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Annapolis, MD; September 24, 2019--In 1999, West Nile virus was detected in the United States for the first time, and within five years it had spread from New York across the contiguous United States and into Canada, Mexico, and Central and South America. Transmitted to humans by mosquitoes that feed on infected birds, West Nile virus has served as a wake-up call to the challenge of preventing the spread of mosquito-borne diseases in the era of globalized trade and travel.

Twenty years later, West Nile virus remains firmly established in the Americas, and other mosquito-borne diseases such as chikungunya, Zika, dengue, and strains of St. Louis and Eastern equine encephalitis have made incursions or reappearances as well. As the outbreak has continued, researchers have scrutinized West Nile virus and the mosquitoes that carry it. Though eradication of West Nile virus in the Americas remains yet beyond our capability, the body of knowledge built since 1999 is now empowering efforts to minimize its impact and better prevent and respond to other mosquito-borne diseases.

To take stock of these lessons learned, the Journal of Medical Entomology has published a special collection of articles today from an array of experts in public health, veterinary medicine, entomology, ecology, and mosquito management, synthesizing their ideas gleaned from research conducted and progress made over the past 20 years.

Below, several experts whose perspectives appear in the collection offer their take on a central question: "What's the biggest lesson we've learned from 20 years of research on West Nile virus?"

Lyle R. Petersen, M.D., Division of Vector-Borne Diseases, National Center for Emerging and Zoonotic Infectious Diseases, U.S. Centers for Disease Control and Prevention:

"To expect the unexpected. Before the introduction of West Nile virus to the US in 1999, we never expected that an exotic arbovirus would be imported to a major metropolitan area, become endemic in all 48 contiguous states, cause outbreaks of unprecedented size nearly every year, and threaten the U.S. blood supply. The societal costs have been enormous."

Angela M. Bosco-Lauth, Ph.D., Department of Biomedical Sciences, Colorado State University:

"West Nile virus has demonstrated the need for a truly 'one health' response to pathogen emergence. It is so vitally important that science and research is open and collaborative in nature and that human health, veterinary health, and environmental health do not exist as silos but rather work together toward a common goal."

Ilia Rochlin, Ph.D., Center for Vector Biology, Rutgers University:

"West Nile virus is very adaptable. Its transmission cycle can be maintained by different Culex mosquito species and avian hosts. The virus can thrive under an amazing diversity of environmental conditions, from dry prairies to humid broadleaf forests and from the rural agricultural Southwest to the upscale suburban Northeast. Few other arboviruses display similar ecological plasticity."

A. Marm Kilpatrick, Ph.D., Department of Ecology and Evolutionary Biology, University of California, Santa Cruz:

"Disease invasions can have lasting effects on both human and wildlife health. The initial invasion often inspires fear and reactions that, in hindsight, are exaggerated. However, the lasting impacts are often unanticipated, and the combination of climate variability and the evolution of the pathogen, hosts, and vectors can lead to re-emergence long after the initial invasion."

William K. Reisen, Ph.D., Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California, Davis:

"Effective overwintering is critical for virus persistence and necessary for effective amplification to outbreak levels the following spring. However, despite detailed research on the invasive West Nile virus as well as related encephalitis strains, it still is not clear how these viruses spend the winter at temperate latitudes when temperatures are too cold for virus replication and vector mosquito blood-feeding activity. Multiple mechanisms have been explored, but definitive answers remain evasive."

Roger S. Nasci, Ph.D., Vector-Borne Disease Consulting LLC:

"Though there is good evidence that intensive mosquito-control efforts can stop virus transmission and prevent human cases once a West Nile virus outbreak has started, preventing outbreaks from occurring in the first place remains a major challenge. However, examples of early-season mosquito control effectively reducing West Nile virus amplification and expansion indicate that outbreak prevention is feasible if sufficient information about the local West Nile virus transmission ecology and adequate mosquito-control resources are available."

Cells that become senescent irrevocably stop dividing under stress, spewing out a mix of inflammatory proteins that lead to chronic inflammation as more and more of the cells accumulate over time. Publishing in the September 24 edition of Cell Reports, researchers at the Buck Institute identified 44 specific senescence-associated proteins that are involved in blood clotting, marking the first time that cellular senescence has been associated with age-related blood clots.

"The incidence of venous thrombosis, which includes deep vein thrombosis and pulmonary embolism is extremely low until the age of 45, when it begins to rise rapidly. Over time it becomes a major risk factor for death. By 80, the condition affects five to six people per thousand individuals," said Judith Campisi, PhD, Buck professor and senior co-author of the study. "Blood clots are also a serious side effect of chemotherapy, which sets off a cascade of senescence in those undergoing treatment. That's why blood thinners, which carry their own risks, are often included in treatment protocols."

Scientists in the Campisi lab and other labs around the world are working to develop senolytics, drugs which would clear senescent cells from the body, potentially providing treatment options for many age-related diseases that are either caused or linked to senescence. They include Alzheimer's and Parkinson's diseases, cardiovascular disease, osteoarthritis, macular degeneration, age-related cancers and sarcopenia, among others.

In this study, researchers validated the expression of some of the specific factors in cultured cells and in mice, which were treated with doxorubicin, a widely-used chemotherapy drug which induces widespread senescence. Those mice showed increased blood clotting, similar to what happens in humans who undergo chemotherapy. "Conversely, when we selectively removed senescent cells in specially bred transgenic mice, the increased clotting caused by doxorubicin went away," said Christopher Wiley, PhD, assistant research professor and lead author of the paper.

The way the research came together highlights the strength of the Buck's collaborative environment says Buck professor and co-senior author Pankaj Kapahi, PhD. "We knew we had to delve into the complexity of the SASP - the senescence-associated secretory phenotype - in order understand its biological function. We brought the Schilling lab and its expertise in mass spectrometry into the mix which enabled a new understanding of how specific aspects of the SASP might be targeted. Our hope is that this research will move the field forward by improving our understanding of the implications of the SASP."

Campisi says the work is also an endorsement of big data bioinformatics, which was used to analyze results generated in the Schilling lab. Researchers identified 343 proteins secreted by senescent human fibroblasts, with 44 linked to clotting. "Some people throw up their hands and say senescence is too complicated to make sense of research results," Campisi said. "But this paper shows that we can identify what's going on. That information will likely be useful in targeting who gets treatment and when they should get it." Several labs at the Buck are involved in a federally-funded project to develop biomarkers for cellular senescence.

BOSTON (Sept. 24, 2019, 11:00 a.m. ET)--Despite years of steady advice and guidance on healthy eating, a 'report card' on the American diet shows adults are still consuming too many low-quality carbohydrates and more saturated fat than recommended, according to researchers at the Friedman School of Nutrition Science and Policy at Tufts University and the Harvard T.H. Chan School of Public Health. The study, published today in JAMA, looked at dietary trends over an 18-year period.

Although the study identified some dietary improvements, it also found that low-quality carbohydrates from refined grains, starchy vegetables, and added sugars accounted for 42 percent of the typical American's daily calories. High-quality carbs, from whole grains and whole fruits, accounted for only 9 percent. Over the study period:

Total carbohydrate intake went down 2 percent, and Americans were successful in cutting back on low-quality carbs by 3 percent. However, consumption of healthier, high-quality carbs increased by only 1 percent.

Total fat intake increased by 1 percent, half of which was saturated fat. Total saturated fat intake represented 12 percent of daily calories, which is above the recommended daily amount of 10 percent.

The study authors note that any dietary improvements were less pronounced for older people and those of lower income or educational attainment:

Higher income adults reduced their intake of low-quality carbs by 4 percent over the study period, but those living below the poverty line cut their intake by only 2 percent.

While most Americans improved adherence to dietary guidelines, there was no improvement seen for adults over 50 years old, people with less than a high school education, and those living below the poverty line.

"Although there are some encouraging signs that the American diet improved slightly over time, we are still a long way from getting an 'A' on this report card. Our study tells us where we need to improve for the future," said co-senior author Fang Fang Zhang, nutrition epidemiologist at the Friedman School of Nutrition Science and Policy at Tufts University. "These findings also highlight the need for interventions to reduce socioeconomic differences in diet quality, so that all Americans can experience the health benefits of an improved diet."

The study drilled down into consumption trends of specific nutrients, such as plant-based protein and saturated fatty acids, which the researchers said provide insights on how changes in food sources might offer health benefits.

"For example, most of the proteins that Americans consumed were from meats--including red and processed meat. Proteins consumed from seafood and healthy plant sources, such as whole grains, nuts, and legumes, remained a much smaller proportion," said co-senior author Shilpa Bhupathiraju, research scientist at the Harvard T.H. Chan School of Public Health, also with Harvard Medical School and Brigham and Women's Hospital. "Our research suggests that Americans have an opportunity to diversify their sources of protein to include more seafood, beans, soy products, nuts and seeds."

"Because low-quality carbs are associated with disease risk, taking in higher-quality carbs could mean better health for Americans in the future," said first author on the study, Zhilei Shan, nutritional epidemiology fellow at the Harvard T.H. Chan School of Public Health. At the time of this study, he was also working under the auspices of Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.

The study examined the diets of 43,996 adults using data from the National Health and Nutrition Examination Survey (NHANES). Participants are representative of the national adult population and completed at least one valid 24-hour dietary recall from nine consecutive cycles of the NHANES (1999 to 2016). Researchers used the USDA's Food and Nutrition Database for Dietary Studies (FNDDS) to estimate nutrient intake. To assess overall diet quality, the researchers used the Healthy Eating Index (HEI)-2015, which measures adherence to the 2015-2020 Dietary Guidelines for Americans.

Limitations of the study include the fact that self-reported food recall data is subject to measurement error due to daily variations in food intake, but steps were taken to improve estimates.

WASHINGTON, D.C., September 24, 2019 -- Being able to accurately forecast how much solar energy reaches the surface of the Earth is key to guiding decisions for running solar power plants.

While day-ahead forecasts have become more accurate in recent years, the solar community lacks a unified verification procedure, and assessing how one forecast compares to another is difficult. New work in the Journal of Renewable and Sustainable Energy, from AIP Publishing, looks to provide a standard of reference to the field.

Researcher Dazhi Yang proposed an improved way to assess day-ahead solar forecasting. The proposed method combines two popular reference methods for weather forecasting, namely persistence and climatology. Using a weighted linear combination of both methods, his approach provides a new way to gauge the skill of a forecaster.

"There is a large collection of solar forecasting works in the literature. However, all papers claim superiority, which is clearly not possible," Yang said. "Without a standardized reference method to gauge forecast accuracy, we cannot compare methods reported in different papers, using different data from different locations and timescales."

Persistence reference methods assume weather does not change from day to day, and tomorrow's forecast can be drawn from today's observations. Climatology examines the long-term averaged observations over time to generate a forecast.

"It's generally unclear which type of forecast is more accurate, making it difficult to determine the best forecasters," Yang said. "A standard of reference is much needed in the community, so that forecasters can calculate the skill score and thus perform a direct, 'apples-to-apples' comparison."

To demonstrate the universality of the proposed method, Yang applied the framework to a dataset from the Baseline Surface Radiation Network. The network's 66 stations can be found on all seven continents and on an island in every ocean, and has been operating for 27 years.

For some applications, Yang's combined approach proved to be more optimal than either climatology or persistence alone.

If the goal is to assess the reliability of a forecast, he found his combined reference is optimal. If the goal is to maximize how much a forecast was able to differentiate between different forecasting situations, then forecasters should use a form of the persistence approach that considers the hourly changes of the weather.

Such conditional findings might provide an answer for why there isn't a consensus in the first place, he said. Yang hopes that, with the help of journal editors, who might bolster the profile of the new reference method, this framework will become the standard of reference for day-ahead solar forecasting.

WASHINGTON, D.C., September 24, 2019 -- By studying the brain dynamics of 28 subjects with epilepsy, scientists demonstrated there is no evidence for a previously suspected warning sign for seizures known as "critical slowing down."

In 2013, some of the first seizure-prediction devices were developed and successfully tested. Although extensive research efforts have successfully identified predictors of imminent seizures, the concept of critical slowing down as an index for seizure susceptibility has been controversial and remained unproven.

Critical slowing down refers to characteristic changes in the behavior of a complex system that approaches a theoretical tipping point. When this point is exceeded, it can lead to impactful and devastating changes. An epileptic human brain is considered an excellent example of a system such as this, due to the extreme and distressing nature of a seizure.

In a paper published in Chaos, from AIP Publishing, researchers investigated recordings of brain dynamics that captured 105 epileptic seizures using time-resolved estimates of early warning indicators of the seizures.

"In our investigations, we used the most prominent indicators and showed that critical slowing down prior to human epileptic seizures is not verifiable," neurophysicist Thorsten Rings said. "This demonstrates that the concept underlying critical slowing down is too simple of a model for the human brain."

Instead of critically slowing down, the researchers discovered the seizures acted oppositely and critically sped up, indicating the brain dynamics were less sensitive to changes and experienced a faster return to an unperturbed state.

"Similar indicators of critical slowing down can even be observed in relation to daily rhythms, such as sleeping and waking, but we lack clear-cut evidence for critical slowing down preceding such changes," researcher Theresa Wilkat said. "Therefore, it is hard to clearly distinguish between a critical transition into a seizure and a critical transition into other states."

An in-depth model of the transition into a seizure is still missing, but considering their research, Klaus Lehnertz and his team said the concept of critical slowing down is insufficient as a predictive method. They believe future studies should develop improved models and analysis techniques.

"A promising future approach might be to investigate how seizures emerge from large-scale brain networks by taking into account their time-varying structure and function," Lehnertz said.

According to a new study carried out at the University of Eastern Finland, the distribution of drug molecules within the brain can be improved by utilizing LAT1, which is expressed highly in the brain. By converting drug molecules temporarily into prodrugs, derivatives that can utilize LAT1 for cell entry and subsequently release the active parent drug within the target cells. This way one can achieve many times higher concentrations compared to the treatment with the parent drugs alone, which cannot utilize LAT1. This is very important, particularly in a situation where the final target protein is located inside the cells. This study was published in Scientific Reports in the beginning of September.

The blood-brain barrier (BBB) regulates the delivery of all substances from the blood circulation into the brain. Its main function is to protect the central nervous system (CNS) from harmful substances while allowing the entrance of required nutrients, such as sugar, water and oxygen. Therefore, the majority of drug compounds, which are supposed to act within the brain, do not permeate across the BBB at sufficiently high levels in order to treat brain diseases effectively. However, the BBB expresses several transporters by which the essential nutrients are delivered from the blood circulation into the brain.

The research group led by Adjunct Professor Kristiina Huttunen from the University of Eastern Finland, School of Pharmacy, has been studying LAT1 for a good period of time. They have also proved that LAT1 can be efficiently utilized for brain-targeting and enabling the delivery of drugs across the BBB, since LAT1 is expressed highly in the brain in comparison to any other healthy organs. In the present study, the research group investigated the utilization of LAT1 in intrabrain-targeted drug delivery after the drug molecules have passed the BBB.

It was proved for the first time in this study that functional LAT1 is expressed on the cell surface of neurons, but also in the supporting cells, astrocytes and microglia. In addition, in this study it was demonstrated that the LAT1-utilizing prodrugs of several different compounds, such as anti-inflammatory drug, ketoprofen and antioxidant ferulic acid, displayed improved cellular uptake compared to their parent drugs. The same results were also achieved with astrocytes having features of Alzheimer's disease.

"We were also able to identify structural requirements for the prodrugs that could enable targeting between the different brain cell types in future, says the first author of the study, PhD student Johanna Huttunen.

Thus, by utilizing the LAT1-prodrug approach, it is possible to achieve drug concentrations relevant for the pharmacological effects in the diseased brain, which has been one of the major challenges to overcome in the CNS-drug development. Adjunct Professor Huttunen says that the best results, i.e. the development of more effective drugs to treat brain diseases, can be attained only if drug delivery within the brain is taken into account as early as possible in the drug development phase; this would be when we are structurally designing novel CNS-drugs.

Today's electronics industry is increasingly focusing on computers or smartphones with screens that can be folded or rolled. Smart clothing items make use of wearable micro-devices or sensors to monitor bodily functions, for example. However, all these devices need an energy source, which is usually a lithium-ion battery. Unfortunately, commercial batteries are typically heavy and rigid, making it fundamentally unsuitable for applications in flexible electronics or textiles.

A remedy for this problem is now being created by Markus Niederberger, Professor for Multifunctional Materials at ETH Zurich, and his team. The researchers have developed a prototype for a flexible thin-film battery that can be bent, stretched and even twisted without interrupting the supply of power.

What makes this new battery special is its electrolyte - that part of the battery through which lithium-ions move when the battery is charged or discharged. This electrolyte was discovered by ETH doctoral student Xi Chen, lead author of the study that recently appeared in the scientific journal Advanced Materials.

Systematically employing bendable components

Following the design of commercial batteries, this new type of battery is built in layers like a sandwich. However, it marks the first time that researchers have used flexible components to keep the whole battery bendable and stretchable. "To date, no one has employed exclusively flexible components as systematically as we have in creating a lithium-ion battery," Niederberger says.

The two current collectors for the anode and the cathode consist of bendable polymer composite that contains electrically conductive carbon and that also serves as the outer shell. On the interior surface of the composite, the researchers applied a thin layer of micronsized silver flakes. Due to the way the flakes overlap like roof tiles, they don't lose contact with one another when the elastomer is stretched. This guarantees the conductivity of the current collector even if it is subjected to extensive stretching. And in the event that the silver flakes do in fact lose contact with each other, the electrical current can still flow through the carbon-containing composite, albeit more weakly.

With the help of a mask, the researchers then sprayed anode and cathode powder onto a precisely defined area of the silver layer. The cathode is composed of lithium manganese oxide and the anode is a vanadium oxide.

Water-based gel electrolyte

In the final step, the scientists stacked the two current collectors with the applied electrodes on top of each other, separated by a barrier layer similar to a picture frame, while the gap in the frame was filled with the electrolyte gel.

Niederberger emphasises that this gel is environmentally more friendly than the commercial electrolytes: "Liquid electrolyte in today's batteries are flammable and toxic." In contrast, the gel electrolyte that his doctoral student Chen developed contains water with a high concentration of a lithium salt, which not only facilitates the flow of lithium ions between cathode and anode while the battery is charging or discharging, but also keeps the water from electrochemical decomposition.

The scientists joined the various parts of their prototype together with adhesive. "If we want to market the battery commercially, we'll have to find another process that will keep it sealed tight for a longer period of time," Niederberger says.

Numerous potential applications

More and more applications for a battery like this are emerging every day. Well-known manufacturers of mobile phones are vying with each other to produce devices with foldable screens. Other possibilities include rollable displays for computers, smartwatches and tablets, or functional textiles that contain bendable electronics - and all of these require a flexible power supply. "For instance, you could sew our battery right into the clothing," Niederberger says. What's important is, in the event of battery leakage, to ensure that the liquids that come out cause no damage. This is where the team's electrolyte offers a considerable advantage.

However, Niederberger stresses that more research is necessary to optimise the flexible battery before they consider commercialising it. Above all, the team has to increase the amount of electrode material it can hold. A new doctoral student has recently begun refining the stretchable power supply. The inventor of the initial prototype, Xi Chen, returned to his homeland of China after completing his doctoral thesis to take up a new job - as a consultant for the battery industry.

QUT researchers have come up with a new, safe way to clean up oil spills using compounds equally useful as common household cleaning products.

There have been more than 700 oil spills worldwide in the past 20 years, polluting oceans and coastlines as well as endangering marine ecology and other wildlife.

Associate Professor Jingsan Xu said the team from QUT's Science and Engineering Faculty, had invented a nontoxic, low-cost, easily processed foam for oil removal.

He said when an oil spill occurred, the foam could be sprayed onto its surface to absorb the waste very quickly. The same principal could be applied to spills in the home of cooking or other oils. The foam is then easily scraped away for safe disposal.

A paper revealing their findings - Reversible Switching of the Amphiphilicity of Organic-Inorganic Hybrids by Adsorption-Desorption Manipulation - has just been published in The Journal of Physical Chemistry.

"Thousands of tons of oil have been disgorged into our oceans over the decades. One of the most memorable was the Exxon Valdez oil spill in Prince William Sound, Alaska, in 1989 which spilled 37,000 metric tons of crude oil and is considered one of the worst ever human-caused environmental disasters," said Professor Xu.

"More recently, the Deepwater Horizon oil spill in the Gulf of Mexico in 2010 had the dubious honour of becoming the largest marine oil spill in the history of the petroleum industry.

"Although there are methods for cleaning up oil spills, they are usually very messy and difficult to contain while some methods, such as in situ burning, create more hazards for the environment.

"Sorbents - large sponges - are also used but only for the removal of final traces of oil or in places skimmers cannot get to. The key to saving the environment from maximum damage is to mop up the oil as quickly as possible.

"So what we have focussed on is the adaptability and possibilities associated with surfactants which are already widely used in research, industrial production and daily lives via household cleaning products.

"Surfactants are compounds that lower the surface tension between two liquids, between a gas and a liquid, or between a liquid and a solid - in other words, they can be detergents, wetting agents, emulsifiers, foaming agents, and dispersants.

"One way to remove the floating oil from sea surface is adsorption. Hydrophobic porous foam - low density material that can float on liquid - is a promising candidate to achieve that and we recently reported on the synthesis of a hydrophobic hybrid foam which showed excellent adsorption performance to a range of organic liquids."

Professor Xu and the team have now created what they call a 'hybrid surfactant' by combining an oil-soluble molecule, stearic acid, with water-dispersible alumina nanofibers via chemisorption at the oil?water interface.

"Our hybrid surfactant exhibits reversible switching between hydrophilic (molecules attracted to water) and lipophilic (able to dissolve in fats, oils, lipids, and non-polar solvents) states by manipulating the adsorption?desorption volume of stearic acid attached to the alumina nanofibers," he said.

"Therefore, the emulsions stabilised by this organic?inorganic hybrid can reversibly transform between oil-in-water and water-in-oil type by simple mechanical manipulation.

"Unlike conventional approaches, no other external stimulus is needed to set the amphiphilic properties of the hybrid surfactant. This protocol may have significant applications in cosmetic, food and other fields.

"As a bonus, organic?inorganic three-dimensional solid foams can be readily prepared based on the emulsion system, which demonstrates a strong potential for use in evaporating oil spills - in the ocean or the kitchen - in a very quick fashion."

A research group comprising Associate Professor Taku Hasobe and Assistant Professor Hayato Sakai of the Keio University Faculty of Science and Technology, Toshiyuki Saegusa of the Keio University Graduate School of Science and Technology (completed master's program in 2019), and Professor Yasuhiro Kobori and postdoctoral researcher Hiroki Nagashima of the Kobe University Molecular Photoscience Research Center found that when light was exposed to the surface of a tetracene alkanethiol-modified gold nanocluster, which they developed themselves, twice as many excitons could be converted compared to the number of photons absorbed by the tetracene molecules. They also found that these excitons have a lifetime that is approximately 10,000 times longer than that of the organic molecules on conventional gold surfaces. Furthermore, they succeeded in converting singlet oxygen (a type of reactive oxygen species) at a highly efficient conversion rate of 160%, far exceeding 100% conversion, in comparison to the number of absorbed photons. Singlet oxygen is used in photodynamic therapy (treatment of cancer with light) and organic synthesis, among other applications.

These findings are expected to contribute to areas such as solar energy conversion, electronics, life sciences, and medical care in the future. The outcomes of this research were published in the online version of the American scientific publication the "Journal of the American Chemical Society" on September 6.

1. Main points of research

Normally, when one photon is absorbed by a molecule, only one exciton (a bound state of an electron hole and an electron) is formed. However in recent years, singlet fission (which forms two excitons from the absorption process of a single photon) is gathering much attention worldwide, although significant work remains before it can be used in chemical reactions.

In general, an organic molecule that has been chemically modified and integrated into the surface of metals loses significant excitation energy when compared to the isolated state of an organic molecule.

In order to solve all of the above problems at once, a tetracene alkanethiol-modified gold nanocluster was newly designed and synthesized. An increase in lifetime of about 10,000 times was achieved by greatly suppressing the rapid loss of excitation energy on the metal surface. In addition, excitons were formed with high efficiency through singlet fission, and the efficiency of generating singlet oxygen was successfully improved to about 160% (fig. 1).

2. Content of research and results

A research group comprising researchers from Keio University, Kobe University, and Tampere University focused on a photoreaction called singlet fission. This is a process in which two molecules positioned nearby interact with each other after one of the molecules absorbs a photon, forming two excitons. With the goal of solving the abovementioned problems all at once, they considered modifying tetracene (whose chemical structure is composed of four benzene rings connected in a straight line) into a metal nanocluster by the self-assembled monolayers (SAMs) method (fig.2). SAMs are monolayers made by chemically modifying organic ligands such as alkanethiol on the metal surface, and have been an important core technology for recent advancements in nanotechnology. In singlet fission, where reactions take place between two molecules located close to each other, the distance and orientation between the two molecules must be strictly controlled. When the surface of a gold nanocluster is chemically modified using tetracene homodisulfide (fig.2, right) that is composed of two tetracene alkanethiol with the same alkyl chains of length n, the probability of tetracene with the same alkyl chains of length n being placed in close proximity inevitably increases. Therefore, as shown on the left side of figure 2, tetracene heterodisulfide (Tc-C11-S-S-Cn-Tc) with different alkyl chain lengths (for which one had a length of n = 11 while the other had a length of n = 5, 7, or 9), were newly synthesized, and the gold nanocluster surface was chemically modified. Using tetracene heterodisulfide and tetracene homodisulfide, a series of tetracene alkanethiol-modified gold nanoclusters was synthesized (a block [cluster] of gold with 144 gold atoms whose surface was chemically modified by 60 tetracenes with alkanethiol as the medium). As a result, it was possible to create bimolecule arrangements with the optimal distance and orientation for singlet fission to occur efficiently on the gold nanocluster surface (while suppressing reverse reactions).

Aggregation-induced emission (AIE) was first reported by Tang`s group in 2001. Many research efforts have been devoted to the exploration structure-property-application of AIE. The focal points and hot spots of AIE are to design new structural systems and to illuminate the relationship of structural properties. Many new compounds with AIE characteristics have been designed and synthesized to enrich the members in AIE family. However, there are almost no reports thus far on the analog 1,1,2,4-tetraphenyl-1,3-butadiene (TPB) that was studied in AIE fields.

Recently, Professor Yuping Dong's group, from Beijing Institute of Technology, demonstrated a new member of AIE family: TPB with conformational sensitivity. The experimental results show that TPB-1, TPB-2 and TPB-3 have typical AIE characteristics, that is, there is no fluorescence in the solution, and strong fluorescence in the aggregate state. Unlike the existing AIE molecules, the TPB derivative does not have a strong electron-withdrawing electron group. The emission wavelength of the aggregated state is nearly 80 nm larger than that of the molecular state. All the experimental results indicated that 4-position of arylene group had a sensitively changing conformation in different state, which resulted in the emission wavelength movement.

Conformational sensitivity was used to monitor the critical transition point of polyelectrolyte complexes of PSS/PADAMA in different KBr concentration. Inserting TPB-3 molecule into PSS/PADAMA system with a mass fraction of 0.15% detected the critical transition point of PSS/PADAMA polyelectrolyte complexes in about 1.8 mol/L of KBr.

Highlights

The dorsal anterior cingulate cortex (dACC) causes motor performance deterioration due to anxiety

Transcranial magnetic stimulation of the dACC reduces the performance deterioration

This method could potentially be used to help athletes and musicians overcome anxiety

Abstract

Researchers in the Center for Information and Neural Networks (CiNet), the National Institute of Information and Communications Technology (NICT, President: Hideyuki Tokuda, Ph.D.), Japan and the Centre national de la recherché scientifique (CNRS), France used fMRI to discover a new neural mechanism involving the dorsal anterior cingulate cortex (dACC) to explain how anxiety deteriorates physical performance. Moreover, the performance deterioration was rescued by suppressing brain activity with transcranial magnetic stimulation to the dACC. The findings would provide a new therapeutic strategy for athletes, musicians and other performers susceptible to anxiety during performance. The paper was published online in Nature Communications on September 19, 2019.

Background

Athletes, musicians and other performers, be they professionals or amateurs, are required to conduct rapid complex movements that can be affected by anxiety. Influential self-focus theory postulates that the motor skills required for these actions become automatic and unconscious during learning, but anxiety causes an interference between conscious and unconscious processing that can negatively impact the performance. However, no behavioral or brain data has confirmed the theory. Such data would provide therapeutic targets that negate the effects of anxiety on motor performances.

Achievements

Principle Investigator Masahiko Haruno (NICT), with Dr. Gowrishankar Ganesh (CNRS) and Dr. Takehiro Minamoto (Shimane University) conducted fMRI by designing a novel behavioral task and found a correlation between activity in the dACC and the motor performance deterioration due to anxiety. The application of TMS to suppress dACC activity rescued the deterioration, providing the first direct evidence that suppressing anxiety-stimulated regions could reduce performance deterioration.

In general, specific motor skills, such as those used in tennis or playing the piano, require repeated practice to memorize the motions and their order. In the new study, the researchers simulated this practice on a computerized 10-step rapid button press task. Part-learners learned the task in two parts, one 6 steps long and the other 4 steps long. Finally, they practiced all 10 steps at once. Single-learners, on the other hand, learned the 10-step rapid button presses together without breaking them into parts. After the learning, both groups of learners were asked to conduct the entire 10-step task and given an electrical shock if they made a mistake during the performance (Fig. 1A, anxiety test session).

Part-learners proved more adept at learning the task in the training sessions based on the speed and number of errors with which they completed the task. However, when the anxiety test session started, their performance dropped noticeably to a level worse than single-learners (Fig. 1B, J represents the junction of the two parts). This finding is consistent with the self-focus theory, which would expect performance to decline with anxiety.

fMRI revealed that the part-learners showed increased activity of the dACC at the time of the junction in the test session (Fig. 1C). Applying TMS to this region for 5 minutes (1 Hz) prior to the test session (Fig. 1D) eliminated the performance degradation in part-learners (Fig. 1E). On the other hand, part-learners who received sham TMS did not show improvement.

These experiments show for the first time the brain region responsible for performance degradation caused by anxiety and a possible therapeutic strategy using TMS.

Future research

In addition to more study of the dACC neural circuits that connect anxiety to performance degradation, the group will investigate how TMS can enhance the performance of athletes, musicians and other performers.

Modern electronics is based on doped semiconductors. To synthesize electronic components, dopant atoms such as aluminum or phosphorus are embedded into crystals of ultrapure silicon. This allows for tailoring semiconductor conductivity according to the desired application. In modern electronic computer processors, miniaturized to just a few nanometers, only less than ten dopant atoms are relevant for the functionality. Quantum components, which are used for novel quantum computers or quantum simulators, will go even one step further in that they require an array with only single dopant atoms in a high-purity crystal.

Physicists at Johannes Gutenberg University Mainz (JGU) led by Professor Ferdinand Schmidt-Kaler now have developed a method to implant precise numbers of individual dopant ions into a solid crystal. Their technique implants the rare earth element praseodymium into an yttrium-aluminum garnet crystal. These crystals were subsequently examined under a high-resolution confocal microscope in collaboration with a team of researchers headed by Professor Jörg Wrachtrup at the University of Stuttgart. They determined a positioning accuracy of 35 nanometers. In principle, this accuracy is already sufficient to implant arrays of dopant ions into components for future quantum processors.

The research results were published as a highlight in the current volume of the international journal Physical Review Letters and represent an important innovation with a wide potential for applications, as the method can be extended to other crystals and dopant atoms.

An ambitious new Mersey barrage concept shows how tidal energy projects can offer many benefits to society in addition to clean renewable energy.

When designed holistically, tidal barrage schemes can provide additional transport links for commuters, become tourism destinations, mitigate wildlife habitat loss, as well as provide opportunities to boost people's health and wellbeing with additional options for cycling and walking, say researchers from Lancaster University and the University of Liverpool.

The academics have proposed an ambitious new design for a mooted tidal energy barrage on the Mersey Estuary, which has one of the largest tidal ranges in the UK. Their concept, which is based on the shape of a whale and includes buildings and platforms for recreation in the centre of the river, illustrates the additional benefits tidal schemes can bring.

The researchers developed their Mersey estuary design to illustrate how developers can apply a novel decision-making framework for tidal schemes called the 'North West Hydro Resource Model'.

This model, which was developed by academics at Lancaster University's Engineering Department, includes a range of factors that should be considered for tidal scheme designs, including: energy generation; land use; habitat; flood risk; transport; fisheries; cultural heritage; water supply; tourism and job creation.

George Aggidis, Professor of Energy Engineering at Lancaster University, lead researcher on the paper and creator of the North West Hydro Resource Model, said: "We need to view tidal energy projects holistically and recognise that they provide opportunities beyond energy generation, including environmental, societal and economic opportunities.

"The UK is uniquely positioned to benefit from tidal power, but so far no schemes have managed to get off the drawing board. By considering the needs of people, and the need to create compensatory habitats for wildlife, organic architectural designs like ours show how developers can enhance, rather than detract, from estuaries like the Mersey.

"Tidal barrages and lagoons can offer significant advantages over other sources of renewable power - we need to keep these additional opportunities in mind when comparing the costs and benefits of different forms of energy generation," added Professor Aggidis.

The researchers say that with the right design a Mersey barrage has the potential to become a globally identifiable piece of architectural infrastructure - a 'hydropower landmark' boosting tourism to the region.

Their vision includes new transport and leisure links from Port Sunlight on the Wirral to the Festival Gardens on the Liverpool side of the estuary with new recreational walking and cycle paths and a monorail for commuters.

The concept includes a world-leading centre for hydropower research, which they argue would further enhance the region's excellence in science and innovation and support education into the technology.

However, one of the main obstacles to tidal projects, in addition to relatively high initial capital costs, is the perceived impact on the habitat of existing wildlife within estuaries.

The researchers believe any Mersey tidal project would need to offer alternative habitat to compensate for losses to existing mud flats - which are a major feeding ground for migratory birds.

However, they argue that concerns about impact to existing wildlife needs to be balanced against future environmental challenges.

Professor Aggidis said: "As with hydropower dams, tidal barrages could have a major impact on local environments, with concerns over biodiversity. Steps would need to be taken to balance the negative environmental impact against the potential to protect against flooding from future sea-level rises caused by global warming.

"We recognise that the total area of intertidal mud-flats that would be lost cannot be replaced. To compensate for the negative ecological effects of the barrage, wildlife will be integrated into the core of the design, which provide habitats to encourage increases in the variety of biodiversity on the Mersey estuary."

You mightn't think that the life of a dung beetle, a creature who eats poop every day of its short life, could get any worse, but you'd be wrong. Dung beetles, also known as rollers, pretty much live in manure. They can be found in a variety of environments-deserts, prairies, forests-and they subsist on poop. Dung beetles provide a highly useful service to the environment and to us. How? By simply living their lives, these valuable insects conduct "ecosystem services" that are important to agriculture, such as redistributing nutrients in the soil, controlling pests and reducing greenhouse gasses. Yet, dung beetles are one of the most threatened terrestrial animal species; and one of the main threats is the excessive use of veterinary medical products that are excreted in dung.

In an article recently published in Environmental Toxicology and Chemistry, lead author Daniel González-Tokman and his colleagues from the Institute of Ecology and the National Autonomous University of Mexico provided "the first evidence under natural conditions that native and exotic species of dung beetles are highly sensitive to different types of livestock management." The researchers showed that veterinary medications and herbicides used in intensive animal feeding facilities can alter the growth and development patterns of dung beetles, which can then reduce their ability to function and do good. The beetles' physiological responses to the chemicals were sex- and species-specific and contingent on both the type of livestock management used and the density of the cattle.

González-Tokman notes that studies such as these can help researchers "understand the underlying mechanisms of species decline in nature and enrich the strategies of livestock management with benefits for grassland ecological health."

If you are what you eat, it's a bad day for dung beetles living in or near intensive animal feeding facilities. Shrinking dung beetle populations mean steeper environmental and financial costs in agricultural regions, and that means it's a bad day for all of us, too.

From raindrops rolling off the waxy surface of a waterlily leaf, to the efficiency of desalination membranes, interactions between water molecules and water-repellent "hydrophobic" surfaces are all around us. The interplay becomes even more intriguing when a thin water layer becomes sandwiched between two hydrophobic surfaces, KAUST researchers have shown.

In the early 1980s, researchers first noted an unexpected effect when two hydrophobic surfaces were slowly brought together in water. "At some point, the two surfaces would suddenly jump into contact--like two magnets being brought together," says Himanshu Mishra from KAUST's Water Desalination and Reuse Center. Mishra's lab investigates water at all length scales, from reducing water consumption in agriculture, to the properties of individual water molecules.

Researchers were unable to explain the phenomenon at the molecular level, so in 2016, Mishra organized a KAUST conference on the subject. "We brought together leaders in the field--experimentalists and theorists--leading to intense debates on the understanding of hydrophobic surface forces," he says.

Part of the challenge was that the hydrophobic interaction is unique to water. "Gaining insights through other liquids or adding cosolvents to water is not feasible: the interaction is dramatically reduced or lost," explains Buddha Shrestha, a postdoctoral researcher in Mishra's lab.

Inspired by the conference, Mishra came up with the idea of comparing ordinary water with "heavy water," in which the hydrogen atoms are replaced by a heavier hydrogen isotope called deuterium.

"Our surface force measurements revealed that the attractive force was always approximately 10 percent higher in H2O than in D2O," says Sreekiran Pillai, a Ph.D. student in Mishra's lab. Collaborating with Tod Pascal at University of California San Diego, the team came up with an explanation.

The smaller an object, the less strictly it is governed by the laws of classical physics and the more it is subject to quantum effects. The tiny hydrogen atom is a quantum object--sometimes behaving like a particle, sometimes more like a wave. Deuterium, twice as heavy as hydrogen, is less subject to quantum effects. The consequence is that D2O is less destabilized than H2O when squeezed between two hydrophobic surfaces and the hydrogen bonds between water molecules get broken.

The discovery may have practical implications, Mishra says. "For example, these findings might aid the development of nanofluidic platforms for molecular separation."

"This is very impressive work that shows how quantum nuclear effects in water become substantial on the nanoscale," explains Professor Mischa Bonn, director of the Max Planck Institute for Polymer Research. "The results illustrate that there is still much to learn about water at the fundamental level, yet with direct relevance to nanoscale-confined water in, for instance, nanopores used for water purification and desalination."