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What The Study Did: Differences by sex and race/ethnicity in suicidal thoughts and nonfatal suicide attempts among U.S. adolescents over the last three decades were assessed in this survey study.

Authors: Yunyu Xiao, Ph.D., of Indiana University-Purdue University in Indianapolis, is the corresponding author.

To access the embargoed study: Visit our For The Media website at this link https://media.jamanetwork.com/

(doi:10.1001/jamanetworkopen.2021.13513)

Editor's Note: The article includes conflicts of interest disclosures. Please see the article for additional information, including other authors, author contributions and affiliations, conflict of interest and financial disclosures, and funding and support.

PULLMAN, Wash. - Most consumers care about the technology and the ingredients used to make their microwavable dinners and other shelf ready meals, according to a new study led by Washington State University researchers. The study found that many consumers are willing to pay a premium for ready-to-eat meals with a 'clean label' showing few ingredients.

They are also more willing to fork out their hard-earned cash when they know their processed foods are made with a new technology that helps limit the number of additives and preservatives commonly found in most ready-to-eat meals.

"Our findings emphasize the importance of providing consumers information about a new food technology and the resulting benefits," said Karina Gallardo, a WSU professor of economics and corresponding author of the study in the journal Agribusiness. "As foods with 'clean labels,' that is foods with few ingredients, become more popular, these types of technologies will also become more valuable to food manufacturers."

For the study, Gallardo, fellow WSU economist Jill McCluskey, and Kara Grant, an economist at Missouri Western University, conducted a survey and choice experiments to estimate how much consumers value foods with clean labels, which typically include only a handful of ingredients and no additives or preservatives. They surveyed another group of study participants on whether or not a clean label that included the name of a new technology used to make their potential purchase affected their valuation.

"Shelf-ready meals that warrant a clean label have been historically difficult to produce with conventional food preservation technology but recent breakthroughs are making it possible," McCluskey said. "However, because consumers are often wary of adopting new technologies, especially when it comes to the food they eat, it is important to consider their perception of the costs and benefits."

The technology the study participants were asked about is called Microwave Assisted Thermal Sterilization or MATS. Developed by WSU food scientist and Regents Professor Juming Tang, MATS works like a microwave oven, using heat to kill pathogenic bacteria, which ensures both food safety and preserves the taste, texture and appearance of processed meals.

"The MATS technology allows companies to sterilize food products in a way that retains their organolepticqualities, making them more similar to a recently prepared meal," McCluskey said.

It also enables using fewer food preservatives and additives compared to current sterilization practices, she added, which makes it possible to have an end product with the difficult-to-achieve clean label.

Overall, 56% of the study respondents who were asked if they preferred foods that bore both a clean label and the name of the new technology exhibited positive reactions.

One of the reasons the researchers think their study participants preferred the new technology is its name.

"It is based on and named after a massively adopted technology, the microwave," McCluskey said. "The fact that the new technology uses the familiar term microwave is likely a factor that increases its acceptance by consumers."

While both groups of participants exhibited an overall preference for clean labels, there was a large minority of people in the study who weren't interested in paying the price premium for the product with fewer ingredients. Around 39% of respondents in the survey group that was asked solely about clean labels and not the new technology exhibited a negative reaction. These participants tended to have lower than a $67,000 annual income, have children in the household and perceived themselves to be less healthy.

"This group does not consider the message 'absence of artificial ingredients' as important in the labels but does consider a gluten free label as being important," Gallardo said. "It really illustrates the fact that the decision of which foods to buy and consume is very complex."

Alzheimer's disease is the most common form of dementia and is characterized by neurodegeneration in regions of the brain involved in memory and learning. Amyloid beta and tau are two toxic proteins that build up in disease and cause eventual neuronal death, but little is known about how other cells in the brain react during disease progression.

A new study from the ASU-Banner Neurodegenerative Research Center (NDRC) and MIT/Koch Institute sheds new light on how disease processes manifest in patients with Alzheimer's disease.

Diego Mastroeni of the NDRC teamed up Forest White and Douglas Lauffenburger, colleagues in MIT's Department of Biological Engineering, to explore how protein and signaling pathways change in patients with Alzheimer's disease. Their analysis captures a detailed molecular profile of changes in protein levels and alterations known as protein phosphorylation across a cohort of patients with well-preserved brain tissue, from the Banner Sun Health Research Institute. Their work creates a new model of disease progression, taking advantage of the heterogeneity that is inherent to human studies.

"This manuscript highlights the importance of integrating the phosphoproteome with the proteome and transcriptome datasets to get a better picture of the drivers of disease, from transcription to translation," said Mastroeni. (The phosphoproteome refers to proteins that have undergone epigenetic modification through the addition of a phosphate group. The proteome incudes the full complement of all proteins in the body, while the transcriptome refers to the RNA messages produced by genes, which are subsequently translated into proteins.)

The researchers' analysis highlights the links between toxic protein build-up, neurodegeneration, and the glial cells which support and protect neurons in the brain. In particular, they found an intriguing association between markers of neurodegeneration and two types of glial cell: oligodendrocytes and microglia. Progressive alterations in these cells may be key to understanding the causes of neurodegeneration.

The new study appears in the journal Nature Aging.

"Our results show that there are a plethora of cellular signaling pathways that are activated at all stages of disease. We may be able to repurpose available therapies to target protein kinases that regulate these cell signaling events," White says. "Clinicians today are studying therapeutic effects on amyloid and tau as proxies for disease, but our results suggest that glia cells are involved at every step of the process. Improved understanding of glia cells and their roles in progressive neurodegeneration may provide new opportunities for treatment of this disease."

"This collaborative effort is the kind of work that we at the NDRC value," Mastroeni says. "No one individual can tackle this disease on their own; it's going to take a group effort to combat this devastating illness."

Artemisone is a promising substance in the fight against malaria. However, the active ingredient has yet to be used due its instability and because it is not easily absorbed by the body. A team from Martin Luther University Halle-Wittenberg (MLU) and the Hebrew University of Jerusalem has now pushed this a bit further. They have developed a very simple method for preparing the active ingredient that makes it easier to administer and store. The researchers report on their work in the scientific journal "Antimicrobial Agents and Chemotherapy".

Malaria is caused by single-celled parasites (plasmodia) and is one of the most widespread infectious diseases in the world. According to estimates by the World Health Organisation (WHO), there were around 229 million cases of the disease worldwide in 2019, and 409,000 people died. Africa is the most severely affected region.

Laboratory tests have already shown artemisone's efficacy in combating the harmful parasites; however, it has not yet been put to use. "The substance is too unstable and cannot be easily absorbed by the body. Previous formulations have proven very costly to produce," says Professor Karsten Mäder, head of the Pharmaceutical Technology Group at MLU. His research group specialises in the design and production of drug carrier systems. It aims to prepare active ingredients is such a way that optimises various properties, for instance efficacy, absorption in the human body, and stability of the substance. "We have developed a new formulation of artemisone in which the active ingredient is mixed with other substances. This is a very simple process that leads to a much more stable form. The process can be conducted in ordinary laboratories or factories," says Mäder.

The new substance was tested against severe malaria on an animal model at the Hebrew University. It was well absorbed by the body and was able to successfully fight off the parasites. A smaller amount than previous formulations was needed, which comes with an advantage: a lower dose means fewer side effects can be expected.

In an earlier study, the team was also able to show that the new formulation of the drug is also very effective in treating schistosomiasis, a disease caused by flatworms. This disease is also widespread in the tropics.

Extensive clinical trials must be carried out before the active ingredient can be used as a medicine in humans. To this end, Mäder is in talks with several organisations that are committed to improving medical care in Africa.

Niigata, Japan - In the recent past, there has been a paradigm shift towards renewable sources of energy in order to address the concerns pertaining to environmental degradation and dwindling fossil fuels. A variety of alternative green energy sources such as solar, wind, hydrothermal, tidal etc., have been gaining attention to reduce the global carbon footprints. One of the key challenges with these energy generation technologies is that they are intermittent and are not continuously available.

"We cannot use solar energy at night and wind energy when the wind is not blowing. But we can store the generated electricity in some other forms and utilize it whenever required. That is how water splitting bridges the gap and has emerged as a very promising energy storage technology", said Professor Masayuki Yagi who conducts research on energy storage materials and technology at the Department of Materials Science and Technology, Faculty of Engineering/Graduate School of Science and Technology, Niigata University. Water splitting is one of the promising energy storage solutions which would potentially drive the world towards a hydrogen fuelled economy.

The water dissociation process, alternatively known as artificial photosynthesis, traditionally employs electricity to split the water molecule through two half reactions in an electrochemical cell. The hydrogen evolution reaction occurs at the cathode where hydrogen fuel is generated and the water oxidation occurs at the anode where breathable oxygen is released. Although water is a simple molecule that is constituted by only three atoms, the process of dissociating it is quite intense and challenging.

The initial energy, known in scientific terms as the overpotential, plays a crucial role in influencing the progress of the reaction. For the materials explored so far, the initial energy required to trigger the hydrogen evolution at the cathode and oxygen evolution at the anode is so high that the process escalates the overall cost of the reaction, thereby, adversely affecting its commercial utilization. This is particularly a major concern at the anode because the oxygen evolution reaction involves the transfer of four electrons which demands a higher initial energy as compared to the reaction at the cathode.

Prof. Yagi's research team at the Niigata University in association with research collaborators at the Yamagata University are investigating on the electrocatalytic water splitting and to address the key shortcomings. They have been successful in developing an efficient water dissociation process using nickel based nano-compounds as anodes which has been published in as a scientific article in Energy & Environmental Science on 20th May.

In this study, Prof. Yagi's team have observed that the nickel sulphide nanowires based anode has supported the reduction of initial energy that is required for the oxygen evolution reaction. "We have fabricated the anode using a unique motif of nickel sulfide nanowires stuffed into carbon nitride scabbards. The carbon nitride scabbards prevent the core region of NiSx rods from transforming to their oxide, thereby protecting them from further degradation. On the surface of the nickel sulphide nanowires, a thin oxide film is formed due to the contact with the electrolyte solution, which facilitates the oxygen evolution reaction" explained Prof. Yagi.

The research team has observed with the aid of advanced microscopy techniques and electrochemical measurements that the fabricated anode aids in reducing the initial energy, which accelerates the four-electron transfer process in the oxygen evolution reaction. The research finding of Prof. Yagi's team has immense potential in improving the long-term performance and stability of the electrochemical cell.

This research study is an important milestone towards improving the efficiency of the water splitting technology. Prof. Yagi said, "This result is a great breakthrough in the electrocatalytic water splitting system and could undoubtedly contribute to realize the de-carbonized human society in near future."

Quantum technologies are based on quantum properties of light, electrons, and atoms. In recent decades, scientists have learned to master these phenomena and exploit them in applications. Thus, the construction of a quantum computer for commercial applications is also coming within reach. One of the emerging technologies that is currently being advanced very successfully is ion trap quantum computers. Here, charged particles are trapped with electromagnetic fields in a vacuum chamber and prepared in such a way that they can serve as carriers for information and be used for computing, which includes cooling them to the lowest temperatures permitted by quantum mechanics. However, the quantum mechanical properties exploited in this process are highly error prone. Even the smallest deficiencies can heat up the strongly cooled particles and thereby lead to errors in the processing of quantum information. Possible sources of such faults are weakly conducting or non-conducting materials, which are used, for example, as insulators in a metallic ion trap, or optics, which are necessary for coupling ions with laser light. "Even for ion traps made exclusively of metal, oxide layers on the metals would cause such failures," explains Tracy Northup at the Department of Experimental Physics of the University of Innsbruck in Austria. Northups team together with collaborators in Innsbruck and in the U.S. have found a way to determine the influence of dielectric materials on the charged particles in ion traps.

Experimentally confirmed

This was achieved because the Innsbruck quantum physicists have an ion trap in which they can precisely set the distance between the ions and dielectric optics. Based on an earlier proposal by Rainer Blatt's group, the physicists computed the amount of noise caused by the dielectric material for this ion trap and compared it with data from experiment. "Theory and experiment agree very well, confirming that this method is well suited for determining the influence of dielectric materials on the ions," explains Markus Teller from the Innsbruck team. To calculate the noise, the so-called fluctuation-dissipation theorem from statistical physics was used, which mathematically describes the response of a system in thermal equilibrium to a small external perturbation.

"In quantum computers, there are many possible sources of noise, and it is very difficult to sort out the exact sources," says Tracy Northup. "Our method is the first to quantify the influence of dielectric materials in a given ion trap on the charged particles. In the future, designers of ion trap quantum computers will be able to assess this effect much more accurately and design their devices to minimize these perturbations." After having successfully demonstrated the method on their own ion trap, the Innsbruck physicists now want to apply it to the ion traps of collaborators in the U.S. and Switzerland.

An international research team led by Professor Dr Frank Schäbitz has published a climate reconstruction of the last 200,000 years for Ethiopia. This means that high-resolution data are now available for the period when early Homo sapiens, our ancestors, made their way from Africa to Europe and Asia. Schäbitz and his colleagues determined the dates using a drill core of lake sediments deposited in southern Ethiopia's Chew Bahir Basin, which lies near human fossil sites. Temporal resolution of the samples, reaching nearly 10 years, revealed that from 200,000 to 125,000 years before our time, the climate there was relatively wet, providing enough water and thus abundant plant and animal food resources in the lowlands of East Africa. From 125,000 to 60,000 years ago, it gradually became drier, and particularly dry between 60,000 to 14,000 years ago. The data now obtained fit well with genetic findings, according to which our direct genetic ancestors ('African Eve') left Africa 'successfully' during a wet phase about 70,000 to 50,000 years ago.

The article 'Hydroclimate changes in eastern Africa over the past 200,000 years may have influenced early human dispersal' has appeared in Nature Communications.

Scientists collect information about the environment from lake sediments because, in the best case, sediments are flushed into lakes relatively continuously from the catchment through erosion. In addition to mineral components, sediments include organic material and remains of organisms living in the lake. If lake sediments from suitable lakes can be drilled, these 'proxy data' can be used to draw conclusions about environmental conditions at the time, and thus help to reconstruct the climate.

From November to December 2014, the researchers recovered an approximately 300 metre long drill core from the Chew Bahir Basin in southern Ethiopia, which dries out during the dry season. In its entirety, the drill core dates back to about 620,000 years. 'This enables us to chronologically cover the entire evolutionary history of Homo sapiens in Africa. The work now published on the last 200,000 years of this drill core thus provides very good evidence of the environmental and climate history during the migration of our ancestors,' Schäbitz explained.

'Some of our proxies allow time resolution for specific decades in large sections of the core, which has not been done before for this part of Africa. That way we can capture very short-term climate changes representing less than a human lifetime,' he said. The drill core reveals that the climate of East Africa was largely influenced by changes in solar insolation, which led to either wet or dry climate conditions. From 200,000 to 125,000 years ago, the climate was generally relatively favourable, i.e., the lowlands provided enough water and thus abundant plant and animal food resources for our ancestors. Under such conditions, people could move relatively easily over long distances and even reach the Arabian Peninsula, as evidenced by the oldest fossil finds there (about 175,000 years ago). From 125,000 to 60,000 years ago, however, it gradually became drier, and then particularly dry between 60,000 to 14,000 years ago, with the lake drying up completely several times.

'However, during this period in particular, quite striking, short-term moisture fluctuations can also be observed, the temporal patterns of which are reminiscent of cold-warm climate fluctuations known from Greenland ice cores. So the people who lived in East Africa at that time were exposed to extreme changes in their environments,' Schäbitz said. 'It is interesting that just in the period from 60,000 to 14,000 years ago, when the lowlands of East Africa were repeatedly particularly dry, numerous archaeological findings in the high altitudes of the Ethiopian mountains bear witness to the presence of our ancestors there.' In addition, the weapons and tools of these people also evolved during this time period (transition from Middle to Late Paleolithic in Africa). 'We suspect that the greater "environmental stress" at lower elevations forced this development,' the scientist noted.

Furthermore, the scientists noted that the last major wet phase which we can see in the core fits well in time with the genetic findings: It shows that our direct genetic ancestors 'successfully' left Africa about 70,000 to 50,000 years ago. Their descendants probably reached southeastern Europe 50,000 to 40,000 years ago, where they encountered Neanderthals.

'We hypothesize that the evidence of dry-humid climate fluctuations in East Africa found in our drill core had a significant impact on the evolution and mobility of our ancestors,' said Schäbitz. 'Migration out of Africa was possible several times during the last 200,000 years, during periods when the climate was wetter, and has led to the spread of our ancestors as far as Europe. During the particularly dry phases of the recent past, starting around 60,000 years ago, Homo sapiens groups repeatedly managed to survive in the high altitudes of mountainous Ethiopia.'

LAWRENCE -- The United States has the highest population of incarcerated citizens among developed nations. Every year, roughly 2 million women, the majority held in jails, leave incarceration. The COVID-19 pandemic hit jails and correctional facilities harder than almost any other societal setting. Many of the people leaving incarceration are returning to communities that were also disproportionately affected by the pandemic, yet many people in that population have expressed hesitancy to receive a COVID-19 vaccine.

New research from the University of Kansas found high rates of vaccine hesitancy among women transitioning from incarceration, due to a multitude of reasons, including low health literacy, lack of trust in authorities, and misconceptions about COVID-19 and the vaccine. The COVID-19 pandemic has further affected these women who already had low compliance with cancer screening and prevention recommendations, and they had limited knowledge about topics such as women's health. An online app developed by KU researchers to boost health literacy among this population may be an efficient and cost-effective way to address multiple health topics.

Vaccine hesitancy among women leaving incarceration

Researchers at KU and KU Medical Center published a study in the journal Public Health Nursing about vaccine hesitancy among the target population. It was co-written by Mugur Geana, associate professor of journalism & mass communications and director of KU's Center for Excellence in Health Communications to Underserved Populations; and Sherri Anderson and Megha Ramaswamy, Department of Population Health at KU School of Medicine. Researchers interviewed 25 women recently released from jail between March 5 and 25. The women were part of a larger cohort participating in a National Institutes of Health-funded study on health literacy among incarcerated women, of which Ramaswamy is principal investigator.

While the vaccine was not yet widely available at the time of interviews, the results showed 52% of respondents said they were definitely not willing to receive a vaccine. Only 20% said "yes, they would vaccinate." In addition to those refusing to vaccinate, various degrees of hesitancy were found: 12% said yes, they would vaccinate, but only if they were required because of work or family reasons, while 8% said "maybe, but not right now." Additionally, 4% of respondents said "they would not refuse it if offered but would not voluntarily pursue it" or "yes, with serious concerns." The 76% total hesitancy was attributed to a number of factors such as mistrust in government or the pharmaceutical industry, not having enough information on how vaccines work, listening to conspiracy theories, returning to anti-vaccination communities and others, the authors said.

"We tried to better understand their perceptions and knowledge about COVID-19 and vaccines," Geana said. "We expected to find some hesitancy among these women, but not at these levels. To a certain extent, some of those factors for hesitancy can be addressed or corrected through better education and information provided by people they trust. They can also be addressed by health literacy interventions like those we are developing."

The authors argue the results indicate not only is health education needed for the studied population, but that assumptions should not be made about why people are hesitant to receive a vaccine. There are legitimate reasons, such as health factors preventing some from being able to take vaccines; health providers, communicators and others should not rush to judgment about those who are hesitant. While there is not much preliminary data available about pandemics and women transitioning from incarceration, the results do align with previous research findings that low-income groups and women are two of the most significant predictors of COVID-19 vaccine uncertainty and refusal.

"Probably the No. 1 lesson from this study is that there is an immediate need for intervention about both COVID-19 testing as well as the COVID-19 vaccine for underserved populations," Geana said.

Online intervention to improve women's health literacy after incarceration

Researchers also recently published a study sharing the results of testing of an online health intervention designed to boost health literacy on topics deemed important to women leaving incarceration. The study focuses on the development and pilot testing of an online intervention specifically designed to boost women's health knowledge among the aforementioned underserved population. Published in the Journal of Health Care for the Poor and Underserved, the study was written by Geana and a team of researchers directed by Ramaswamy from the KU School of Medicine.

The researchers partnered with an advisory board, including women transitioning from incarceration, to determine what health topics were important to this audience and the most appropriate format for information delivery. CEHCUP developed the website structure and programming, and it produced the multimedia content for health modules on the topics of sexually transmitted infections, cervical cancer, reproductive planning and breast health. The KU School of Medicine team tested the effectiveness of the online resource, called the SHE WOMEN mHealth Intervention. The project was funded by the National Institutes of Health.

"The way health information for this population is delivered is mostly by in-person sessions during incarceration. A doctor or nurse talks with them for a half-hour or so, and they move on," Geana said. "We decided to move away from that model and use multiple sessions that transition seamlessly and where users can start with any module they like, when they feel they are ready to learn about their health. The web app was designed to collect varied data so we could use it as a research platform to capture usability metrics as well as testing their retention and understanding of the provided information. The research team was also able to interact with the participants individually, if needed, through the web app."

The results showed their knowledge and health literacy improved, and interactions with participants revealed high satisfaction with how the information was delivered. Participants stated they appreciated seeing videos featuring people that reflected their communities, being able to ask questions, receive text messages from researchers reminding them about participation and getting usable information on topics that were central to their lives and health.

The encouraging results show that such an online health literacy intervention can be a successful way to boost knowledge of vulnerable populations in an understandable way, the researchers said, and they plan to study how to make similar programs more widely available and affordable to similar populations across the country. To that end, the researchers also proposed 10 steps for those looking to develop similar programs for boosting health literacy in underserved populations. Chief among them was to form an advisory board of members from the target audience to identify relevant topics, provide feedback on technology, user experience and content development.

"It doesn't matter how much a researcher interacts with an underserved population, we can never have the same experience," Geana said. "The only way to cater to them effectively is to have them as part of the research team."

TROY, N.Y. -- The future of quantum computing may depend on the further development and understanding of semiconductor materials known as transition metal dichalcogenides (TMDCs). These atomically thin materials develop unique and useful electrical, mechanical, and optical properties when they are manipulated by pressure, light, or temperature.

In research published today in Nature Communications, engineers from Rensselaer Polytechnic Institute demonstrated how, when the TMDC materials they make are stacked in a particular geometry, the interaction that occurs between particles gives researchers more control over the devices' properties. Specifically, the interaction between electrons becomes so strong that they form a new structure known as a correlated insulating state. This is an important step, researchers said, toward developing quantum emitters needed for future quantum simulation and computing.

"There is something exciting going on," said Sufei Shi, an assistant professor of chemical and biological engineering at Rensselaer, who led this work. "One of the quantum degrees of freedom that we hope to use in quantum computing is enhanced when this correlated state exists."

Much of Shi's research has focused on gaining a better understanding of the potential of the exciton, which is formed when an electron, excited by light, bonds with a hole -- a positively charged version of the electron. Shi and his team have demonstrated this phenomenon in TMDC devices made of layers of Tungsten disulfide (WS2) and Tungsten diselenide (WSe2). Recently, the team also observed the creation of an interlayer exciton, which is formed when an electron and hole exist in two different layers of material. The benefit of this type of exciton, Shi said, is that it holds a longer lifetime and responds more significantly to an electric field -- giving researchers greater ability to manipulate its properties.

In their latest research, Shi and his team showed how, by stacking TMDCs in a particular manner, they can develop a lattice known as a moiré superlattice. Picture two sheets of paper stacked on top of one another, each with the same pattern of hexagons cut out of them. If you were to shift the angle of one of the pieces of paper, the hexagons would no longer perfectly match up. The new formation is similar to that of a moiré superlattice.

The benefit of such a geometry, Shi said, is that it encourages electrons and interlayer excitons to bond together, further increasing the amount of control researchers have over the excitons themselves. This discovery, Shi said, is an important step toward developing quantum emitters that will be needed for future quantum simulation and quantum computing.

"It has essentially opened the door to a new world. We see a lot of things already, just by peeking through the door, but we have no idea what is going to happen if we open the door and get inside," Shi said. "That is what we want to do, we want to open the door and get inside."

A funny thing happened on the way to discovering how zinc impacts kidney stones - two different theories emerged, each contradicting the other. One: Zinc stops the growth of the calcium oxalate crystals that make up the stones; and two: It alters the surfaces of crystals which encourages further growth. Now it can be told - both theories are correct as reported in the America Chemical Society journal Crystal Growth & Design by Jeffrey Rimer, Abraham E. Dukler Professor of Chemical and Biomolecular Engineering at the University of Houston, who conducted the first study to offer some resolution to the differing hypotheses.

"What we see with zinc is something we haven't seen before. It does slow down calcium oxalate crystal growth and at the same time it changes the surface of the crystals, causing defects in the form of intergrowths. These abnormalities create centers for new crystals to nucleate and grow," reports Rimer, who refers to the effect as a double-edged sword.

The formation of kidney stones is a pathological condition that has increased in frequency among patients, leading to an increased amount of suffering and steep rise in medical costs.

Though calcium oxalate crystals are found everywhere, the most naturally abundant form of these crystals are calcium oxalate monohydrates (COM), the kind found in human kidney stone disease. Along with COM, kidney stones are composed of various hard deposits of inorganic salts and organic compounds (e.g., proteins) crystallizing or sticking together in concentrated urine. They can be severely painful to pass through the urinary tract.

In this study, Rimer and his team used a combination of in vitro experiments and computational modeling to decode the effects of zinc on COM crystal growth.

"The techniques we're using in our lab to investigate these systems enable us to get a better picture and to deconstruct these complex systems as a means of identifying new ways to prevent kidney stone formation," said Rimer. "These are enabling tools that allow us to understand at an almost molecular level how various species in urine can regulate crystal growth."

Rimer's findings on the dual role of zinc on COM was confirmed by atomic force microscopy measurements showing a unique ability of zinc ions to alter the termination of crystal surfaces.

The team compared the impact of zinc on COM, with similar ions like magnesium.

"We wondered what would happen if we used alternative ions commonly found in urine, such as magnesium, and the answer was nothing. It had little to no effect, whereas zinc had a major effect. This is an excellent demonstration of how subtle differences in the nature of various species impacts their interaction with crystal surfaces," said Rimer.

Albeit very small, with a carapace width of only 3 cm, the Atlantic mangrove fiddler crab Leptuca thayeri can be a great help to scientists seeking to understand more about the effects of global climate change. In a study published in the journal Estuarine, Coastal and Shelf Science, Brazilian researchers supported by São Paulo Research Foundation - FAPESP show how the ocean warming and acidification forecast by the end of the century could affect the lifecycle of these crustaceans.

Embryos of L. thayeri were exposed to a temperature rise of 4 °C and a pH reduction of 0.7 against the average for their habitat, growing faster as a result. However, a larger number of individuals died before reaching the final embryonic stage compared with those allowed to remain in conditions typical for the environment normally inhabited by the species.

"This crab is very important ecologically. Its burrows contribute to the organic matter cycle, and its larvae serve as food for many other species. We can therefore assume that the alterations to its embryos caused by climate change will have a cascade effect. Animals like these with a longer embryonic stage are particularly endangered," said Tânia Márcia Costa, principal investigator for the project. Costa is a professor at the Bioscience Institute of São Paulo State University's Coast Campus (IB-CLP-UNESP) in São Vicente.

The project was supported by the FAPESP Research Program on Global Climate Change (RPGCC).

The temperature rise simulated in the experiments was based on the forecast for the end of the century made by the Intergovernmental Panel on Climate Change (IPCC). The parameter for the change in pH came from a study published in Nature in 2003 by researchers from United States.

L. thayeri is tiny and extremely abundant, with a typical mangrove serving as home for some 100 individuals per square meter. The species is often called an "ecosystem engineer" because to build chimney burrows in which to shelter, reproduce and incubate eggs, it moves organic matter from deep mud to the surface, where smaller organisms feed on the nutrients, as shown by the São Vicente group in an article
published in 2017.

"More research is needed to understand the combined effects of climate stressors on organisms, especially in the initial stages of their lives. These are usually the most sensitive to warming, falling pH levels and other stresses associated with climate change. The few studies that have been done used very generic values for temperature and acidity, whereas mangroves are highly dynamic and have their own microclimate," said Juan Carlos Farias Pardo, currently a PhD candidate at Norway's University of Agder (UiA) and the Norwegian Institute for Water Research (NIVA).The study was conducted as part of his master's research at IB-CLP-UNESP with a scholarship from FAPESP.

In the laboratory

To reproduce the crab's habitat as accurately as possible, the researchers spent months going into the field to measure temperature, salinity and acidity in the burrows where ovigerous (egg-laying) females live. The data was used for control in the laboratory experiments.

Eggs were removed from females and placed in water with the same salinity as in the habitat. Embryos were exposed to different combinations of temperature (26 °C or 30 °C) and pH (6.9 or 6.2). Observations were conducted for ten days. Embryos of this species are expected to develop completely in this timeframe, with fully formed eyes and strong heartbeats.

In the experiments, embryos developed faster in warmer, more acid water than the control group but also died more than embryos kept in conditions equivalent to those of the habitat. Egg volume was smaller in warmer water (30 °C) with normal acidity, and larger in similarly warm but more acid water.

"We concluded that faster development isn't necessarily better. They grew faster in response to the stressors but died more frequently. Larger egg volume in more acid water may have been a consequence of less efficient gas exchange, making them swell up," Pardo said, adding that the group is preparing more experiments to investigate later stages of development in the same species.

"Even if 100% of the embryos survive these climate changes, this is only the first stage of development. Mortality is naturally high before they reach adulthood because of their many predators. In any case, we don't know how this level of stress on the embryo will affect later stages," Costa said.

Previous research by the group showed how rising temperatures force physiological adaptations in two other species of fiddler crab, and influence territorial expansion in a third.

In a new project supported by FAPESP, Costa will investigate how stresses deriving from climate change affect interactions between herbivores and plants, predators and prey.

An interdisciplinary group of researchers from across the globe has comprehensively examined the sources and health effects of air pollution -- not just on a global scale, but also individually for more than 200 countries.

They found that worldwide, more than one million deaths were attributable to the burning of fossil fuels in 2017. More than half of those deaths were attributable to coal.

Findings and access to their data, which have been made public, were published today in the journal Nature Communications.

Pollution is at once a global crisis and a devastatingly personal problem. It is analyzed by satellites, but PM2.5 -- tiny particles that can infiltrate a person's lungs -- can also sicken a person who cooks dinner nightly on a cookstove.

"PM2.5 is the world's leading environmental risk factor for mortality. Our key objective is to understand its sources," said Randall Martin, the Raymond R. Tucker Distinguished Professor in the Department of Energy, Environmental & Chemical Engineering at Washington University in St. Louis.

Martin jointly led the study with Michael Brauer, a professor of public health at the University of British Columbia. They worked with specific datasets and tools from the Institute for Health Metrics and Evaluation at the University of Washington, the Joint Global Change Research Institute at the University of Maryland and Pacific Northwest National Laboratory, as well as other researchers from universities and organizations across the world, amassing a wealth of data, analytical tools and brainpower.

First author Erin McDuffie, a visiting research associate in Martin's lab, used various computational tools to weave the data together, while also enhancing them. She developed a new global dataset of air pollution emissions, making it the most comprehensive dataset of emissions at the time. McDuffie also brought advances to the GEOS-Chem model, an advanced computational tool used in the Martin lab to model specific aspects of atmospheric chemistry.

With this combination of emissions and modeling, the team was able to tease out different sources of air pollution -- everything from energy production to the burning of oil and gas to dust storms.

This study also used new techniques to remote sensing from satellites in order to assess PM2.5 exposure across the globe. The team then incorporated information about the relationship between PM2.5 and health outcomes from the Global Burden of Disease with these exposure estimates to determine the relationships between health and each of the more than 20 distinct pollution sources.

As McDuffie put it: "How many deaths are attributable to exposure to air pollution from specific sources?"

Ultimately, the data reinforced much of what researchers already suspected, particularly on a global scale. It did offer, however, quantitative information in different parts of the world, teasing out which sources are to blame for severe pollution in different areas.

For instance, cookstoves and home-heating are still responsible for the release of particulate matter in many regions throughout Asia and energy generation remains a large polluter on the global scale, McDuffie said.

Apples to apples
One unique aspect of this research is its use of the same underlying datasets and methodology to analyze pollution on different spatial scales.

"Previous studies end up having to use different emissions data sets or models all together," said first author Erin McDuffie. In those instances, it is difficult to compare results in one place versus another.

"We can more directly compare results between countries," McDuffie said. "We can even look at pollution sources in places that have implemented some mitigation measures, versus others that haven't to get a more complete picture of what may or may not be working."

And natural sources play a role, as well. In West sub-Saharan Africa in 2017, for instance, windblown dust accounted for nearly three quarters of the particulate matter in the atmosphere, compared with the global rate of just 16 percent. The comparisons in this study are important when it comes to considering mitigation.

"Ultimately, it will be important to consider sources at the subnational scale when developing mitigation strategies for reducing air pollution," McDuffie said.

Martin and McDuffie agreed that, while a takeaway from this work is, simply put, air pollution continues to sicken and kill people, the project also has positive implications.

Although pollution monitoring has been increasing, there are still many areas that do not have the capability. Those that do may not have the tools needed to determine, for instance, how much pollution is a product of local traffic, versus agricultural practices, versus wildfires.

"The good news is that we may be providing some of the first information that these places have about their major sources of pollution," McDuffie said. They may otherwise not have this information readily available to them. "This provides them with a start."

WASHINGTON -- Researchers have developed a way to dynamically switch the surface of liquid
metal between reflective and scattering states. This technology could one day be used to create electrically controllable mirrors or illumination devices.

Liquid metals combine the electrical, thermal and optical properties of metals with the fluidity of a liquid. The new approach uses an electrically driven chemical reaction to create switchable reflective surfaces on a liquid metal. No optical coatings nor polishing steps, which are typically required to make reflective optical components, are necessary to make the liquid metal highly reflective.

In the Optical Society (OSA) journal Optical Materials Express, researchers led by Yuji Oki of Kyushu University in Japan show that switching between reflective and scattering states can be achieved with just 1.4 V, about the same voltage used to light a typical LED. The researchers collaborated with Michael D. Dickey's research team at North Carolina State University to develop the new method, which can be implemented at ambient temperature and pressures.

"In the immediate future this technology could be used to create tools for entertainment and artistic expression that have never been available before," said Oki. "With more development, it might be possible to expand this technology into something that works much like 3D printing for producing electronically controlled optics made of liquid metals. This could allow the optics used in light-based health testing devices to be easily and inexpensively fabricated in areas of the world that lack medical laboratory facilities."

Creating an optical surface

In the new work, the researchers created a reservoir using an embedded flow-channel. They then used a "push-pull method" to form optical surfaces by either pumping gallium-based liquid metal into or sucking it out of the reservoir. This process formed convex, flat, or concave surfaces; each with different optical properties.

Then, by applying electricity, the researchers initiated a chemical reaction that reversibly oxidizes the liquid metal. The oxidation changes the liquid's volume in a way that creates many small scratches on the surface that cause light to scatter. When electricity is applied in the opposite direction, the liquid metal returns to its original state. The liquid metal's surface tension causes the scratches to disappear, restoring the surface to a clean reflective mirror state.

The researchers discovered the new technique serendipitously while experimenting with a liquid metal to see if it could be used to make molds to use with a silicone elastomer. "Our intention was to use oxidation to change the surface tension and reinforce the surface of the liquid metal," said Oki. "However, we found that, under certain conditions, the surface would spontaneously change into a scattering surface. Instead of considering this a failure, we optimized the conditions and verified the phenomenon."

Characterizing the phenomenon

The researchers electrochemically and optically characterized the different surfaces that were created by applying electricity. They found that changing the voltage on the surface from -800 mV to +800 mV would decrease the light intensity as the surface changed from reflective to scattering. The electrochemical measurements revealed that a voltage change of 1.4 V was sufficient to create redox reactions with good reproducibility.

"We also found that under certain conditions the surface can be slightly oxidized and still maintain a smooth reflective surface," said Oki. "By controlling this, it might be possible to create even more diverse optical surfaces using this approach that could lead to applications in advanced devices such as biochemical chips or be used to make 3D printed optical elements."

Methane is a strong greenhouse gas that plays a key role in Earth's climate. Anytime we use natural gas, whether we light up our kitchen stove or barbeque, we are using methane.

Only three sources on Earth produce methane naturally: volcanoes, subsurface water-rock interactions, and microbes. Between these three sources, most is generated by microbes, which have deposited hundreds of gigatons of methane into the deep seafloor. At seafloor methane seeps, it percolates upwards toward the open ocean, and microbial communities consume the majority of this methane before it reaches the atmosphere. Over the years, researchers are finding more and more methane beneath the seafloor, yet very little ever leaves the oceans and gets into the atmosphere. Where is the rest going?

A team of researchers led by Jeffrey J. Marlow, former postdoctoral researcher in Organismic and Evolutionary Biology at Harvard University, discovered microbial communities that rapidly consume the methane, preventing its escape into Earth's atmosphere. The study published in Proceedings of the National Academy of Sciences collected and examined methane-eating microbes from seven geologically diverse seafloor seeps and found, most surprisingly, that the carbonate rocks from one site in particular hosts methane-oxidizing microbial communities with the highest rates of methane consumption measured to date.

"The microbes in these carbonate rocks are acting like a methane bio filter consuming it all before it leaves the ocean," said senior author Peter Girguis, Professor of Organismic and Evolutionary Biology, Harvard University. Researchers have studied microbes living in seafloor sediment for decades and know these microbes are consuming methane. This study, however, examined microbes that thrive in the carbonate rocks in great detail.

Seafloor carbonate rocks are common, but in select locations, they form unusual chimney-like structures. These chimneys reach 12 to 60 inches in height and are found in groups along the seafloor resembling a stand of trees. Unlike many other types of rocks, these carbonate rocks are porous, creating channels that are home to a very dense community of methane-consuming microbes. In some cases, these microbes are found in much higher densities within the rocks than in the sediment.

During a 2015 expedition funded by the Ocean Exploration Trust, Girguis discovered a carbonate chimney reef off the coast of southern California at the deep sea site Point Dume. Girguis returned in 2017 with funding from NASA to build a sea floor observatory. Upon joining Girguis's lab, Marlow, currently Assistant Professor of Biology at Boston University, was studying microbes in carbonates. The two decided to conduct a community study and gather samples from the site.

"We measured the rate at which the microbes from the carbonates eat methane compared to microbes in sediment," said Girguis. "We discovered the microbes living in the carbonates consume methane 50 times faster than microbes in the sediment. We often see that some sediment microbes from methane-rich mud volcanoes, for example, may be five to ten times faster at eating methane, but 50 times faster is a whole new thing. Moreover, these rates are among the highest, if not the highest, we've measured anywhere."

"These rates of methane oxidation, or consumption, are really extraordinary, and we set out to understand why," said Marlow.

The team found that the carbonate chimney sets up an ideal home for the microbes to eat a lot of methane really fast. "These chimneys exists because some methane in fluid flowing out from the subsurface is transformed by the microbes into bicarbonate, which can then precipitate out of the seawater as carbonate rock," said Marlow. "We're still trying to figure out where that fluid - and its methane - is coming from."

The micro-environments within the carbonates may contain more methane than the sediment due to its porous nature. Carbonates have channels that are constantly irrigating the microbes with fresh methane and other nutrients allowing them to consume methane faster. In sediment, the supply of methane is often limited because it diffuses through smaller, winding channels between mineral grains.

A startling find was that, in some cases, these microbes are surrounded by pyrite, which is electrically conductive. One possible explanation for the high rates of methane consumption is that the pyrite provides an electrical conduit that passes electrons back and forth, allowing the microbes to have higher metabolic rates and consume methane quickly.

"These very high rates are facilitated by these carbonates which provide a framework for the microbes to grow," said Girguis. "The system resembles a marketplace where carbonates allow a bunch of microbes to aggregate in one place and grow and exchange - in this case, exchange electrons - which allows for more methane consumption."

Marlow agreed, "When microbes work together they're either exchanging building blocks like carbon or nitrogen, or they're exchanging energy. And one kind of way to do that is through electrons, like an energy currency. The pyrite interspersed throughout these carbonate rocks could help that electron exchange happen more swiftly and broadly."

In the lab, the researchers put the collected carbonates into high pressure reactors and recreated conditions on the sea floor. They gave them isotopically labeled methane with added Carbon-14 or Deuterium (Hydrogen-2) in order to track methane production and consumption. The team next compared the data from Point Dume to six additional sites, from the Gulf of Mexico to the coast of New England. In all locations, carbonate rocks at methane seeps contained methane-eating microbes.

"Next we plan to disentangle how each of these different parts of the carbonates - the structure, electrical conductivity, fluid flow, and dense microbial community - make this possible. As of now, we don't know the exact contribution of each," said Girguis.

"First, we need to understand how these microbes sustain their metabolic rate, whether they're in a chimney or in the sediment. And we need to know this in our changing world in order to build our predictive power," said Marlow. "Once we clarify how these many interconnected factors come together to turn methane to rock, we can then ask how we might apply these anaerobic methane-eating microbes to other situations, like landfills with methane leaks."

June 14, 2021 - Last fall, the Mullen fire west of Laramie raged for the better part of two months, burning more than 176,000 acres and 70 structures in Wyoming's Carbon and Albany counties, and in Jackson County, Colo.

Unfortunately, this scenario was typical during the intense 2020 fire season in the Rocky Mountain region, an area of Colorado and southern Wyoming where high-elevation forests are burning more than at any point in the past 2,000 years, according to a study in which a University of Wyoming faculty member was instrumental.

"Global warming is causing larger fires in Rocky Mountain forests than have burned for thousands of years," says Bryan Shuman, a professor in the UW Department of Geology and Geophysics. "The last time anything similar may have occurred was during a warm portion of the medieval era."

Shuman was the main co-author of a paper, titled "Rocky Mountain Subalpine Forests Now Burning More Than Any Time in Recent Millennia," that was published today (June 14) in the Proceedings of the National Academy of Sciences (PNAS). The journal is one of the world's most prestigious multidisciplinary scientific serials, with coverage spanning the biological, physical and social sciences.

Philip Higuera, a professor of fire ecology in the W.A. Franke College of Forestry and Conservation at the University of Montana, was the paper's lead author. Kyra Wolf, a Ph.D. candidate in paleoecology and forest ecology at the University of Montana, also contributed to the paper.

Higuera and Shuman conceived and designed the study, while Higuera and Wolf analyzed the data, a unique network of fire-history records, to understand how current fire activity compared to wildfires of the past. The 2020 fire season marks the emergence of 21st century fire regimes with distinctly higher rates of burning, not only from the late 20th century but relative to the past two millennia.

By November 2020, wildfires in southern Wyoming and northern Colorado were responsible for 72 percent of the total area burned in high-elevation, subalpine forests since 1984. During 2020, Colorado had experienced three of its largest fires on record.

"As the 2020 fire season unfolded, we realized we already had a well-defined understanding of the fire history of many of the places burning, based on over 20 lake sediment records our teams had collected over the past 15 years," Higuera says. "When the smoke settled, we thought 'Wow, we may have witnessed something truly unprecedented here.' So, we combined the existing records for the first time and compared them to recent fire activity. To our surprise, 2020 indeed pushed fire activity outside the range of variability these forests have experienced over at least the past two millennia."

Researchers used charcoal found in lake sediment records to assemble the fire history across the Rocky Mountains. They discovered that, since 2000, wildfires are burning nearly twice as much area, on average, compared to the last 2,000 years.

Over that 2,000-year period, fires in high-elevation, subalpine forest historically burned, on average, once every 230 years. In the 21st century, those fires now occur, on average, every 117 years. This is 22 percent higher than the maximum rate -- which took place during the Medieval Climate Anomaly (770-870) -- reconstructed over the past two millennia. During the Medieval Climate Anomaly, Northern Hemisphere temperatures were 0.3 degrees Celsius above the average in the 20th century.

"The results indicate that, if fires continue to burn as often as they do now, every forest in the region could be burned by the beginning of the next century," Shuman explains. "In the past, it would have taken 200 to 300 years, if not longer, for fires to affect that much area."

In the Rocky Mountains of northern Colorado and southern Wyoming, 840,000 acres burned between 1984 and 2019, Shuman says. Another 660,000 acres burned in 2020 alone. Approximately 1.1 million acres burned in the past decade in the Colorado-Wyoming study area, even though only 400,000 acres -- less than half as much -- burned in the previous 25 years, Shuman says.

Subalpine forests are becoming less resilient and more susceptible to fires because the climate is warming. Because humidity was extremely low, temperatures were high, and storm events produced high winds, forest management had little impact on the 2020 fires. They burned designated wilderness and national parks with limited fuel management; heavily managed areas with substantial timber removal; and intact forest and areas with extensive beetle kill. The extreme climate completely overrode all types of forest management, according to Shuman.

"Snowfall in our high-elevation forests is lower now than in past decades, and summers are hotter. The changes convert trees into dry fuel, primed and ready to burn," Shuman says. "With less snow now, the fire season lasts longer than before. When areas burn, the fires are bigger. They can burn longer.

"Then, after the fires, big areas with few live trees mean few seeds to help forests regrow and, even when seeds are plentiful, seedlings can often die from drought and heat," he continues. "Some forests may never grow back."

"It isn't unexpected to have more fires as temperatures rise. Our records show that fire tracked past variations in climate just as it does today," Wolf adds. "What's striking is that temperatures and, correspondingly, fire are now exceeding the range that these forests have coped with for thousands of years -- largely as a result of human-caused climate change."

Continual warming will reinforce newly emerging fire activity in these high-elevation forests, with significant implications for ecosystems and society, according to the paper.

"It may sound dire, but it's critical to remember that we have ample opportunities to limit or reverse climate warming, while still working to adapt to the increasing fire activity expected in upcoming decades," Higuera says.

Shuman helped plan the study, which came about because of more than $600,000 in grants he was able to obtain from the National Science Foundation to support undergraduate and graduate student research at UW.

"We were able to examine the 2020 fire season because of a decade of student projects at UW that revealed how often our forests have burned in the past few thousand years," Shuman says.