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Straw incorporation--shredding and burying straws--has been widely promoted as an environmentally friendly method to increase soil organic carbon stocks and improve soil fertility. Scientists have also found crop straw incorporation could help reduce ammonia volatilization from fertilized fields, which contributes to the formation of fine particles thereby resulting in serious air pollution. Still, scientists are not clear about the long-term effects, e.g. 15 years, of crop straw incorporation approaches and rates on ammonia volatilization from calcareous soils, which are hotspots for agricultural ammonia volatilization.

Recently, Dr. Zhou Minghua and his team from the Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, investigated the effects of different long-term straw management practices on ammonia volatilization from calcareous agricultural soils under a subtropical climate. Their findings were recently published in Atmospheric and Oceanic Science Letters.

"We find long-term crop straw incorporation practices could reduce annual ammonia volatilization fluxes by 16.1% to 35.1%. The magnitude of the inhibition effect increased along with the increasing straw application rate," says Zhou, the corresponding author of the study. "The inhibition effect is likely because the high C/N ratio of crop straw can increase microbial N immobilization and enhance the ammonium transformation [e.g., nitrification]".

Zhou also points out that straw burning, a traditional practice carried out by Chinese peasants but strongly discouraged by the Chinese government owing to concerns around air pollution, resulted in one-third higher annual ammonia volatilization as compared with incorporation of the same amount of unburned crop straw.

Taking into consideration both agronomical (e.g., soil fertility) and environmental performances, this study suggests that long-term crop straw incorporation could be a wise way for reducing ammonia volatilization while sustaining agricultural development.

Cribellate spiders spin thousands of tiny nanofibers into sticky threads. To keep from getting caught in their own webs, these spiders use a nonstick comb on their back legs. Now, researchers reporting in ACS Applied Nano Materials have patterned an antiadhesive nanostructure inspired by this comb onto a foil surface, creating a handy tool to control sticky lab-made nanomaterials for medical, smart textile and other applications. Watch a video of the combs in action here.

Unlike most spiders, which produce silk coated in a sticky glue, cribellate spiders' threads resemble a bristly wool that embeds into the bodies of their prey. During web-making, the spider's comb, or calamistrum, grabs onto the nanofibers emerging from its abdomen and assembles them into threads. Anna-Christin Joel and colleagues wondered why the sticky nanofibers don't cling to the spider's comb. They figured that the answer could reveal new strategies for handling synthetic nanomaterials and nanofibers, which can be tacky.

The researchers began by shaving off the calamistrum from a group of "lace weaver" spiders. In contrast to normal spiders, those lacking combs showed a buildup of nanofibers where the comb should have been. The team also observed that in normal spiders, the surface of the comb was covered with fingerprint-like nanoripples. They found that this structure prevents nanofibers from closely contacting the surface of the spider's leg in the region of the comb, reducing adhesive van der Waals forces. To make an artificial nonstick surface inspired by the spiders' combs, the researchers used lasers to pattern similar nanostructures onto poly(ethylene terephthalate) (PET) foils and then coated the foils with gold. When tested for antiadhesive properties against spider silk, the artificial comb performed almost as well as the natural version.

The authors acknowledge funding from the European Union's Horizon 2020 research and innovation program, the Excellence Initiative of the German federal and state governments and the Deutsche Forschungsgemainschaft.

The abstract that accompanies this article can be viewed here.

The American Chemical Society (ACS) is a nonprofit organization chartered by the U.S. Congress. ACS' mission is to advance the broader chemistry enterprise and its practitioners for the benefit of Earth and its people. The Society is a global leader in providing access to chemistry-related information and research through its multiple research solutions, peer-reviewed journals, scientific conferences, eBooks and weekly news periodical Chemical & Engineering News. ACS journals are among the most cited, most trusted and most read within the scientific literature; however, ACS itself does not conduct chemical research. As a specialist in scientific information solutions (including SciFinder® and STN®), its CAS division powers global research, discovery and innovation. ACS' main offices are in Washington, D.C., and Columbus, Ohio.

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A new tool maps the threats to the tropical dry forests in Peru and Ecuador. Bioscience engineers at KU Leuven combined data on possible threats to these forests - including fires and overgrazing - with data on the vulnerability of local tree species to these dangers, which the team estimated on the basis of species traits such as bark thickness and edibility of the leaves. The result is an online tool that local governments and NGOs can use to restore and conserve forests.

The tropical dry forests in Peru and Ecuador are under considerable strain due to fires, overgrazing, and overexploitation, among other things. And then there's climate change as well. In collaboration with the international research institution Bioversity International, researchers from the Division of Forest, Nature and Landscape at KU Leuven developed a model that advises local governments and NGOs on how to restore and conserve these forests.

Unique model thanks to tree traits

What makes the KU Leuven model unique is the combination of the threats that a forest is exposed to with the traits of local tree species. "Due to this combination of factors, our model provides an accurate representation of the resilience of a forest and its tree species," says doctoral student Tobias Fremout (KU Leuven), who is the lead author of this study. "A forest that mostly consists of trees with edible or 'palatable' leaves will be much more sensitive to overgrazing, for instance. Trees that are very useful for firewood, by contrast, are much more likely to suffer from overexploitation."

The possible threats to a forest were divided into five categories: fire, habitat conversion, overexploitation, overgrazing, and climate change. These categories, in turn, were combined with several traits of tree species, including bark thickness, usability as firewood or timber, and growth rates.

Tobias Fremout was able to map more than 40,000 km2 of (former) forest and 50 tree species. He combined all this information in an online vulnerability assessment tool.

Conservation, restoration or a seed bank

It was a very deliberate decision to make the tool available to local governments. "The online tool is freely accessible on the Internet. Local governments can consult it to check for each tree species where it is most at risk due to which specific threat," Tobias Fremout explains. This allows local governments to engage with the conservation and restoration of their forests in a very deliberate way. "The Peruvian authorities are aware of the enormous strain their forests are under, but their restoration efforts are sometimes still ill-considered. Via our tool, the authorities can see which species they should replant where, but especially also from which risks they should protect that specific area. After all, it's hardly useful to replant trees with edible leaves without also providing a fence to keep away cows and goats."

Replanting often seems to be the most logical choice. Due to climate change, however, it may not always be the smartest option. "We have used five climate models to predict whether, in the future, the regions under consideration will still offer the right circumstances for the tree species that are currently found there. If certain species are likely to get difficulties in particular areas, it's a better idea to replant these species elsewhere or to store seeds in a seed bank," Tobias Fremout continues.

Also useful in other countries

As the model developed by Tobias Fremout and his colleagues uses existing data on threats to tree species and traits, the model can also be translated to tropical forests in regions such as Africa or Asia. "To map the risk of forest fires, for instance, we used NASA observations. This information is available for the entire world and can, therefore, also be used for Cameroon or Indonesia, for instance. The characteristics of African and Asian trees are known and can be used in our model."

COLUMBUS, Ohio - Feeling prepared and confident about a job interview you have tomorrow is great. But a new study suggests that you may bring that sense of confidence into other parts of your life for which you might not be nearly so prepared.

In three studies, researchers found that feelings of preparedness in one area made people more confident in their beliefs about something completely different - whether those thoughts were positive or negative.

The findings suggest that people may sometimes feel confident about a belief or decision for totally unrelated reasons, said Patrick Carroll, lead author of the study and associate professor of psychology at The Ohio State University at Lima.

For example, you may have been leaning slightly toward support of one candidate in a local election when you started preparing for a job interview. Once you're prepared for the interview and are feeling confident, you may find that you're suddenly sure about your support for that candidate.

"You're going to feel a general sense of confidence as a result of being prepared for the job interview," Carroll said.

"And when you think about which candidate to support, you may start to feel confidence in your thoughts about that issue - not realizing that the confidence is actually coming from your preparations for the job interview."

The research was published online recently in the Journal of Experimental Social Psychology.

One of the studies involved 80 college students who were told they were going to be participating in two separate experiments.

First, participants learned about what they were told was a new proposal at their university for funding research on genetically modified foods. (There was actually no such proposal.) The proposal listed major benefits of genetically modified foods, including environmental protection and crop growth.

Half of the participants were told to list three positive thoughts about increasing funding for this research, while the other half listed three negative thoughts.

All the participants were told they would then be taking part in a second study on the role of self-presentation in interpersonal attraction. As part of this, they used a computer to write down what they thought were their greatest strength, greatest weakness and most important life goal.

They were told this profile would be evaluated by an opposite-sex student in the next room who would provide feedback and indicate how much they would like to meet them in person later. (There was actually no such person.)

After participants sent their presentation, they all received a message on their screen very quickly saying that their partner had already made their evaluation.

Half were told on the screen that the early return didn't mean anything as far as their evaluation. But the other half were told that an early return indicated a worse evaluation.

"This warning of a likely negative evaluation allowed participants some time to prepare for it," Carroll said. "The other participants had no reason to prepare."

Afterward, all participants were asked to reflect on their thoughts on the proposal to fund research on genetically modified foods and answered several questions.

Results showed that the students who had to prepare themselves for the bad news in the second experiment reacted differently to their thoughts on the unrelated research funding than those who didn't have to prepare.

If they generated positive thoughts earlier, those who prepared had a more positive attitude toward the research funding than those who didn't prepare. And if they generated negative thoughts, those who prepared had more negative attitudes than those who didn't prepare.

"Preparedness didn't change people's opinions about the research funding. But it did validate the thoughts they already had, whether those thoughts were positive or negative," Carroll said.

"And of course, their feelings of preparedness had nothing to do with the issue of research funding for genetically modified foods."

Participants who had prepared for the bad news also indicated they had more confidence in their thoughts about the research funding proposal, compared to those who didn't prepare.

"Being prepared in one area gave people more confidence in their thoughts in a completely different area, and this helped strengthen their attitudes," he said.

Two other studies confirmed these findings, using different designs and subject matters. While in the study discussed above participants prepared themselves mentally for bad news, in another study, the researchers had participants write down strategies on how to handle different situations posed in the experiment.

"In different studies, we looked at different ways of being prepared," he said. "Ultimately, preparedness is about knowing how to respond to future outcomes."

The findings suggest people should think more closely about how they arrive at important decisions in their lives, Carroll said.

"We sometimes feel like we're leaning in one direction on a decision and then something changes and we feel more convinced about the choice," he said.

"It is worth considering what caused that shift. Your newfound confidence may be coming from somewhere you aren't aware of."

Bots are social media accounts which are controlled by artificial software rather than by humans and serve a variety of purposes from news aggregation to automated customer assistance for online retailers. However, bots have recently been under the spotlight as they are regularly employed as part of large-scale efforts on social media to manipulate public opinion, such as during electoral campaigns.

A new study in Frontiers in Physics has revealed the presence of short-term behavioral trends in humans that are absent in social media bots, providing an example of a 'human signature' on social media which could be leveraged to develop more sophisticated bot detection strategies. The research is the first study of its kind to apply user behavior over a social media session to the problem of bot detection.

"Remarkably, bots continuously improve to mimic more and more of the behavior humans typi-cally exhibit on social media. Every time we identify a characteristic we think is prerogative of human behavior, such as sentiment of topics of interest, we soon discover that newly-developed open-source bots can now capture those aspects," says co-author Emilio Ferrara, As-sistant Professor of Computer Science and Research Team Leader at the University of Southern California Information Sciences Institute.

In this work, the researchers studied how the behavior of humans and bots changed over the course of an activity session using a large Twitter dataset associated with recent political events. Over the course of these sessions, the researchers measured various factors to capture user behavior, including the propensity to engage in social interactions and the amount of pro-duced content, and then compared these results between bots and humans.

To study the behavior of bot and human users over an activity session, the researchers focused on indicators of the quantity and quality of social interactions a user engaged in, including the number of retweets, replies and mentions, as well as the length of the tweet itself. They then leveraged these behavioral results to inform a classification system for bot detection to observe whether the inclusion of features describing the session dynamics could improve the perfor-mance of the detector. A range of machine learning techniques were used to train two differ-ent sets of classifiers: one including the features describing the session dynamics and one with-out those features, as a baseline.

The researchers found, among humans, trends that were not present among bots: Humans showed an increase in the amount of social interaction over the course of a session, illustrated by an increase in the fraction of retweets, replies and number of mentions contained in a tweet. Humans also showed a decrease in the amount of content produced, illustrated by a de-creasing trend in average tweet length. These trends are thought to be due to the fact that as sessions progress, human users grow tired and are less likely to undertake complex activities, such as composing original content. Another possible explanation may be given by the fact that as time goes by, users are exposed to more posts, therefore increasing their probability to react and interact with content. In both cases, bots were shown to not be affected by such consider-ations and no behavioral change was observed from them.

The researchers used these behavioral results to inform a classification system for bot detection and found that the full model including the features describing session dynamics significantly outperformed the baseline model in its accuracy of bot detection, which did not describe those features.

These results highlight that user behavior on social media evolves in a measurably different manner between bots and humans over an activity session and also suggests that these differ-ences can be used to implement a bot detection system or to improve existing ones.

Emilio highlights: "Bots are constantly evolving - with fast paced advancements in AI, it's possi-ble to create ever-increasingly realistic bots that can mimic more and more how we talk and interact in online platforms."

"We are continuously trying to identify dimensions that are particular to the behavior of hu-mans on social media that can in turn be used to develop more sophisticated toolkits to detect bots."

To combat weeds, farmers use a variety of tools and methods. By understanding the strengths and downfalls of each tool, a farmer can make the best decisions for his or her operation to keep pesky weeds out of the field.

One tool farmers can turn to for weed control is applying herbicides. New research is helping us understand a specific herbicide even better: atrazine.

Atrazine is one of the most common herbicides used in the United States. It can be used to manage weeds in crops like corn, sorghum, sugarcane and turf. The chemical kills weeds by preventing photosynthesis in the plant.

A benefit of herbicides, like those with atrazine, is that they reduce the need for tillage. In addition to its effects on soil health, tillage can increase erosion of precious soil. Reducing tillage conserves our soil by preventing erosion and maintaining healthy soil structure.

A downfall of atrazine, though, is that it can sometimes make its way into streams and rivers.

After the chemical is applied to a field, atrazine breaks down in the soil and turns into another compound, called deethylatrazine (DEA). This is a good thing, since DEA is less toxic to aquatic organisms than atrazine.

In recent years, atrazine use has been decreasing. However, despite the decrease in atrazine use, concentrations of the secondary compound, DEA, have been increasing.

Karen Ryberg and her team thought there must be more to this puzzle than just atrazine use.

Ryberg, who works at the United States Geological Survey, wanted to determine the factors, other than usage, that influence trends in herbicide concentrations in streams.

The most common conversion of atrazine to DEA is through the activity of soil microbes - like fungi and bacteria. Therefore, atrazine breaks down quicker when it has more contact with soil microorganisms.

"Based on previous studies, we predicted factors affecting the atrazine concentrations in streams," says Ryberg. "These included that corn acres in the watershed, weather, climate and management practices."

"In our study, we used existing data from 2002 to 2012 spanning many areas of the country," explains Ryberg. Then models were used to analyze the data and test the team's predictions of what caused the atrazine and DEA trends in the streams.

In the 1990s, new regulations addressed surface water contamination concerns. These regulations lowered application rates of atrazine for crops, and even prohibited its use near water wells. The goal was to reduce the overall concentration of atrazine in water.

"Concentration and use trends show that past atrazine regulations, especially in the Midwest, were successful," says Ryberg. "More of the atrazine broke down into DEA before reaching streams."

Despite an increase in the amount of corn acres grown between 2002 and 2012, the study showed atrazine use decreased in most areas of the United States.

Ryberg's study also discovered that atrazine turns into DEA faster in dry areas without tile drainage. Tile drains can be installed underground in farm fields to help move water and prevent flooding. Tile drains are like stormwater drains for farm fields.

Because tile drains help water from the field move faster through underground pipes, the water has less time to come in contact with soil. Therefore, soil microorganisms have less time to break down atrazine to DEA before water carries it out of the field toward nearby streams.

This finding means there may be more challenges with atrazine levels in the future. As farmers anticipate climate change and wetter field conditions, more tile drains may be needed in order to grow crops in adequate soil conditions.

Moving forward, Ryberg would like to build on this research for monitoring pesticides. "Ongoing monitoring is important to understand the degradation and transport processes of pesticides," explains Ryberg.

Farmers will continue to adapt to changing conditions, including weed communities. Pesticide usage will change, and it is an ongoing challenge to monitor for new pesticides or mixtures of pesticides in the environment.

Pancreatic cancer cells use a normal waste removal process to hide tags on their surfaces that would otherwise let the immune system destroy them, a new study finds. Published online April 22 in Nature, the study results help to answer a longstanding question: why are pancreatic cancers so resistant to immunotherapies, which use the body's own immune defenses to fight cancer?

The work focused on the major histocompatibility complex class 1 or MHC-I, a group of proteins that displays certain protein fragments on cell surfaces. T cells of the immune system ignore cells with MHC-I displaying "self" tags specific to each person's cells, but recognize and attack cells with strange tags, like those on cells infected with viruses, and in some cases on cells that have become cancerous.

Led by researchers in the Department of Radiation Oncology at the NYU Grossman School of Medicine, its Perlmutter Cancer Center, and the University of California, San Francisco (UCSF), the new study found that in pancreatic cancer, MHC-I is pulled into compartments called vesicles inside the cancer cells and degraded by autophagy, a normal process that recycles damaged cellular components. By removing the MHC-I tags, autophagy enables cancer cells to avoid notice by the immune system, and makes them resistant to immunotherapies, researchers say.

"Our findings show that blocking autophagy, either genetically or with drugs, enhances the expression of MHC-I on the surface of pancreatic cancer cells," says senior study co-author Alec Kimmelman, MD, PhD, the Anita Steckler and Joseph Steckler Professor and Chair of the Department of Radiation Oncology at NYU Langone Health.

"This newfound role in immune evasion adds to the growing body of evidence that supports the targeting of the autophagy pathway in pancreatic and other cancers," adds Kimmelman, also a senior leader of Perlmutter Cancer Center. Previous studies from Kimmelman's lab, for instance, had found that pancreatic cancer cells also harness autophagy to create a supply of degraded cellular components as fuel for malignant cell growth.

Pancreatic ductal adenocarcinoma (PDAC), the most common form of pancreatic cancer, is among the cancer types for which immunotherapy using drugs called checkpoint inhibitors has been largely ineffective. Although the reasons that such therapies fail against some cancers is complicated, genetic changes (mutations) that lead to a loss of MHC-I on tumor cell surfaces have been hypothesized as one cause, says Kimmelman. PDAC tumors, however, do not have these mutations, suggesting that other mechanisms are at work.

Kimmelman and senior study co-author Rushika Perera, PhD, at UCSF independently determined that a significant fraction of MHC-I no longer resided on the surfaces of pancreatic cancer cells, but instead was found inside the cells. The two labs then collaborated to show that an autophagy protein, called NBR1, attaches to MHC-I, which sets it up to be trafficked to autophagosomes and then lysosomes, where it is broken down like cellular waste.

Experiments in mice with pancreatic cancer showed that blocking autophagy either with genetic approaches or with the anti-malaria drug chloroquine caused an increase in MHC-I molecules on the surfaces of the tumor cells. Chloroquine and its derivative hydroxychloroquine, the latter of which is being tested as a possible treatment against the COVID-19 pandemic virus, are known to inhibit autophagy by the same mechanism. The authors also found in mouse studies that combined chloroquine with two checkpoint inhibitors significantly increased tumor response over that achieved by the immunotherapies alone.

The researchers also studied tumor cell lines from non-small cell lung cancers and found that MHC-I is also targeted for degradation by autophagy in a fraction of these tumors. The finding suggests that resistance to immunotherapy due to internalization of MHC-I seen in pancreatic cancer cells could be at work in other cancer types.

Clinical trials in patients with pancreatic cancer have shown that hydroxychloroquine, combined with standard chemotherapy, increases a patient's response to chemotherapy. The new findings that suggest hydroxychloroquine could also improve the effectiveness of immunotherapy. While promising, such combinations need to be studied further before they can be tested clinically, Kimmelman cautions.

"The next step in our work will be to begin studies that seek to translate these findings to patients," says co-lead study author Keisuke Yamamoto, MD, PHD, a postdoctoral research fellow in Kimmelman's lab. "Our goals are to understand how to sequence chemotherapy with hydroxychloroquine and immunotherapies, as well as to identify markers for subgroups of patients that are more likely to respond."

Hunter-gatherer groups living in the Baltic between seven and a half and six thousand years ago had culturally distinct cuisines, analysis of ancient pottery fragments has revealed.

An international team of researchers analysed over 500 hunter-gatherer vessels from 61 archaeological sites throughout the Baltic region.

They found striking contrasts in food preferences and culinary practices between different groups - even in areas where there was a similar availability of resources. Pots were used for storing and preparing foods ranging from marine fish, seal and beaver to wild boar, bear, deer, freshwater fish hazelnuts and plants.

The findings suggest that the culinary tastes of ancient people were not solely dictated by the foods available in a particular area, but also influenced by the traditions and habits of cultural groups, the authors of the study say.

A lead author of the study, Dr Harry Robson from the Department of Archaeology at the University of York, said: "People are often surprised to learn that hunter-gatherers used pottery to store, process and cook food, as carrying cumbersome ceramic vessels seems inconsistent with a nomadic life-style.

"Our study looked at how this pottery was used and found evidence of a rich variety of foods and culinary traditions in different hunter-gatherer groups."

The researchers also identified unexpected evidence of dairy products in some of the pottery vessels, suggesting that some hunter-gatherer groups were interacting with early farmers to obtain this resource.

Dr Robson added: "The presence of dairy fats in several hunter-gatherer vessels was an unexpected example of culinary 'cultural fusion'. The discovery has implications for our understanding of the transition from hunter-gatherer lifestyles to early farming and demonstrates that this commodity was either exchanged or perhaps even looted from nearby farmers."

Lead author of the study, Dr Blandine Courel from the British Museum, added: "Despite a common biota that provided lots of marine and terrestrial resources for their livelihoods, hunter-gatherer communities around the Baltic Sea basin did not use pottery for the same purpose.

"Our study suggests that culinary practices were not influenced by environmental constraints but rather were likely embedded in some long-standing culinary traditions and cultural habits."

The study, led by the Department of Scientific Research at the British Museum, the University of York and the Centre for Baltic and Scandinavian Archaeology (Stiftung Schleswig-Holsteinische Landesmuseen, Germany), used molecular and isotopic techniques to analyse the fragments of pottery.

Senior author, Professor Oliver Craig from the Department of Archaeology at the University of York, said: "Chemical analysis of the remains of foods and natural products prepared in pottery has already revolutionized our understanding of early agricultural societies, we are now seeing these methods being rolled out to study prehistoric hunter-gatherer pottery. The results suggest that they too had complex and culturally distinct cuisines."

Organic residue analysis shows sub-regional patterns in the use of pottery by Northern European hunter-gatherers is published in Royal Society Open Science. The research was funded by the European Research Council through a grant awarded to the British Museum.

Capping decades of research, a new study may offer a breakthrough in treating dyskeratosis congenita and other so-called telomere diseases, in which cells age prematurely. Using cells donated by patients with the disease, researchers at the Dana-Farber/Boston Children's Cancer and Blood Disorders Center identified several small molecules that appear to reverse this cellular aging process. Suneet Agarwal, MD, PhD, the study's senior investigator, hopes at least one of these compounds will advance toward clinical trials. Findings were published April 21 in the journal Cell Stem Cell.

If so, it could be the first treatment for dyskeratosis congenita, or DC, that could reverse all of the disease's varying effects on the body. The current treatment, bone marrow transplant, is high-risk, and only helps restore the blood system, whereas DC affects multiple organs.

Telomeres, telomerase, and health

The compounds identified in the study restore telomeres, protective caps on the tips of our chromosomes that regulate how our cells age. Telomeres consist of repeating sequences of DNA that get shorter each time a cell divides.

The body's stem cells, which retain their youthful qualities, normally make an enzyme called telomerase that builds telomeres back up again. But when telomeres can't be maintained, tissues age before their time. A spectrum of diseases can result -- not just DC, but also aplastic anemia, liver cirrhosis, and pulmonary fibrosis.

The discovery of telomerase 35 years ago, earning a Nobel Prize in 2009, galvanized the scientific world. Subsequent studies suggested the enzyme could be a key to reversing aging, as well as treating cancer, in which malignant cells become "immortal" and divide indefinitely.

For years, researchers have tried to find a simple and safe way to manipulate telomerase, preserve telomeres, and create cures for telomere diseases.

"Once human telomerase was identified, there were lots of biotech startups, lots of investment," says Agarwal, who has researched the biology of telomerase for the past decade. "But it didn't pan out. There are no drugs on the market, and companies have come and gone."

Finding a small molecule for telomere diseases

DC can be caused by mutations in any of multiple genes. Most of these mutations disrupt telomerase formation or function -- in particular, by disrupting two molecules called TERT and TERC that join together to form telomerase. TERT is an enzyme made in stem cells, and TERC is a so-called non-coding RNA that acts as a template to create telomeres' repeating DNA sequences. Both TERT and TERC are affected by a web of other genes that tune telomerase's action.

One of these genes is PARN. In 2015, Agarwal and colleagues showed in Nature Genetics that PARN is important for processing and stabilizing TERC. Mutations in PARN mean less TERC, less telomerase, and prematurely shortened telomeres.

The new study, led by postdoctoral fellow Neha Nagpal, PhD, delved further, focusing on an enzyme that opposes PARN and destabilizes TERC, called PAPD5.

"We thought if we targeted PAPD5, we could protect TERC and restore the proper balance of telomerase," says Nagpal, first author on the paper.

Nagpal and her colleagues first conducted large-scale screening studies to identify PAPD5 inhibitors, testing more than 100,000 known chemicals. They got 480 initial "hits," which they ultimately narrowed to a small handful.

They then tested the inhibitors in stem cells made from the Martins' cells and those of other patients with DC. To the team's delight, the compounds boosted TERC levels in the cells and restored telomeres to their normal length.

But the real challenge was to see if the treatment would be safe and specific, affecting only the stem cells bearing TERT. To test this, the team introduced DC-causing PARN mutations into human blood stem cells, transplanted those cells into mice, then treated the mice with oral PAPD5 inhibitors. The compounds boosted TERC and restored telomere length in the transplanted stem cells, with no adverse effect on the mice or on the ability to form different kinds of blood cells.

"This provided the hope that this could become a clinical treatment," says Nagpal.

The road ahead

In the future, Agarwal, Nagpal, and colleagues hope to validate PAPD5 inhibition for other diseases involving faulty maintenance of telomeres -- and perhaps even aging itself. They are most excited about two compounds, known as BCH001 and RG7834 that are under further development.

"We envision these to be a new class of oral medicines that target stem cells throughout the body," Agarwal says. "We expect restoring telomeres in stem cells will increase tissue regenerative capacity in the blood, lungs, and other organs affected in DC and other diseases."

Unlike animals, which only digest proteins, carbohydrates and fats, microorganisms also feed on a variety of other organic compounds. Even natural gas does not stop them. Researchers from Bremen have now discovered a microbe in the deep sea that eats ethane, which, with a share of up to 15%, is the second most common component of natural gas.

Life in the extreme

The research group led by Gunter Wegener from the Max Planck Institute for Marine Microbiology, in cooperation with researchers from other institutes, discovered the previously unknown microbe in the seafloor of the Guaymas Basin at a water depth of 2000 meters in the Gulf of California. "The Guaymas Basin is a natural laboratory teeming with new species," Wegener said. "Responsible for this extraordinary diversity are hot fluids gushing out of the seafloor, which attract many different species. Already today, we have discovered many organisms in this habitat."

Degrading natural gas in teamwork

Some natural gas components such as propane or butane can be broken down by bacteria alone. However, in order to degrade the main components of natural gas - methane and ethane - two different organisms are necessary according to the present state of research, which form a so-called consortium: Archaea, which break down the natural gas, and bacteria, which couple the electrons released in the process to sulfate, an abundant compound in the ocean. Studying the biochemical processes in the consortia in the laboratory has been extremely challenging up to now: These organisms grow very slowly and only divide every few months. Thus, there was always little biomass available.

First time in laboratory culture

This is different with the ethane producers that have now been discovered: "These consortia are growing much faster," reported Cedric Hahn, PhD student at the Max Planck Institute for Marine Microbiology and first author of the study. The cells double every week. "The laboratory cultures keep me pretty busy. But this way we now have enough biomass for extensive analyses. For example, we were able to identify key intercellular intermediates in ethane degradation. Also, we present the first complete genome of a natural gas-degrading archaea in this study."

The newly discovered archaea was named Ethanoperedens thermophilum, which means "heat-loving ethane-eater". Its partner bacteria are familiar from other consortia. Katrin Knittel, who has been working on the topic since the discovery of the first methane-munching consortia, said: "We have found gene sequences of these archaea at many deep-sea vents. Now we finally understand their function."

Archaea could also convert carbon dioxide into ethane

The researchers also discovered something else: The ethane degradation of this microbe is reversible. Thus, relatives of Ethanoperedens could produce ethane from carbon dioxide. This is highly interesting for biotechnological applications. Wegener's team is now searching for such organisms. In addition, in cooperation with colleagues, they aim to convert microbes that produce methane into ethane producers. "We are not yet ready to understand all the steps involved in ethane degradation," said Rafael Laso Pérez, who did his doctoral thesis on butane gas-degrading archaea. "We are currently investigating how Ethanoperedens can work so efficiently. If we understand its tricks, we could culture new archaea in the lab that could be used to obtain resources that currently have to be extracted from natural gas."

This way, the microbes described here are significant for the global carbon cycle and the rising atmospheric carbon dioxide concentration in two ways: On the one hand, they use ethane in the deep sea and thus prevent this gas from reaching the atmosphere. On the other hand, they could offer a solution for the industry to reduce its carbon emissions. "This is still a long way off," Wegener said. "But we are pursuing our research. One thing we know for sure: We shouldn't underestimate the smallest inhabitants of the sea!"

While energy sources such as wind and solar are great at producing emissions-free electricity, they depend on the sun and the wind, so supply doesn't always meet the demand. Likewise, nuclear power plants operate more efficiently at maximum capacity so that electricity generation can't be easily ramped up or down to match demand.

For decades, energy researchers have tried to solve one big challenge: How do you store excess electricity so it can be released back onto the grid when it's needed?

Recently, researchers at Idaho National Laboratory helped answer that challenge by developing a new electrode material for an electrochemical cell that can efficiently convert excess electricity and water into hydrogen. When demand for electricity increases, the electrochemical cell is reversible, converting hydrogen back into electricity for the grid. The hydrogen could also be used as fuel for heat, vehicles or other applications.

The results appeared online this week in the journal Nature Communications.

Researchers have long recognized the potential of hydrogen as an energy storage medium, said Dong Ding, a senior staff engineer/scientist and chemical processing group lead at INL.

"The energy storage grand challenge, with its diverse research and development needs, gave rise to more opportunities for hydrogen," said Ding. "We are targeting hydrogen as the energy intermediate to efficiently store energy."

Ding and his colleagues improved one type of electrochemical cell called a protonic ceramic electrochemical cell (PCEC), which uses electricity to split steam into hydrogen and oxygen.

However, in the past, these devices had limitations, especially the fact that they operate at temperatures as high as 800 degrees C. The high temperatures require expensive materials and result in faster degradation, making the electrochemical cells cost prohibitive.

In the paper, Ding and colleagues describe a new material for the oxygen electrode--the conductor that facilitates the water splitting and oxygen reduction reactions simultaneously. Unlike most electrochemical cells, this new material--an oxide of a compound called a perovskite--allows the cell to convert hydrogen and oxygen into electricity without additional hydrogen.

Previously, Ding and his colleagues developed a 3D meshlike architecture for the electrode that made more surface area available to split the water into hydrogen and oxygen. Together, the two technologies--the 3D mesh electrode and the new electrode material--allowed for self-sustainable, reversible operation at 400 to 600 degrees C.

"We demonstrated the feasibility of reversible operation of the PCEC at such low temperatures to convert generated hydrogen in hydrolysis mode to electricity, without any external hydrogen supply, in a self-sustaining operation," Ding said. "It's a big step for high temperature electrolysis."

While past oxygen electrodes conducted only electrons and oxygen ions, the new perovskite is "triple conducting," Ding said, meaning it conducts electrons, oxygen ions and protons. In practical terms, the triple-conducting electrode means the reaction happens faster and more efficiently, so the operating temperature can be reduced while maintaining good performance.

For Ding and his colleagues, the trick was figuring out how to add the element to the perovskite electrode material that would give it the triple-conducting properties--a process called doping. "We successfully demonstrated an effective doping strategy to develop a good triple-conducting oxide, which enables good cell performance at reduced temperatures," said Hanping Ding, a materials scientist and engineer for Idaho National Laboratory's Chemical Processing Group.

In the future, Dong Ding and his colleagues hope to continue improving the electrochemical cell by combining materials innovation with cutting-edge manufacturing processes so the technology can be used at an industrial scale.

PULLMAN, Wash. - During this pandemic when few parents can limit screen time, a new study shows that building critical media skills as a family can have a positive impact on kids' nutrition without restricting their access to TV and computers.

The study, published in the journal Childhood Obesity on April 20, found that an education program that had parents and kids learn media literacy skills together not only helped children eat more fruits and vegetables but also improved communication between parents and their kids.

"We weren't trying just to get children to stop nagging their parents for things like candy and chips," said Erica Weintraub Austin, lead author on the study and director of the Edward R. Murrow Center for Media and Health Promotion Research at Washington State University. "We wanted them to be working together to make healthy decisions, and for the children to be well positioned for the future when they have to make those decisions on their own."

The study tested the impact of a community program called FoodMania! with nearly 200 sets of parents and their children ages 9 to 14, who came from three urban and two rural counties in Washington state. Over the course of the six-unit education program, parents and kids learned about good nutrition and worked together to uncover the methods and intent behind food advertising. The program's goal is to help families recognize marketing techniques, so they can make food choices based on real information instead of being manipulated, Austin said.

Pre- and post-tests were compared between parent and child sets who participated in the media literacy program through WSU Extension offices and a control group that did not. Austin and her colleagues found that among the participants: the parents improved their use of nutrition labels, they had a better ratio of healthy to unhealthy foods in their home, and the children reported eating more fruits and vegetables.

The biggest effect, however, was in family communication around food both with parents teaching kids critical thinking about media messages and children initiating conversations with their parents on the topic.

"Managing food and media together seemed to create opportunities for an overall supportive communication environment in the family," Austin said. "Children really like to know that their views are valued. It is really motivating for them when they can find out about something on their own instead of being lectured to."

While media use has been linked to obesity in children, the study purposely concentrated on promoting media literacy, rather than restricting media. Austin said limiting screen time is difficult and does not solve the problem because children are surrounded by food marketing.

"From the time they are infants, children are marketed to," Austin said.

Developmentally, children lack many of the critical skills of adults. First, they have to understand the difference between a program and an advertisement, and then at another level to realize there's a persuasive intent behind an advertisement that is not necessarily for their benefit - a realization, Austin said, that is not often fully developed until the preteen years.

"Executive function skills grow as the child grows, including their ability to control their own behavior and responses," Austin said. "But these are things we can help them practice."

This summer, NASA plans to launch its next Mars rover, Perseverance, which will carry with it the first aircraft to ever fly on another planet, the Mars Helicopter. As the first of its kind, the Mars Helicopter will carry no instruments and collect no data -- NASA describes merely flying it all as "high-risk, high-reward" research.

With the risks of extraterrestrial flight in mind, Penn Engineers are suggesting a different approach to exploring the skies of other worlds: a fleet of tiny aircraft that each weigh about as much as a fruit fly and have no moving parts.

These flyers are plates of "nanocardboard," which levitate when bright light is shone on them. As one side of the plate heats up, the temperature differential gets air circulating through its hollow structure and shooting out of the corrugated channels that give it its name, thrusting it off the ground.

A recently published study demonstrates nanocardboard's flying and payload-carrying abilities in an environment similar to that of Mars. The thinner atmosphere there would give the flyers a boost, enabling them to carry payloads ten times as massive as they are. The weaker Martian gravity would further enhance their capabilities.

The study, published in the journal Advanced Materials, was led by Igor Bargatin, Class of 1965 Term Assistant Professor in the Department of Mechanical Engineering and Applied Mechanics (MEAM), and John Cortes, then a graduate student in his lab. Fellow lab members, Christopher Stanczak, Mohsen Azadi, Maanav Narula, Samuel M. Nicaise and MEAM Professor and master's program chair Howard Hu also contributed to the study.

"The Mars Helicopter is very exciting, but it's still a single, complicated machine," Bargatin says. "If anything goes wrong, your experiment is over, since there's no way of fixing it. We're proposing an entirely different approach that doesn't put all of your eggs in one basket."

Bargatin's group has been experimenting and improving on their nanocardboard design since 2017. Inspired by the common paper packaging material, they collaborated with researchers at the Singh Center for Nanotechnology to achieve a record-setting ratio of weight and stiffness, as reported in a recent Nature Communications paper.

Like paper cardboard and other "sandwich structured composites" used in architecture and aviation, nanocardboard's material properties stem from corrugation. Consisting of a hollow plate of aluminum oxide walls that are only a few nanometers thick, that corrugation is a regular pattern of channels spanning the plate, which enhance its bending stiffness and prevent cracks from propagating.

These channels are also responsible for the plates' ability to levitate, as creating a temperature differential generates an air current that flows through their hollow structure.

"The air current through these micro-channels is caused by a classical phenomenon called 'thermal creep,'" says Hu, "which is a rarefied gas flow due to the temperature gradient along the channel wall."

Their recent study allowed the researchers to measure the flyers' ability to lift mock payloads -- silicone rings, attached to the top of the plates -- thanks to a new low-pressure test chamber with integrated cameras and light sources.

Studying these dynamics are important for vetting nanocardboard's potential as a material for atmospheric probes, especially on other worlds, including Mars, Pluto and Neptune's moon Triton. Because Bargatin's nanocardboard flyers weigh about a third of a milligram, it would take more than a million of them to equal the mass of the Mars Helicopter, and more than six billion to equal the ground-based rover that will deploy it.

But even in the ideal environment of the Martian atmosphere, the tiny flyers would still be limited to sensors and payloads that are at most a few milligrams. As such, Bargatin is now collaborating with other researchers on how to miniaturize chemical sensors that could detect water or methane -- key signatures of life on Mars.

"In addition to carrying sensors," Bargatin says, "our flyers could simply land and have grains of dust or sand passively stick to them, then transport them back to the rover so it doesn't need to travel as far."

The rover could also provide a means of piloting the nanocardboard flyers. Despite having no moving parts, they can be steered by way of a pinpoint laser, since the direction of the air flowing out of their channels depends on which parts of the plate are heated.

Terrestrial applications are also possible.

"The Earth's mesosphere is pretty similar to the Martian atmosphere in terms of density, and we currently don't have anything that flies there, since it is too low for space satellites but too high for airplanes and balloons," Bargatin says. "Ideally, you'd like to have some sensors up there as well. The more knowledge you have about the movement of the atmosphere at that level, the better predictions you can make about Earth's climate and even weather."

Can staying up late make you fat? A growing body of research has suggested that poor sleep quality is linked to an increased risk of obesity by deregulating appetite, which in turn leads to more calorie consumption.

But a new study published this week in PLOS Biology found that the direction of this reaction might actually be flipped: It's not the sleep loss that leads to obesity, but rather that excess weight can cause poor sleep, according to researchers from the University of Pennsylvania's Perelman School of Medicine and the University of Nevada, Reno, who discovered their findings in the microscopic worm Caenorhabditis elegans (C. elegans).

"We think that sleep is a function of the body trying to conserve energy in a setting where energetic levels are going down. Our findings suggest that if you were to fast for a day, we would predict you might get sleepy because your energetic stores would be depleted," said study co-author David Raizen, MD, PhD, an associate professor of Neurology and member of the Chronobiology and Sleep Institute at Penn.

Raizen emphasized that while these findings in worms may not translate directly to humans, C. elegans offer a surprisingly good model for studying mammalian slumber. Like all other animals that have nervous systems, they need sleep. But unlike humans, who have complex neural circuitry and are difficult to study, a C. elegans has only 302 neurons -- one of which scientists know for certain is a sleep regulator.

In humans, acute sleep disruption can result in increased appetite and insulin resistance, and people who chronically get fewer than six hours of sleep per night are more likely be obese and diabetic. Moreover, starvation in humans, rats, fruit flies, and worms has been shown to affect sleep, indicating that it is regulated, at least in part, by nutrient availability. However, the ways in which sleeping and eating work in tandem has remained unclear.

"We wanted to know, what is sleep actually doing? Short sleep and other chronic conditions, like diabetes, are linked, but it's just an association. It's not clear if short sleep is causing the propensity for obesity, or that the obesity, perhaps, causes the propensity for short sleep," said study co-author Alexander van der Linden, PhD, an associate professor of Biology at the University of Nevada, Reno.

To study the association between metabolism and sleep, the researchers genetically modified C. elegans to "turn off" a neuron that controls sleep. These worms could still eat, breathe, and reproduce, but they lost their ability to sleep. With this neuron turned off, the researchers saw a severe drop in adenosine triphosphate (ATP) levels, which is the body's energy currency.

"That suggests that sleep is an attempt to conserve energy; it's not actually causing the loss of energy," Raizen explained.

In previous research, the van der Linden lab studied a gene in C. elegans called KIN-29. This gene is homologous to the Salt-Inducible Kinase (SIK-3) gene in humans, which was already known to signal sleep pressure. Surprisingly, when the researchers knocked out the KIN-29 gene to create sleepless worms, the mutant C. elegans accumulated excess fat -- resembling the human obesity condition -- even though their ATP levels lowered.

The researchers hypothesized that the release of fat stores is a mechanism for which sleep is promoted, and that the reason KIN-29 mutants did not sleep is because they were unable to liberate their fat. To test this hypothesis, the researchers again manipulated the KIN-29 mutant worms, this time expressing an enzyme that "freed" their fat. With that manipulation, the worms were again able to sleep.

Raizen said this could explain one reason why people with obesity may experience sleep problems. "There could be a signaling problem between the fat stores and the brain cells that control sleep," he said.

While there is still much to unravel about sleep, Raizen said that this paper takes the research community one step closer to understanding one of its core functions -- and how to treat common sleep disorders.

"There is a common, over-arching sentiment in the sleep field that sleep is all about the brain, or the nerve cells, and our work suggests that this isn't necessarily true," he said. "There is some complex interaction between the brain and the rest of the body that connects to sleep regulation."

Researchers from Michigan State University released a study on "sextortion" - a lesser-known internet crime that poses a threat to adults and minors - that sheds light on the importance of protecting the public from online criminals.

"Sextortion is the use of intimate images or videos that have been captured to then extort compliance from a victim," said Roberta Liggett O'Malley, MSU criminal justice doctoral student and co-author of the study. "What makes it different from any other crime is the threat to release. A perpetrator could say, 'I have these images of you and will publish them unless you...' to get more images or even in exchange for money."

In many cases of sextortion, perpetrators don't actually possess the images or videos they're using as leverage. Instead, offenders manipulate victim behavior by tapping into the fear of not knowing whether the threat is real.

The research -- published in Journal of Interpersonal Violence -- suggests the current focus on dissemination of images online may overshadow the issue of threat-based harassment online, like sextortion. While most U.S. states have laws against revenge porn, the study makes a case for increasing awareness and changing legislation to include other forms of internet-based sexual abuse crimes.

"Much of the fear comes from the belief that hackers can do anything involving technology, from the ability to see someone's web browser history to hacking into a webcam or Nest device," said Karen Holt, assistant professor of criminal justice and co-author. "That's why sextortion is so effective -- it creates a huge amount of uncertainty and fear that victims end up complying versus saying, 'I think you're bluffing, and if I ignore you, then I'm fine.'"

Liggett O'Malley and Holt said men are less likely to report these crimes to police out of embarrassment or shame, but also don't experience the longevity of harassment experienced by minors.

"The victims are overwhelmingly minors and females, but if the objective is to get money, they're almost always targeting men," Liggett O'Malley said. "These two groups of people experience a similar crime in very different ways."

Analysis of 152 cyber sextortion offenders uncovered four distinct types: minor-focused, targeting victims under 18 years of age; cybercrime, targeting victims using computer-based tactics like hacking; intimately violent, targeting former or current romantic partners; and transnational, targeting strangers strictly for financial reasons.

Holt explained that the four themes reflect different motivations for what offenders want from their victims. A survey of 1,631 cyber sextortion victims found 46% were minors, making crimes against minors a focus for law enforcement and in research literature.

"The disproportionate focus on minor victims has led to new laws that protect minors from adult sexual solicitation online, but there are few legal protections for adult male and female victims," Liggett O'Malley said.

Researchers are starting to see sextortion being used by a lot of other perpetrators. Within a domestic violence context, partners may share images consensually, only to have those images later used as leverage in the relationship. In other instances, transnational organizations employ scams in which individuals pretend to be a man or women on the internet, engaging in webcam sessions with victims and immediately threatening to release a recording unless money is provided.

Awareness and reporting of sextortion crimes, while acting responsibly online, are key in protecting adults and children.

"As digital citizens, we have to start advocating for more accountability on behalf of platforms to take these images down, or to report harassment," Holt said. "A lot of offline crimes have an online component, and oftentimes law enforcement and our behavior don't catch up. We need to think about our own personal safety, both offline and online."

Researchers like Liggett O'Malley and Holt also advocate for federal laws to address the legal loopholes of sextortion.

"We can't only be focused on revenge porn," Liggett O'Malley said. "We need to stop and think about all the ways in which images are used against people and to think about the way we construct these laws to ensure there are pathways for prosecution and arrest."