Culture

Forest fragments surprising havens for wildlife

image: Researchers found that forest fragments outside of Sumatra's Bukit Barisan National Park were surprisingly rich in wildlife -- including critically endangered species such as Sumatran tiger (Panthera tigris sumatrae).

Image: 
WCS

Destruction of tropical rainforests reduces many unprotected habitats to small fragments of remnant forests within agricultural lands, and to date, these remnant forest fragments have been largely disregarded as wildlife habitat.

Researchers conducted camera trap surveys within Sumatra's Bukit Barisan Selatan National Park and five surrounding remnant forest fragments, finding 28 mammal species in the protected forest and 21 in the fragments--including critically endangered species such as Sunda pangolin (Manis javanica) and Sumatran tiger (Panthera tigris sumatrae), along with species of conservation concern such as marbled cat (Pardofelis marmorata) and Asiatic golden cat (Pardofelis temminckii).

The biodiversity found within the fragments suggests that these small patches of remnant forest may have conservation value to certain mammal species and indicates the importance of further research into the role these habitats may play in landscape-level, multispecies conservation planning.

Credit: 
Wildlife Conservation Society

Great Scots! 'it's' a unique linguistic phenomenon

A new study reveals that in a number of varieties of English spoken in Scotland, the rules of contraction (it's for it is) seem to differ unexpectedly, and asserts that such differences may shed new light on our understanding of language. The study, 'Syntactic variation and auxiliary contraction: the surprising case of Scots', by Gary Thoms (New York University), David Adger (Queen Mary University of London), Caroline Heycock (University of Edinburgh) and Jennifer Smith (University of Glasgow) will be published in September 2019 issue of the scholarly journal Language. A pre-print version of the article may be found at https://www.linguisticsociety.org/sites/default/files/LSA95302.pdf.

Contractions are widespread in English. However, there are certain rules about what can be contracted where--rules that speakers follow without ever having been taught them, and without being consciously aware of them. For example, speakers happily say It's in the box but not I don't know where it's. Such rules seem to apply to every variety of English, whether it be spoken in Philadelphia, London or the Caribbean.

The starting point for the article is the rule that forbids contraction in examples like I don't know where it's, which is one of the most exceptionless rules of contraction in English varieties. Previous work showed that the problem is the presence of a 'gap' directly after the contraction (I don't know where it's__), the idea being that the sentence starts as I don't know it is where, but we move the where back before the it is when we actually utter the sentence. Many modern theories of syntax involve the existence of these two "layers" of structure--the word order we speak and hear may come from an "underlying" order that is quite different.

In the article, the authors investigate what looks like a curiously specific exemption from this restriction found in some dialects of Scots: speakers readily allow contraction in examples like Here it's! or There it's!, which are used in the context of discoveries or sudden realizations (Where's my book??? Ah, there it's!). The authors seek to explain why contraction is possible just in these types of sentences, which they call locative discovery expressions, and only in one specific subpart of the English dialect continuum.

To investigate this, the authors analyzed data from the Scots Syntax Atlas, a new online digital resource for the study of Scots. The atlas provides original data on hundreds of grammatical phenomena from more than 140 locations across Scotland, gathered in face-to-face interviews by community-insider fieldworkers. The authors found out that many varieties of Scots also allow a kind of locative discovery expression where speakers repeat the word there (or here), so they say things like There it's there!. And it turns out that all speakers who can say There it's! can also say There it's there!, but not vice versa.

But - if in There it's there! the word conveying the location is that second there, that gets the accent, then what's the purpose of that first there? In Scots, the initial there has become simply a kind of particle, serving to introduce this kind of discovery expression but not conveying any actual meaning itself - it's a butler of sorts.

And what about the speakers who say not only There it's there! but also There it's!? The authors argue that in this group of speakers' minds, there is an unpronounced there after the verb. So for them There it's! doesn't violate the rule that it is can't contract to it's next to a gap left by moving something, because nothing did move. There is a silent there after the it's -- we could write it as There it's there!

This article shows that the general rules on contraction in English really are general. But more importantly, it demonstrates that these rules make reference to very abstract differences in grammatical structure: there is different from a gap __, even though they are both silent. What looked like a peculiar feature of Scots dialects turns out to provide evidence for speakers' unconscious knowledge of differences in structure between sentences, differences which are not directly perceived.

Credit: 
Linguistic Society of America

Rethinking seizures associated with cardiac disease

image: As suggested by its name, mutations in the gene seizure (sei for short) cause flies to become highly sensitive to heat stress. When ambient temperature goes up rapidly, wild type flies are able to escape these unfavorable conditions. In contrast, mutant flies are hypersensitive to heat and start seizing almost immediately. Hill et al. now show that the protective effect of sei comes from its activity in specific populations of neurons and glia cells in the fly brain. Shown are the neurons in the brain (top panel) and the ventral ganglion (bottom panel) (a structure homologous to the spinal cord), which express the sei protein (green). All other neurons are shown in magenta. The nuclei of all cells in the nerve cord are in blue.

Image: 
Yehuda Ben-Shahar, Washington University in St. Louis

Most people with a medical condition called long QT syndrome have a mutation in a gene that causes bouts of fast, chaotic heartbeats. They also experience fainting spells and seizures. The clinical approach has largely assumed that when the heart beats erratically, the brain eventually does not get enough oxygen -- which in turn causes the seizures.

Research from Washington University in St. Louis finds that mutations of a gene implicated in long QT syndrome in humans may trigger seizures because of their direct effects on certain classes of neurons in the brain -- independent from what the genetic mutations do to heart function. The new work from Arts & Sciences was conducted with fruit flies and is published August 8 in PLOS Genetics.

"This gene seems to be a key factor in the physiological process that protects neurons from starting to fire uncontrollably in response to a rapid increase in temperature, which could lead to paralysis and death," said Yehuda Ben-Shahar, associate professor of biology in Arts & Sciences.

Alexis Hill, recently a postdoctoral fellow in the Ben-Shahar laboratory, discovered this unexpected relationship as she probed the nervous system response to acute environmental stress.

Heat in general causes neurons to start firing faster, so the brain is particularly sensitive to overheating. Mammals and other large animals have ways to maintain their internal temperature and protect their brains from heat. But not the fruit fly. With no extra bulk in his tiny body, the only thing a fly can do to regulate temperature is to move from an uncomfortable spot to a comfortable one.

Ben-Shahar had previously published work showing flies that lack a gene called sei could not act to save themselves at temperatures above 25 degrees Celsius (77 Fahrenheit). They had no ability to buffer heat stress, and started having seizures as temperatures increased.

This gene sei -- named by other researchers who had previously discovered its role in seizure activity -- shows up in lots of places in fruit flies: in the neurons responsible for primary communication of both excitatory and inhibitory signals, in the glia cells of the nervous system that support neurons in various ways, and in the heart.

In their new work, Hill and Ben-Shahar were able to show that sei protects against heat-induced hyperexcitability only when it is expressed in a few particular classes of neurons and glia. Knocking down the gene in the heart had no effect on seizure activity.

"The ability of flies to resist the heat is in neurons that release neurotransmitters that make other neurons fire faster, the ones that excite neurons," Ben-Shahar said.

Surprisingly, the study also uncovered a protective role for sei in glia, the other primary cell of the nervous system. Glia have traditionally been overshadowed by the importance of neurons, but in recent years they have been emerging as equally important in maintaining healthy brain functions. The fact that this work identifies a protective role of an ion channel in glia further supports the idea that glia have much broader physiological functions in the nervous system and how it might respond to environmental challenges, the researchers said.

A careful look through the scientific literature reveals many references to seizure associated with long QT syndrome, which afflicts human beings with a genetic mutation to a sei-comparable gene called hERG.

But most clinical practitioners assume that these seizures are a secondary outcome of cardiovascular disease. Ben-Shahar hopes this soon will change.

"If you look at population statistics, there is a much higher incidence of seizures in long QT patients than in the general population," he said. "Because cardiovascular dysfunction can cause all kinds of problems, in the literature right now it is assumed that the seizures are secondary -- that because the people have a sick heart they end up developing seizures and other things.

"It's possible, based on our data, that it's two independent effects. Because if the mutation is affecting the function of the gene in the heart, it will affect the function in the neurons.

"And in flies, it's not going to kill neurons," Ben-Shahar said. "We know that we can completely eliminate this gene from the fly genome -- and flies will develop normally, mostly. Yet they become extremely sensitive to environmental (conditions). It's possible that that's exactly what's happening in people -- that it's completely independent."

Credit: 
Washington University in St. Louis

Analysis and detoxification in one step

Many industrial and agriculture processes use chemicals that can be harmful for workers and the ecosystems where they accumulate. Researchers from Thailand have now developed a bioinspired method to detect and detoxify these chemicals in only one step. As they report in the journal Angewandte Chemie, a combination of two natural enzymatic reactions convert harmful chloro- and nitrophenols into the substance that causes the characteristic glowing of fireflies: luciferin.

Oxygenated benzene or phenol molecules are part of the chemical structure of many organic substances, from lignin and tar, to pharmaceuticals, dyes, and herbicides. Phenol-derived compounds are added to plastics as plasticizers. Although many of these chemicals are not harmful as such, pesticides, herbicides, or flame retardants may degrade to cancerous and stable nitrophenols and halogenated phenols that accumulate in the workplace or in fields.

Phenolic compounds are usually detected with techniques such as mass spectrometry. Biochemist Pimchai Chaiyen at the Vidyasirimedhi Institute of Science and Technology, Thailand, and colleagues, have now developed a more practical approach. They combined an established biodetoxification method with chemical and biochemical conversion schemes to detect and remove contaminants in one step. The key product is witnessed widely on summer nights in gardens and in the countryside: luciferin--the bioluminescent compound produced by fireflies.

Nature has developed several mechanisms to degrade and detoxify chemicals. Bacteria use specialized enzymes to dehalogenate phenols and convert them into oxidized compounds called benzoquinones, which can be metabolized by organisms. Enzymes called dehalogenases or mono-oxygenases have thus been used in industry for biological detoxification.

Chaiyen and colleagues went further than pure detoxification and coupled the enzymatic process with a method to convert the benzoquinone product into luciferin. "The developed chemoenzymatic cascade offers additional value: it provides biodetection technology for nitrophenols and halogenated phenols," they claim. The chemoenzymatic cascade entails conversion of the product from the first enzymatic conversion step, benzoquinone, into luciferin in a second step, but within the same reaction vessel.

To achieve conversion of benzoquinone into luciferin, the authors added the natural compound cysteine to the reaction mixture. They then included a third step in the reaction sequence and detected the luciferin product through the glowing reaction caused by an enzyme called luciferase, which is also present in fireflies. The authors also proved that their detoxification-luciferin production and detection scheme was robust and capable of quantitative conversion of hazardous phenols into luciferin.

Simultaneous detoxification and luciferin production may offer additional benefits. Luciferin is a highly valued compound in biomedicine. The authors point out that their approach is a remarkably straightforward and useful strategy for analysis and detoxification of the workplace in one step, and it can be used to synthesize luciferin from waste chemicals.

Credit: 
Wiley

Typhoon Krosa follows leader Supertyphoon Lekima

image: NASA's Earth Observing System Data and Information System (EOSDIS) Worldview application provides the capability to interactively browse over 700 global, full-resolution satellite imagery layers and then download the underlying data. Many of the available imagery layers are updated within three hours of observation, essentially showing the entire Earth as it looks "right now." This NOAA NASA Suomi NPP satellite image was collected on August 08, 2019.

Image: 
Image Courtesy: NASA Worldview, Earth Observing System Data and Information System (EOSDIS).

NOAA-NASA's Suomi NPP satellite captured this image using NASA's Earth Observing System Data and Information System (EOSDIS) Worldview application on Aug. 08, 2019 and it shows Supertyphoon Lekima heading towards the coast of China as Typhoon Krosa brings up the rear moving slowly towards Japan.

Typhoon Krosa is currently located 167 nautical miles southwest of Iwo To, Japan.  It is slowly tracking northeastward at one knot over the past six hours making it quasi-stationary as it intensified and maintained its 14 nautical mile eye.

Krosa's winds are steady at approximately 100 knots (115 mph) which on the Saffir-Simpson hurricane scale would make this storm just over the Category 3 designation.

Like Lekima, Krosa is able to intensify due to low vertical wind shear and warm sea surface temperatures in the area of 30 degrees C (86 degrees F) both of which are favorable to typhoon development and intensification.

For the time being, Krosa will remain quasi-stationary and continue to intensify for the next 12 hours.  Then the equatorial ridge nearby will steer the storm northeastward. The subtropical ridge will rebuild and steer north-northwestward toward Japan.  Krosa will gradually weaken over the next five days, still maintaining typhoon strength throughout that period.

Credit: 
NASA/Goddard Space Flight Center

Where are the bees? Tracking down which flowers they pollinate

Bees are in vast decline in the UK and across Europe, as are the wildflowers on which they rely. Bees have an essential role in our ecosystems and a third of all our food is dependent on their pollination; just in economic worth, pollination by bees is annually estimated at £265 billion, worldwide.

The main risks to bees include wide-spread pesticide use in agriculture, parasites, disease and climate change, and crucially - the loss of valuable biodiversity which poses a further threat to bees and other wild pollinators. One way to help boost their numbers is by planting the correct wildflowers, providing a better habitat for pollinators to disperse, nest and breed.

However, it is unclear which plant species are the most preferred between different pollinators, including bees, and how this might change over time and in different environmental conditions. In agriculture, farmers want to know that the pollinators are actually visiting the plants they need them to. Historically, scientists used light microscopy to identify individual bee-collected pollen grains, which was a time-consuming and impractical method.

To obtain a more accurate understanding without the need for laborious manual inspection of pollen, scientists have developed a rapid analysis method called 'Reverse Metagenomics' (RevMet) that can identify the plants that individual bees visit using the MinION, a portable DNA sequencer from Oxford Nanopore Technologies.

The portability of the equipment involved means that this type of analysis could be performed on-site where bees are collected and sampled - vastly increasing our understanding of where bees look for pollen on a national scale.

Ned Peel, the PhD student who carried out the research in the Leggett Group at EI: "Importantly, from a mixed sample of pollen, as well as being able to work out what species of plant bees have visited, we can also measure the relative quantities of each type of pollen. This type of analysis can be applied not only to conserving pollinators but to helping us to sustainably improve crop production that relies on pollinators."

Previous costly and inefficient manual methods to measure pollen and other genomics methods, such as metabarcoding, have been developed - but these can't accurately measure how much of each different type of pollen is found in a sample.

Ned goes on to explain the new genomics method further: "In standard metagenomics, short stretches of DNA from mixed samples are compared to whole genomes, which can be expensive to generate. In collaboration with UEA's School of Biological Sciences, who performed the ecological side of the research - collecting bees and plant samples - we discovered that we could conduct the analysis using 'reference skims' instead.

"To make a skim, we carry out really cheap sequencing that only partially covers the complete genome of the plants, but this is enough when compared with the long reads from the MinION to identify plants. In our work, we generated skims of 49 different wild UK plant species."

This technique can reliably differentiate species in a mixed sample according to the amount of DNA present of each. The results showed that honeybees, and two species of bumblebee, demonstrate a high preference for one plant species per foraging trip."

The reverse metagenomics pipeline can be applied to more questions than just what plants bees like to pollinate; we can also understand whether certain wildflowers compete with agricultural flowers for pollinators, or the behaviour of pollinators across large areas and land types.

The method could also be used to study other mixed samples, such as herbivore dung, for diet analysis; and air, to identify airborne allergenic pollen and crop pathogens.

Credit: 
Earlham Institute

Ethiopian rock shelter earliest evidence of high-altitude prehistoric life

Archaeologists have uncovered the earliest evidence of high-altitude prehistoric living in the form of a rock shelter in Ethiopia, though whether the site was inhabited permanently is unclear. According to the report - based on archeological, biogeochemical, glacial chronological and other analyses - more than 30,000 years ago, the Fincha Habera rock shelter, a site situated more than 11,000 feet above sea level in the Bale Mountains of Ethiopia, was home to Middle Stone Age foragers who made use of nearby resources and feasted upon plentiful giant mole-rats. Life at high-altitude imposes a number of limitations and stresses on the human body. Because of this, it has long been assumed that the peopling of high-elevation environments - those more than 2,500 meters above sea level (masl) - has only recently occurred in human history. However, from the Andean altiplano to the Tibetan Plateau, a growing number of new archaeological finds in high places across the globe has begun to show otherwise. Still, these sites are rare, and much remains to be discovered about the nature of human high-altitude settlements. Following excavations at Fincha Habera, which the team approached on foot or by pack horse , as well as based on archaeological surveys and paleoenvironmental analyses, Götz Ossendorf and colleagues present results that push back the antiquity of a human presence at high elevation. They report thousands of Middle Stone Age (MSA) artifacts, including locally collected stones, burnt animal bones, and the hearths of former fires. Radiocarbon dates from the site's earliest contexts suggest that occupation began during the Late Pleistocene, sometime between 47,000 and 31,000 years ago. While the environment enabled long-term stays at Fincha Habera repeatedly over several thousand years, the authors say, the permanence of these occupations cannot be proven nor refuted. In a related Perspective, Mark Aldenderfer discusses Ossendorf et al.'s findings in the context of recent high-altitude studies, some of which present conclusions largely unsupported by underlying data. "Words matter, and it's time for archaeologists working on the world's high plateaus to be more deliberate about the terms they use to describe and frame their findings," writes Aldenderfer. To that end, he describes the restraint applied in descriptions in the report by Ossendorf's team as "admirable."

Credit: 
American Association for the Advancement of Science (AAAS)

Novel strategy uncovers potential to control widespread soilborne pathogens

image: The effects of microbial volatile organic compound exposure on the viability of sclerotia of Sclerotinia sclerotiorum were evaluated in a microscopy-based approach. Green indicates intact hyphae; and red indicates damaged hyphae. A and B, Untreated sclerotia; C, Sclerotia treated with Pseudomonas helmanticensis Sc-B94; and D, Sclerotia treated with Buttiauxella

Image: 
Pascal Mülner, Alessandro Bergna, Philipp Wagner, Dženana Sarajli?, Barbara Gstöttenmayr, Kristin Dietel, Rita Grosch, Tomislav Cernava, and Gabriele Berg.

St. Paul, MN (August 2019)--Soilborne pathogens are a major issue worldwide as they can infect a broad range of agricultural plants, resulting in serious crop losses devastating to farmers. These persistent pathogens are often resistant toward chemical fungicides, making them difficult to control, and have a broad host range, enabling them to damage a variety of important crops.

Some of these pathogens have the ability to form survival bodies called sclerotia that can survive for many years in the soil before they cause infection and disease in new plant generations. Other microorganisms often form stable associations with these sclerotia, resulting in a complex system teeming with fungal pathogens and non-pathogenic bacteria.

A team of scientists based in Austria and Germany analyzed the microorganisms within the sclerotia of soilborne fungal pathogens from genera Rhizoctonia and Sclerotinia in attempt to discover effective control methods. In these microorganisms, the team found specific bacterial communities different from both the surrounding soil and the host plants affected by the pathogens.

They extracted samples from these communities and through additional analysis discovered that several of the bacteria can produce volatile compounds (small chemicals that easily disperse) with the potential to reduce the viability of the pathogens. The team also found that specific combinations of these bacteria can even more effectively counteract the pathogens.

This study, published in the completely open access Phytobiomes Journal, introduces a new strategy for identifying antagonistic bacteria, which can then be used to control important plant pathogens. These findings suggest that biological control of pathogens might be improved by combining different beneficial microorganisms and highlight novel strategies used to control widespread phytopathogenic fungi.

Also of note, this study "shows how a multi-phasic approach combining different disciplines (microbiology, molecular biology and analytical chemistry) can be implemented to find new solutions for plant protection," according to co-author Tomislav Cernava.

Credit: 
American Phytopathological Society

Why humans in Africa fled to the mountains during the last ice age

image: The Fincha Habera rock shelter in the Ethiopian Bale Mountains served as a residence for prehistoric hunter-gatherers.

Image: 
Götz Ossendorf

People in Ethiopia did not live in low valleys during the last ice age. Instead they lived high up in the inhospitable Bale Mountains. There they had enough water, built tools out of obsidian and relied mainly on giant rodents for nourishment. This discovery was made by an international team of researchers led by Martin Luther University Halle-Wittenberg (MLU) in cooperation with the Universities of Cologne, Bern, Marburg, Addis Ababa and Rostock. In the current issue of "Science", the researchers provide the first evidence that our African ancestors had already settled in the mountains during the Palaeolithic period, about 45,000 years ago.

At around 4,000 metres above sea level, the Bale Mountains in southern Ethiopia are a rather inhospitable region. There is a low level of oxygen in the air, temperatures fluctuate sharply, and it rains a lot. "Because of these adverse living conditions, it was previously assumed that humans settled in the Afro-Alpine region only very lately and for short periods of time," says Professor Bruno Glaser, an expert in soil biogeochemistry at MLU. Together with an international team of archaeologists, soil scientists, palaeoecologists, and biologists, he has been able to show that this assumption is incorrect. People had already begun living for long periods of time on the ice-free plateaus of the Bale Mountains about 45,000 years ago during the Middle Pleistocene Epoch. By then the lower valleys were already too dry for survival.

For several years, the research team investigated a rocky outcrop near the settlement of Fincha Habera in the Bale Mountains in southern Ethiopia. During their field campaigns, the scientists found a number of stone artefacts, clay fragments and a glass bead. "We also extracted information from the soil as part of our subproject," says Glaser. Based on the sediment deposits in the soil, the researchers from Halle were able to carry out extensive biomarker and nutrient analyses as well as radiocarbon dating and thus draw conclusions as to how many people lived in the region and when they lived there. For this work, the scientists also developed a new type of palaeothermometer which could be used to roughly track the weather in the region - including temperature, humidity and precipitation. Such analyses can only be done in natural areas with little contamination, otherwise the soil profile will have changed too much by more recent influences. The inhospitable conditions of the Bale Mountains present ideal conditions for such research since the soil has only changed on the surface during the last millennia.

Using this data, the researchers were not only able to show that people have been there for a longer period of time. The analyses may also have uncovered the reasons for this: during the last ice age the settlement of Fincha Habera was located beyond the edge of the glaciers. According to Glaser, there was a sufficient amount of water available since the glaciers melted in phases. The researchers are even able to say what people ate: giant mole rats, endemic rodents in the region the researchers investigated. These were easy to hunt and provided enough meat, thereby providing the energy required to survive in the rough terrain. Humans probably also settled in the area because there was deposit of volcanic obsidian rock nearby from which they could mine obsidian and make tools out of it. "The settlement was therefore not only comparatively habitable, but also practical," concludes Glaser.

The soil samples also reveal a further detail about the history of the settlement. Starting around 10,000 years before the Common Era, the location was populated by humans for a second time. At this time, the site was increasingly used as a hearth. And: "For the first time, the soil layer dating from this period also contains the excrement of grazing animals," says Glaser.

According to the research team, the new study in "Science" not only provides new insights into the history of human settlement in Africa, it also imparts important information about the human potential to adapt physically, genetically and culturally to changing environmental conditions. For example, some groups of people living in the Ethiopian mountains today can easily contend with low levels of oxygen in the air.

Credit: 
Martin-Luther-Universität Halle-Wittenberg

Mega-cloud from Canadian wildfires will help model impacts of nuclear war

image: An enormous cloud of smoke from intense wildfires drifted over northern Canada on August 15, 2017. The image is a mosaic composed from several satellite overpasses because the affected area was so large.

Image: 
NASA Earth Observatory

Extreme wildfires in British Columbia, Canada, pumped so much smoke into the upper atmosphere in August 2017 that an enormous cloud circled most of the Northern Hemisphere - a finding in the journal Science that will help scientists model the climate impacts of nuclear war.

The pyrocumulonimbus (pyroCb) cloud - the largest of its kind ever observed - was quickly dubbed "the mother of all pyroCbs." When the smoke reached the lower stratosphere, it was heated by sunlight and "self-lofted" from 7 to 14 miles up within two months. The pivotal ingredient was black carbon (soot), which absorbed solar radiation, heating the air and fueling the smoke's rapid rise. The smoke lasted more than eight months because the stratosphere has no rain to wash it out.

"This process of injecting soot into the stratosphere and seeing it extend its lifetime by self-lofting, was previously modeled as a consequence of nuclear winter in the case of an all-out war between the United States and Russia, in which smoke from burning cities would change the global climate," said co-author Alan Robock, a distinguished professor in the Department of Environmental Sciences at Rutgers University-New Brunswick.

"Even a relatively small nuclear war between India and Pakistan could cause climate change unprecedented in recorded human history and global food crises," said Robock, who works in the School of Environmental and Biological Sciences.

The scientists used a state-of-the art climate model from the National Center for Atmospheric Research to model the lofting and movement of the colossal Canadian wildfire smoke cloud. The modeling considered smoke characteristics such as the ratio of soot to other ingredients and the rate at which ozone in the upper atmosphere broke down the smoke.

The smoke cloud contained only about 0.3 million tons of soot, while a nuclear war between India and Pakistan could produce 15 million tons and a U.S. vs. Russia war could generate 150 million tons. Still, the scientists validated their previous theories and the climate model they're using for ongoing research on nuclear war impacts by studying the wildfire, according to Robock.

The observed rapid rise of the smoke plume, its spread and photochemical reactions in the ozone layer provide new insights into the potential global climate impacts from nuclear war, the study says.

The next steps, as part of a Rutgers nuclear conflict climate modeling project, are to use refined nuclear war scenarios to determine the potential impact on the climate and food production on land and in the ocean, along with the potential for global famine. What the scientists learned from the wildfire modeling will make their new work more accurate and credible.

Credit: 
Rutgers University

Researchers discover why intense light can protect cardiovascular health

AURORA, Colo. (Aug. 8, 2019) - Researchers at the University of Colorado Anschutz Medical Campus have found that intense light amplifies a specific gene that bolsters blood vessels and offers protection against heart attacks.

"We already knew that intense light can protect against heart attacks, but now we have found the mechanism behind it," said the study's senior author Tobias Eckle, MD, PhD, professor of anesthesiology at the University of Colorado School of Medicine.

The study was published recently in the journal Cell Reports.

The scientists discovered that housing mice under intense light conditions for one week `robustly enhances cardio protection', which resulted in a dramatic reduction of cardiac tissue damage after a heart attack. They also found that humans could potentially benefit from a similar light exposure strategy.

In an effort to find out why, they developed a strategy to protect the heart using intense light to target and manipulate the function of the PER2 gene which is expressed in a circadian pattern in the part of the brain that controls circadian rhythms.

By amplifying this gene through light, they found that it protected cardiovascular tissues against low oxygen conditions like myocardial ischemia, caused by reduced oxygen flow to the heart.

They also discovered that the light increased cardiac adenosine, a chemical that plays a role in blood flow regulation.

Mice that were blind, however, enjoyed no cardio protection indicating a need for visual light perception.

Next, they investigated whether intense light had similar effects on healthy human volunteers. The subjects were exposed to 30 minutes of intense light measured in lumens. In this case, volunteers were exposed to 10,000 LUX, or lumens, on five consecutive days. Researchers also did serial blood draws.

The light therapy increased PER2 levels as it did in mice. Plasma triglycerides, a surrogate for insulin sensitivity and carbohydrate metabolism, significantly decreased. Overall, the therapy improved metabolism.

Eckle has long known that light plays a critical role in cardiovascular health and regulating biological processes. He pointed out that past studies have shown an increase in myocardial infarctions during darker winter months in all U.S. states, including sunnier places like Arizona, Hawaii and California. The duration of the light isn't as important as the intensity, he said.

"The most dramatic event in the history of earth was the arrival of sunlight," Eckle said. "Sunlight caused the great oxygen event. With sunlight, trillions of algae could now make oxygen, transforming the entire planet."

Eckle said the study shows, on a molecular level, that intensive light therapy offers a promising strategy in treating or preventing low oxygen conditions like myocardial ischemia.

He said if the therapy is given before high risk cardiac and non-cardiac surgery it could offer protection against injury to the heart muscle which can be fatal.

"Giving patients light therapy for a week before surgery could increase cardio protection," he said. "Drugs could also be developed that offer similar protections based on these findings. However, future studies in humans will be necessary to understand the impact of intense light therapy and its potential for cardio protection."

Credit: 
University of Colorado Anschutz Medical Campus

Tobacco plant 'stickiness' aids helpful insects, plant health

image: The spined stilt bug gets a meal while helping eliminate a tobacco pest.

Image: 
Peter Nelson

Researchers at North Carolina State University have shown that "sticky" hairlike structures on tobacco leaves can help attract beneficial insects that scavenge on other insects trapped on the leaves, increasing leaf yield and reducing pest damage to plant structures.

In a study examining pests of tobacco plants and opportunistic insects that eat the pests, researchers show that sticky glandular trichomes on tobacco leaves trap insects that aren't adapted to interacting with perilous plant surfaces. The trapped insects perish and then become food for the spined stilt bug (Jalysus wickhami) - a small but long-legged insect predator that has a beneficial relationship with tobacco plants.

Tobacco plants provide a trapped-insect buffet that spined stilt bugs are more than happy to feast upon, which helps protect the plant from pest infestation and damage. Better still, the spined stilt bug - which uses its long legs as leverage to navigate across the sticky parts of tobacco leaves to reach its bug banquet - isn't harmful to tobacco plants, researchers say, although it drinks some sap from tobacco plants to stay hydrated between pest meals.

"A sticky plant isn't a dead end for all insects; some actually prefer sticky plants and take advantage of the difficult plant surface," said Peter Nelson, an NC State Ph.D. graduate and lead author of a paper describing the study.

"By taking a closer look at how insects interact with plants, we might be able to take advantage of unique interactions for pest management," Nelson added. "Our review of the literature found that over 25 economically important plants have sticky surfaces that trap insects and might benefit from the same type of interaction with predatory arthropods."

"This is a mutualistic relationship previously unrecognized on domesticated tobacco plants," said Clyde Sorenson, Alumni Association Distinguished Undergraduate Professor of Entomology at NC State and corresponding author of the paper. "The academic literature shows a number of wild flowers with similar symbiotic relationships with predators to reduce damage to the plant, but tobacco is the first economically important plant to show this mutualistic relationship."

In the study, the abundance of spined stilt bugs grew when researchers added dead fruit flies (Drosophila melanogaster) to the leaves of tobacco plants in greenhouse and field settings. Increased leaf yield - the primary economic consideration for tobacco farmers - and less damage to tobacco plant structures resulted when additional fruit flies were added to leaves.

The study also showed that insecticide use did not affect pest entrapment by sticky glandular trichomes. Plants treated with imidacloprid, a common tobacco insecticide, had fewer spined stilt bugs than untreated plants, but that did not significantly affect pest densities or plant health.

Surprisingly, the study showed that densities of pests like the tobacco budworm on tobacco leaves did not decrease, even though more spined stilt bugs were present.

"We're not completely sure about why this counterintuitive finding occurred, although one hypothesis is that the increased number of predator stilt bugs may trigger a behavioral response in the tobacco budworm and other pests to feed less on tobacco plants," Sorenson said.

Sorenson said the results could lead to further improvement or manipulation of glandular trichomes.

"We don't expect farmers to throw dead fruit flies on 40 acres of a tobacco crop, but recognizing the effects of beneficial insects and how these mutually beneficial relationships work is important," he said. "Plus, these types of effects may occur in other economically important crops with glandular trichomes, like tomatoes."

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North Carolina State University

New process discovered to completely degrade flame retardant in the environment

image: The paper is featured on the cover of Environmental Science & Technology.

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ES&T

A team of environmental scientists from the University of Massachusetts Amherst and China has for the first time used a dynamic, two-step process to completely degrade a common flame-retardant chemical, rendering the persistent global pollutant nontoxic.

This new process breaks down tetrabromobisphenol A (TBBPA) to harmless carbon dioxide and water. The discovery highlights the potential of using a special material, sulfidated nanoscale zerovalent iron (S-nZVI), in water treatment systems and in the natural environment to break down not only TBBPA but other organic refractory compounds that are difficult to degrade, says Jun Wu, a visiting Ph.D. student at UMass Amherst's Stockbridge College of Agriculture and lead author of the paper published in Environmental Science & Technology.

"This is the first research about this dynamic, oxic/anoxic process," Wu says. "Usually, reduction or oxidation alone is used to remove TBBPA, facilitated by S-nZVI. We combined reduction and oxidation together to degrade it completely."

Wu emphasizes that "the technique is technically simple and environmentally friendly. That is a key point to its application."

The research is featured on the cover of ES&T, which is widely respected for publishing papers in the environmental disciplines that are both significant and original.

"This research can lead to a decrease in the potential risk of TBBPA to the environment and human health," says Wu, who began the research at the University of Science and Technology of China in Hefei. At UMass Amherst, Wu works in the pioneering lab of Baoshan Xing, professor of environmental and soil chemistry, corresponding author of the new study and one of the world's most highly cited researchers.

"Our research shows a feasible and environmentally friendly process to completely degrade refractory brominated ?ame retardants in a combined oxic and anoxic system," Xing says. "This is important for getting rid of these harmful compounds from the environment, thus reducing the exposure and risk."

Among the most common flame retardants that hinder combustion and slow the spread of fire, TBBPA is added to manufactured materials, including computer circuit boards and other electrical devices, papers, textiles and plastics.

Associated with a variety of health concerns, including cancer and hormone disruption, TBBPA has been widely detected in the environment, as well as in animals and human milk and plasma.

Although Wu and Xing's research breaks new ground in the efforts to develop safe and effective processes to remediate groundwater and soil contaminated with TBBPA, they say more research is needed to learn how to best apply the process.

Their research was supported by grants from the National Natural Science Foundation of China and the USDA-National Institute of Food and Agriculture's Hatch Program.

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University of Massachusetts Amherst

Restructuring Medicare Shared Savings Program can yield 40% savings in health costs

CATONSVILLE, MD, August 8, 2019 - More than a trillion dollars was spent on healthcare in the United States in 2018, with Medicare and Medicaid accounting for some 37% of those expenditures. With healthcare costs expected to continue to rise by roughly 5% per year, a continued debate in healthcare policy is how to reduce costs without compromising quality.

As part of this effort, the Medicare Shared Savings Program was created to control escalating Medicare spending by giving healthcare providers incentives to deliver more efficient healthcare.

New research published in the INFORMS journal Operations Research offers a new approach that could substantially change the healthcare spending paradigm by utilizing performance-based incentives to drive down spending.

The researchers Anil Aswani and Zuo-Jun (Max) Shen of the University of California, Berkeley, and Auyon Siddiq of the University of California, Los Angeles found that redesigning the contract for the shared savings program to better align provider incentives with performance-based subsidies can both increase Medicare savings and increase providers' reimbursement payments.

"Introducing performance-based subsidies can boost Medicare savings by up to 40% without compromising provider participation in the shared savings program," said Aswani, a professor in the Industrial Engineering and Operations Research Department at UC Berkeley. "This contract can lead to improved outcomes for both Medicare and participating providers," he continued.

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Institute for Operations Research and the Management Sciences

Depression is the single largest predictor of substance use during pregnancy

image: Researchers Rachel Brown, an MSc Candidate, and Jamie Seabrook, PhD, studied health data from 25,000 pregnant women and have shown that depression is the largest driver of substance use during pregnancy.

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Schulich Medicine & Dentistry, Western University

It is well known that tobacco, alcohol, and cannabis use during pregnancy are associated with poor birth outcomes, yet many women continue to use these substances during pregnancy.

Researchers at Western University and its affiliate Brescia University College have now shown that depression is the single largest driver of substance use during pregnancy, highlighting the need for greater supports for the mental health of pregnant mothers.

The research team analyzed health and geographical data gathered through Lawson Health Research Institute from more than 25,000 pregnant women in Southwestern Ontario.

"Pregnant women who were depressed were 2.6 times more likely to use cannabis and twice as likely to smoke cigarettes and use alcohol while pregnant," said Jamie Seabrook, PhD, and Associate Professor at Brescia and Western's Schulich School of Medicine & Dentistry, and Scientist at Children's Health Research Institute, a Lawson program. "We don't know when the substance use first began but we do know that it was continuing during pregnancy and that is a big risk factor for poor maternal and infant health outcomes."

The study, published in the Journal of Neonatal-Perinatal Medicine, is the first Canadian study with a sample size this large to show that depression during pregnancy is the primary risk factor for cannabis, tobacco and alcohol use, and is more important than education, income, or age.

"This really highlights the importance of programming for mental health, including mental health promotion strategies, psychotherapy and safe and proper medication for mental health during pregnancy," said Rachel Brown, an MSc candidate and first author on the paper. "The research shows that there is an effect later on in life as well with infants that are born preterm or low birth weight. To intervene or advocate for mental health programs for the mom, the idea is that it sets up the health of the infants later on in life."

The research team points out that this research is especially important in Canada with the recent legalization of recreational cannabis.

"Let's help women with their mental health to improve their overall health and in doing so, improve the health of their baby," said Seabrook.

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University of Western Ontario