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What The Study Did: This study combined the results of 47 studies with 23,000 participants to estimate how common cannabis withdrawal syndrome (symptoms include irritability, nervousness or anxiety, depression and headache) is among individuals who stop regular use.

Authors: Anees Bahji, M.D., of Queen's University in Kingston, Ontario, Canada, 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.2020.2370)

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

Electrocatalysis is one of the most studied topics in the field of material science, because it is extensively involved in many important energy-related processes, such as the oxygen reduction reaction (ORR) for fuel cells, the hydrogen evolution reaction (HER) for green hydrogen production, and the oxygen evolution reaction (OER) for metal-air batteries. Noble metal aerogels (NMAs) emerge as a new class of outstanding electrocatalysts due to the combined feature of metals and aerogels. However, limited by the available compositions, the explored electrocatalytic reactions on NMAs are highly restricted and certain important electrochemical processes have not been investigated.

Original Publication:

Du, R.; Jin, W.*; Hübner, R.; Zhou, L.; Hu, Y.; Eychmüller, A.*, Engineering Multimetallic Aerogels for pH-Universal HER and ORR Electrocatalysis. Adv. Energy Matter. 2020, DOI: 10.1002/aenm.201903857.

Ran Du from China is a Alexander von Humboldt research fellow working as postdoc in the physical chemistry group of Professor Alexander Eychmüller at TU Dresden since 2017. In collaboration with Prof. Wei Jin from the Jiangnan University, China, they recently created various noble metal aerogels, disclosing their unprecedented potential for diverse pH-universal electrochemical catalysis, including oxygen reduction reaction (ORR), hydrogen evolution reaction (HER), and electrochemical water splitting. These findings largely span the application territory of NMAs for fuel cells, green hydrogen production and many more. The work was published in the renowned journal Advanced Energy Materials.

By adopting a strong salting-out agent (i.e. ammonium fluoride (NH4F)) as an initiator to trigger gelation, the composition of the as-obtained noble metal aerogels (NMAs) was extended to various bi- and trimetallic systems. Subsequently Ran Du and his team manipulated the chemical composition, and thus expanding the application territory of NMAs to pH-universal ORR electrocatalysis, HER electrocatalysis, and electrochemical water splitting. Notably, the Au-Rh aerogel and Au-Pt aerogel manifested extraordinary pH-universal performance for HER and ORR electrocatalysis, respectively, both of which considerably outperform commercial Pt/C (platinum on carbon) in wide pH environments.

"Further research directions may be placed on morphology-controlled NMA synthesis, and the establishment of the correlations between the structural features of NMAs and their electrocatalytic properties," assumes chemist Ran Du.

Korea Brain Research Institute (KBRI, headed by Suh Pan-Ghill) announced on the 6th of April, 2020 that the KBRI research team led by Dr. Kea Joo Lee (Collaboration with Dr. Daniel Pak at Georgetown University) presented their discoveries regarding a novel function for MAP2 in synaptic strengthening.

The results of this study were published in the online version (Early View) of FASEB Journal. The paper title and authors are listed as follows:

*Title: Microtubule-associated protein 2 mediates induction of long-term potentiation in hippocampal neurons.
*Authors: Yoonju Kim, You-Na Jang, Ji-Young Kim, Nari Kim, Seulgi Noh, Hyeyeon Kim, Bridget N. Queenan, Ryan Bellmore, Ji Young Mun, Hyungju Park, Jong Cheol Rah, Daniel T. S. Pak, Kea Joo Lee

Neurons in the brain communicate with each other via the synapses. Long lasting changes in synaptic structure and function occur when we learn new things or memorize new information (synaptic plasticity).

Long-term potentiation (LTP) is the best-studied cellular mechanism of synaptic plasticity that underlies learning and memory, and refers to a persistent strengthening of synapses upon repeated stimulations. However, many of the molecules that mediate synaptic remodeling and trafficking during LTP remain to be discovered.

The research team headed by Dr. Kea Joo Lee revealed that MAP2* plays an essential role in induction of long-term potentiation in the mature neurons.

*MAP2 (microtubule-associated protein 2) is a cytoskeletal protein, which is enriched in the neuronal dendritic shafts, and is known to be important for dendritic outgrowth during development.

The research team demonstrated that LTP induction is abolished when MAP2 is deficient in the mouse hippocampus and primary cultured neurons through systematic neurobiological approaches, including confocal microscopy, electrophysiology, and molecular cell biology.

Through real-time live-cell imaging and electron microscopy, the research team discovered that MAP2 proteins, present on the dendritic shafts of the neurons, rapidly move to the synapses when long-term potentiation is induced. They also showed that the dynamic MAP2 translocation to synapses is tightly coupled with LTP-induced expansion of dendritic spines* and surface delivery of AMPA receptors*, which are critical for activating the synapses.

*AMPA receptor: A type of ionic glutamate receptor that exists in the excitatory synapses of the neurons and mediates the rapid neurotransmissions in the synapses.

*Dendritic spines: Tiny protrusions on the surface of the neuronal dendrites, which serve as the postsynaptic structures present on the excitatory synapses.

This study is significant because it sheds light on the possibility of MAP2, which was previously known as a dendrite-labeling protein, being involved in the formation of memories by participating in the process of synaptic potentiation.

In addition, it has been evaluated to be a step forward towards the resolution of the longstanding question of "how memories are formed and maintained", thus providing basic information that could potentially be applied to design the treatment strategies for the memory-related diseases.

Dr. Kea Joo Lee, who led this study mentioned that "we plan to continue studying the impact of synaptic translocation of MAP2 on behavioral learning. We hope that the results of our study will provide key insights into synaptic plasticity mechanisms and important clues to develop therapeutic strategies for synaptic disorders such as autism, schizophrenia, and Alzheimer's disease.

Nagoya University researchers have found that in response to the nitrogen demand of leaves, plants produce a hormone that travels from the leaves to the roots to stimulate the uptake of nitrogen from the soil. This hormone is produced in the leaves when they run short of nitrogen, and acts as a signal that regulates the demand and supply of nitrogen between the plant's shoot and the root. The findings have recently been published online in the journal Nature Communications.

Nitrogen is an essential nutrient for plant growth and is very important for crop production. However, often too much nitrogen fertilizer is used, leading to contamination of the environment and rising food prices. What if plants could be made to regulate their own intake of nitrogen more effectively?

Nagoya University researchers have found the key to doing this. "By enhancing the pathway of this hormone, plants could be able to absorb nitrogen nutrients more efficiently, which may eventually minimize the use of fertilizers," says Professor Yoshikatsu Matsubayashi of the Graduate School of Science at Nagoya University.

Plant roots take up nitrogen nutrients in the form of nitrate from the soil -- how much nitrogen a plant needs depends on the shoot growth stage. The larger and more numerous the leaves and stems become, the more nitrogen a plant needs.

The research team studied how plant roots sense nitrogen demand in the shoots. A previous study using a plant called Arabidopsis (better known as thale cress) had shown that certain hormones, named C-terminally encoded peptide (CEP) and CEP downstream (CEPD), respectively, modulate communications between the nitrogen-starved roots and other roots via leaves. The previous study had also revealed that plants produce other hormones that are structurally similar to CEPD.

In the new study, Prof. Matsubayashi and colleagues also focused on these hormones in Arabidopsis, analyzing each of their functions and thereby identifying a peptide that can strongly promote the absorption of nitrogen. The peptide, named CEP downstream-like 2 (CEPDL2), was present in leaf veins and would be produced rapidly in large amounts when the leaf ran short of nitrogen. Simultaneously, the CEPDL2 peptide would flow from shoot to roots.

In contrast, the researchers demonstrated that on plants where the CEPDL2 peptide had been destroyed, leaves were still small in the later growth period when the shoot requires a lot of nitrogen. "This means the plant cannot grow properly without this peptide, showing that the CEPDL2 peptide is the signal that regulates the balance of demand and supply between leaves and roots," Prof. Matsubayashi says. "Our findings highlight one extraordinary way in which plants sense and adapt to changing conditions."

An international team of researchers has tested more than 10,000 compounds to identify six drug candidates that may help treat COVID-19.

The research, involving University of Queensland scientist Professor Luke Guddat, tested the efficacy of approved drugs, drug candidates in clinical trials and other compounds.

"Currently there are no targeted therapeutics or effective treatment options for COVID-19," Professor Guddat said.

"In order to rapidly discover lead compounds for clinical use, we initiated a program of high-throughput drug screening, both in laboratories and also using the latest computer software to predict how different drugs bind to the virus.

Professor Guddat said the project targeted the main COVID-19 virus enzyme, known as the main protease or Mpro, which plays a pivotal role in mediating viral replication.

"This makes it an attractive drug target for this virus, and as people don't naturally have this enzyme, compounds that target it are likely to have low toxicity.

"We add the drugs directly to the enzyme or to cell cultures growing the virus and assess how much of each compound is required to stop the enzyme from working or to kill the virus.

"If the amount is small, then we have a promising compound for further studies."

After assaying thousands of drugs, researchers found of the six that appear to be effective in inhibiting the enzyme, one is of particular interest.

"We're particularly looking at several leads that have been subjected to clinical trials including for the prevention and treatment of various disorders such as cardiovascular diseases, arthritis, stroke, atherosclerosis and cancer," Professor Guddat said.

"Compounds that are already along the pipeline to drug discovery are preferred, as they can be further tested as antivirals at an accelerated rate compared to new drug leads that would have to go through this process from scratch."

After the enzyme's structure was made public, the team received more than 300 requests for more information, even before the paper was published.

"To provide an analogy, we've provided scientists with a fishing pole, the line and the exact bait, and have in only one month caught some fish," Professor Guddat said.

"Now it's up to us and the other fisherman - our fellow scientists globally - to take full advantage of this breakthrough."

"With continued and up-scaled efforts we are optimistic that new candidates can enter the COVID-19 drug discovery pipeline in the near future."

Spokane, Wash. - Many cancers can be successfully treated, but treatment itself often comes with risks as well. Cancer therapy that uses anthracyclines--a class of commonly used chemotherapy drugs--has been associated with heart damage that can eventually result in heart failure. It is thought to be the reason why heart disease is a leading cause of death in cancer survivors, immediately following cancer recurrence.

Scientists have not fully understood how exposure to anthracyclines can lead to heart failure, but a new study led by researchers at Washington State University has made a giant leap toward that goal. In a recent paper published in the Journal of Biological Chemistry, the research team showed that a protein named FOXO1 plays a critical role in heart damage resulting from treatment with doxorubicin, an anthracycline chemotherapy drug. Using a rodent model, they also demonstrated that by suppressing FOXO1 through the use of FOXO1 inhibitor drugs they could prevent doxorubicin-induced heart damage.

Their discovery opens up possibilities for the development of new combination drugs or treatment strategies to reduce heart damage from cancer treatment, which could help increase the life expectancy of cancer survivors.

The new study builds on earlier work done by study co-author Brian Jensen, a cardiologist at the University of North Carolina Chapel Hill. Jensen measured the size, or mass, of patients' hearts starting one month after they received doxorubicin until six months afterwards and found that their hearts had become smaller.

"We believe the reason that the heart eventually undergoes failure is because chemotherapy initially makes the heart smaller," said Zhaokang Cheng, an assistant professor in the WSU College of Pharmacy and Pharmaceutical Sciences and senior author on the study. Since a smaller heart has to labor more to pump the same amount of blood through the body, he explained that this may over time lead the heart to grow larger to meet the body's demand. This forced growth weakens the heart and may ultimately cause it to fail.

In the new study, Cheng and his research team set out to understand why the heart initially becomes smaller in response to doxorubicin chemotherapy treatment, which carries two possible explanations: one is that doxorubicin causes cell death, reducing the overall number of heart cells. The other is that it causes a reduction in the size of each heart cell, which is known as atrophy.

First, they delved into how chemotherapy might cause heart cell death. In a previous study, the WSU research team showed that doxorubicin can activate a protein known as CDK2. They also demonstrated that this activation of CDK2 led to increased expression of a gene known as Bim, which causes cell death. However, it was not clear how CDK2 activation and Bim expression were connected. Their new study revealed FOXO1 as being the missing link. FOXO1 is a transcription factor, a protein that binds to the DNA of other genes to turn them on or off. Their rodent model showed that CDK2 can activate FOXO1, and when FOXO1 becomes active it increases Bim expression, which eventually leads to cell death.

Next, they looked at whether exposure to doxorubicin causes a reduction in heart cell size. Their measurements showed that after treatment with doxorubicin, heart cell size was clearly smaller.

They then looked at whether manipulating FOXO1 could protect the heart during chemotherapy. In another rodent study, they administered doxorubicin along with a drug that inhibits FOXO1. The research team found that both the overall heart size and the heart cell size were maintained.

"That was a surprise," Cheng said. "We used this drug because we had hypothesized that it could prevent cell death, but we didn't expect that it could also protect the heart from atrophy."

Finally, they looked at how exactly the FOXO1 inhibitor protects the heart from both cell death and atrophy. For cell death, the answer was already clear based on what they had found so far, Cheng said. That is, inhibiting FOXO1 decreases the expression of the Bim gene, which plays a critical role in cell death. For atrophy, the team found that inhibiting FOXO1 reduces the expression of a gene called MuRF1. A previous study by Jensen had suggested that MuRF1 is involved in doxorubicin-induced atrophy, but the mechanism by which this happened had been unclear until now.

If their findings hold up in further studies and clinical trials, the team's discovery may eventually lead to promising new treatment strategies or drugs that combine the FOXO1 inhibitor with doxorubicin or other anthracyclines. This would allow physicians to maximize the effectiveness of cancer treatment while minimizing damaging side effects to the heart.

CHAMPAIGN, Ill. -- The soybean cyst nematode sucks the nutrients out of soybean roots, causing more than $1 billion in soybean yield losses in the U.S. each year. A new study finds that one type of fungi can cut the nematodes' reproductive success by more than half.

The researchers report their findings in the journal Plant Disease.

"Soybean cyst nematodes survive in the soil as eggs in cysts," said Glen Hartman, a researcher for the U.S. Department of Agriculture's Agricultural Research Service in the department of crop sciences at the University of Illinois at Urbana-Champaign. Hartman led the new research with graduate student Michelle Pawlowski. "The eggs hatch at the start of the growing season, and the juveniles penetrate root tissue and migrate into the plant's vascular system. The females find a feeding site and stay there for the rest of their lives. They take nutrients away from the soybean plant, which reduces plant productivity."

Previous studies have found that fungi in the soil that form mutually beneficial relationships with soybeans and other plants can influence the success of plant parasitic nematodes, including SCN. But the effectiveness of using these "arbuscular mycorrhizal fungi" to thwart plant parasitic fungi varies from study to study, making growers reluctant to embrace this as a method of control, Hartman said.

"In this study, we focused on five different species of arbuscular mycorrhizal fungi to see if they differed in their ability to protect soybeans against SCN," Pawlowski said.

The researchers inoculated young soybean plants with fungi and SCN in greenhouse experiments. By the end of the experiment, all five fungal species had reduced the number of SCN cysts in the roots. The lowest number of cysts occurred on plants inoculated with the fungus Funneliformis mosseae. These averaged 10 cysts per plant. Soybean plants that were not inoculated with fungi accumulated 75 or more cysts per plant.

"Each cyst may contain hundreds of nematode eggs," Hartman said.

Further experiments with F. mosseae revealed that exposure to the fungus reduced the number of juvenile nematodes on the plants by more than half.

"We found that as early as seven days after inoculation, roots that were inoculated with F. mosseae were colonized with significantly fewer nematode juveniles," Pawlowski said.

"To see if this interaction and suppression might occur even earlier, we incubated SCN eggs in sterile water alone, with fungal spores or with exudates of the fungal spores. These exudates are microbes and molecules secreted by the spores," she said.

This experiment revealed that the fungal spores and their exudates undermine nematode egg hatching, she said.

"If we can find out what function or compound from the fungi is suppressing egg hatching, that could potentially be a useful nematicide," Pawlowski said.

In recent years, scientists have conducted more than 100 clinical trials in the hopes of finding new indicators capable of diagnosing Alzheimer's disease prior to the manifestation of clinical symptoms such as memory loss. Though MBI, characterized by changes in the normal patterns of behaviour in the elderly, had already been suggested to be an indicator, its role had not yet been validated.

In a recent paper published in Alzheimer's and Dementia, Firoza Lussier, in collaboration with the Alzheimer's Disease Research Unit of the McGill University Research Centre for Studies in Aging, found that MBI may very well give important clues about the early stages of dementia.

Connection between cognitive and non-cognitive symptoms

In order to verify MBI's association to the early stages of Alzheimer's disease, the researchers used imaging techniques to measure amyloid plaque deposits - a protein at the core of Alzheimer's disease - in the brains of nearly 100 cognitively healthy elderly individuals with varying degrees of MBI from the Translational Biomarkers in Aging and Dementia (TRIAD) cohort.

"The unique design of the McGill TRIAD cohort allows young scientist like Firoza to discover the impact of diseases in which specific proteins have become abnormal on human behavior, " says Dr. Pedro Rosa-Neto, Director of the McGill University Research Centre for Studies in Aging.

This is the first time a research team investigates the relationship between MBI and biomarkers of Alzheimer's disease in elderly individuals.

"We found that the presence and severity of MBI in these cognitively healthy individuals was strongly associated with the presence of amyloid plaques in the brain, which is one of the first pathological changes in early stages of Alzheimer's," says Firoza Lussier, who is a master's student in McGill's Integrated Program in Neuroscience.

Using the MBI as a prediction tool

It has been noted that MBI could potentially serve as an interesting proxy for clinicians to diagnose Alzheimer's disease before the onset of symptoms. This could be done with the help of the Mild Behavioural Impairment Checklist (MBI-C), an instrument used to codify mental disorder symptoms attributable to diseases of the nervous system in pre-dementia populations.

"This is an important study because it may help identify people who are at a higher risk of progression of Alzheimer's disease by employing a user-friendly clinical scale developed in Canada by Dr Zahinoor Ismail, and already available world-wide," adds Dr. Serge Gauthier, Director of the Alzheimer Disease and Related Disorders Research Unit.

Lussier and her colleagues now hope to conduct longitudinal imaging studies to confirm whether MBI is predictive of changes in Alzheimer's disease biomarkers.

The ability to generate light pulses of sub-femtosecond duration, first demonstrated some 20 years ago, has given rise to an entirely new field: attosecond science and technology. Table-top laser systems have emerged that enable studies that for decades were but a distant dream --- to follow, image and characterise electronic processes in atoms, molecules and solids on their natural, attosecond timescales. The laser systems that make such studies possible typically operate in the extreme ultraviolet spectral band. There has long been a push to achieve higher photon energies though. Of particular interest is the 'water window', occupied by soft x-ray radiation with wavelengths between 2.2 and 4.4 nm. That spectral window owes its name, and importance, to the fact that at those frequencies, photons are not absorbed by oxygen (and hence by water), but they are by carbon. This is ideal for studying organic molecules and biological specimens in their natural aqueous environment. Today, a handful of attosecond sources spanning this frequency range exist, but their applicability is limited by relatively low repetition rates of 1 kHz or below, which in turn means low count rates and poor signal-to-noise ratios. Writing in Optica, Justinas Pupeikis and colleagues in the Ultrafast Laser Physics group of Prof. Ursula Keller at the Institute for Quantum Electronics report now an essential leap to overcome the limitations of the prior sources. They present the first soft-x-ray source that spans the full water window at 100 kHz repetition rate --- a hundredfold improvement compared to the state-of-the-art sources.

A boost in technological capability

The bottleneck in producing soft x-rays at high repetition rates has been the lack of suitable laser systems to drive the key process underlying attosecond-pulse generation in table--top systems. That process is known as high-harmonic generation, and it involves an intense femtosecond laser pulse interacting with a target, typically an atomic gas. The nonlinear electronic response of the target then causes the emission of attosecond pulses at an odd-order multiple of the frequency of the driving laser field. To ensure that that response contains x-ray photons spanning the water-window range, the femtosecond source has to operate in the mid-infrared range. Also, it has to deliver high-peak-power pulses. And all of that at high repetition rates. Such a source did not exist so far.

Pupeikis et al. took up the challenge and systematically improved a layout they had already explored in earlier work, based on optical parametric chirped pulse amplification (or OPCPA for short). They had established before that the approach is promising with a view to realizing high-power mid-infrared sources, but substantial improvements were still needed to reach the performance required for the high-harmonic generation of x-ray photons in the water window. In particular, they pushed the peak power from previously 6.3 GW to 14.2 GW, and they reached an average power of 25 W for pulses just a bit longer than two oscillations of the underlying optical field (16.5 fs). The peak power demonstrated is comfortably the highest reported to date for any high-repetition-rate system with a wavelength above 2 μm (see the figure, panel a).

Ready for the x-ray room

With this level of performance at their disposal, the team was ready for the next stage, frequency upconversion through high-harmonic generation. For that, the output beam of the OPCPA was routed via a periscope system to another laboratory more than 15 m away, to accommodate for local lab-space constraints. There, the beam met a helium target, kept at a pressure of 45 bar. Such high pressure was necessary for phase-matching between the infrared and the x-ray radiation, and thus optimal energy-conversion efficiency.

All pieces carefully put in place, the system indeed delivered. It generated coherent soft x-ray radiation extending to an energy of 620 eV (2 nm wavelength), covering the full water window --- a stand-out achievement relative to other high-repetition-rate sources in this frequency range, see panel b of the figure.

A window of opportunity

This demonstration opens up a vast spectrum of fresh opportunities. Coherent imaging in the water-window spectral region, highly relevant for chemistry and biology, should be possible with a compact setup. At the same time, the high repetition rate available helps, for instance, addressing the limitations due to space-charge formation which plague photoemission experiments with pulsed sources. Moreover, the 'water window' comprises not only the K-edges of carbon, nitrogen and oxygen, but also the L- and M-edges of a range of metals, which can now be studied with higher sensitivity or specificity.

With such bright prospects, the realization of the source now presented heralds the beginning of the next generation of attosecond technology, one where experimentalists for the first time can make combined use of high repetition rates and high photon energies. An attosecond beamline designed to exploit these new capabilities is currently under construction in the Keller lab.

KNOXVILLE, Tenn.--Researchers at the University of Tennessee Institute of Agriculture's Amphibian Disease Laboratory are working to understand--and hopefully get ahead of--highly contagious pathogens affecting amphibians in Europe and Asia. One of the pathogens of interest is Batrachochytrium salamandrivorans, or Bsal.

Managed by Debra Miller and Matt Gray, professors in the Department of Forestry, Wildlife and Fisheries, the Amphibian Disease Laboratory is investigating disease management strategies for if, and possibly, when, Bsal makes its way to the United States through international animal trade or other means. Recent findings by Daniel Malagon, former undergraduate student working in the lab, show promising information for disease management of Bsal.

Using existing data from controlled experiments and computer simulations, Malagon found that host contact rates and habitat structure affect transmission rates of Bsal among eastern newts, a common salamander species found throughout eastern North America. Simply put, the higher the population density of the salamanders, the greater the rate of Bsal transmission. Malagon also found that adding habitat complexity, thereby separating the salamanders from each other, causes transmission rates to drop. These findings are similar to the results being observed when human populations follow the COVID-19 mitigation guidelines seen across the globe today.

Malagon's academic advisor Matt Gray, who is also the chair of the North American Bsal Task Force, states, "Wildlife and humans pathogens are quite similar. In fact, Daniel's results support the strategy of social distancing being used to mitigate the COVID-19 outbreaks. By reducing host density in newts or humans, contact rates, and therefore transmission, are reduced. Habitat structure also reduced contact rates of newts, so transmission is curtailed in more complex habitats. This may be analogous to COVID-19 environments. A person may be more likely to become infected in a homogenous movie theater compared to walking through a heterogeneous forest, even if density of people was the same."

This research will support disease mitigation strategies for amphibians and could provide support for infectious disease recommendations for humans as well. "Our results suggest efficient pathogen spread in populations of highly susceptible salamander species, like the eastern newt. These populations will likely be negatively impacted if Bsal reaches North America. We hope our findings will help inform policy and management strategies to prevent the introduction of Bsal into North America," added Malagon.

This research is in support of Gray and Miller's National Science Foundation Project #181450, and the paper with these findings was recently published online by Nature Scientific Reports. Malagon, who is now a doctoral student at Clemson University, was supported in this research by the UT Knoxville College Scholars Program. Co-authors on the paper include Luis Melara of the Department of Mathematics, Shippensburg University; Olivia Prosper, formerly with the Department of Mathematics, University of Kentucky, and now with UT Knoxville; Suzanne Lenhart, Department of Mathematics, UT Knoxville; Jim Fordyce, Department of Ecology and Evolutionary Biology, UT Knoxville; and Davis Carter and Anna Peterson, Center for Wildlife Health, Department of Forestry, Wildlife and Fisheries, UT Institute of Agriculture.

Miller also holds an appointment in the Department of Biomedical and Diagnostic Sciences at the UT College of Veterinary Medicine and is currently serving as the interim director of the UT One Health Initiative. Announced in January, the UT One Health Initiative seeks fundamental answers to issues that address the inextricably linked health of humans, animals, plants and the environment as a whole.

New research suggests that large-scale environmental factors influence the size of one of the ocean's most abundant forage species. Recently, scientists from LSU, NOAA, the University of Southern Mississippi and the University of Maryland Center for Environmental Science evaluated large-scale ecosystem dynamics influencing growth of menhaden in the Gulf of Mexico and the Atlantic Ocean. They found that anthropogenic influences affected menhaden in the Atlantic more than in the Gulf, where environmental factors were the more dominant predictors of growth.

Menhaden are used primarily for the production of fishmeal and fish oil, and small quantities are used for bait. According to NOAA's 2018 Fisheries of the United States report, menhaden ranked number two by volume, after Alaska pollock, on the list of major U.S. domestic species "landed," or caught and brought to port. More than 1.5 billion pounds of menhaden were landed in that year. Menhaden ranked number 10 by value of the landings, totaling more than $160 million. In addition to their commercial value, menhaden are critically important components of their food webs.

According to Steve Midway, lead author and assistant professor in LSU's Department of Oceanography & Coastal Sciences, "They're sort of the classic forage species--meaning they provide a really important link in marine food webs. They are not exerting any kind of population pressure on any other fish species because they're not eating any other fish species. But, other fish species eat them. So, they support the higher levels of the food web and ecosystem."

The scientists evaluated the coast-wide annual growth of Atlantic menhaden (Brevoortia tyrannus) and Gulf menhaden (Brevoortia patronus) during the past 50-60 years. They found that, in the Atlantic, fishing pressure was the primary influence on the length-at-age (used to determine how rapidly a fish grows in a given period) at the time of harvest. By contrast, Gulf menhaden growth was influenced primarily by environmental conditions: a combination of wind and the Atlantic Multi-Decadal Oscillation, or AMO--a climate cycle that affects the sea surface temperature.

In the Atlantic, they found that easterly winds correlated positively with menhaden growth in the northern portion of the East Coast; however, while wind and AMO significantly influenced menhaden growth, the primary influence was fishing pressure. The more menhaden that were landed, the more likely they were to grow larger and faster. From this data, the scientists hypothesize that the population reduction caused by commercial fishing may reduce competition among menhaden and allow individual fishes to have access to more resources that would allow them to grow larger at a faster rate.

In the Gulf, the researchers found that northerly winds reduced the growth of menhaden. They think the reason for this may be that the northerly winds interacted with freshwater from the Mississippi and Atchafalaya Rivers and displaced that water further offshore, negatively affecting the saltwater-preferring menhaden.

Currently, these environmental factors are not taken into account when determining fisheries assessment outcomes, according to Amy Schueller, co-author of the paper and research fish biologist in NOAA's Southeast Fisheries Science Center; however, this research could be used as predictive tool by fisheries management agencies to forecast menhaden growth each season and determine management strategies in the future.

"[T]his study allowed us to get a better handle on the way the menhaden population responds to landings vs environmental conditions which should feed into managers' thinking about how much effect their regulations can have on these stocks and how these stocks might respond," said Geneviève Nesslage, co-author and assistant research professor at the University of Maryland Center for Environmental Science.

Toronto - Whether it's blocking traffic outside a Donald Trump rally or preventing women from entering an abortion clinic, social activists take a risk when they choose extreme tactics to make their point.

New research has found that social change advocates face an "activist's dilemma." While extreme actions can bring more attention to a cause than moderate ones, they are more likely to diminish support, even among natural sympathizers, the study found.

Finding the sweet spot between the two is tricky, acknowledged Matthew Feinberg, an assistant professor of organizational behaviour and human resource management at the University of Toronto's Rotman School of Management.

"We were curious if this dilemma exists, and if so, we wanted to more deeply understand how social movements might be able to overcome it," said Prof. Feinberg.

The researchers conducted six separate experiments in which participants were presented with different protest scenarios, including moderate and extreme protest actions at a Donald Trump campaign event, against anti-Black police violence, abortion activities, for and against gun control and in defense of animal rights.

Study participants were more likely to emerge with a negative view of the cause when a protest used extreme actions - even when participants were already politically or socially sympathetic to its message. Extreme actions were anything perceived to be highly disruptive or to cause harm to others, such as physical violence or threatening language.

Participants tended to feel that extreme behaviour crossed a line into immorality, which the researchers believe is what leads to the loss of support. Observers are less able to connect emotionally with the protest, leading them to identify less with the movement and back away from the cause.

"We found extreme anti-Trump protest actions actually led people to not only dislike the movement and support the cause less, but to be willing to support Trump more," said Prof. Feinberg. "It was almost like a backlash."

Previous studies have been mixed about the impact of extreme action. Some have shown that it can influence large institutions to change and bring more attention to a cause. Other research has suggested non-violent campaigns are twice as likely as violent ones to achieve their goals.

It means that activists should be clear about their objectives and carefully weigh their options for the best ways to achieve them, the researchers say. A movement with relatively low profile might consider more extreme action when it's starting out, becoming more moderate later to retain and build support.

"By no means are we trying to be negative towards activism," said Prof. Feinberg. "We're actually big fans of social movements and that's the reason we study them."

Emitting light from silicon has been the 'Holy Grail' in the microelectronics industry for decades. Solving this puzzle would revolutionize computing, as chips will become faster than ever. Researchers from Eindhoven University of Technology now succeeded: they have developed an alloy with silicon that can emit light. The results have been published in the journal Nature. The team will now start creating a silicon laser to be integrated into current chips.

Every year we use and produce significantly more data. But our current technology, based on electronic chips, is reaching its ceiling. The limiting factor is heat, resulting from the resistance that the electrons experience when traveling through the copper lines connecting the many transistors on a chip. If we want to continue transferring more and more data every year, we need a new technique that does not produce heat. Bring in photonics, which uses photons (light particles) to transfer data.

In contrast to electrons, photons do not experience resistance. As they have no mass or charge, they will scatter less within the material they travel through, and therefore no heat is produced. The energy consumption will therefore be reduced. Moreover, by replacing electrical communication within a chip by optical communication, the speed of on-chip and chip-to-chip communication can be increased by a factor 1000. Data centers would benefit most, with faster data transfer and less energy usage for their cooling system. But these photonic chips will also bring new applications within reach. Think of laser-based radar for self-driving cars and chemical sensors for medical diagnosis or for measuring air and food quality.

Dropping electron emits a photon

To use light in chips, you will need a light source; an integrated laser. The main semiconductor material that computer chips are made of is silicon. But bulk silicon is extremely inefficient at emitting light, and so was long thought to play no role in photonics. Thus, scientists turned to more complex semiconductors, such as gallium arsenide and indium phosphide. These are good at emitting light but are more expensive than silicon and are hard to integrate into existing silicon microchips.

To create a silicon compatible laser, scientists needed to produce a form of silicon that can emit light. That's exactly what researchers from Eindhoven University of Technology (TU/e) now succeeded in. Together with researchers from the universities of Jena, Linz and Munich, they combined silicon and germanium in a hexagonal structure that is able to emit light. A breakthrough after 50 years of work.

Hexagonal structure

"The crux is in the nature of the so-called band gap of a semiconductor," says lead researcher Erik Bakkers from TU/e. "If an electron 'drops' from the conduction band to the valence band, a semiconductor emits a photon: light." But if the conduction band and valence band are displaced with respect to each other, which is called an indirect band gap, no photons can be emitted - as is the case in silicon. "A 50-year old theory showed however that silicon, alloyed with germanium, shaped in a hexagonal structure does have a direct band gap, and therefore potentially could emit light," says Bakkers.

Shaping silicon in a hexagonal structure, however, is not easy. As Bakkers and his team master the technique of growing nanowires, they were able to create hexagonal silicon in 2015. They realized pure hexagonal silicon by first growing nanowires made from another material, with a hexagonal crystal structure. Then they grew a silicon-germanium shell on this template. Elham Fadaly, shared first author of the Nature paper: "We were able to do this such that the silicon atoms are built on the hexagonal template, and by this forced the silicon atoms to grow in the hexagonal structure."

Silicon laser

But they could not yet make them to emit light, until now. Bakkers team managed to increase the quality of the hexagonal silicon-germanium shells by reducing the number of impurities and crystal defects. When exciting the nanowire with a laser, they could measure the efficiency of the new material. Alain Dijkstra, also shared first author of the paper and responsible for measuring the light emission: "Our experiments showed that the material has the right structure, and that it is free of defects. It emits light very efficiently."

Creating a laser now is a matter of time, Bakkers thinks. "By now we have realized optical properties which are almost comparable to indium phosphide and gallium arsenide, and the materials quality is steeply improving. If things run smoothly, we can create a silicon-based laser in 2020. This would enable a tight integration of optical functionality in the dominant electronics platform, which would break open prospects for on-chip optical communication and affordable chemical sensors based on spectroscopy."

In the meantime his team is also investigating how to integrate the hexagonal silicon in cubic silicon microelectronics, which is an important prerequisite for this work. This research project has been funded by the EU project SiLAS, coordinated by TU/e professor Jos Haverkort.

The tragic COVID-19 pandemic is creating new awareness regarding the importance of breathing problems, pneumonia and ventilators. What many people don't realize is that without anesthesia and operating room ventilators, the millions of surgeries normally performed each year in the U.S. would be impossible.

Being "put under" anesthesia is accomplished with a cocktail of drugs used to render a patient unconscious and pain free with their muscles relaxed, enabling safe surgeries. As minimally invasive techniques such as laparoscopic surgery have gained widespread use, keeping a patient's muscles relaxed and preventing movement during surgery has become increasingly important. A breathing machine, known as a ventilator, is used to help the surgical patient breathe during anesthesia while their muscles are relaxed.

For decades, surgical anesthesia has relied on the drug neostigmine, considered an essential medicine by the World Health Organization, to reverse this muscle relaxation when waking a patient following a procedure. However, researchers have suspected that some of the more serious post-surgical complications, such as pneumonia and respiratory failure, are the result of residual effects of the muscle relaxants.

"For example, pneumonia may be related to the inability to take a deep breath or cough due to residual muscle weakness," says Sachin Kheterpal, M.D. MBA, professor of anesthesiology at U-M Medical School. Five percent of patients undergoing major non-cardiac inpatient surgery have major pulmonary complications, resulting in $100,000 in additional medical costs per patient, he notes.

In 2017, the U.S. Food and Drug Administration approved a new drug called sugammadex designed to reverse the effect of muscle relaxants in a different way. In a new study, Kheterpal and a team of researchers at Michigan Medicine compared the rates of serious pulmonary complications in patients who received neostigmine versus those who received sugammadex. They found the newer drug was associated with significantly reduced rates of these complications.

How sugammadex works

The improvement may lie in the difference between how the drugs work. In order for a muscle to move, a signal is sent from the brain down a nerve to that muscle. At the end of the nerve is released acetylcholine, a neurotransmitter that causes the muscle to contract. Acetylcholine receptors are located in all voluntary muscle. Muscle relaxing drugs, such as rocuronium, work by blocking muscle receptors to this nerve signal.

To put it another way, says Kheterpal, "muscle paralysis drugs work sort of like earplugs on nerve endings. If acetylcholine is a loud noise in this analogy, neostigmine increases how much acetylcholine is available to amplify the signal, similar to yelling louder to be heard through the earplugs." Sugammadex, on the other hand, "takes the molecule of rocuronium out of the muscle receptor, removing the earplugs." As a result, he says, there are fewer side effects throughout the body and a more complete reversal of the muscle relaxant effect.

For the observational study, the team compared the medical records of 22,856 patients receiving sugammadex to 22,856 patients receiving neostigmine in 12 hospitals in the U.S. The data for the study came from the Multicenter Perioperative Outcomes Group, a national consortium of more than 50 hospitals across 30 states, which Kheterpal and Michigan Medicine lead.

Bridion, which is the brand name for the drug sugammadex, is currently more expensive than neostigmine and typically reserved for sicker patients or patients who may have risks associated with increased acetylcholine. To account for the effect of the different patient populations, the team matched people who were the same age, had the same medical conditions, and who were having the same type of surgery before and after sugammadex became available in 2017.

"When we looked at documentation of respiratory failure or pneumonia, we saw a 37% decrease across all pulmonary complications and 55 percent decrease in respiratory failure," says Kheterpal. "This is a dramatic decrease in rates of complications."

He notes that some of the limitations of the study include the fact that it was not a randomized controlled trial and it didn't include many young healthy patients or certain types of surgeries, such as emergency surgery. "The decision for each patient has to be left up to the providers. But in many practices, neostigmine is no longer used in high risk patients or procedures," he says.

There is evidence that climate change affects both the quantity and quality of food production, reducing food security, and nutrition intake. In developing countries, where the agricultural sector dominates the economy, the impacts of the changing climate on the agricultural supply chain will substantially hinder economic growth and well-being of the local communities.

A recent study co-authored by researchers of the CMCC Foundation - Euro-Mediterranean Center on Climate Change analyses the case of Uganda, a Sub-Saharan African country already struggling with malnutrition and susceptible to the effects of climate change, with about 80 per cent of the population depending on rain-fed agriculture for their livelihood. The analysis sheds light on an important but understudied linkage between climate change and labor supply through food consumption.

Using longitudinal micro survey data from Uganda combined with high-resolution climatic data, the study aims to fill the gap in the existing literature by empirically investigating both the direct effect of climatic shocks on labor supply (defined as the number of hours worked per week for a person) and the indirect effect through variation in dietary intakes due to a warmer environment.

"For the first time, we have provided empirical evidence linking climate change, nutrition and labor supply", explains Shouro Dasgupta researcher at CMCC and RFF-CMCC European Institute on Economics and the Environment (EIEE). "We know that climate change will have an impact on nutrition, and that nutrition plays a key role in improving labor productivity and boosting economic growth in regions where the labor force consists mainly of low-skilled and undernourished individuals. Our study shows that, as temperature increases, initially labor supply does increase; in a mild environment, people can work more hours per week. But beyond a weekly temperature threshold of 21.3°C, number of hours per worker declines due to heat stress".

Food intake requirement is lower in the intermediate ranges of temperature, as supported by the medical literature, due to lower energy requirements, while both low as well as high temperatures lead to a higher calorie intake. Temperature has a non-linear (instead, a U-shaped) relationship with calories intake.

"At both extreme ranges of temperature (very cold temperatures and very hot temperatures), the human body needs more energy, and thus more food, to regulate its temperature", explains Dasgupta. "Thanks to our study, there is now empirical evidence available for the first time of this energy balance equation, as we observed the real weekly calories intake of households in relation to the weekly temperature". This shows that a warmer climate can also have an indirect effect on nutrition by increasing the need of calories intake.

In addition, results suggest that a 10 per cent increase in calories consumption leads to an increase in labor supply of almost one hour per week. "The repeated household surveys allowed us to separate two effects of weather/climate on household economic outcomes: that of short-term weather on hours worked and the last year's climate on agricultural output and hence food supply. The results suggest that increased global warming can have a significant detrimental impact on both labor supply and food security" affirms Johannes Emmerling, senior researcher at CMCC Foundation and head of the Integrated Assessment Modeling Unit at EIEE.

"We were able to model the economic behavior of the Ugandan households and show how the drop in labor productivity due to rising temperatures will be amplified by an increase in demand for food consumption" explains Soheil Shayegh, researcher at CMCC Foundation and EIEE. Researchers used these empirical results to parametrize an Overlapping Generations Model to estimate the long-term impacts of future climate change - if unmitigated - are projected on food consumption, human capital development, and social welfare. Results show that in Uganda, low-skilled labor will increase due to an increasing demand for agricultural products by the end of the century.

An increase in number of low-skilled laborers, coupled with climate change impacts on sectoral productivity and labor supply, leads to a significant drop in total economic output and reduces output per adult by 20 per cent in the last part of the century under severe climate change projections.

"Our results can be used to identify areas that are at risk and to promote or encourage specific adaptation strategies" concludes Dasgupta. "We know that households - and especially rural households - will have to undertake a variety of climate change adaptation strategies to maintain their livelihoods. Our results can be used by policymakers to identify and use specific adaptation strategies". Suggested strategies include changing the planting time of crops, use more hit and drought resilient types of crops, practicing conservation techniques, fertilizer use, irrigation, and income diversification.