
| 124 | 2319-E037 | E01 E03 E04 | Water Warming Affects Fish Size | The widely held belief that water-breathing animals such as fish will shrink due to global warming has been challenged by new research findings. | eLife | eLife | The theory that water-breathing animals such as fish will shrink due to global warming has been called into question by a study published today in eLife. -- The study found that warm water pollution increased growth rates but also death rates, resulting in a population of younger, but larger fish. The finding is at odds in part with general predictions of the effect of warming on natural ecosystems and highlights that these need to be tested in large-scale experiments. -- As aquatic ecosystems become warmer, it is predicted that animals such as fish will grow faster at a young age but reach smaller body sizes as adults. This pattern has mainly been observed in small-scale experiments, and although some studies have tested this prediction in natural environments, these have mostly been carried out on fish species subjected to fishing, where the process of fishing itself can influence growth rates and body size. -- "Studies into the effects of warming waters on fish from large-scale, semi-controlled experiments in natural settings are rare, yet they can provide unique insights," says lead author Max Lindmark, researcher at the Swedish University of Agricultural Sciences, Department of Aquatic Resources, Lysekil, Sweden. "We used a unique study system to investigate how warm water pollution has changed the death rates, growth rates and size of fish over many generations." -- The team carried out their study in an enclosed coastal bay that has received cooling water from a nuclear power plant, making it 5-10°C warmer than the surrounding waters. They compared the fish species Eurasian perch from the enclosed bay and from a reference area in the adjacent archipelago over a 24-year time period. They combined data on catches with measurements of the fishes' length-at-age (back-calculated throughout their life from "age rings" in hard structures), and then analysed these using statistical models to investigate how the warm water pollution affected the age and size of the fish populations, as well as their growth and death rates. -- While the researchers found statistically notable differences in estimated growth rates, death rates and sizes of the fish populations between the heated and reference areas, not all of these changes were as they expected. Although female perch in the warm area grew faster, as the team anticipated, they continued to do so throughout life. These fish therefore reached a large size-at-age -- approximately 7-11% larger in the heated area at any age, when compared with the reference area. Moreover, the authors say the increase in growth rate of younger fish due to warm water was so pronounced that even if death rates were higher because of warming, and resulted in a younger overall population of fish, the average size and relative abundance of larger fish was still higher in the heated area. This trend conflicts with the prediction that global warming would shrink fish over time, especially the large and old ones. In essence, ecosystem warming instead led to younger, but larger fish in this study. -- "Our study provides strong evidence for warming-induced differences in growth and death rates among a natural population of an unexploited temperate fish species exposed to 5-10°C water temperature increases for more than two decades. These effects largely, but not completely, counteract each other -- while the fish are younger, they are also larger on average," says co-author Malin Karlsson, Water Manager at the Department of Nature and Environment, County Administrative board of Västmanland, Sweden. -- "These findings highlight that generalised predictions based on theories such as the temperature-size rule may have limited use for predicting changes at a population level, and that both death rates and growth rates are important when studying temperature effects," concludes senior author Anna Gårdmark, Professor at the Swedish University of Agricultural Sciences, Department of Aquatic Resources, Uppsala, Sweden. "Although we only studied a single species, this unique climate change experiment suggests the effects of heating at the scale of a whole ecosystem, making its findings highly relevant in the context of global warming." [] Sulfur hexafluoride, Global warming controversy, Global warming, Egg (biology), Attribution of recent climate change, Climate, Atlantic sturgeon, Frog zoology | 2319-E037 |
| 125 | 2319-E012 | E03 | Archaeological Map of First Australians' Home | Scientists have used sub-surface imaging and aerial surveys to see through floodplains in the Red Lily Lagoon area of West Arnhem Land in Australia. These methods revealed how sea level rise about 8,000 years ago altered this important landscape in the Northern Territory. | Flinders University | PLOS ONE | Scientists at Flinders University have used sub-surface imaging and aerial surveys to see through floodplains in the Red Lily Lagoon area of West Arnhem Land in Northern Australia. -- These ground-breaking methods showed how this important landscape in the Northern Territory was altered as sea levels rose about 8,000 years ago. -- Their discovery shows that the ocean had reached this, now inland region, which has important implications for understanding the archaeological record of Madjedbebe -- the oldest archaeological site in Australia. -- The findings also provide a new way to understand the rock art in the region, which is recognised globally for its significance and distinctive style. -- By examining how sediments now buried beneath the flood plains changed as sea levels rose, the researchers can see how the transformation of Red Lily Lagoon had resulted in the growth of mangroves that have supported animal and marine life in a region where ancient Indigenous rock art is located. This transformation has, in turn, fostered an environment that has inspired the subjects and animals in the ancient rock art. -- In their findings published in in the scientific journal PLOS ONE today, the researchers say environmental changes at the lagoon are reflected in the rock art because fish, crocodiles and birds were featured in the art when the floodplain transformed to support freshwater habitats for new species. -- Senior Author and Research Associate in the College of Humanities, Arts, and Social Sciences at Flinders University, Dr Jarrad Knowlessar, says the mapping fundamentally changes our archaeological understanding of the stunning landscape in Arnhem Land. -- "This is a key landscape for understanding the early human occupation of Australia. Our reconstruction of Red Lily Lagoon enables effective predictive modelling of prominent cultural sites and provides an important method to interpret the presence and provenance of Indigenous cultural material." -- "The timing of rock art aligns with the broader environmental changes we understand took place in this landscape. This is evident through changes in subject matter in the art, such as large macropods, and the appearance of estuarine animal species such as fish and crocodiles in the art. The inclusion of freshwater species, such as fish and birds, occurs in the most recent artistic styles of this region, and this reflects the phases of environmental change when the freshwater floodplains made up the landscape." -- "Based on the results of this study, all Pleistocene sites in western Arnhem Land were near the ocean and, subsequently, mangrove swamps at some point during the transformation of the landscape. This has important implications for the paleogeographic settings of these sites, which must be considered when interpreting changes in stone artefacts, food resources, and the isotope composition of materials from this period of the first Australians." [] Sea level, Antarctic ice sheet, Neandertal interaction with Cro-Magnons, Homo (genus), Aerial photography, Greenland ice sheet, Geology of the Capitol Reef area, Breaking wave | 2319-E012 |
| 126 | 2319-E020 | E01 E04 | Seagrass Meadows Bounce Back After Die-Offs | A study in Florida Bay, one of the largest global contiguous seagrass systems, found that turtlegrass can successfully recruit into open bare sediment following die-off events due to biomass partitioning. | Florida Atlantic University | Aquatic Botany | In Florida alone, thousands of acres of marine seagrass beds have died. Major seagrass die-offs also are occurring around the world. Stressors such as high temperature, hypersalinity and hypoxia or lack of oxygen affect seagrasses' ability to resist and recover from these stressor-related mortality events or when disturbances lead to seagrass die-off events. -- Seagrass die-offs also are linked to exposure to sediment-derived hydrogen sulfide, a well-known phytotoxin that accumulates as seagrass ecosystems become more enriched in nutrients. While hydrogen sulfide intrusion into seagrass tissue is considered a leading cause of recurring mortality events, its effects on subsequent recruitment and distribution of new populations is unclear. Moreover, few studies have examined the ability of seagrass meadows' resilience to "bounce back" and recolonize in open bare patches. -- Researchers from Florida Atlantic University, in collaboration with the South Florida Water Management District, Coastal Ecosystems Division, examined if porewater hydrogen sulfide prevents Thalassia testudinum, a dominant tropical Atlantic-Caribbean marine seagrass known as turtlegrass, from recruiting into unvegetated sediment in Florida Bay. The bay is an estuary that covers about 1,100 square miles between the southern tip of Florida and the Florida Keys and is one of the largest global contiguous seagrass systems. -- Since the 1980s, seagrass meadows in Florida Bay have experienced repeated biomass losses, including massive die-off events of turtlegrass, which typically occur during high temperature and salinity conditions in the northcentral and western bay. The bay provided an excellent case-study site due to high porewater hydrogen sulfide and expansive unvegetated areas adjacent to intact meadows that are recolonized by turtlegrass recruits following morality events. -- For the study, researchers examined the leaf, stems and root tissue of turtlegrass in Florida Bay to establish tissue exposure to hydrogen sulfide in new recruits and measured internal hydrogen sulfide and oxygen dynamics using cutting-edge microsensors in the field and stable isotope analyses. -- Results, published in the journal Aquatic Botany, provide evidence that turtlegrass can successfully recruit into open bare sediment following die-off events due to biomass partitioning -- a process by which plants divide their energy among their leaves, stems, roots and reproductive parts -- during early development, young root structure, and an ability to efficiently oxidize internally, which lowers hydrogen sulfide exposure. However, recovery of seagrass meadows takes time. -- "Long-term monitoring programs in Florida Bay indicate that the time frame for full recovery of turtlegrass meadows after major die-off events is at least a decade," said Marguerite Koch, Ph.D., senior author and a professor of biological sciences in FAU's Charles E. Schmidt College of Science. "Therefore, preventing large-scale seagrass mortality events should be the management goal, particularly as global warming and associated stressors are likely to get more extreme in the future." -- Findings of the study indicate that recruiting shoot resistance to hydrogen sulfide exposure is linked to adequate oxidation of internal tissue during the day through late afternoon via photosynthesis and internal plant oxidation promoted by water column oxygen diffusion into the leaves at night, driven at times by tides. Limited belowground root development in new recruits potentially constrains microbial community development and associated sulfate reduction that decrease hydrogen sulfide intrusion into roots and negatively affecting sensitive growing tissue at the base of the seagrass leaves. -- "Seagrass meadows sustain coastal ecosystems by protecting against erosion, maintaining water quality and providing habitat and food for many marine species and organisms," said Koch. "Because of their importance in coastal communities, the current decline of seagrass ecosystems on a global scale across geographic regions is a concern." -- This research was funded by the United States Department of Interior (P18AC00812) and the South Florida Water Management District (PO 450-01-20159). [] Seagrass, Timeline of environmental events, Larsen Ice Shelf, Annual sedimentary layer, Dead zone (ecology), Air pollution, Wetland, Meteorology | 2319-E020 |
| 127 | 2319-E005 | E01 | Enzyme Evolution's Mysteries | Researchers have made a major breakthrough in the field of evolutionary conservation of molecular dynamics in enzymes, which could lead to the development of new drugs to treat serious diseases like cancer or to counter antibiotic resistance. | Institut national de la recherche scientifique - INRS | Structure | Professor Nicolas Doucet and his team at Institut national de la recherche scientifique (INRS) made a major breakthrough earlier this year in the field of evolutionary conservation of molecular dynamics in enzymes. Their work, published in the journal Structure, points to potential applications in health, including the development of new drugs to treat serious diseases such as cancer or to counter antibiotic resistance. -- As a researcher specializing in protein dynamics, Professor Doucet is captivated by things that are invisible to the naked eye, yet full of mysteries and essential to all forms of life. He studies proteins and enzymes, and the poorly understood links between their structure, function, and motion at the atomic scale. -- To better envision unexplored avenues of enquiry, the enzyme engineering specialist starts by examining problems from a conceptual standpoint. -- "A bit of imagination may be all it takes to envision multiple paths of enquiry in this tiny world we still know relatively little about, but the scientific process is very meticulous," said Professor Doucet, a researcher at the Armand-Frappier Santé Biotechnologie Research Centre and scientific co-head of the Nuclear Magnetic Resonance Spectroscopy Lab at INRS. -- Towards a better understanding of macromolecular function -- As part of this study, Professor Doucet's team investigated an issue considered fundamental by experts in the field: if a particular protein or enzyme relies on the conformational change of its three-dimensional structure to perform its biological function in humans, do homologous enzymes in other vertebrates or other living organisms also depend on these same conformational changes? In other words, if certain motions are essential to the biological function of proteins and enzymes, are these conformation changes selected and conserved as a molecular evolutionary mechanism in all forms of life? -- Despite our very limited understanding of how these macromolecules essential to life on Earth actually work, the team attempted to answer this question. -- Developments in biochemical and biophysical technology in recent decades have made it easier to observe the molecular structures of proteins and enzymes. -- "We studied different enzymes of the same family to analyze several proteins exhibiting the same biological function. We compared their atomic-scale motions to uncover whether they are preserved throughout evolution. Despite overall similarities between species, we were surprised to find that, on the contrary, movements are divergent," explained the lead author of the study, David Bernard, an INRS graduate who was a PhD student in Professor Doucet's lab at the time. He now works as a researcher at NMX. -- Molecular motions of great importance [] Molecular biology, Antibiotic resistance, Enzyme, Vaccination, Cancer, Linus Pauling, Garlic, Penicillin-like antibiotics | 2319-E005 |
| 128 | 2319-E023 | E03 | Basic Toolkit for Organ Development Illuminated | A recent study illumines fundamental design principles of tubulogenesis for all chordates, including mammals, which is one of the basic and crucial embryonic processes to unfold in virtually every living organism. | Marine Biological Laboratory | Nature Communications | One of the most basic and crucial embryonic processes to unfold in virtually every living organism is the formation of hollow, tubular structures of various kinds. These tubes may form blood vessels or a digestive tract, and through branching and differentiation, complex organs including the heart, kidneys, and mammary glands. Abnormalities in these processes can cause congenital disorders such as dysfunctional, displaced, or non-symmetrical organs, as well as regeneration defects in blood vessels or in other regenerative organs. -- Despite its fundamental importance, the general mechanisms of hollow tube formation during embryogenesis are not well understood, due to the great diversity of strategies that animals use to form tubular structures. -- Enter the sea star, an ancient marine creature whose process of tubulogenesis is relatively easy to study, and which is becoming an important organism for understanding the genetics and mechanics of tube formation. In the May 9 issue of Nature Communications, Margherita Perillo of the Marine Biological Laboratory (MBL) and collaborators reveal in detail the initiation and early stages of tube formation in the sea star Patiria miniata. -- "Most of our organs are tubular, because they need to transport fluids or gases or food or blood. And more complex organs like the heart start as a tube and then develop different structures. So, tubulogenesis is a very basic step to form all our organs," Perillo said. -- Perillo chose the sea star as a research organism "because I wanted to understand the basic mechanism of tube formation that is conserved across all vertebrates. So I needed an animal that was at the base along the tree of life, [evolving] before the chordates," she said. -- Using CRISPR and other techniques to analyze gene function, as well as long time-lapse movies of the developing sea star larvae, Perillo and colleagues ascertained how this organism generates tubes that branch out from its gut. Her study defines a basic toolkit from which the chordate tubular organs may have developed. (Chordates include the vertebrates -- fish, amphibians, reptiles, birds and mammals -- and a few invertebrate subphyla). -- One open question in biology was exactly how organisms develop from one cell into the complex 3D tubular structures of various organs, Perillo said. In some organisms such as flies, "there is a big round of cell proliferation before all the cells start to make very complex migration patterns to elongate, change their shapes, and become a tube," she said. In other animals, including mammals, cell proliferation and migration occur together. In the case of the sea star, "I found that, in order for tube formation, cells can proliferate and migrate at the same time," as they do in vertebrate development. "So, this means that this mechanism of making organs was already established at the base" or root of the evolution of chordates, she said. -- In addition to providing insights into the fundamental process that leads to organ formation, sea stars can serve as a model for much biomedical research, Perillo suggests. For example, she found that a gene called Six1/2 serves as a key regulator of the branching process in tube formation. In mice, knocking out Six1/2 causes kidneys to form abnormally. But researchers have found that mice lacking this gene also resist tumor formation, even when injected with tumor cells. The gene, which is overexpressed in cancer cells, could lead to new ways of studying disease progression, including cancer. -- "I can now use this gene to understand not only how our organs develop, but what happens to organs when we have a disease, especially cancer," she says. "My hope is that, in five to 10 years maximum, we will be able to use this gene to test how organs develop cancer and how cancer becomes metastatic." -- Sea star embryos have many practical experimental advantages, Perillo said. They are mostly transparent, so internal growth processes can be directly observed over long developmental periods without harming the organism. They are also easy to collect and breed in large numbers year-round, "so I always have a lot of material to work with." [] Developmental biology, Biology, Blood vessel, Vertebrate, Vein, Coronary circulation, Gastrointestinal tract, Kidney | 2319-E023 |
| 129 | 2319-E003 | E05 | Unprecedented View of Gene Regulation | Using a new technique, researchers have been able to map interactions between gene promoters and enhancers with 100 times higher resolution than previously possible. | Massachusetts Institute of Technology | Nature Genetics | Much of the human genome is made of regulatory regions that control which genes are expressed at a given time within a cell. Those regulatory elements can be located near a target gene or up to 2 million base pairs away from the target. -- To enable those interactions, the genome loops itself in a 3D structure that brings distant regions close together. Using a new technique, MIT researchers have shown that they can map these interactions with 100 times higher resolution than has previously been possible. -- "Using this method, we generate the highest-resolution maps of the 3D genome that have ever been generated, and what we see are a lot of interactions between enhancers and promoters that haven't been seen previously," says Anders Sejr Hansen, the Underwood-Prescott Career Development Assistant Professor of Biological Engineering at MIT and the senior author of the study. "We are excited to be able to reveal a new layer of 3D structure with our high resolution." -- The researchers' findings suggest that many genes interact with dozens of different regulatory elements, although further study is needed to determine which of those interactions are the most important to the regulation of a given gene. -- "Researchers can now affordably study the interactions between genes and their regulators, opening a world of possibilities not just for us but also for dozens of labs that have already expressed interest in our method," says Viraat Goel, an MIT graduate student and one of the lead authors of the paper. "We're excited to bring the research community a tool that help them disentangle the mechanisms driving gene regulation." -- MIT postdoc Miles Huseyin is also a lead author of the paper, which appears today in Nature Genetics. -- High-resolution mapping -- Scientists estimate that more than half of the genome consists of regulatory elements that control genes, which make up only about 2 percent of the genome. Genome-wide association studies, which link genetic variants with specific diseases, have identified many variants that appear in these regulatory regions. Determining which genes these regulatory elements interact with could help researchers understand how those diseases arise and, potentially, how to treat them. -- Discovering those interactions requires mapping which parts of the genome interact with each other when chromosomes are packed into the nucleus. Chromosomes are organized into structural units called nucleosomes -- strands of DNA tightly wound around proteins -- helping the chromosomes fit within the small confines of the nucleus. -- Over a decade ago, a team that included researchers from MIT developed a method called Hi-C, which revealed that the genome is organized as a "fractal globule," which allows the cell to tightly pack its DNA while avoiding knots. This architecture also allows the DNA to easily unfold and refold when needed. [] Electron microscope, Gene, Molecular biology, Positron emission tomography, Blue Gene, Bioinformatics, Conflict resolution, Transmission electron microscopy | 2319-E003 |
| 130 | 2319-E014 | E03 E04 | Chemical Signal Protects Migratory Locusts | Scientists have discovered that the migratory locust, Locusta migratoria, produces the compound phenylacetonitrile (PAN) to defend itself against feeding attacks by conspecifics as population density increases. The discovery of an anti-cannibalism pheromone offers new approaches for locust control. | Max Planck Institute for Chemical Ecology | Science | Huge swarms of migratory locusts take on the proportions of natural disasters and threaten the food supply of millions of people, especially in Africa and Asia. As the eighth of the ten biblical plagues, the Book of Moses in the Old Testament already describes how swarms of locusts darkened the sky and ate up everything that grew in the fields and on the trees. Scientists suspect that cannibalism among locusts contributes to their swarming behavior, and swarms therefore constantly move on because individual animals are always on the run from conspecifics pursuing them. "We wondered how these insects influence each other's behavior within huge swarms, and whether olfaction plays a role. An important basis for us was the research on the formation of locust swarms by Iain Couzin of the Max Planck Institute for Behavioral Biology in Constance," says study leader Bill Hansson, director of the Department of Evolutionary Neuroethology at the Max Planck Institute, explaining the starting point of the study. -- Migratory locusts occur in different phases: In the solitary phase, the insects live individually and stay in the area, while in the gregarious phase they exhibit the typical swarming behavior that fits their denomination as migratory locusts. "In most cases, locusts are in the solitary phase, where they avoid physical contact with conspecifics and eat comparatively little food. If the population density increases due to rainfall and sufficient food, the locusts change their behavior within a few hours; they can smell, see, and touch each other. These three types of stimulation increase serotonin and dopamine levels in the locust brain, causing solitary locusts to become aggressive gregarious locusts that are very active and have a large appetite. They also release aggregation pheromones, which eventually leads to swarming and poses a huge threat to agricultural production. Cannibalism does only occur in the gregarious phase," explains the study's first author Hetan Chang. -- Behavioral experiments with the migratory locust Locusta migratoria showed that cannibalism rates increased with the number of gregarious animals that were kept together in a cage. Thus, there is a direct relationship between population density and cannibalistic behavior. To find out if gregarious locusts emit particular odors that are not produced in the solitary phase, the research team analyzed and compared all odors emitted by solitary and gregarious locust in the juvenile stage. Of the 17 odors produced exclusively in the gregarious phase, only phenylacetonitrile (PAN) turned out to be an odor signal that deterred other locusts in behavioral tests. For further confirmation of PAN's function, the scientists used genetically modified locusts that could no longer produce PAN. "We showed that as population density increased, not only did the level of cannibalism rise, but the animals also produced more PAN. Using genome editing, we were able to knock out an enzyme responsible for the production of this compound. This allowed us to confirm its strong anti-cannibalistic effect, because cannibalism was again significantly increased when the animals were no longer able to produce the compound," says Hetan Chang. -- The biggest challenge was finding the olfactory receptor that recognizes PAN. Since locusts have more than 140 olfactory receptor genes, the research team had to clone as many genes as possible and test them one by one. Tests on 49 different olfactory receptors using more than 200 relevant odors eventually led to the identification of the olfactory receptor OR70a as a highly sensitive and specific detector of PAN in the migratory locust Locusta migratoria. Behavioral experiments with genetically modified locusts whose OR70a receptor was no longer functioning again showed a strongly increased cannibalism rate, which is due to the fact that the cannibalism stop signal can no longer be perceived by the locusts without the corresponding receptor. -- A pheromone that controls cannibalism is an absolute new discovery. Because cannibalism has a major impact on locust swarm dynamics, a fundamental understanding of the population ecology of these animals, particularly the effect of PAN, opens up new possibilities of locust control. "If you inhibit the production of PAN or the function of the receptor, you could get the locusts to behave more cannibalistically and potentially control themselves in that way," Bill Hansson says. [] Bonobo, Chimpanzee, Common Chimpanzee, Chronic pain, Dog intelligence, Excitotoxicity and cell damage, Tortoise, Population dynamics of fisheries | 2319-E014 |
| 131 | 2319-E018 | E04 | Cultural Continuity at Oldest Site in West Africa | Recent discoveries of stone tools near the Senegalese coast extend occupation of the region back to 150 thousand years ago and are comparable to those seen across Africa at this time, but uniquely persist in the region until 10 thousand years ago. | Max Planck Institute of Geoanthropology | Nat Ecol Evol | Evidence from West Africa about human evolution remains scarce, but recent research has indicated unique patterns of cultural change in comparison to other regions of the continent. A new article in the journal Nature Ecology and Evolution adds to our understanding with a study of the oldest directly dated archaeological site in West Africa. The site shows technological continuity spanning roughly 140,000 years and offers insights into the ecological stability of the region. -- Our species emerged in Africa around 300 thousand years ago and until around 30-60 thousand years ago typically used tools and tool-making techniques referred to as Middle Stone Age toolkits. Around that time, distinct Later Stone Age toolkits began to emerge in northern, eastern, and southern Africa. While recent evidence suggests Middle Stone Age toolkits persisted in West Africa much later, to around 10 thousand years ago, the antiquity of these technologies is poorly understood. -- The new study, led by scientists from the Max Planck Institute of Geoanthropology, Université Cheikh Anta Diop de Dakar, University of Sheffield, and University of South Florida, extends the timeframe in which Middle Stone Age toolkits are known from West Africa to 150 thousand years ago, based on excavations from the near-coastal site of Bargny 1. -- “The stone tool assemblage dating from 150 thousand years ago shows classic features of the Middle Stone Age, with the use of Levallois and discoidal reduction methods and the use of small retouched flake tools rather than larger implements,” says Dr Khady Niang, lead author of the study. “The assemblage from Bargny 1 is closely comparable to those of a similar age from across the continent, and is the first site from West Africa dating to the Middle Pleistocene, prior to the onset of substantial technological regionalization elsewhere in Africa.” -- The site itself is located close to the modern coastline, south of Dakar, Senegal. While no artefacts indicating direct human engagement with coastal resources were recovered at the site, study of the associated environments offer a wider perspective. -- “We found mangrove and brackish wetland plant microfossils associated with the site’s occupation,” adds Dr Chris Kiahtipes of the University of South Florida, co-author on the study. “This is particularly interesting because it shows that the site was located near an estuary and demonstrates how important these habitats are to humans past and present.” -- The study highlights long-term durability of core elements of Middle Stone Age toolkits in West Africa without evidence for the appearance of specialized technological developments observed elsewhere. -- “Middle Stone Age populations adapted to a wide range of habitats and engaged with climatic changes across Africa. But in West Africa, we see considerable environmental stability over the past 150 thousand years,” adds Dr Jimbob Blinkhorn. “One explanation for the enduring cultural continuity we observe is that it was a stable behavioural adaptation to stable environmental conditions, whilst potential isolation from other populations across Africa may have led to demographic stability too. Ultimately, our study helps illustrate the persistent utility of Middle Stone Age technologies to inhabit the diverse habitats found across Africa.” [] Stone Age, Homo heidelbergensis, Neandertal interaction with Cro-Magnons, Homo (genus), Homo ergaster, Recent single-origin hypothesis, Mammoth, Stone tool | 2319-E018 |
| 132 | 2319-E013 | E01 | Quantum Lidar Prototype for Underwater Images | Researchers have developed a prototype lidar system that uses quantum detection technology to acquire 3D images while submerged underwater. This system's high sensitivity could allow it to capture detailed information even in extremely low-light conditions found underwater. | Optica | Optics Express | For the first time, researchers have demonstrated a prototype lidar system that uses quantum detection technology to acquire 3D images while submerged underwater. The high sensitivity of this system could allow it to capture detailed information even in extremely low-light conditions found underwater. -- "This technology could be useful for a wide range of applications," said research team member Aurora Maccarone, a Royal Academy of Engineering research fellow from Heriot-Watt University in the United Kingdom. "For example, it could be used to inspect underwater installations, such as underwater wind farm cables and the submerged structure of the turbines. Underwater lidar can also be used for monitoring or surveying submerged archaeology sites and for security and defense applications." -- Obtaining 3D images through ocean water can be challenging because it is light-limited, and any particles in the water will scatter light and distort the image. However, single-photon detection, which is a quantum-based technique, allows very high penetration and works even in low-light conditions. -- In the Optica Publishing Group journal Optics Express, researchers from Heriot-Watt University and the University of Edinburgh describe experiments in which an entire single-photon lidar system was submerged in a large water tank. The new demonstrations bring the technology closer to practical applications compared to the research team's earlier experiments with underwater single-photon detection, which were performed in carefully controlled laboratory conditions with the optical setup placed outside the water tank and data analysis performed offline. They also implemented new hardware and software developments that allow the 3D images acquired by the system to be reconstructed in real time. -- "This work aims to make quantum detection technologies available for underwater applications, which means that we will be able to image the scene of interest in very low light conditions," said Maccarone. "This will impact the use of offshore cable and energy installations, which are used by everyone. This technology could also allow monitoring without the presence of humans, which would mean less pollution and a less invasive presence in the marine environment." -- Faster low-light detection -- Lidar systems create images by measuring how long it takes laser light to be reflected from objects in the scene and travel back to the system's receiver, known as the "time of flight." In the new work, the researchers sought to develop a way to acquire 3D images of targets that are obscured by turbid water and thus not visible to conventional lidar imaging systems. -- They designed a lidar system that uses a green pulsed laser source to illuminate the scene of interest. The reflected pulsed illumination is detected by an array of single-photon detectors, which allows ultrafast low light detection and greatly reduces measurement time in photon-starved environments such as highly attenuating water. -- "By taking time-of-flight measurements with picosecond timing resolution, we can routinely resolve millimeter details of the targets in the scene," said Maccarone. "Our approach also allows us to distinguish the photons reflected by the target from those reflected by particles in the water, making it particularly suitable to performing 3D imaging in highly turbid waters where optical scattering can ruin image contrast and resolution." -- The fact that this approach requires thousands of single-photon detectors, all producing many hundreds of events per second, makes it extremely challenging to retrieve and process the data necessary to reconstruct the 3D image in a short time, especially for real-time applications. To solve this problem, the researchers developed algorithms specifically for imaging in highly scattering conditions and applied them in conjunction with widely available graphics processing unit (GPU) hardware. [] Quantum entanglement, Quantum number, Underwater explosion, Hurricane, Cruise missile, Tide, Computer simulation, Dynamite | 2319-E013 |
| 133 | 2319-E016 | E01 E02 E04 | Atmospheric Dust's Role in Oceans | New research begins to unravel the role dust plays in nourishing global ocean ecosystems while helping regulate atmospheric carbon dioxide levels. | Oregon State University | Science | New research led by an Oregon State University scientist begins to unravel the role dust plays in nourishing global ocean ecosystems while helping regulate atmospheric carbon dioxide levels. -- Researchers have long known that phytoplankton -- plantlike organisms that live in the upper part of the ocean and are the foundation of the marine food web -- rely on dust from land-based sources for key nutrients. But the extent and magnitude of the impact of the dust -- particles from sources such as soil that are lifted by the wind and impact the Earth's climate -- have been difficult to estimate globally. -- "This is really the first time it has been shown, using the modern observational record and at the global scale, that the nutrients carried by dust being deposited on the ocean are creating a response in the surface ocean biology," said Toby Westberry, an oceanographer at Oregon State and lead author of the just-published paper in Science. -- The ocean plays an important role in the carbon cycle; carbon dioxide from the atmosphere dissolves in surface waters, where phytoplankton turn the carbon into organic matter through photosynthesis. Some of the newly formed organic matter sinks from the surface ocean to the deep sea, where it is locked away, a pathway known as the biological pump. -- In the new paper, Westberry and other scientists from Oregon State; University of Maryland, Baltimore County; and NASA Goddard Space Flight Center estimate deposition of dust supports 4.5% of the global annual export production, or sink, of carbon. Regional variation in this contribution can be much higher, approaching 20% to 40%, they found. -- "That's important because it's a pathway to get carbon out of the atmosphere and down into the deep ocean," Westberry said. "The biological pump is one of the key controls on atmospheric carbon dioxide, which is a dominant factor driving global warming and climate change." -- In the ocean, vital nutrients for phytoplankton growth are largely provided through the physical movement of those nutrients from deep waters up to the surface, a process known as mixing or upwelling. But some nutrients are also provided through atmospheric dust. -- To date, the understanding of the response by natural marine ecosystems to atmospheric inputs has been limited to singularly large events, such as wildfires, volcanic eruptions and extreme dust storms. In fact, previous research by Westberry and others examined ecosystem responses following the 2008 eruption on Kasatochi Island in southwestern Alaska. -- In the new paper, Westberry and Michael Behrenfeld, an Oregon State professor in the Department of Botany and Plant Pathology, along with scientists from UMBC and NASA built on this past research to look at phytoplankton response worldwide. -- Westberry and Behrenfeld focused their efforts on using satellite data to examine changes in ocean color following dust inputs. Ocean color imagery is collected across the global ocean every day and reports changes in the abundance of phytoplankton and their overall health. For example, greener water generally corresponds to abundant and healthy phytoplankton populations, while bluer waters represent regions where phytoplankton are scarce and often undernourished. [] Forest, Ocean acidification, Carbon dioxide sink, Global climate model, Carbon dioxide, Fossil fuel, Acid rain, Climate change mitigation | 2319-E016 |
| 134 | 2319-E033 | E04 | Biofortification of Microgreens with Zinc | Biofortified seeds of plants such as peas and sunflowers contain high levels of zinc, which can help mitigate global malnutrition. Microgreens harvested from these seeds can also improve the chances of survival during a catastrophe. | Penn State | Frontiers in Plant Science | When the seeds of plants such as pea and sunflower are biofortified with zinc, the seedlings they quickly produce -- harvested as microgreens -- could both help to mitigate global malnutrition and boost the odds of people surviving a catastrophe. -- That's the conclusion of a Penn State research team that experimented with several biofortification methods to determine the most effective way to incorporate a mineral essential to human health into the young plants while not diminishing the amounts of other essential nutrients they produce. Microgreens biofortified with zinc offer people a lifeline in the face of starvation risk, according to team leader Francesco Di Gioia, assistant professor of vegetable crop science. -- "This study has demonstrated that zinc biofortification through seed nutri-priming achieves needed levels of zinc in the young pea and sunflower plants we focused our experiments on," he said. "These results have implications for both global 'hidden hunger' and emergency or catastrophe preparedness." -- The work is another development in the ongoing project "Food Resilience in the Face of Catastrophic Global Events," funded by the nonprofit foundation Open Philanthropy. In Di Gioia's work, an international team of researchers found that microgreens can be grown in a variety of soilless production systems in small spaces indoors, with or without artificial lighting. The zinc biofortification component is an important new innovation. -- Biofortification is the process of growing crops to increase nutritional value from the seed on, Di Gioia explained. It is different from food fortification, which involves adding nutrients to foods during post-harvest processing. In poor regions of the world, or under post-catastrophic conditions, simply soaking seeds in a zinc solution is a practical and effective strategy for producing nutrient-dense microgreens, he pointed out. -- "Starting decades ago as fashionable, high-value gourmet greens, microgreens today have gained popularity among consumers for their nutritional profile and high content of antioxidant compounds," he said. "Our work shows microgreens can help people to survive a global catastrophe such as all-out nuclear war, a large asteroid strike or supervolcano eruption in the short term, but additional nutritional resources may be needed in the longer term." -- Such a cataclysmic event would endanger agricultural productivity by reducing sunlight and temperature, disrupting rainfall patterns, and contaminating water supplies, thus threatening starvation for survivors of the initial event. Early on, biofortified microgreen production could improve the probability of human survival under these conditions. -- The prospect of also being able to expeditiously mitigate hidden hunger excites Pradip Poudel, the second-year doctoral degree student in the College of Agricultural Sciences who spearheaded the research. He suggested that production of nutrient-dense crops using agronomic biofortification techniques is a sustainable strategy that is badly needed to address malnutrition. -- The World Health Organization defines "hidden hunger" as a lack of vitamins and minerals that occurs when the quality of food people eat does not meet the nutrient requirements they need for their growth and development, Poudel noted. Two billion people suffer from vitamin and mineral deficiencies, according to the WHO. -- "We were thinking, how can we increase the content of zinc in microgreens, developing a very simple way that people could use at home in a 'microgreens growing kit' that could be delivered in an emergency situation," he said. "And we know it will be important to include a fertilizer source for zinc so people will just have to soak the seeds before putting them in germination -- a very simple process that anyone can do to enrich their microgreens with zinc." [] Flower, Plant breeding, Vitamin E, Gymnosperm Plants, Seed predation, Asteraceae, Spore | 2319-E033 |
| 135 | 2319-E015 | E01 E02 | Clues About Rise of Earth's Continents | New research has tested and ultimately eliminated one popular hypothesis about why continental crust contains less iron and is more oxidized than oceanic crust. The iron-poor composition of continental crust is a significant reason why vast portions of the Earth's surface stand above sea level as dry land, making terrestrial life possible today. | Smithsonian | Science | Continents are part of what makes Earth uniquely habitable for life among the planets of the solar system, yet surprisingly little is understood about what gave rise to these huge pieces of the planet's crust and their special properties. New research from Elizabeth Cottrell, research geologist and curator of rocks at the Smithsonian's National Museum of Natural History, and lead study author Megan Holycross, formerly a Peter Buck Fellow and National Science Foundation Fellow at the museum and now an assistant professor at Cornell University, deepens the understanding of Earth's crust by testing and ultimately eliminating one popular hypothesis about why continental crust is lower in iron and more oxidized compared to oceanic crust. The iron-poor composition of continental crust is a major reason why vast portions of the Earth's surface stand above sea level as dry land, making terrestrial life possible today. -- The study, published today in Science, uses laboratory experiments to show that the iron-depleted, oxidized chemistry typical of Earth's continental crust likely did not come from crystallization of the mineral garnet, as a popular explanation proposed in 2018. -- The building blocks of new continental crust issue forth from the depths of the Earth at what are known as continental arc volcanoes, which are found at subduction zones where an oceanic plate dives beneath a continental plate. In the garnet explanation for continental crust's iron-depleted and oxidized state, the crystallization of garnet in the magmas beneath these continental arc volcanoes removes non-oxidized (reduced or ferrous, as it is known among scientists) iron from the terrestrial plates, simultaneously depleting the molten magma of iron and leaving it more oxidized. -- One of the key consequences of Earth's continental crust's low iron content relative to oceanic crust is that it makes the continents less dense and more buoyant, causing the continental plates to sit higher atop the planet's mantle than oceanic plates. This discrepancy in density and buoyancy is a major reason that the continents feature dry land while oceanic crusts are underwater, as well as why continental plates always come out on top when they meet oceanic plates at subduction zones. -- The garnet explanation for the iron depletion and oxidation in continental arc magmas was compelling, but Cottrell said one aspect of it did not sit right with her. -- "You need high pressures to make garnet stable, and you find this low-iron magma at places where crust isn't that thick and so the pressure isn't super high," she said. -- In 2018, Cottrell and her colleagues set about finding a way to test whether the crystallization of garnet deep beneath these arc volcanoes is indeed essential to the process of creating continental crust as is understood. To accomplish this, Cottrell and Holycross had to find ways to replicate the intense heat and pressure of the Earth's crust in the lab, and then develop techniques sensitive enough to measure not just how much iron was present, but to differentiate whether that iron was oxidized. -- To recreate the massive pressure and heat found beneath continental arc volcanoes, the team used what are called piston-cylinder presses in the museum's High-Pressure Laboratory and at Cornell. A hydraulic piston-cylinder press is about the size of a mini fridge and is mostly made of incredibly thick and strong steel and tungsten carbide. Force applied by a large hydraulic ram results in very high pressures on tiny rock samples, about a cubic millimeter in size. The assembly consists of electrical and thermal insulators surrounding the rock sample, as well as a cylindrical furnace. The combination of the piston-cylinder press and heating assembly allows for experiments that can attain the very high pressures and temperatures found under volcanoes. -- In 13 different experiments, Cottrell and Holycross grew samples of garnet from molten rock inside the piston-cylinder press under pressures and temperatures designed to simulate conditions inside magma chambers deep in Earth's crust. The pressures used in the experiments ranged from 1.5 to 3 gigapascals -- that is roughly 15,000 to 30,000 Earth atmospheres of pressure or 8,000 times more pressure than inside a can of soda. Temperatures ranged from 950 to 1,230 degrees Celsius, which is hot enough to melt rock. -- Next, the team collected garnets from Smithsonian's National Rock Collection and from other researchers around the world. Crucially, this group of garnets had already been analyzed so their concentrations of oxidized and unoxidized iron were known. [] Continental crust, Crust (geology), Structure of the Earth, Lithosphere, Ocean, Volcano, Quartz, Earth | 2319-E015 |
| 136 | 2319-E017 | E01 E03 | Seagrass Meadows Resilient After Die-Offs | A new global study of more than 1,200 marine locations over a 16-year period reveals that using the amount of seaweed at the ocean's surface as a proxy for the health of coral reefs below has been misleading and may even have hidden signs of reef stress. | University of British Columbia | Global Change Biology | For decades, scientists have looked to seaweed as an indicator of the health of coral reefs lying underneath. -- But what if the seaweed was misleading them? -- New UBC research reveals it was, and scientists need new ways to determine whether human activity is harming a particular reef. -- "This is especially critical today, given that reefs globally are threatened by climate-driven stressors," said Dr. Sara Cannon, a postdoctoral fellow at the UBC Institute for the Oceans and Fisheries and the study's lead author. -- Local species behave differently -- Seaweed belongs to a group of organisms called macroalgae. Macroalgae at the ocean's surface has long served as a proxy for reef health, because it is relatively quick and easy to measure. Since the 1970s, scientists have assumed that local human impacts increase macroalgae while simultaneously damaging underlying reefs. -- However, the study just published in Global Change Biology looked at data from over 1,200 sites in the Indian and Pacific Oceans over a 16-year period and revealed that this approach is misleading and may even have hidden signs of reef stress. -- For example, macroalgae coverage depends heavily on the species growing in a particular area. Sargassum is less likely to grow in water contaminated by agricultural runoff, but Halimeda will thrive. In both cases, a reef will suffer. -- The global research team concluded that using macroalgae coverage as an indicator of local human impacts can actually obscure how much our actions are harming reefs, and cause scientists to misidentify the reefs most in need of intervention. [] Coral reef, Artificial reef, Temperature record of the past 1000 years, Great Barrier Reef, Coral, Coral bleaching, Paleoclimatology, Dinoflagellate | 2319-E017 |
| 137 | 2319-E026 | E01 | Gulf of Mexico Wells' Cleanup Costs | An article published recently analyzes the expenses associated with closing down 14,000 oil wells located in the Gulf of Mexico. These wells have been inactive for more than five years and are unlikely to be reopened, posing a challenge for the U.S. offshore oil and gas industry. | University of California - Davis | Nature Energy | Wetlands, coastal areas and offshore waters near Alabama, Louisiana and Texas have more inactive oil and gas wells than producing ones, and the cost to permanently plug and abandon them could be $30 billion, University of California, Davis, researchers suggest. -- A paper published today in the journal Nature Energy examines the cost to plug 14,000 wells that are inactive, have not produced for five years and are unlikely to be reactivated in the Gulf of Mexico region, which is the epicenter of U.S. offshore oil and gas operations. -- The wells could pose future environmental and financial risks to the public, and the cost differential for plugging onshore wells versus those in offshore waters is large, said Mark Agerton, an assistant professor at UC Davis and lead author of the paper. -- Leaks from wells closer to shore are more likely to damage coastal ecosystems and release greenhouse gases like methane into the atmosphere, compared to wells in deep waters. The study found that more than 90% of inactive wells are in shallow areas, and the cost to plug those would be $7.6 billion, or 25% of a total $30 billion. -- Informing policy decisions -- "The wells aren't supposed to be leaking into the environment, but sometimes they do," said Agerton, of the Department of Agricultural and Resource Economics. "How do you get the most environmental benefit for the least amount of money?" -- The findings could help states decide cleanup priorities, especially as they access $4.7 billion in federal money authorized by the Infrastructure Investment and Jobs Act. That money is set aside for methane reduction programs, including cleanup of old oil and gas wells, said Gregory Upton, an associate research professor at the Louisiana State University Center for Energy Studies and co-author of the paper. -- "States have a pretty good idea of what it costs to plug these wells on land, but there is really a lot of uncertainty as to what the costs were for these offshore wells," Upton said during a media briefing about the paper. -- Liability for cleaning up wells abandoned in federal waters falls to prior owners if the current owner becomes insolvent and is unable to cover costs. Large American oil companies currently own or have owned 88% of the wells in federal Gulf of Mexico waters and would legally shoulder cleanup liabilities before taxpayers, Agerton said. -- But in state waters, each jurisdiction handles liability differently, and prior ownership doesn't come into play. States oversee plugging programs for orphaned wells whose owners have gone bankrupt, though the cost to plug an abandoned offshore well increases with the length of the well and the depth of the water. [] Hurricane Opal, Gulf of Mexico, History of Earth, Fracking, Gulf Stream, Petroleum geology, Hurricane Rita, 2005 Kashmir earthquake | 2319-E026 |
| 138 | 2319-E001 | E05 | Gene Silencing Enzyme Targets Single Molecule | Researchers have developed a DNA enzyme, called DNAzyme, that can distinguish between two RNA strands in a cell and cut the disease-associated strand while leaving the healthy strand intact. This technology could have significant implications for treating cancer, infectious diseases, and neurological disorders. | University of California - Irvine | Nature Communications | Researchers from the University of California, Irvine have developed a DNA enzyme -- or DNAzyme -- that can distinguish between two RNA strands inside a cell and cut the disease-associated strand while leaving the healthy strand intact. This breakthrough "gene silencing" technology could revolutionize the development of DNAzymes for treating cancer, infectious diseases and neurological disorders. -- DNAzymes are nucleic acid enzymes that cut other molecules. Through chemistry, UCI's team developed the Dz 46 enzyme, which specifically targets the allele-specific RNA mutation in the KRAS gene, the master regulator of cell growth and division, found in 25 percent of all human cancers. A description of how the team achieved this enzyme evolution was recently published in the online journal Nature Communications. -- "Generating DNAzymes that can effectively function in the natural conditions of cell systems has been more challenging than expected," said corresponding author John Chaput, UCI professor of pharmaceutical sciences. "Our results suggest that chemical evolution could pave the way for development of novel therapies for a wide range of diseases." -- Gene silencing has been available for more than 20 years and some FDA-approved drugs incorporate various versions of the technology, but none can distinguish a single point mutation in an RNA strand. The benefit of the Dz 46 enzyme is that it can identify and cut a specific gene mutation, offering patients an innovative, precision medicine treatment. -- The DNAzyme resembles the Greek letter omega and acts as a catalyst by accelerating chemical reactions. The "arms" on the left and right bind to the target region of the RNA. The loop binds to magnesium, and folds and cuts the RNA at a very specific site. But generating DNAzymes with robust multiple turnover activity under physiological conditions required some ingenuity, because DNAzymes are normally very dependent on concentrations of magnesium not found inside a human cell. -- "We solved that problem by re-engineering the DNAzyme using chemistry to reduce its dependency on magnesium and did so in such a way that we could maintain high catalytic turnover activity," Chaput said. "Ours is one of the very first, if not the first, example of achieving that. The next steps are to advance Dz 46 to a point that it's ready for pre-clinical trials." -- Team members Kim Thien Nguyen, project scientist, and Turnee N. Malik, postdoctoral scholar, both from the Department of Pharmaceutical Sciences, also participated in this study. -- The researchers and UCI have filed provisional patent applications on the chemical composition and cleavage preference of Dz 46. Chaput is a consultant for drug development company 1E Therapeutics, which supported this work. [] Telomere, Genetic code, Chemotherapy, DNA, Stem cell treatments, Gene, Gene therapy, Vector (biology) | 2319-E001 |
| 139 | 2319-E002 | E04 | T Cells Activate to Fight Tumors | A new auto-signaling mechanism driving the T cell anti-tumor response has been discovered by scientists. These findings may inspire new cancer therapeutics and biomarkers. | University of California - San Diego | Immunity | When you need a bit of motivation, it often has to come from within. New research suggests cancer-fighting immune cells have found a way to do just that. -- Scientists at University of California San Diego have discovered a property of T cells that could inspire new anti-tumor therapeutics. Through a previously undescribed form of cell auto-signaling, T cells were shown to activate themselves in peripheral tissues, fueling their ability to attack tumors. -- The study, published May 8, 2023 in Immunity, was led by study first author and postdoctoral fellow Yunlong Zhao, PhD, and co-senior authors Enfu Hui, PhD, professor in the School of Biological Sciences at UC San Diego and Jack D. Bui, MD, PhD, professor of pathology at UC San Diego School of Medicine. -- T cells are a type of white blood cell that protect against infection and help fight cancer. In the lymph organs, T cells are trained by antigen-presenting cells, which, as their name suggests, present an antigen (a piece of tumor or pathogen) to T cells, stimulating an immune response. -- A key part of this process is the binding of B7, a protein on the surface of antigen-presenting cells, with CD28, a receptor on T cells. This B7:CD28 interaction is a major driver of the T cell immune response. Once trained, T cells leave the lymph organs and travel through the body to find and attack their targets. -- More recent work has since revealed that T cells can actually produce their own B7 or take the B7 protein from the antigen-presenting cells and bring it along with them, but exactly why they do this has remained unclear. This also led the researchers to wonder whether T cells, now equipped with both a receptor and its ligand, might be able to activate themselves. -- Through a series of experiments, the researchers found that T cells could indeed self-activate by puckering their cell membrane inwards to allow the B7 protein and the CD28 receptor to bind each other. -- "People often assume the cell membrane is flat, but it actually looks more like a coastline with lots of coves and bays," said Hui. "We found that local membrane curvatures are actually a rich dimension of T cell auto-signaling, which is paradigm-shifting in a field that assumed this only happened across cells." -- The researchers then confirmed that this auto-stimulation was indeed effective in boosting T cell function and slowing tumor growth in a mouse model of cancer. -- "When a T cell exits a lymph organ and enters a tumor environment, it's like leaving home and going for a long trek in the woods," said Bui. "The same way a hiker brings snacks to sustain them through the trip, the T cells bring their own signal to keep them going. Now the exciting question is, how much farther will they go if we can provide more food?" [] Monoclonal antibody therapy, T cell, Tumor suppressor gene, Renal cell carcinoma, BRCA1, Metastasis, Cancer, Chemotherapy | 2319-E002 |
| 140 | 2319-E032 | E02 | New Probe Advances Cell Function Research | Researchers have used a new cellular probe to discover new information about cellular processes. The probe has been instrumental in uncovering new findings about a variety of cellular mechanisms. | University of Cincinnati | ACS Sensors | Collaborative research at the University of Cincinnati has developed a new probe to better study cells that has already led to new knowledge about certain cellular processes. -- UC's Jiajie Diao, PhD, and Yujie Sun, PhD, are lead authors on new research published May 4 in ACS Sensors. -- Focus on endolysosomes -- The team's research focused on organelles, or specialized structures that perform various jobs inside cells, called endolysosomes. Lysosomes are organelles that act as the "recycling center" of the cell, reusing broken or malfunctioning building blocks for different purposes, and endolysosomes are a subset of lysosomes that begin as a different organelle called an endosome. -- Lysosomes are an important organelle to study because abnormalities can lead to what are called lysosomal storage diseases that cause buildups of toxic substances in cells. Abnormalities in lysosome function are also associated with neurodegenerative diseases and cancer. -- "If lysosomes are not functioning normally, then the cell will accumulate lots of waste, eventually leading to cell death," said Diao, University of Cincinnati Cancer Center member and associate professor in the Department of Cancer Biology in UC's College of Medicine. -- In the process of transitioning from an endosome to a lysosome, these organelles change their pH levels from a neutral environment to an acidic environment. If the environment is not acidic enough, lysosomes cannot do their jobs of clearing and recycling waste properly. -- "We are trying to image this process and trying to track the whole changing process of the endolysosome and trying to figure out in which state and which location these endolysosomes will become abnormal," Diao said. -- New probe -- Diao and Sun's team published research last year on the ECGreen probe that turned a brighter shade of green when the cell environment becomes more acidic. While it was a step forward, Diao said ECGreen still had limitations. [] Digestion, Biochemistry, Mutation, Mitochondrion, Morphogenesis, Inflammation, Carbon dioxide, Gas exchange | 2319-E032 |
| 141 | 2319-E006 | E01 E03 E04 | Rapeseed's Protein Power for Human Consumption | Researchers have made progress in removing bitter substances from rapeseed plants, which could pave the way for a new protein source to support the green transition. Until now, rapeseed has only been used for oil and animal feed due to its bitter taste and unsuitability for human consumption. | University of Copenhagen - Faculty of Science | Nature | Half of plant proteins in the EU come from rapeseed plants. Until now, the plant has only been used for oil and animal feed, as it is both bitter and unsafe for human consumption. In a new study published in Nature, University of Copenhagen researchers have gotten closer to removing the plant's bitter substances, and in doing so, are paving the way for a new protein source to support the green transition. -- Yellow flower carpeted fields are a sure sign of summer. In Denmark, more than 200,000 hectares of rapeseed are now cultivated for use as edible and industrial oils, and as a protein supplement for animal feed -- but not as a direct food source for humans. While the rapeseed plant's high content of bitter defensive substances keep disease and herbivores at bay, they also make the plant inedible for humans. -- Now, a team of scientific researchers from the University of Copenhagen's Department of Plant and Environmental Sciences has identified the proteins that help store the bitter substances in seeds of thale cress, a model plant and close relative of rapeseed. The new research result has just been published in the scientific journal Nature. -- The knowledge can be used to remove these proteins and in doing so, rapreseed's bitter taste, which offers a wealth of opportunity. Indeed, half of the EU's locally-grown plant proteins already come from rapeseed plants. -- "The climate crisis demands that we reduce meat consumption and eat more plants, which is where rapeseed has great potential as a new source of plant protein in the green transition. Our latest research results bring us a critical step closer to making full use of rapeseed," says Professor Barbara Ann Halkier, who led the research. -- Substances in wasabi and mustard are gone -- Rapeseed's bitter defensive substances are called glucosinolates and are best known as the spicy flavors in wasabi and mustard. As a result, the so-called rapeseed cake, which is the remains of the seeds after the oil has been squeezed out, has only been used in limited quantities as feed for pigs and chickens, despite its staggering 30-40 percent protein content. -- The researchers succeeded in removing the bitter defensive substances by identifying the three proteins in the plant responsible for transporting the substances into its seeds. The new knowledge makes it possible to prevent the accumulation of these substances in the seed by removing the proteins by way of a technology called 'transport engineering'. As such, the defensive substances remain in all other parts of the plant, allowing it to continue to defend itself. -- "Our research demonstrates that the connection -- a kind of umbilical cord -- that exists between the seeds and surrounding fruit shell, is a cell factory for the production of glucosinolates which end up in the seeds. After all, plants are well rooted in soil and cannot just walk away when there is danger. They need to produce a multitude of defensive substances to protect themselves from attacks by disease and herbivores. Our discovery has allowed us to find a way to eliminate these bitter substances from the seeds," says Dr. Deyang Xu, lead author of the new study. -- A breakthrough ten years in the making [] Canola, Plant cell, Herbivore, Seed predation, Hydroponics, Herb, Cocoa, Plant defense against being eaten | 2319-E006 |
| 142 | 2319-E039 | E03 E04 | Small Wildlife Surveys Yield Big Results | Small-scale wildlife surveys can provide valuable information about the health of entire ecosystems. These surveys can offer insights into biodiversity, species interactions, and ecosystem functioning. | University of Exeter | Proceedings of the National Academy of Sciences | Small-scale wildlife surveys can reveal the health of entire ecosystems, new research shows. -- Monitoring wildlife is one of the most costly and difficult aspects of conservation, and often depends on long-term observations in individual species. -- But the study reveals a new and effective method. -- It focusses on "interactions" between species, such as insects pollinating flowers or birds feeding on plants. -- The results show that a small snapshot of interactions is a reliable indicator of the health of an entire community of species. Specifically, the study looked at whether these communities are "persistent" or not -- meaning whether all species are fine or if any are declining to extinction. -- The study was carried out by the University of Exeter, McGill University, the University of Toronto, Princeton University and MIT. -- "All communities of plants and animals are supported by an underlying network of interactions between species," said Dr Christopher Kaiser-Bunbury, from the Centre for Ecology and Conservation at Exeter's Penryn Campus in Cornwall. -- "Our study -- which combines theory, statistics and real-world data -- shows that examining a few of these interactions can provide 'big picture' conclusions about ecosystem health. -- "This information is essential for policymakers, scientists and societies, as we try to tackle the global biodiversity crisis." -- When environmental conditions change, interactions between species often change too -- providing an early indicator of wider problems. [] Wildlife gardening, Veterinary medicine, Marine conservation, Nitrogen oxide, Ecosystem, Pesticide poisoning, Fujita scale, Richter magnitude scale | 2319-E039 |
| 143 | 2319-E019 | E01 E03 E04 | Vanishing Glaciers Threaten Alpine Biodiversity | Researchers warn that with glaciers melting at unprecedented rates due to climate change, invertebrates that live in the cold meltwater rivers of the European Alps will face widespread habitat loss. This could lead to many species becoming restricted to colder habitats that will only persist higher in the mountains. | University of Leeds | Nature Ecology & Evolution | With glaciers melting at unprecedented rates due to climate change, invertebrates that live in the cold meltwater rivers of the European Alps will face widespread habitat loss, warn researchers. -- Many of the species are likely to become restricted to cold habitats that will only persist higher in the mountains, and these areas are also likely to see pressures from the skiing and tourism industries or from the development of hydroelectric plants. -- The research study -- led jointly by the University of Leeds and University of Essex -- calls on conservationists to consider new measures to protect aquatic biodiversity. -- Invertebrates -- key role in ecosystems -- The invertebrates, which include stoneflies, midges and flatworms, play a key role in nutrient cycling and organic matter transfer to fish, amphibians, birds and mammals in the wider Alpine ecosystem. -- Using glacier, landscape and biodiversity mapping data collected across the Alps, scientists from across Europe simulated how key invertebrate populations across the mountain range are likely to change between now and 2100 because of climate change. -- As the climate warms, the modelling predicted the invertebrate species would seek out colder conditions in the highest parts of the mountain range. In the future, these colder areas are also likely to be prioritised for skiing or tourism or the development of hydropower plants. -- Lee Brown, Professor of Aquatic Science at the University of Leeds who co-led the research, said: "Conservationists need to be thinking about how protected area designations must evolve to take into account the effects of climate change. -- "It may be that some species will have to be moved to refuge areas if we want to safeguard their survival as many of them are not strong fliers so they cannot disperse easily through the mountains." -- Alpine climate is changing rapidly [] Mountain, Water resources, Invasive species, Geology of the Alps, Global warming, Bamboo plant, Polar Bear, Winter storm | 2319-E019 |
| 144 | 2319-E029 | E01 E03 | Bird Size Predicts Climate Change Impacts | As the world continues to warm, bird populations in the Americas are undergoing changes in body shape and wing size. The smallest bird species are experiencing the most significant changes, and this could have profound implications for their survival. | University of Michigan | Proceedings of the National Academy of Sciences | Birds across the Americas are getting smaller and longer-winged as the world warms, and the smallest-bodied species are changing the fastest. -- That's the main finding of a new University of Michigan-led study scheduled for online publication May 8 in the journal Proceedings of the National Academy of Sciences. -- The study combines data from two previously published papers that measured body-size and wing-length changes in a total of more than 86,000 bird specimens over four decades in North and South America. One study examined migrating birds killed after colliding with buildings in Chicago; the other looked at nonmigrating birds netted in the Amazon. -- Though the two datasets are nonoverlapping in both species composition and geography, and the data were collected independently using different methods, the birds in both studies displayed similarly widespread declines in body size with concurrent increases in wing length. -- Now, a new analysis of the combined data has revealed an even more striking pattern: In both studies, smaller bird species declined proportionately faster in body size and increased proportionately faster in wing length. -- "The relationships between body size and rates of change are remarkably consistent across both datasets. However, the biological mechanism underlying the observed link between body size and rates of morphological change requires further investigation," said U-M ornithologist Benjamin Winger, one of the study's two senior authors, an assistant professor of ecology and evolutionary biology, and an assistant curator at the Museum of Zoology. -- Both the Chicago and Amazonian studies attributed the reductions in species body size to increasing temperatures over the past 40 years, suggesting that body size may be an important determinant of species responses to climate change. -- Even so, exactly why smaller-bodied species are changing faster remains an open question, according to the researchers. -- It could be that smaller-bodied birds are adapting more quickly to evolutionary pressures. But the available data did not allow the U-M-led team to test whether the observed size shifts represent rapid evolutionary changes in response to natural selection. -- "If natural selection plays a role in the patterns we observed, our results suggest that smaller bird species might be evolving faster because they experience stronger selection, are more responsive to selection, or both," said co-senior author Brian Weeks, an evolutionary ecologist at the U-M School for Environment and Sustainability. [] Egg (biology), Dove, Flamingo, Extinction, Leopard, Owl, Dinosaur, Primate | 2319-E029 |
| 145 | 2319-E031 | E01 E03 E04 | Uniform Prey Create Spider-Eat-Spider Society | A new study suggests that limiting a spider's food sources can lead to a complicated food web in which wolf spiders of different species may resort to cannibalism. The research provides insights into the ecological dynamics of predator-prey relationships. | University of Nebraska-Lincoln | Journal of Animal Ecology | A limited menu of prey may weave a tangled food web by emboldening wolf spiders of multiple species to dine on each other and even cannibalize their own, says a study from the University of Nebraska-Lincoln. -- Ecologists have long known that predators with otherwise-similar diets can coexist by effectively divvying up the food sources of a community to ease competition and, ideally, leave enough prey for everyone. But analyses of wolf spider species in Nebraska suggest that when the diversity of their mutual prey is lacking, the eight-legged predators might instead maintain an ecological equilibrium, in part, by eating one another. -- A decline in the variety of prey should spell bad news for weaker predators, which are then put into more direct competition with their stronger counterparts, said Stella Uiterwaal, who led the study while earning her doctorate at Nebraska. Predators that do manage to at least occasionally kill and eat their more competitive peers, though, could benefit in a couple of ways that collectively act as an "equalizing mechanism," she said. -- "Some of your diet is now coming from that other predator, instead of the shared prey that you're competing for," said Uiterwaal, now a postdoctoral researcher at Washington University in St. Louis. "And you're also reducing the population size of that better predator, so you have fewer of them to compete with." -- The study originated from what Uiterwaal observed while studying and later teaching at Cedar Point Biological Station, a lake-adjacent field site in southwest Nebraska. It was there that she and some colleagues, including doctoral adviser John DeLong, realized that the wealth of local wolf spider species seemed to be defying an ecological principle by occupying more or less the same niche of the same habitat. -- "We noticed that there are so many different wolf spider species that all seem to be doing the same thing," Uiterwaal said. "And there's this classic ecological idea that species can't be doing the exact same thing. If that happens, they won't be able to persist in the environment for very long." -- So the researchers spent two summers collecting specimens of eight wolf spider species and their potential prey. Wanting to get as accurate a count of that prey as possible, Uiterwaal took to plopping hollow wooden boxes onto unsuspecting plots of earth, then using a customized vacuum to suck up every ground-bound and flying insect within. Many of the captured critters also appeared on the wolf spider menu: flies, grasshoppers, crickets, butterflies, moths, aphids and, yes, other spiders. -- "You name it, and they'll eat it," Uiterwaal said. "We've even seen spiders out there eating toads." -- Still, cataloging the actual diets of 605 wolf spiders would require more sophisticated techniques. One of those techniques involved analyzing the DNA of the spiders' digested food in search of barcodes: DNA sequences unique to each type of prey the spiders consumed. Uiterwaal also applied a mathematical method -- one she developed -- that helped the team ascertain how much of each prey a spider had consumed. -- Counter to the team's expectations, the diet of any one wolf spider species mostly resembled the others. [] Tarantula, Spider, Gray Wolf, Hobo spider, Snake, Widow spider, Evolution of the eye, Red Wolf | 2319-E031 |
| 146 | 2319-E035 | E01 E04 | Bacteria-Killing Material for Hospital Superbugs | A new antimicrobial coating material has been developed using a common disinfectant and antiseptic. This coating effectively kills bacteria and viruses, including MRSA and SARS-COV-2. | University of Nottingham | Nano Select | Researchers have used a common disinfectant and antiseptic to create a new antimicrobial coating material that effectively kills bacteria and viruses, including MRSA and SARS-COV-2. -- Scientists at the University of Nottingham's School of Pharmacy took chlorhexidine, often used by dentists to treat mouth infections and for pre-surgical cleaning, and used it to coat the polymer, acrylonitrile butadiene styrene (ABS). The new study published in Nano Select shows that this new material was found to be effective in killing the microbes responsible for a range of infections and illnesses and could be used as an effective antimicrobial coating on a range of plastic products. -- Plastics are widely used in medical settings, from intravenous bags and implantable devices to hospital beds and toilet seats. Some microbial species can survive in a hospital setting despite enhanced cleaning regimes, leading to an increased risk of patients getting infections whilst in hospital which then need antibiotic treatment. These microorganisms can survive and remain infectious on abiotic surfaces, including plastic surfaces, for extended periods, sometimes up to several months. -- Dr Felicity de Cogan, Assistant Professor in Pharmaceutical Science of Biological Medicines led this study, she said: "As plastic is such a widely used material that we know can harbour infectious microorganisms we wanted to investigate a way to use this material to destroy the bacteria. We achieved this by bonding a disinfectant with the polymer to create a new coating material and discovered not only does it act very quickly, killing bacteria within 30 minutes, it also doesn't spread into the environment or leach from the surface when touched. Making plastic items using this material could really help tackle the issue of antibiotic resistance and reduce hospital acquired infections." -- The researchers used a special imaging technique called Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS) to examine the material at molecular level. This revealed the material was antimicrobial and rapidly killed microbes and after 45 minutes the surfaces were still clear of these microbes. It was also effective against SARS-COV-2, with no viable virions found after 30 minutes. Additionally, the surfaces were also effective in killing chlorhexidine-resistant strains of bacteria. -- The COVID-19 pandemic has drawn increased attention to hospital-acquired infections, as it has been estimated that 20% of all patients hospitalized with COVID-19 contracted the virus while already in hospital. It has been estimated that in 2016/17, 4.7% of adult hospital inpatients contracted an infection whilst in hospital, with 22,800 patients dying due to these infections despite these deaths being preventable. The most common pathogens that cause hospital-acquired infections are Escherichia coli, Staphylococcus aureus, and Clostridium difficile. Outbreaks of infection in the clinic are frequently caused by strains resistant to antimicrobial drugs. -- Dr de Cogan continues: "Research has shown that contaminated surfaces, including plastic surfaces, can act as a reservoir of antimicrobial resistance genes, encouraging the spread of antimicrobial resistance across bacterial species through horizontal gene transfer despite deep cleaning practices. It is paramount that new technologies are developed to prevent the spread of pathogenic microorganisms to vulnerable patients and address the ever-increasing threat of antimicrobial resistance. -- "This research offers an effective way to do this and the material could be added to plastic materials during manufacture, it could also potentially be used as a spray." [] Severe acute respiratory syndrome, Virus, Antibiotic resistance, Water purification, Honey, Human parainfluenza viruses, Mutation, Immune system | 2319-E035 |
| 147 | 2319-E009 | E01 E03 E04 | Archaea in Warming Climate Become Less Diverse | A long-term experiment has shown that experimental warming of a tallgrass prairie ecosystem significantly altered the community structure of soil archaea and reduced their taxonomic and phylogenetic diversity. | University of Oklahoma | Nature Climate Change | Led by Jizhong Zhou, Ph.D., the director of the Institute for Environmental Genomics at the University of Oklahoma, an international research team conducted a long term experiment that found that climate warming reduced the diversity of and significantly altered the community structure of soil archaea. Their findings are published in the journal Nature Climate Change. -- At the microbiological level, life can be described as belonging to one of three kingdoms -- how species are described in relation to one another. Eukarya contains complex organisms like animals and plants and microorganisms such as fungi. The other two categories, bacteria and archaea, are comprised only of microorganisms. Archaea are prevalent in a range of environments, from some of the most hostile like volcanoes and permafrost. However, archaea are also common in the human microbiome and as an important part of soil ecology. -- "As temperature is a major driver of biological processes, climate warming will impact various ecological communities," Zhou said. "Based on long-term time-series data, our previous studies revealed that experimental warming leads to the divergent succession of soil bacterial and fungal communities, accelerates microbial temporal scaling, reduces the biodiversity of soil bacteria, fungi and protists, but increases bacterial network complexity and stability. However, how climate warming affects the temporal succession of the archaeal community remains elusive. Archaea are ubiquitously present in soil and are vital to soil functions, e.g., nitrification and methanogenesis." -- Using a long-term multifactor experimental field site at OU's Kessler Atmospheric and Ecological Field Station, the researchers showed that experimental warming of a tallgrass prairie ecosystem significantly altered the community structure of soil archaea and reduced their taxonomic and phylogenetic diversity. In contrast to the researchers' previous observations in bacteria and fungi, their finds show that climate warming leads to convergent succession of the soil archaeal community, suggesting archaeal community structures would become more predictable in a warmer world. [] Biodiversity, Prairie Restoration, Soil science, Hydroponics, Climate change mitigation, Organic farming, Soil life, Ecosystem | 2319-E009 |
| 148 | 2319-E040 | E05 | Super-Resolution Imaging Technology | Researchers have developed a super-resolution imaging platform technology to improve understanding of how nanoparticles interact within cells. This technology can offer new insights into various cellular mechanisms and has broad applications in various fields of research. | University of Oklahoma | ACS Nano | Led by Stefan Wilhelm, Ph.D., assistant professor in the Stephenson School of Biomedical Engineering at the University of Oklahoma, a team of researchers from the Gallogly College of Engineering at OU, OU Health Sciences Center and Yale University recently published an article in ACS Nano that describes their development of a super-resolution imaging platform technology to improve understanding of how nanoparticles interact within cells. -- As technology-driven capabilities in engineering and healthcare are ever-increasing, scientists and engineers are developing new technologies to advance the future of health. One such area, nanomedicine, explores the use of nanoparticles for drug delivery in the body to fight against infectious diseases or cancer. The assessment of these nanomedicines in cells, tissues and organs is often performed by optical imaging, which can have a limited quality of imaging resolution. New imaging technologies are needed to see nanoparticles in their 3-D ultrastructural context within biological tissues. -- "To see nanomedicines in biological samples, researchers either use electron microscopy, which provides excellent spatial resolution but lacks 3-D imaging capabilities, or optical microscopy, which achieves excellent 3-D imaging, but exhibits relatively low spatial resolution," Wilhelm said. "We demonstrate that we can perform 3-D imaging of biological samples with electron microscopy-like resolution. This technique, called super-resolution imaging, allows us to see nanomedicines inside individual cells. Using this new super-resolution imaging method, we can now start to track and monitor nanoparticles inside cells, which is a prerequisite for designing nanomedicines that are safer and more efficient in reaching certain areas within cells." -- The researchers applied a 3-D super-resolution imaging technique known as expansion microscopy which involves embedding cells within swellable hydrogels. Like water-absorbing materials used in diapers, the hydrogel materials physically expand up to 20-fold their original size upon contact with water. -- "This expansion enables the imaging of cells with a lateral resolution of approximately 10 nanometers using a conventional optical microscope," Wilhelm said. "We combined this method with an approach to image metallic nanoparticles within cells. Our approach exploits the inherent ability of metallic nanoparticles to scatter light. We used the scattered light to image and quantify nanoparticles inside cells without the need for any additional nanoparticle labels." -- The authors suggest their super-resolution imaging platform technology could be used to improve the engineering of safer and more effective nanomedicines to advance the translation of these technologies into the clinic. [] Nanoparticle, Transmission electron microscopy, Stem cell, Electron microscope, Conflict resolution, Battery (electricity), Tissue engineering, Mammalian embryogenesis | 2319-E040 |
| 149 | 2319-E021 | E03 | Jurassic Seas' Giants Twice Killer Whale Size | Palaeontologists have published a paper on a Jurassic species potentially reaching a whopping 14.4 meters, based on a chance discovery in an Oxfordshire museum, potentially settling debates over the size of Jurassic animals. | University of Portsmouth | Proceedings of the Geologists' Association | Over 20 years ago, the BBC's Walking with Dinosaurs TV documentary series showed a 25-metre long Liopleurodon. This sparked heated debates over the size of this pliosaur as it was thought to have been wildly overestimated and more likely to have only reached an adult size of just over six metres long. -- The speculation was set to continue, but now a chance discovery in an Oxfordshire museum has led to University of Portsmouth palaeontologists publishing a paper on a similar species potentially reaching a whopping 14.4 metres -- twice the size of a killer whale. -- Professor David Martill from the University of Portsmouth's School of the Environment, Geography and Geosciences, said: "I was a consultant for the BBC's pilot programme 'Cruel Sea' and I hold my hands up -- I got the size of Liopleurodon horrendously wrong. I based my calculations on some fragmentary material which suggested a Liopleurodon could grow to a length of 25 metres, but the evidence was scant and it caused a lot of controversy at the time. -- "The size estimate on the BBC back in 1999 was overdone, but now we have some evidence that is much more reliable after a serendipitous discovery of four enormous vertebrate." -- Professor Martill's co-author, Megan Jacobs, was photographing an ichthyosaur skeleton at Abingdon County Hall Museum, while Dave looked through drawers of fossils. He found a large vertebra and was thrilled to discover the curator had three more of them in storage. -- The vertebrae are clearly identifiable as being closely related to a Pliosaurus species or similar animal. Pliosaurs were like plesiosaurs, but with a bigger elongated head, similar to a crocodile, and a shorter neck. They had four flippers, which acted as powerful paddles to propel them through water and a relatively short tail. -- After conducting topographic scans, Professor Martill and colleagues calculated this Late Jurassic marine reptile could have grown to between 9.8 and 14.4 metres long. -- He said: "We know these pliosaurs were very fearsome animals swimming in the seas that covered Oxfordshire 145-152 million years ago. They had a massive skull with huge protruding teeth like daggers -- as big, if not bigger than a T. rex, and certainly more powerful. -- "They were at the top of the marine food chain and probably preyed on ichthyosaurs, long-necked plesiosaurs and maybe even smaller marine crocodiles, simply by biting them in half and taking chunks off them. We know they were massacring smaller marine reptiles because you can see bite marks in ichthyosaur bones in examples on display in The Etches Collection in Dorset." -- The vertebrae were originally discovered during temporary excavations at Warren Farm in the River Thames Valley in Oxfordshire and come from the Kimmeridge Clay Formation. This deposit is Late Jurassic in age, around 152 million years old. [] Jurassic, Cretaceous, Gray Whale, Colossal Squid, Brachiosaurus, Fin Whale, Mesozoic, Sperm Whale | 2319-E021 |
| 150 | 2319-E036 | E03 | Kangaroo Island Ants Play Dead to Avoid Predators | A new study has found that a species of ants on Kangaroo Island has a unique ability to play dead. Researchers believe that this behavior is a recorded world first. | University of South Australia | Australian Journal of Zoology | They're well known for their industrious work, but now a species of ant on Kangaroo Island is also showing that it is skilled at 'playing dead', a behaviour that University of South Australia researchers believe is a recorded world first. -- Accidentally discovered as researchers were checking pygmy-possum and bat nest boxes on Kangaroo Island, a colony of Polyrhachis femorata ants appeared to be dead… until one moved. -- Researchers believe the ants were 'playing dead' as a defensive strategy to avoid potential danger. -- Published by CSIRO, this is the first time that a whole colony of ants has been recorded feigning death, and the first record of the Polyrhachis femorata ant species for South Australia. -- Wildlife ecologist, UniSA's Associate Professor S. 'Topa' Petit, says she was surprised to discover a colony of what appeared to be dead ants in one of the nest boxes. -- "The mimicry was perfect," Assoc Professor Petit says. "When we opened the box, we saw all these dead ants…and then one moved slightly. -- "This sort of defensive immobility is known among only a few ant species -- in individuals or specific casts -- but we don't know of other instances when it's been observed for entire colonies. -- "In some of the boxes containing colonies of Polyrhachis femorata, some individuals took a while to stop moving, and others didn't stop. The triggers for the behaviour are difficult to understand." -- Assoc Prof Petit says that nest boxes may present an opportunity to study the ants' death-feigning behaviours, which are of great interest to many behavioural ecologists investigating a diversity of animal species. -- The discovery was made during the Kangaroo Island Nest Box Project, where 901 box cavities have been monitored across 13 diverse properties as part of wildlife recovery efforts following the devastating 2020 bushfires. [] Dog intelligence, Krakatoa, Dead zone (ecology), Fire ant, Larsen Ice Shelf, 1928 Okeechobee Hurricane, Howler monkey, Botulinum toxin (cosmetic treatment) | 2319-E036 |
| 151 | 2319-E038 | E01 E03 E04 | Neanderthal Lifestyle Clues from Tooth Enamel | A recent study has provided insight into the hunting habits and diets of Neanderthals and other humans living in Western Europe. | University of Southampton | Proceedings of the National Academy of Sciences | A study by an international team of researchers, led by the University of Southampton, has given an intriguing glimpse of the hunting habits and diets of Neanderthals and other humans living in western Europe. -- The scientists examined chemical properties locked inside tooth enamel to piece together how pre-historic people lived off the land around the Almonda Cave system, near Torres Novas in central Portugal almost 100 thousand years ago. -- Their findings, published in the journal PNAS, show Neanderthals in the region were hunting fairly large animals across wide tracts of land, whereas humans living in the same location tens of thousands of years later survived on smaller creatures in an area half the size. -- Strontium isotopes in rocks gradually change over millions of years because of radioactive processes. This means they vary from place to place depending on the age of the underlying geology. As rocks weather, the isotopic 'fingerprints' are passed into plants via sediments, and make their way along the food chain -- eventually passing into tooth enamel. -- In this study, archaeologists used a technique which laser samples enamel and makes thousands of individual strontium isotope measurements along the growth of a tooth crown. Samples were taken from two Neanderthals, dating back about 95,000 years, and from a more recent human who lived about 13,000 years ago, during the Magdalenian period. -- The scientists also looked at isotopes in the tooth enamel of animals found in the cave system. Alongside strontium, they measured oxygen isotopes, which vary seasonally from summer to winter. This enabled them to establish not only where the animals ranged across the landscape, but in which seasons they were available for hunting. -- The team showed that the Neanderthals, who were targeting large animals, could have hunted wild goat in the summer, whereas horses, red deer and an extinct form of rhinoceros were available all year round within about 30km of the cave. The Magdalenian individual showed a different pattern of subsistence, with seasonal movement of about 20km from the Almonda caves to the banks of the Tagus River, and a diet which included rabbits, red deer, wild goat and freshwater fish. -- The researchers approximated the territory of the two different human groups, revealing contrasting results. The Neanderthals obtained their food over approximately 600 km2, whereas the Magdalenian individuals occupied a much smaller territory of about 300 km2. -- Lead author, Dr Bethan Linscott who conducted the research while at the University of Southampton and who now works at the University of Oxford said: "Tooth enamel forms incrementally, and so represents a time series that records the geological origin of the food an individual ate. -- "Using laser ablation, we can measure the variation of strontium isotopes over the two or three years it takes for the enamel to form. By comparing the strontium isotopes in the teeth with sediments collected at different locations in the region, we were able to map the movements of the Neanderthals and the Magdalenian individual. The geology around the Almonda caves is highly variable, making it possible to spot movement of just a few kms." [] Neandertal interaction with Cro-Magnons, Neanderthal, Homo heidelbergensis, Gorilla, Ancient Rome, Year Without a Summer, Chernobyl disaster, Dodo and related birds | 2319-E038 |
| 152 | 2319-E011 | E03 | Evolution of Honey Bee Brains | Researchers have proposed a new model for the evolution of higher brain functions and behaviors in the Hymenoptera order of insects. This research could help us better understand the evolution of some of our own higher brain functions and behaviors in the future. | University of Tokyo | Science Advances | Researchers have proposed a new model for the evolution of higher brain functions and behaviors in the Hymenoptera order of insects. The team compared the Kenyon cells, a type of neuronal cell, in the mushroom bodies (a part of the insect brain involved in learning, memory and sensory integration) of "primitive" sawflies and sophisticated honey bees. They found that three diverse, specialized Kenyon cell subtypes in honey bee brains appear to have evolved from a single, multifunctional Kenyon cell-subtype ancestor. In the future, this research could help us better understand the evolution of some of our own higher brain functions and behaviors. -- Are you "busy as a bee," a "social butterfly" or a "fly on the wall"? There are many ways we compare our behavior to that of insects, and as it turns out there may be more to it than just fun idioms. Studying insects could help us understand not only how their behavior has evolved, but also the behavior of highly evolved animals, including ourselves. Mammalian brains are big and complex, so it is difficult to identify which behaviors and neural and genetic changes have co-developed over time. By comparison, insect brains are much smaller and simpler, making them useful models for study. -- "In 2017, we reported that the complexity of Kenyon cell (KC) subtypes in mushroom bodies in insect brains increases with the behavioral diversification in Hymenoptera (a large and varied order of insects)" explained Professor Takeo Kubo from the Graduate School of Science at the University of Tokyo and co-author of the current study. "In other words, the more KC subtypes an insect has, the more complex its brain and the behaviors it may exhibit. But we didn't know how these different subtypes evolved. That was the stimulus for this new study." -- The team from the University of Tokyo and Japan's National Agriculture and Food Research Organization (NARO) chose two Hymenoptera species as representatives for different behaviors: the solitary turnip sawfly (which has a single KC subtype) and the sophisticated, social honey bee (which has three KC subtypes). As the sawfly has a more "primitive" brain, it is thought to contain some ancestral properties of the honey bee brain. To uncover the potential evolutionary pathways between them, the researchers used transcriptome analysis to identify the gene expression profiles (the genetic activity) of the various KC subtypes and speculate their functions. -- "I was surprised that each of the three KC subtypes in the honey bee showed comparable similarity to the single KC type in the sawfly," said Assistant Professor Hiroki Kohno, co-author from the Graduate School of Science. "Based on our initial comparative analysis of several genes, we had previously supposed that additional KC subtypes had been added one by one. However, they appear to have been separated from a multifunctional ancestral type, through functional segregation and specialization." As the number of KC subtypes increased, each subtype almost equally inherited some distinct properties from an ancestral KC. These then modified in different ways, resulting in their varied present-day functions. -- The researchers wanted a specific behavioral example of how ancestral KC functions are present in both the sawfly and the honey bee. So, they trained sawflies to engage in a common honey bee behavior test, where they learn to associate an odor stimulus with a reward. Although challenging at first, the team was eventually able to engage the sawflies in the memory task. The researchers then manipulated a gene called CaMKII in sawfly larvae, which in honey bees is associated with forming long-term memory, a KC function. When the larvae became adults, their long-term memory was impaired, indicating that the gene plays a similar role in both sawflies and honey bees. Although CaMKII was expressed (i.e., was active) across the entire single KC subtype in sawflies, in honey bees, it was preferentially expressed in only one KC subtype. This suggests that the role of CaMKII in long-term memory was passed down to the specific KC subtype in the honey bee. -- Despite differences in the size and complexity of insect and mammalian brains, there are commonalities in terms of function and the basic architecture of the nervous system. That is why the model proposed in this study for the evolution and diversification of KC subtypes may help towards better understanding the evolution of our own behavior. Next, the team is interested in studying KC types acquired in parallel with social behaviors, such as the honey bee's "waggle dance." -- "We would like to clarify whether the model presented here is applicable to the evolution of other behaviors," said Takayoshi Kuwabara, doctoral student and lead author from the Graduate School of Science. "There are many mysteries about the neural basis that controls social behavior, whether in insects, animals or humans. How it has evolved still remains largely unknown. I believe that this study is a pioneering work in this field." [] Brain, Cell (biology), Stem cell, Honeybee, Organelle, Bee sting, Adult stem cell, Neocortex (brain) | 2319-E011 |
| 153 | 2319-E022 | E01 E02 E03 | Dark Clouds on the Horizon | Researchers have quantified the refractive index of black carbon to the most accurate degree yet, which might impact climate models as black carbon is especially problematic due to its ability to absorb heat and impede the heat reflection capabilities of surfaces such as snow. | University of Tokyo | Aerosol Science and Technology | Our industrialized society releases many and various pollutants into the world. Combustion in particular produces aerosol mass including black carbon. Although this only accounts for a few percent of aerosol particles, black carbon is especially problematic due to its ability to absorb heat and impede the heat reflection capabilities of surfaces such as snow. So, it's essential to know how black carbon interacts with sunlight. Researchers have quantified the refractive index of black carbon to the most accurate degree yet which might impact climate models. -- There are many factors driving climate change; some are very familiar, such as carbon dioxide emissions from burning fossil fuels, sulfur dioxide from cement manufacture or methane emissions from animal agriculture. Black carbon aerosol particles, also from combustion, are less covered in the news but are particularly important. Essentially soot, black carbon is very good at absorbing heat from sunlight and storing it, adding to atmospheric heat. At the same time, given dark colors are less effective at reflecting light and therefore heat, as black carbon covers lighter surfaces including snow, it reduces the potential of those surfaces to reflect heat back into space. -- "Understanding the interaction between black carbon and sunlight is of fundamental importance in climate research," said Assistant Professor Nobuhiro Moteki from the Department of Earth and Planetary Science at the University of Tokyo. "The most critical property of black carbon in this regard is its refractive index, basically how it redirects and disperses incoming light rays. However, existing measurements of black carbon's refractive index were inaccurate. My team and I undertook detailed experiments to improve this. With our improved measurements, we now estimate that current climate models may be underestimating the absorption of solar radiation due to black carbon by a significant 16%." -- Previous measurements of the optical properties of black carbon were often confounded by factors such as lack of pure samples, or difficulties in measuring light interactions with particles of differing complex shapes. Moteki and his team improved this situation by capturing the black carbon particles in water, then isolating them with sulfates or other water-soluble chemicals. By isolating the particles, the team was better able to shine light on them and analyze the way they scatter, which gave researchers the data to calculate the value of refractive index. -- "We measured the amplitude, or strength, and phase, or step, of the light scattered from black carbon samples isolated in water," said Moteki. "This allowed us to calculate what is known as the complex refractive index of black carbon. Complex because rather than being a single number, it's a value that contains two parts, one of which is 'imaginary' (concerned with absorption), though its impact is very, very real. Such complex numbers with imaginary components are actually very common in the field of optical science and beyond." -- As the new optical measurements of black carbon imply that current climate models are underestimating its contribution to atmospheric warming, the team hopes that other climate researchers and policymakers can make use of their findings. The method developed by the team to ascertain the complex refractive index of particles can be applied to materials other than black carbon. This allows for the optical identification of unknown particles in the atmosphere, ocean or ice cores, and the evaluation of optical properties of powdered materials, not just those related to the ongoing problem of climate change. [] Carbon monoxide, Carbon dioxide sink, Carbon dioxide, Smoke, Carbon cycle, Forest, Fossil fuel, Global climate model | 2319-E022 |
| 154 | 2319-E010 | E03 E04 | Single Approach to Wild Horses | According to researchers, contrasting societal views have created an approach that makes current U.S. government programs incapable of succeeding in managing horses on the range as wildlife, livestock, and pets. | University of Wyoming | BioScience | The U.S. federal government's management of wild horses is doomed to fail without fundamental changes in policy and the law, according to a new paper led by researchers at the University of Wyoming and Oklahoma State University. -- Because contrasting societal views have created an approach that simultaneously manages horses on the range as wildlife, livestock and pets, current government programs are incapable of succeeding, the researchers argue in the article that appears in the journal BioScience. -- "For the federal government to sustain healthy populations, ecosystem health and fiscal responsibility, lawmakers must properly define how feral equids should be labeled," the scientists wrote. "Each label (wild, livestock, pet) has validity, and management plans can be implemented to optimize equid populations with other land uses. Furthermore, providing a clear definition of feral equids will determine the legal tools that can be applied for their management." -- The lead author of the paper is Jacob Hennig, a former UW Ph.D. student who is now a postdoctoral researcher at Oklahoma State. Hennig's advisers at UW -- Professor Jeff Beck and Associate Professor Derek Scasta, both in the Department of Ecosystem Science and Management -- are co-authors of the paper. So are Oklahoma State Professor Sam Fuhlendorf and Assistant Professor Courtney Duchardt, who is a former UW Ph.D. student; Colorado State University research scientist Saeideh Esmaeili, also a former UW Ph.D. student; and Tolani Francisco, of Native Healing LLC in New Mexico. -- The researchers note that, while the fossil record shows there were horses in North America previously, they went extinct about 10,000 years ago. -- "The equids currently inhabiting North America did not coevolve there; they are descendants of livestock that underwent millennia of domestication and artificial selection," the paper says. "Most large predators that would help limit their population growth went extinct at the end of the Pleistocene (epoch), and the Anthropocene (current epoch) has led to further predator reductions." -- Because wild horses have no natural predators, cannot be legally hunted under federal law and are no longer slaughtered as livestock in the United States, their numbers on the range have more than doubled in the last decade, the researchers say. They also note that horses removed from the range by the Bureau of Land Management (BLM) and held in government facilities and private lands have grown in number by 33 percent during that time, with the BLM spending over $550 million since 2013 supporting the captive animals. -- "The BLM has increased the number of individuals removed from the wild in each of the past four years, leading to decreases in the on-range population," the paper acknowledges. "However, the total on-range population is still approximately 50,000 individuals above the maximum (appropriate management level), and the recent moderate decrease in on-range individuals is directly correlated with an increase in the off-range population and subsequent expenditures." -- Removing wild horses from Western rangelands and placing them in long-term holding is not a solution, the researchers say. Doing so "simply exports the issue elsewhere -- including the imperiled tallgrass prairie ecosystem -- with unknown ecological effects," they wrote, noting that there are now about 23,500 wild horses on private lands in Oklahoma, five times more than the number on open range in Wyoming. -- Additionally, the paper contends that wild horses have a comparatively large impact on the range, as they consume more forage and water than ruminants such as cattle, per capita. [] Miniature horse, Wildlife gardening, Palomino horse, Livestock, Veterinary medicine, Donkey, Pesticide poisoning, Icelandic horse | 2319-E010 |
| 155 | 2319-E027 | E01 E02 | CO2 Increases' Climate Change Signal | New research has uncovered unequivocal evidence that human activities have left a distinctive mark on climate change. The study presents specific signals from various human actions that have altered the temperature structure of the Earth's atmosphere. | Woods Hole Oceanographic Institution | Proceedings of the National Academy of Sciences | New research provides clear evidence of a human "fingerprint" on climate change and shows that specific signals from human activities have altered the temperature structure of Earth's atmosphere. -- Differences between tropospheric and lower stratospheric temperature trends have long been recognized as a fingerprint of human effects on climate. This fingerprint, however, neglected information from the mid to upper stratosphere, 25 to 50 kilometers above the Earth's surface. -- "Including this information improves the detectability of a human fingerprint by a factor of five. Enhanced detectability occurs because the mid to upper stratosphere has a large cooling signal from human-caused CO2 increases, small noise levels of natural internal variability, and differing signal and noise patterns," according to the journal article, "Exceptional stratospheric contribution to human fingerprints on atmospheric temperature," published in the Proceedings of the National Academy of Sciences (PNAS). Noise in the troposphere can include day-to-day weather, interannual variability arising from El Niños and La Niñas, and longer-term natural fluctuations in climate. In the upper stratosphere, the noise of variability is smaller, and the human-caused climate change signal is larger, so the signal can be much more easily distinguished. -- "Extending fingerprinting to the upper stratosphere with long temperature records and improved climate models means that it is now virtually impossible for natural causes to explain satellite-measured trends in the thermal structure of the Earth's atmosphere," the paper states. -- "This is the clearest evidence there is of a human-caused climate change signal associated with CO2 increases," according to lead author Benjamin Santer, an adjunct scientist in the Physical Oceanography Department at the Woods Hole Oceanographic Institute (WHOI) in Massachusetts. -- "This research undercuts and rebuts claims that recent atmospheric and surface temperature changes are natural, whether due to the Sun or due to internal cycles in the climate system. A natural explanation is virtually impossible in terms of what we are looking at here: changes in the temperature structure of the atmosphere," added Santer, who has worked on climate fingerprinting for more than 30 years. "This research puts to rest incorrect claims that we don't need to treat climate change seriously because it is all natural." -- The research was motivated by earlier work by Suki Manabe and Richard Wetherald, who in 1967 used a simple climate model to study how CO2 from fossil fuel burning might change atmospheric temperature. Their modeling found a very distinctive feature: an increase in CO2 levels led to more trapping of heat in the troposphere (the lowest layer of Earth's atmosphere) and less heat escaping higher up into the stratosphere (the layer above the troposphere), thus warming the troposphere and cooling the stratosphere. This prediction of tropospheric warming and stratospheric cooling in response to increasing CO2 has been confirmed many times by more complex models and verified by comparing model results with global-mean atmospheric temperature observations from weather balloons and satellites. -- Although these earlier studies considered global-mean temperature changes in the middle and upper stratosphere, roughly 25 to 50 kilometers above Earth's surface, they did not look at detailed patterns of climate change in this layer. This region can be better studied now because of improved simulations and satellite data. The new research is the first to search for human-caused climate change patterns -- also called "fingerprints" -- in the middle and upper stratosphere. -- "The human fingerprints in temperature changes in the mid to upper stratosphere due to CO2 increases are truly exceptional because they are so large and so different from temperature changes there due to internal variability and natural external forcing. These unique fingerprints make it possible to detect the human impact on climate change due to CO2 in a short period of time (~10 -- 15 years) with high confidence," stated co-author Qiang Fu, a professor in the Department of Atmospheric Sciences at the University of Washington. -- "The world has been reeling under climate change, so being as confident as possible of the role of carbon dioxide is critical," said co-author Susan Solomon, Martin Professor of Environmental Studies at the Massachusetts Institute of Technology. "The fact that observations show not only a warming troposphere but also a strongly cooling upper stratosphere is unique tell-tale evidence that nails the dominant role of carbon dioxide in climate change and greatly increases confidence." [] Attribution of recent climate change, Consensus of scientists regarding global warming, Effects of global warming, Temperature record of the past 1000 years, Global climate model, Global warming, Global warming controversy, Water resources | 2319-E027 |
| 156 | 2319-E030 | E01 E02 E03 | Freshwater Release Precursor | The Beaufort Gyre, which is the largest freshwater reservoir in the Arctic Ocean and the dominant circulation of the Canada Basin, has shown signs of stabilization. For the first time, observational evidence has been presented to demonstrate this phenomenon. | Woods Hole Oceanographic Institution | Nature Geoscience | A new study provides the first observational evidence of the stabilization of the anti-cyclonic Beaufort Gyre, which is the dominant circulation of the Canada Basin and the largest freshwater reservoir in the Arctic Ocean. -- The study uses a newly extended record of "dynamic ocean topography" satellite data from 2011-2019 provided by two of the co-authors, along with an extensive hydrographic dataset from 2003-2019, to quantify the changing sea surface height of the gyre in recent years. -- Previous observations and modeling that relied on earlier dynamic ocean topography data up to 2014 have documented that the gyre has strengthened and increased its freshwater content by 40% compared with 1970s climatology. Stabilization of the gyre could be a precursor of a huge freshwater release, which could have significant ramifications including impacting the Atlantic Meridional Overturning Circulation (AMOC), a key component of global climate. -- The Beaufort Gyre "has transitioned to a quasi-stable state in which the increase in sea surface height of the gyre has slowed and the freshwater content has plateaued. In addition, the cold halocline layer, which isolates the warm/salty Atlantic water at depth, has thinned significantly due to less input of cold and salty water stemming from the Pacific Ocean and the Chukchi Sea shelf, together with greater entrainment of lighter water from the eastern Beaufort Sea. This recent transition of the Beaufort Gyre is associated with a southeastward shift in its location as a result of variation in the regional wind forcing," according to the journal article "Recent state transition of the Arctic Ocean's Beaufort Gyre," published in Nature Geoscience. -- "Our results imply that continued thinning of the cold halocline layer could modulate the present stable state, allowing for a freshwater release," the article states. "This in turn could freshen the subpolar North Atlantic, impacting the AMOC." -- Because there could be many potential local and remote impacts of the changing gyre on the hydrographic structure, physical processes, and ecosystem of the Arctic, "it is of high interest to better understand the factors associated with such changes -- including the underlying causes," the article notes. -- "People should be aware that changes in the circulation of the Arctic Ocean could threaten the climate. It's not only the melting ice and animals losing their habitat that should be a concern," said Peigen Lin, lead author of the paper. Lin, who is an associate professor at the Shanghai Jiao Tong University's School of Oceanography in China, conducted his research as a postdoctoral investigator at the Woods Hole Oceanographic Institution (WHOI) in Massachusetts. -- With the gyre being the Arctic Ocean's largest freshwater reservoir, "if that freshwater gets released and ends up spreading into the North Atlantic, it could impact the overturning circulation, and, in an extreme case, disrupt it," said co-author Robert Pickart, a senior scientist in WHOI's Department of Physical Oceanography. -- The study, which includes an examination of long-term trends of the Beaufort Gyre and the causes of the thinning of the cold halocline layer, quantifies the evolution of the gyre in terms of its sea surface height as well as its freshwater content. "Both of these indicate that the Beaufort Gyre has stabilized in the second decade of this century," Lin said. -- The study also addresses the causes of the halocline thinning considerably as the gyre has evolved. The study notes that the recent decrease in the amount of Pacific origin winter water exiting the Chukchi Sea explains some of the thinning, and that the enhanced influence from the eastern Beaufort Sea -- due to the gyre's southeastward shift- likely also contributes to the thinning. [] Glacier, Ocean current, Reindeer (Caribou), Arctic fox, Muskox, Tundra, Carbon cycle, Rogue wave (oceanography) | 2319-E030 |
| NIH REF | KEY | HEADLINE | SUMMARY | SOURCE | JOURNAL | CONTENT | ITEM # |