Earth

Exopolysaccharides (EPS) are surface-exposed carbohydrates that surround and protect bacteria and are involved in biofilm formation, cell-to-cell interactions, immune evasion, and pathogenesis. The structures and compositions of EPS synthesized by different bacteria are highly diverse and therefore a molecular fingerprint.

EPS also plays an important role for bacterial colonization and symbiosis with plants. Nitrogen-fixing soil bacteria (rhizobia) are recognized on the basis of their EPS when colonizing plant roots, judged compatible or incompatible by their legume host and allowed or denied access accordingly. The single-pass transmembrane Exopolysaccharide receptor 3 (EPR3) is responsible for monitoring EPS.

"To gain a deeper understanding of the function of this receptor, we needed to know what it looks like", says Jaslyn Wong, who conducted this research at Aarhus University. Unfortunately, attempts to determine the structure of the ligand-binding portion of EPR3 remained unsuccessful for years, but a breakthrough was finally achieved by using llama-derived nanobodies to obtain a crystal of the receptor.

The structure revealed that EPR3 stands out from other members of the so-called LysM receptor kinases. EPR3 deviates in its ligand-binding domain from the canonical members of this receptor family and has a fold that is unique and novel for carbohydrate binding proteins.

"This is a good example of how a structure changes our view on the biology", says Kasper Røjkjær Andersen. "We are now able to demonstrate the existence of a completely new and structurally unique class of carbohydrate receptors and find that this class is conserved in the entire plant kingdom. We did not know this before we obtained the structure and this opens for a lot of exciting biology to understand the role of the receptor".

Jaslyn Wong adds: "Research on EPS receptors is still in its infancy, and I am excited about how this knowledge could be used and its potential implications on shaping microbiota for more sustainable agriculture".

Major Depressive Episodes Far More Common than Previously Believed, New Study Finds

The number of adults in the United States who suffer from major depressive episodes at some point in their life is far higher than previously believed, a new study by the Yale School of Public Health finds.

National survey data currently shows that approximately 17% of women and 10% of men report having a history of major depressive episodes (MDEs) in their lifetimes. But these data are subject to "recall error," or the tendency of people to forget or misreport their health histories when taking a survey.

Researchers led by Jamie Tam, Ph.D., assistant professor in the Department of Health Policy and
Management, created a simulation model to generate corrected estimates of lifetime depression. They found that the proportion of U.S. adults who have had MDEs is actually closer to 30% of women and 17% of men after factoring in recall error.

"Major depressive episodes are far more common than we thought," said Tam. "Our model shows that the probability of someone having a first major depressive episode is especially high during adolescence. We also know from other research that having a first major depressive episode increases the likelihood you'll have a second one. This means that anything we can do to prevent or treat episodes among young people could lead to larger health benefits over the course of their life."

The findings are published in the American Journal of Preventive Medicine.

A major depressive episode is defined as a period of two weeks or longer in which a person experiences feelings of intense sadness and hopelessness, fatigue, weight gain or weight loss, changes in sleeping habits, loss of interest in activities and thoughts of suicide or attempts at suicide. These persistent symptoms cannot be easily changed, even if they are contradictory to a person's circumstances. Depressive episodes typically recur periodically in people diagnosed with major depression.

The study shows that mental health programs that screen for, prevent and treat depression could benefit a much larger segment of the population than previously thought, Tam said.

"If you think about chronic health conditions like heart disease, we do a lot to identify people who might be at risk for additional health events like heart attacks because that group would benefit from maintenance treatment and clinical monitoring," Tam said. "We don't do such a great job when it comes to mental health conditions. So, if we're able to assess how many people actually have histories of depression, that also tells us that more people are at risk of experiencing more depressive episodes."

The researchers also found that older adults are especially likely to under-report their history of having depressive symptoms. Among adults 65 years and older, underreporting for depression was as high as 70%. Older adults often experience what is referred to as "minor depression," where they still report significant depressive symptoms but don't always meet clinical requirements for major depression. Tam said there may be a tendency for older adults to downplay negative experiences of depression from when they were younger, classifying them as "growing pains" rather than major depression.

"Unfortunately, many people with depression or with histories of depression don't access, or don't have access to, treatment or support," Tam said. "There's a broader problem in our society of mental health not receiving the same attention and investment of resources compared to physical health conditions."

Tam wrote the paper with colleagues from the University of Michigan School of Public Health.

A Chinese-Australian collaboration has demonstrated for the first time that interlayer coupling in a van der Waals (vdW) material can be largely modulated by a protonic gate, which inject protons to devices from an ionic solid.

The discovery opens the way to exciting new uses of vdW materials, with insertion of protons an important new technique, now available for the wider 2D materials research community.

The study was led by FLEET researchers at RMIT, in an ongoing collaboration with FLEET partner organisation High Magnetic Field Laboratory, Chinese Academy of Sciences (CAS).

TUNING INTERLAYER FORCES IN VDW MATERIALS

Van der Waals materials, of which graphite is the most famous, are made of many 2D layers held together by weak, electrostatic forces.

Individual layers of vdW materials can be isolated individually, such as the famous Scotch tape method of producing graphene, or stacked with other materials to form new structures.

"But the same weak interlayer forces that make vdW materials so easy to separate also limit these materials' applications in future technology," explains the study's first author, FLEET Research Fellow Dr Guolin Zheng.

Stronger interlayer coupling in vdW materials would significantly increase potential use in high-temperature devices utilising quantum anomalous Hall effect, and in 2D multiferroics.

The new RMIT-led study demonstrated that coupling in a vdW material, Fe3GeTe2 (FGT) nanoflakes, can be largely modulated by a protonic gate.

With the increase of the protons among layers, interlayer magnetic coupling increases.

"Most strikingly, with more protons inserted in FGT nanoflakes at a higher gate voltage, we observed a rarely seen zero-field cooled exchange bias with very large values," says co-author A/Prof Lan Wang.

The successful realization of both field-cooled and zero-field cooled exchange bias in FGT implies the interlayer coupling can be largely modulated by gate-induced proton insertion, opening the road to many applications of vdW materials requiring strong interface coupling.

Behavioral and nicotine replacement therapies offered together can help people who are incarcerated quit smoking, according to Rutgers researchers.

The study published in the American Journal of Men's Health, found that the combination of group-based tobacco dependence treatment and nicotine replacement therapy was an effective and feasible option to reduce tobacco dependence among men who were incarcerated and transgender women who face significant barriers to accessing smoking cessation treatment services.

"Smokers who are incarcerated, similar to other marginalized populations who smoke, lack the necessary skills to quit and have limited access to treatment options," said Pamela Valera, an assistant professor in the Department of Urban-Global Public Health at the Rutgers School of Public Health. "Without smoke cessation resources and treatment, only 5 percent of those who quit will achieve long-term success."

In the United States, people who are incarcerated smoke tobacco products, including cigarettes, at disproportionately higher rates than the general adult population, which can be attributed to behavioral health conditions and mental health symptoms. People who are incarcerated are likely to use tobacco products. They use tobacco products to cope with chronic and daily stress caused by missing family and friends, lack of freedom, prison lockdowns, long periods of boredom, interaction with correctional officers and medical staff, and stressful events due to incarceration itself.

The study -- which took place over six weeks -- included 177 male and transgender female inmates from seven prisons. Inmates over age 18 who smoked at least five cigarettes per day over the previous week received nicotine replacement therapy in the form of patches and weekly group smoking cessation treatment. The treatment included sessions on cognitive social learning, lifestyle changes, coping, healthy decision-making, maintenance and relapse prevention, and long-term abstinence.

Inmates who completed the six-week program reduced tobacco smoking or quit all together, suggesting the program may be promising for future larger-scale studies.

"By providing inmates the space to share their experiences surrounding nicotine withdrawal and nicotine dependence, many were able to learn coping strategies, identify their triggers, express their emotions with stressors while incarcerated and become supporters of each other's quit journey," said Nicholas Acuna, a Rutgers School of Public Health alumnus.

A team of scientists, led by UK Met Office, has achieved a scientific breakthrough allowing the longer-term prediction of North Atlantic pressure patterns, the key driving force behind winter weather in Europe and eastern North America. CMCC scientists Panos Athanasiadis, Alessio Bellucci, Dario Nicolì and Paolo Ruggieri from CSP – Climate Simulation and Prediction Division were also involved in this study.

Published in Nature, the study analysed six decades of climate model data and suggests decadal variations in North Atlantic atmospheric pressure patterns (known as the North Atlantic Oscillation) are highly predictable, enabling advanced warning of whether winters in the coming decade are likely to be stormy, warm and wet or calm, cold and dry.

However, the study revealed that this predictable signal is much smaller than it should be in current climate models. Hence 100 times more ensemble members are required to extract it, and additional steps are needed to balance the effects of winds and greenhouse gases. The team showed that, by taking these deficiencies into account, skillful predictions of extreme European winter decades are possible.

Lead author Dr Doug Smith, who heads decadal climate prediction research and development at the Met Office Hadley Centre, said: “The message from this study is double-edged: climate is much more predictable than we previously thought, but there is a clear need to improve how models simulate regional changes.”

Advance warning of severe winter weather is imperative to those who make risk-based decisions over longer timescales.For example, better forecasts can help the Environment Agency plan water management and flood defences, insurance companies plan for the changing risks, the energy sector to mitigate against potential blackouts and surges, and airports plan for potential disruption.

Improving model simulations will enhance the countries’ response, resilience and security against the effects of extreme weather and climate change – influencing future policy decisions to protect people’s lives, property and infrastructure.

New, first-of-its-kind research from the University of Colorado Boulder shows that climate change is driving increasing amounts of freshwater in the Arctic Ocean. Within the next few decades, this will lead to increased freshwater moving into the North Atlantic Ocean, which could disrupt ocean currents and affect temperatures in northern Europe.

The paper, published July 27, 2020 in Geophysical Research Letters, examined the unexplained increase in Arctic freshwater over the past two decades and what these trends could mean for the future.

"We hear a lot about changes in the Arctic with respect to temperature, how ecosystems and animals are going to be affected," said Rory Laiho, co-author and PhD student in atmospheric and oceanic sciences. "But this particular study gives an added perspective on what's happening physically to the ocean itself, which then can have important implications for ocean circulation and climate."

Since the 1990s, the Arctic Ocean has seen a 10% increase in its freshwater. That's 2,400 cubic miles (10,000 cubic kilometers), the same amount it would take to cover the entire U.S. with 3 feet of water.

The salinity in the ocean isn't the same everywhere, and the Arctic Ocean's surface waters are already some of the freshest in the world due to large amounts of river runoff.

This freshwater is what makes sea ice possible: it keeps cold water at the surface, instead of allowing this denser liquid to sink below less dense, warm water. In this way, the Arctic Ocean is much different than other oceans. But as more freshwater exits the Arctic, this same stabilizing mechanism could disrupt the ocean currents in the North Atlantic that moderate winter temperatures in Europe.

Such disruptions have happened before, during the "great salinity anomalies" of the 1970s and 80s. But these were temporary events. If too much cold freshwater from the Arctic continuously flows into the North Atlantic, the ocean turnover could be disrupted more permanently.

Ironically, this would mitigate the impacts of global warming during winter in northern Europe for a while. But disrupting the ocean currents could have negative effects for climate long-term and on the North Atlantic's ecosystems.

A signal in the noise

The main mission of the research for Alexandra Jahn, lead author of the new study and assistant professor in the Department of Atmospheric and Oceanic Sciences and the Institute of Arctic and Alpine Research, and her graduate student, Laiho, was to differentiate between natural variability cycles in Arctic freshwater amounts and climate change's impact. They examined the results from an ensemble of models run from 1920 to 2100.

"When we look at all the simulations together, we can see if they all do the same thing. If so, then that's due to a forced response," said Jahn. "If those changes are big enough so they could not occur without increasing greenhouse gases in the model simulations, that's what we call the emergence of a clear climate change signal. And here we see such clear climate change signals for the Arctic freshwater during the current decade."

Their results showed that Nares Strait, which runs between Greenland and Canada and is the most northern gateway between the Arctic and more southern oceans--will be the first place to see a freshwater export increase attributable to climate change in the next decade. Other straits farther south and east, including Davis and Fram straits, will be next to show this signal.

The researchers also ran the models through different emissions scenarios to see if these changes will be affected by humans' emissions choices in the next few decades. They looked at the "business as usual" (over 4 degrees Celsius warming by the end of the century) scenario and what would happen if humans limited warming to 2 degrees Celsius, the upper end of IPCC (Intergovernmental Panel on Climate Change) targets for this century.

They found that the change in freshwater in the Arctic Ocean and the amounts moving through the northern straits were unaffected since they will be subject to an increase in freshwater before the 2040s--and the decisions made globally in the next few decades will not influence them, as these climatic changes are already in motion. But in the second half of this century, the two scenarios diverged, and increases in freshwater amounts were seen in more places in the high-warming scenario than in the low-warming scenario.

"What this work is showing us is that we're probably already experiencing the first of these changes, we just can't tell from the direct observations yet," Jahn said.

All water from the Arctic Ocean eventually ends up in the North Atlantic. But timing is everything. Being able to predict the timing of the emergence of climate change signals will allow scientists to monitor upcoming changes in real time, and better understand how changes in the Arctic Ocean can impact climate worldwide.

"It fills a gap in our current understanding, and helps us ask new questions about what physically is happening in the Arctic," said Jahn.

Supported bimetallic catalysts are an important class of catalysts in heterogeneous catalysis. They can be applied in various fields, such as electrocatalysis, biomass conversion, and hydrogen production.

However, traditional impregnation and immobilization methods for synthesizing supported bimetallic nanoparticles (BNPs) are often uncontrollable, thus creating BNPs with non-uniform particle size, low alloy degree and inhomogeneous distribution on the supports. The result is poor catalytic performance and low metal utilization.

To improve the performance and efficiency of the supported BNPs, Prof. WANG Guanghui and Prof. JIANG Heqing from the Qingdao Institute of Bioenergy and Bioprocess Technology (QIBEBT) of the Chinese Academy of Sciences (CAS), in collaboration with Prof. LIU Jian from the Dalian Institute of Chemical Physics (DICP) of CAS, recently proposed a nanoreactor strategy for scalable synthesis of the supported ultrafine BNPs.

This strategy introduces high-quality seeds (Pd nanoclusters) and Au ions into the nitrogen-doped mesoporous polymer (NMP). The NMP is used as a nanoreactor for the seeded growth of PdAu BNPs in solid state during thermal reduction.

"The synthesized Pd1Au1/4 BNPs are very uniform in diameter with an error of 0.5 nm, and are homogeneously dispersed in the NMP support," said Prof. WANG.

The Pd1Au1/4/NMP sample showed enhanced catalytic performance in formic acid (FA) dehydrogenation compared with the monometallic analogues Pd/NMP and Au/NMP.

"The enhanced activity can be attributed to the electronic interaction between Pd and Au in the Pd1Au1/4 BNPs. In addition, the electronic interaction could be adjusted by changing the composition of PdAu BNPs during synthesis," said Prof. JIANG.

Moreover, the PdAu/NMP product can be molded into a monolith by a pellet press under mild pressure (1.0 bar) without any binders, due to its coral-like structure. The monolith contains abundant macropores which can be of benefit for mass transfer in a liquid reaction.

Notably, the monolith of Pd1Au1/4/NMP still exhibits considerable activity in FA dehydrogenation with a TOF value of 3684 h-1 at 333 K, and can be recycled five times without mass loss and changes in activity.

Many other supported Pd-based BNPs (diameters ranging from 2-3 nm) have also been synthesized using this method, including PdRu, PdCo, PdNi, PdZn, PdAg and PdCu BNPs.

This proposed nanoreactor strategy provides an effective route for synthesizing various supported bimetallic catalysts. These catalysts are promising for applications in green and sustainable catalytic processes.

A study conducted over the past 18 years has found differences between lead exposure effects in young Japanese boys versus girls.

Researchers from the Tohoku University Graduate School of Medicine have been tracking 289 children in Japan since they were in the womb through age 12. They measured lead levels in blood at a prenatal stage and at the age 12, and conducted IQ and linguistic tests.

Lead is a heavy metal known to be toxic to the environment and linked with adverse effects in neurological, gastrointestinal and cardiovascular systems. Even low levels of exposure have been shown to cause neurological and behavioural issues in children. But how much exposure is too much has been unclear, especially during pregnancy.

Existing data suggests that Japanese children have relatively low lead levels (around 1 microgram per decilitre, or 1 μg/dL) compared to the US's action level (5μg/dL), which is used to identify children with blood lead levels higher than average. Other studies showed that a lead level of 2μg/dL or lower can still cause damage to intellectuality. No universal lead threshold determined safe for children is currently available.

"To our knowledge, the health effects of lead exposure at such levels in Japanese children have not been examined," says Associate Professor Nozomi Tatsuta at Tohoku University Graduate School of Medicine.

The researchers found a correlation between boys' reduced cognitive abilities and lead exposure after birth, while their linguistic skills were compromised by both pre and postnatal exposure. Furthermore, they divided the boys' blood samples into four groups by the lead concentration level and found those with higher lead levels also had lower cognitive and language skills. In contrast, there was no significant association between lead exposure and the intellectual capacity of girls. The findings suggest that boys were more susceptible to such effects than girls.

The researchers noted that genetics and the environment also contribute to the cognitive development of children.

Future studies should look further to determine the effects of low lead exposure during a prenatal phase, with a focus on how gender is affected differently by it. Researchers will also need to clarify the way to reduce lead exposure.

Sophia Antipolis, 30 July 2020: In adolescents the use of e-cigarettes doubles the risk of starting to smoke traditional cigarettes, states a position paper published today in the European Journal of Preventive Cardiology, a journal of the European Society of Cardiology (ESC).1

"Vaping is marketed towards teenagers and the tobacco industry uses celebrities to promote it as being healthier than smoking," said senior author Professor Maja-Lisa Løchen of UiT The Arctic University of Norway, Tromsø.

"Legislation on the marketing and sales of e-cigarettes varies enormously between countries," said Professor Løchen. "Action is urgently needed to halt the growing use in young people. The World Health Organization (WHO) states that e-cigarettes are harmful to health."

Studies have reported that e-cigarette use in young people has increased from 5% in 2013 to nearly 25% in 2018. Up to 5% of adults use e-cigarettes, with wide variation between countries.

The position paper of the European Association of Preventive Cardiology (EAPC), a branch of the ESC, focusses on the cardiovascular effects of e-cigarettes - including devices that look like cigarettes and refillable vaporisers that do not look like cigarettes. It calls on regulators to protect young people by limiting sales and advertising and banning sweet flavours which teens believe are less harmful.

Research has shown that e-cigarettes raise blood pressure and heart rate, change the artery walls so that they become stiffer and less elastic, and inhibit the function of blood vessels by damaging their lining. Each of these four effects are risk factors for blood clots and fatty build-up inside artery walls which can cause heart attacks. A study last year found a link between e-cigarettes and heart attacks.

On top of the heart effects, evidence is accumulating that vaping has negative effects on the lungs and is detrimental to the developing foetus during pregnancy. Preliminary research indicates that e-cigarettes could cause cancer.

It's not clear whether e-cigarettes can help people quit smoking, since studies have produced conflicting results. "When these studies are pooled together it does not show that e-cigarettes are more effective than conventional, well-tested stop smoking methods," said Professor Løchen. "In addition, people who use e-cigarettes for smoking cessation often end up being double consumers of both traditional tobacco cigarettes and e-cigarettes."

"E-cigarettes should only be used for smoking cessation if nothing else has worked and the individual is carefully monitored for adverse effects," she added.

Professor Løchen concluded: "E-cigarettes are a relatively new product and the long-term health effects are unknown. Now is the time for politicians and regulators to act - with public health campaigns to increase awareness and legislation to halt uptake in young people."

Heart doctors and researchers recommend:

Regulate advertising of e-cigarettes the same as tobacco to protect young people.

Age verification procedures to prevent adolescents from accessing e-cigarette websites.

Schools to educate children about the negative effects of e-cigarettes.

Public campaigns to raise awareness of adverse effects and prevent initiation of vaping.

Consider for smoking cessation only if conventional methods have failed and individuals are monitored for adverse effects.

Avoid e-cigarettes during pregnancy.

It is a fact that has long baffled doctors: Cancer in the small intestine is quite rare, whereas colorectal cancer, a neighboring though much smaller organ, is one of the leading causes of cancer death for men and women. What is it about the colon that seems to "attract" cancer?

To answer this question, Professor Yinon Ben-Neriah at Hebrew University of Jerusalem (HU)'s Lautenberg Center for Immunology and Cancer Research and his team led by Dr. Eliran Kadosh, found that cancer mutations are not necessarily bad actors, in and of themselves. In fact, in certain micro-environments like the gut, these mutations can actually help the body to fight cancer, not spread it. However, if the gut microbiome produces high levels of metabolites, like those found in certain bacteria and antioxidant rich foods like black tea and hot cocoa, then it acts as a particularly hospitable environment to mutated genes and will accelerate the growth of bowel cancers. Their breakthrough findings were published today in Nature magazine.

Ben-Neriah and his team kept gut microbiomes in mind as they took a closer look at gastrointestinal cancers, and may have found the reason why only 2% of cancers take root in the small intestine, whereas a whopping 98% of cancers take place in the colon. One major difference between these two organs is their levels of gut bacteria: small intestines contain few, whereas colons contain multitudes. "Scientists are beginning to pay more and more attention to the role gut microbiomes play in our health: both their positive effects and, in this case, their sometimes pernicious role in aiding and abetting disease," explained Ben-Neriah.

A little background. TP53 is a gene found in every cell. It produces a protein called p53 which acts as the cell's barrier, suppressing genetic mutations in the cell. However, when p53 becomes damaged, it no longer protects the cell. Quite the opposite, it drives the cancer, helping tumors spread and grow.

To test their theory that gut flora was at play, the researchers introduced mutated p53 ("cancer-driving") proteins into the gut. Amazingly, the small intestine reacted by converting the mutated p53 cancer driver back to normal p53, turning into "super-suppressors" that were better at suppressing cancer growth than healthy p53 proteins. However, when mutated p53 was introduced into the colon, they did no switcheroo but stayed true to their driving-cancer nature and promoted the cancerous spread. "We were riveted by what we saw," recalls Ben-Neriah. "The gut bacteria had a Jekyll and Hyde effect on the mutated p53 proteins. In the small bowel they totally switched course and attacked the cancerous cells, whereas in the colon they promoted the cancerous growth."

To further test their theory that gut flora was a major factor as to why mutated p53 were acting as tumor blockers in the small bowel but tumor accelerants in the colon, the scientists administered antibiotics to kill off the colon's gut flora. Once they did, the mutated p53 was not able to go on its cancer spree.

What's in this flora that makes colon cancer spread so quickly? A close analysis identified the culprit: gut flora that produces metabolites, aka "antioxidants", which are found in high concentrations in foods such as black tea, hot chocolate, nuts and berries. Tellingly, when the scientists fed mice an antioxidant-rich diet, their gut flora accelerated p53's cancer-driver mode. This finding is of particular concern to those patients with a family history of colorectal cancer.

"Scientifically speaking, this is new territory. We were astonished to see the extent to which microbiomes affect cancer mutations--in some cases, entirely changing their nature," shared Ben-Neriah. Looking towards the future, those at high-risk of colorectal cancer may want to screen their gut-flora more frequently and think twice about the foods they digest, antioxidant and otherwise.

A key component of ambient direct air capture (DAC) systems that remove carbon dioxide from the air is the sorbent material that is used to first capture the carbon and then to release it. Certain sorbent materials can pull carbon dioxide from the air as it flows over the material. It then releases the carbon when water is applied. As the material dries again, it absorbs carbon, and so on.

This elegant function of specific materials has been observed for several years by those working on DAC systems, like Klaus Lackner, an Arizona State University professor in the School of Sustainable Engineering and the Built Environment. Lackner has developed a system called "MechanicalTree" that uses sorbent materials to remove carbon from air.

Now, in a new paper in the early, on-line edition of Joule, Lackner and his colleagues lay out exactly how some of these sorbent materials capture and release carbon, a finding that could lead to the smarter design of sorbent materials at the heart of all carbon removal systems.

"We developed a better understanding of the moisture swing mechanism of these sorbents by demonstrating it in various materials and by developing computational tools and models that explain the concept," Lackner said. "We now understand the effect that drives the moisture swing, and this insight increases the range of materials that can do that."

The paper describes in detail and on a microscopic scale what is happening with the sorbent material when it is dry, it binds to carbon in the air, and when it is wet, it desorbs the carbon. The system was examined with quantum mechanics simulations and verified in experiments.

"This concept is not surprising to me because I've been playing with this stuff for a decade, but the moisture swing concept is still very novel and very different from other ways of loading and unloading a sorbent," Lackner explained. "We discovered this phenomenon 14 years ago, and for a long time it was a mystery on how it worked. Now it seems pretty obvious."

Overall, Lackner added, "this advance opens the door for more candidate materials and rational design. Many of those materials are far cheaper than what is often used as sorbents."

Co-authors on the paper "Moisture driven CO2 sorbents" are Xiaoyang Shi, Hang Xiao and Xi Chen, of Columbia University in New York City; and Kohei Kanamori and Akio Yonezu, of Chuo University in Tokyo. In addition to being a professor at ASU, Lackner is the director of the Center for Negative Carbon Emissions.

Lackner, a pioneer in the field of negative carbon emissions, has developed a
device, called the "MechanicalTree" that acts like a tree but is thousands of times more efficient at removing CO2 from ambient air. The "MechanicalTree," which is being commercialized by Silicon Kingdom Holdings, Dublin, Ireland, allows the captured gas to be sequestered or sold for re-use in a variety of applications, such as synthetic fuels, enhanced oil recovery or in food, beverage and agriculture industries.

Sorbent materials to capture the carbon are at the heart of Lackner's device.

Unlike other carbon capture technologies, SKH's technology can remove CO2 from the atmosphere without the need to draw air through the system mechanically using energy intensive devices. Instead, the technology uses the wind to blow air through the system. This makes it a passive, relatively low-cost and scalable solution that is commercially viable. If deployed at scale, the technology could lead to significant reductions in the levels of CO2 in Earth's atmosphere, helping to combat global warming.

Carbon dioxide is an odorless, colorless gas that is a byproduct of burning fossil fuels and other natural processes. Humans release more than 36 billion metric tons of CO¬2 into the atmosphere annually, significantly changing Earth's natural carbon cycle. The excess carbon traps heat and causes global warming.

The "MechanicalTree" is a novel geometry which is agnostic to wind direction and can work with the right sorbent for each location. Each "Tree" contains a stack of sorbent-filled disks. When the tree-like column is fully extended and the disks spread apart, air flow makes contact with the disk surfaces and the CO2 gets bound up. For regeneration, the disks are lowered inside the bottom container. Inside this chamber, the CO2 is released from the sorbent. The released gas is then collected, purified, processed and put to other uses, while the disks are redeployed to capture more CO2.

Many people have understood that our immune systems get weaker as we age, which in part explains why older people often get less protection than younger ones from annual influenza vaccines.

Now a team of scientists led by experts at Cincinnati Children's have taken a deeper look at how the immune system changes with age--and what they've found could make often-mediocre flu vaccines much more protective.

Their study, published online July 29, 2020, in the journal Science Advances, reports that rather than being weaker, the immune system in the elderly is actively suppressed and that this suppression is reversible. Their data show that triggering a strong response to vaccination in the elderly depends on relieving this suppression, which is driven by a key group of cells within our immune system. The co-authors call them "Tfh 10" cells, which stands for Interleukin 10-producing T follicular helper cells.

"These Tfh10 cells accumulate dramatically in our bodies as we age, and they have the effect of making older individuals less responsive to invading pathogens and less responsive to vaccines," says corresponding author David Hildeman, PhD, Interim Director, Division of Immunobiology.

The good news: it appears possible to boost vaccine power by managing Tfh 10 cells in a way that avoids harming the useful roles the cells play in fending off other types of disease.

If successful in the years to come, their approach may increase vaccine efficacy in the elderly, potentially reducing deaths caused by yearly influenza outbreaks, which have claimed 12,000 to 61,000 American lives per year since 2010, according to the Centers for Disease Control and Prevention.

"The age-related variation in response to vaccines is a huge issue," Hildeman says. "The current influenza vaccine is roughly 90% protective in young people, but only about 30% effective in the elderly."

Could this discovery apply to future COVID vaccines?

"Yes, it could. As the elderly do not respond well to multiple vaccines, it is highly likely that the elderly will also not respond as well as the young to new vaccines, either for COVID19 or other emerging pathogens," Hildeman says.

While some might be surprised to see a discovery that could help seniors coming from a pediatric medical center, many lines of research have no real age boundaries.

"Aging starts at birth," Hildeman says. "Often the lessons we learn about the decline of the immune system in later years can teach us about how the immune system begins in the young. The more we learn about defective immune responses in general, and strategies to overcome them, the more we can help kids with primary immunodeficiencies, and other immunologic diseases."

A non-stop quest for balance

Scientists at Cincinnati Children's have been studying the intricate details of the immune system for decades. Since the 1950s and the introduction of the Sabin oral polio vaccine, the medical center has been a leader in vaccine research--including working every year to help update influenza vaccine formulas and most recently recruiting thousands of people to test hopeful vaccines against COVID-19.

The new paper was co-authored by 20 experts at Cincinnati Children's and the University of Cincinnati plus colleagues in Germany, Alabama, and Indiana. It details a number of forces that act against each other as our immune systems respond over and over to infections. The study also describes how the balance of these elements changes as we age, with certain types of cells building up over the years to become more like harmful clutter instead of useful weapons.

In this study, the co-authors describe Interleukin-6 (IL-6) as a force that contributes to a persistent low-grade state of immune activation called "inflammaging." This state gets worse with age and appears to make people more likely to become frail, develop Alzheimer's disease, or suffer the fatal effects of cardiovascular disease.

Meanwhile, the body fights high levels of IL-6 by producing IL-10, known for its anti-inflammatory properties. Over the years, repeated cycles of response and counter-response result in an interleukin arms race that often leaves older bodies with excess levels of both IL-6 and IL-10.

One of the breakthroughs laid out in the new paper was pinpointing exactly where undesirable levels of IL-10 come from. The team conducted dozens of different experiments to chase down false leads and rule out competing ideas, using several of the highest tech methods available today.

"These findings are the result of five years of work stemming from a long-standing collaboration between my lab and Dr. Claire Chougnet's lab, contributions from several faculty-level scientists, and particularly the hard work of one amazing former graduate student, Dr. Maha Almanan," Hildeman says.

The detectives ultimately traced excess IL-10 production to the cell type they dubbed Tfh 10. Then, in mouse models, they showed that simple blockade of IL-10 at the time of vaccination could restore the antibody response nearly to the level of young animals.

"Our data suggest that, instead of enhancing proinflammation, transient blockade of IL-10 could be a novel strategy to enhance vaccine responses in the elderly and, due to its transient nature, is unlikely to have untoward effects on autoimmunity, cardiovascular disease, or frailty," the co-authors state.

What's next?

While the new paper reflects a combination of advanced computational and experimental lab work, much of which was confirmed in experiments involving mouse models and human cells, more studies are needed to demonstrate that Tfh 10 cells can be safely managed in people. Then more research will be needed to see how much of a boost to vaccine power can be achieved.

"We are currently in the process of testing whether IL-10 blockade will restore vaccine responses in larger mammals," Hildeman says. "If that proves effective, that would open the door to clinical trials."

Cincinnati Children's and the co-authors have filed a patent application for their discovery. Someday, if future projects succeed, the co-authors envision seniors receiving one shot that would temporarily prevent IL-10 from interfering with the body's response to a vaccine, but not permanently diminish IL-10 levels, and then the vaccine.

"If we can achieve that, the potential impact on lives could be felt worldwide," Hildeman says.

Modern applications as high resolution microsopy or micro- or nanoscale material processing require customized laser beams that do not change during propagation. This represents an immense challenge since light typically broadens during propagation, a phenomenon known as diffraction. So-called propagation-invariant or non-diffracting light fields therefore do not seem possible at first glance. If it were possible to produce them, they would enable new applications such as light disk microscopy or laser-based cutting, milling or drilling with high aspect ratios.

An international research team from the Universities of Birmingham (UK), Marseille (France) and Münster (Germany) has now succeeded for the first time to create arbitrary nondiffracting beams. "We implement an approach inspired by nature, in which any desired intensity structure can be specified by its boundaries," explains one of the authors of the study, Prof. Cornelia Denz from the Institute of Applied Physics at the University of Münster. The authors cleverly exploit light structures that can be seen in rainbows or when light is transmitted through drinking glasses: spectacular ray structures named caustics. They are bright focus lines that overlap, and thereby building networks that can be exploited for nondiffracting propagation. The team developed a method to use these caustics as a basis for the generation of arbitrary structures, and has thus created an intelligent manipulation of ray propagation. In this way, countless new types of laser beams can be formed on the micrometer scale, opening up completely new perspectives in optical materials processing, multidimensional signal transmission or advanced high resolution imaging.

Only some years ago it was possible to realize a few light fields that exhibit these non-diffracting properties, even though the theoretical idea is older: Concentric ring structures like the Bessel beam could be produced in a propagation-invariant way. The theory predicts a whole class of beams whose transverse shape is generated on elliptical or parabolic trajectories and represent natural solutions of the wave equation. Although there has long been a need for such customized light beams with these properties, they have hardly been produced experimentally because the invariance of the transverse intensity structure must be maintained during propagation.

When couples argue, mediation by a third party improves the outcome of the confrontation. But that's not all: mediation is also linked to heightened activity in key regions of the brain belonging to the reward circuit - this is the main conclusion of a study carried out by scientists from the University of Geneva (UNIGE) and published in the journal Cortex. The experiment consisted of giving couples behavioural questionnaires and subjecting them to functional magnetic resonance imaging (fMRI) prior to and following a session in which the two partners argue. Couples who received active mediation reported higher satisfaction than non-mediated couples at the end of the conflict. Heightened activation in the nucleus accumbens, a key region in the reward circuit, was also identified in the mediation group compared to the control group. This is the first time that a controlled, randomised study has succeeded in demonstrating the advantages of mediation for couple conflicts and identifying a related biological signature.

"We know from numerous studies that thinking about romantic love and your romantic partner activates the so-called reward circuit in the brain, which is associated with feelings of pleasure and motivation," begins Olga Klimecki, a researcher at the Swiss Center for Affective Sciences (CISA) and in UNIGE's Faculty of Psychology and Educational Sciences. "Until now, however, we didn't know the impact that couple conflict, and mediation by a third party, could have on this activation. It was precisely to fill this gap that we devised our study."

To conduct their experiment, the researchers enrolled 36 heterosexual couples (for statistical reasons and for comparison with previous studies) who were monogamous (according to the statements made by the couples themselves) and who had been together for at least a year. Before coming to UNIGE, participants had to check off a list of 15 standard subjects (in-laws, sexuality, finances, household chores, time spent together, etc.) which most often fuelled conflict with their partner.

Sources of conflict

"We then invited participants to start a discussion about one of these subjects," explains Halima Rafi, a doctoral student in the Faculty of Psychology and Educational Sciences, and the article's first author. "Some of the couples chose a box ticked by both partners. Others preferred to start on a subject that only one of the partners considered a source of conflict. This worked just as well, if not better. The first ten minutes were a generally little embarrassing, but things then began to flow with an impressive naturalness, and inevitably ended in conflict."

The session, which lasted one hour, was accompanied by a professional mediator who mediated the dispute in half of the cases. In the other half, the mediator remained entirely passive. Participants completed a behavioural questionnaire before and after their argument to measure their emotional state. In each couple one member's brain activity was measured before and after the dispute while they were shown images of their romantic partner or images of an unknown person.

General deactivation

Data from the questionnaires indicated that couples who benefited from active mediation were better at resolving conflicts, were more satisfied with the content and progress of the discussion, and had fewer residual disagreements.

"As for the neuroimaging results," continues Rafi, "the activations before the conflict replicated earlier studies on romantic love, showing an activation pattern in brain regions such as the striatum and orbitofrontal cortex. After the dispute, we quite logically observed a general deactivation in both groups in the regions associated with romantic love, including the striatum."

By contrast, when comparing couples who received active mediation with those who did not, the researchers found that the former tended to have greater activation in the nucleus accumbens after the conflict, which is a key region in the brain's reward circuit. Moreover, the participants who felt the most satisfied after the resolution of the conflict also had the highest nucleus accumbens activation when looking at their romantic partner compared to an unknown person.

"Our results suggest, for the first time, that third-party mediation has a significant and positive impact on the way couples argue, both behaviourally and neurally," concludes Klimecki. "This biological signature for romantic love is very interesting because it cannot be manipulated in the same way that an answer to a questionnaire could be. We would now like to continue the research and see, for example, whether we can measure similar effects in conflicts of a different type and not necessarily concerning love."

A new study from Australian scientists at the forefront of climate and health modelling suggests electric fans and water dousing could be a viable stay-at-home cooling strategy as the United States (US) anticipates extreme heat.

The risk of two major public health threats converging-- a heatwave and the COVID-19 pandemic--is quickly becoming a reality as the US approaches its hottest month of the year with COVID-19 cases continuing to rise.

"Authorities have acknowledged that the usual strategies recommended to protect individuals from heat-related illness such as seeking refuge in air-conditioned places including dedicated cooling centers or shopping malls risks further transmission of the virus," said senior author Associate Professor Ollie Jay from the University of Sydney (Australia).

"We also know that many of those who are most at-risk of COVID-19 are those also at-risk of heat-related illness, such as the elderly and those with cardiovascular or respiratory conditions."

"There is an urgent need for low-cost, accessible cooling strategies to protect the most vulnerable from heat-related illness and the spread of SARS-COV-2. Our study challenges outdated public health advice suggesting that fans are not beneficial in extreme heat."

In the new study, published in Science of the Total Environment, researchers from the University of Sydney's Faculty of Medicine and Health and Charles Perkins Centre examine if electric fans combined with spraying water directly onto the skin (self-dousing) is an effective stay-at-home cooling solution during summer conditions in the US

Key findings:

With modelling based on clinical trials and historic weather data the researchers found;

In 80 of the 105 metropolises examined electric fan-use would have resulted in effective cooling on every summer day over the last 20 years.

In only 3 of the 105 metropolises assessed (Phoenix and Tucson, Arizona and Las Vegas, Nevada), this method would not have been effective more than five percent of the time.

This means 65 percent of the US population (200 million of the 222 million residents living in these most populous metropolises) could have effectively used this strategy to keep cool on 100 percent of summer days.

They conclude that this solution could be potentially recommended by health authorities as a safe and effective stay-at-home cooling strategy across vast swathes of the Northeast, Southeast and Midwest regions of the United States, as well as the West Coast.

The researchers acknowledge that while the modelling is conservative (based on the physiology of an older adult) it can only show when fans would or would not be effective based on climate. As with many public health interventions, an individuals' response to the cooling strategy may be influenced by their health status.

The modelling explained:

Based on previous work published in JAMA and Annals of Internal Medicine the authors modelled the humidity-dependent threshold temperature under which fans and self-dousing provide a beneficial cooling effect.

The previous trials conducted on participants in a climate-controlled chamber show that that in hot, humid conditions fans lower core body temperature and cardiovascular strain and improve thermal comfort. However, fans can be detrimental in very hot, dry conditions.

These data were analysed alongside historic weather data (temperature and associated relative humidity) recorded at any point over the last 20 years (2000 to 2019 inclusive) for 105 of the most populated metropolis areas in the United States.

First author and PhD student Lily Hospers said: "Importantly, this research proposes a potential cooling strategy that can be used at home during the current pandemic, therefore circumventing the need for potentially risky excursions into public spaces and expensive home-based air-conditioning."

Declaration: The authors declare no competing interests.