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For anisotropic crystals, it has been known for many years that the birefringence effect rising from anisotropic refractive index should be considered for angle-resolved polarized Raman (ARPR) intensity. For opaque anisotropic crystals (OAC), not only the birefringence effect but also the dichroism effect from anisotropic absorption is responsible for ARPR intensity. With boomed emergence of in-plane anisotropic layered materials (ALMs), e.g., black phosphorus (BP), the investigations of their ARPR intensity have received great attention, which are commonly fitted by its Raman tensor and polarization of incident laser and scattered signal outside the crystals with a fitted complex Raman tensor due to dichroism or a fitted birefringence-induced phase delay. However, these approaches cannot be applicable to the case of ARPR intensity at oblique laser incidence because of the complex depth-dependent polarization and intensity of incident laser and scattered signal inside ALMs, and additional angle-dependent reflection and refraction at the interface between ALM lakes and air. Fundamentally, only real Raman tensor is generally involved if no magnetic perturbation occurs. Thus, this leaves an open question whether it is possible to reproduce ARPR intensity of OAC by only the real Raman tensor, especially for emergent ALMs.

Recently, a research team led by Prof. Ping-Heng Tan from Institute of Semiconductors, Chinese Academy of Sciences proposed a so-called birefringence-linear-dichroism (BLD) model to quantitively understand the ARPR intensity at both normal and oblique laser incidences on in-plane ALMs, by taking the bulk black phosphorus (BP) as an example. The depth-dependent polarization and intensity of incident laser and scattered signal induced by birefringence and linear dichroism are considered by complex refractive indexes along three principle axes, which is experimentally determined by the incident-angle resolved reflectivity. The experimental ARPR intensity can be well reproduced by the same set of real Raman tensors for a certain laser excitation, which are obtained from the relative Raman intensity along its principle axes. No fitting parameter is needed.

Fig.1 shows the setup for ARPR measurements at laser normal incidence and the corresponding ARPR intensity excited by 488 nm and 532 nm lasers. The good agreement between the calculated results (solid lines) experimental data (open circles) indicates that the ARPR intensity in ALMs can be quantitatively understand by the real Raman tensor once the birefringence and linear dichroism effects are considered based on the BLD model. In Fig.2, the ARPR intensity at oblique laser incidence can also be well reproduced by the same set of Raman tensors without any fitting parameters, which implies that the BLD model is possible to quantitatively reproduce the ARPR intensity of all ALMs for a given excitation wavelength under any scattering and polarization configurations.

The results suggest that the previously reported ARPR intensity of ultrathin ALM flakes deposited on a multilayered substrate at normal laser incidence can be also understood based on the BLD model by considering the depth-dependent polarization and intensity of incident laser and scattered Raman signal induced by both birefringence and linear dichroism effects within ALM flakes and the interference effects in the multilayered structures, which are dependent on the excitation wavelength, thickness of ALM flakes and dielectric layers of the substrate. This work can be generally applicable to any OAC, offering a promising route to predict and manipulate the polarized behaviors of related phonons.

Luxembourg, 10 September 2020 - In a seven-year research effort, an international team of scientists has clarified the cause for certain genetic forms of Parkinson's disease, and has identified potential pharmacological treatments. The interdisciplinary research team, led by Prof. Rejko Krüger, of the Luxembourg Centre for Systems Biomedicine (LCSB) of the University of Luxembourg, experimented on patient-based cell cultures in the laboratory. The new combination of active substances they identified will have to undergo clinical trials before they can be used to treat patients. The research team published its results today in the prestigious scientific journal Science Translational Medicine.

Lack of protein DJ-1 makes you sick

A protein called DJ-1 plays a crucial role in keeping nerve cells functioning. If the body is unable to produce ample amounts of DJ-1, important nerve cells die. The result is the onset of neuro-degenerative diseases such as Parkinson's. The production of important proteins like DJ-1 can be disrupted or halted permanently if the genetic blueprints or the production processes they encode are defective.

Now, Prof. Rejko Krüger's research team in Luxembourg has succeeded in identifying for the first time the importance of an error in the production process known as 'splicing' in the development of a certain form of Parkinson's disease. "In the patients, an essential tool for the assembly of the protein DJ-1 fails to dock properly," Krüger explains. "In scientific terms, we call that exon skipping. As a result of this defect, the protein doesn't get built at all." The research result offers an entirely new point of attack for treating this malfunction of protein synthesis with drugs. "This insight fundamentally changes our view of the causes of the disease and presents entirely new possibilities for treatment," says Dr Ibrahim Boussaad, LCSB scientist and first author of the scientific paper. "We could only gain this new understanding thanks to the skin cells from the patients," Boussaad emphasises.

Cell donation enables progress

The Luxembourg Parkinson's Study, initiated in 2015 (see also http://www.parkinson.lu), includes a group of 800 Parkinson's patients and 800 healthy control subjects. Thanks to the donation of skin cells taken by small biopsies, the researchers in Luxembourg were able to reprogram these cells to grow into nerve cells in vitro. These nerve cells are very similar to the neurons in affected regions of the donor's brain and can be used for analyses and tests in the laboratory. Because it is not possible to take neurons directly from the brain of patients, for health and ethical reasons, reprogramming is the only way to examine the clinical features of the patient's neurons in vitro. In scientific jargon, this is called a patient-based in vitro model, and is an important step in personalised medicine. Using this method, Prof. Krüger's team was able to explain the cause of the genetic form of Parkinson's disease in which the PARK7 gene is mutated. Prof. Thomas Gasser, a medical director at the Tübingen University Hospital and co-author of the paper, adds, "We are proud to have been able to contribute our expertise in the reprogramming of patient cells to this stem cell work of our colleagues in Luxembourg." Institutions from Germany, Italy and the USA collaborated in the research project.

Luxembourg's interdisciplinarity is a key to this success

Precise bioinformatics algorithms developed at the LCSB allowed the research team to immediately carry out an automated search for potential active substances for drug treatment. This yielded a hit in the form of the active compounds phenylbutyric acid and RECTAS (RECTifier of Aberrant Splicing). Administered in combination, these two active substances allow the cells in the test tube to effectively reactivate the production of the important protein DJ-1. "Only by combining numerous disciplines - from medical practice, to laboratory research, to computer science - could we understand the cause and at the same time identify active substances for a potential treatment," Prof. Rejko Krüger explains. He adds, "This kind of scientific progress 'Made in Luxembourg' is possible because all the necessary disciplines have been unified in Luxembourg for several years now." This work represents the high point to date of the PEARL program of the Luxembourg National Research Fund (FNR), through which the research of Prof. Krüger and his team is funded. The team of scientists especially expresses its gratitude to the people who are participating in the Luxembourg Parkinson's Study and who have made this research possible in the first place.

Since every process in lateral root development, including initiation, emergence and elongation is governed by auxin, the question arises of how auxin responds to the local presence of ammonium which is a major nitrogen source in natural and agricultural soils. "Our work shows that ammonium uptake by roots provokes pH changes that bring the plant hormone auxin into a protonated form allowing auxin to diffuse into outer root cells where it triggers the emergence of lateral roots", says Prof. von Wirén. These research results have now been published in the scientific journal Nature Plants.

Monitoring pH and auxin reporters indicate that ammonium uptake acidifies the root apoplast, i.e. the cell wall space, which increases import of protonated auxin into cortical and epidermal cells overlaying lateral root primordia, and subsequently promotes their emergence from the parental root. Although nitrogen-deficient plants also accumulate auxin in the root vasculature, like ammonium-supplied roots do, they have a more alkaline apoplast around the vasculature, which retains auxin in these tissues and prevents lateral root emergence. In simple words, local exposure of roots to ammonium makes roots losing control over the transport of this growth-promoting hormone.

Auxin import into cortical and epidermal cells enhances expression of genes involved in cell wall loosening, decreasing the mechanical resistance required for lateral root emergence. "Our study reveals that pH-dependent auxin diffusion can be recruited as a regulatory mechanism to coordinate the plasticity of root system architecture with fluctuating nutrient availabilities", says Prof. von Wirén. "To what extent this enhanced lateral root density promotes acquisition also of other nutrients remains to be shown."

In soils, ammonium-triggered lateral root emergence is not only relevant for shaping root system architecture under patchy nitrogen availability in natural environments, e.g. when roots touch organic matter-rich soil releasing ammonium through mineralisation, but also in agricultural plant production. "The increasing demand to reduce nitrogen fertilizer input is progressively met by banding sparingly soluble ammonium phosphate-based fertilizer strips in the soil", says Prof. von Wirén. Such local ammonium depots have been shown to enhance lateral root formation of field-grown crops as well as the mobilization and uptake of co-supplied phosphate. "Since local phosphate typically stimulates lateral root elongation while ammonium triggers lateral root emergence, it is tempting to speculate that knowledge on nutrient-dependent lateral root development can be further exploited to optimize the adaptation of crop root architecture to agricultural nutrient management practices."

Insect pollination is as important to Arctic plants as it is to plants further south. When flowers abound, the plants have to compete for pollinators. Researchers at the University of Helsinki reveal that higher temperatures cause the flowering periods of different plant species to pile up in time. As a consequence, climate change may affect the competitive relationships of plants.

The most attractive plant species steal the majority of pollinators, making other plants flowering at the same time suffer from poorer pollination.

"Most flowering plants are dependent on the pollination services provided by insects. Thus, plants need to time their flowering to periods of maximal pollinator abundances. On the other hand, plant species compete with each other for pollination. Thus, plant species flowering at the same time can affect each other's pollination success. Temperature is one of the most important environmental determinants of the onset of flowering. As the climate warms, plant species change their flowering periods, thereby changing their competition for pollinators," explains Mikko Tiusanen, researcher at the Faculty of Agriculture and Forestry, University of Helsinki, and lead scientist behind the study.

Avens is popular with pollinators - and competition is fierce

"We have been studying the relationship between plants and pollinators in North East Greenland, where the climate is warming twice as fast as the global average. The most common flowering plant in this region is Avens, a widespread and abundant flowering species. The shape of an Avens' flower is an open, white cup of nectar, irresistibly attractive to any pollinators around. In our comparisons, Avens was found to attract many more visitors than other plant species. When in bloom, it thus monopolizes insect pollination services at the expense of other plants in flower," says Tiusanen.

By studying the timing of flowering of different plant species under different environmental conditions, the researchers found that higher temperatures caused the flowering periods of different plant species to contract. In particular, the flowering of the Moss Campion advanced relative to the flowering of Avens. This affects the competition between the two species, since the flowering of Avens is directly reflected in how many insects carry Campion pollen: with more Avens in bloom, fewer insects carried the pollen of the Campion.

Global warming may thus affect competition between plant species for pollination services, thereby changing interactions between species. For example, overlap in flowering between a plant species and a more attractive competitor reduces pollination and may impair the species' chances of survival in the long run. This is likely to be a particular threat to rare plant species, as well as to flower species less attractive to insects, scientists speculate.

"To me, the Arctic represents a planetary research laboratory for studies of climate change," says Tomas Roslin, director of the research group spanning the University of Helsinki and the Swedish University of Agricultural Sciences (SLU). "The climate of this region is now changing twice as fast as the global average. What this means is that what happens in the Arctic today may later occur in the rest of the world. At the same time, relatively low species richness in the Arctic allows us to resolve their interactions in great detail. But scientific reasons are only half the arctic appeal. Northeast Greenland is one of the most beautiful areas in the world, and at the same time one of the largest uninhabited areas in the world. When studying insects here, you may even run into a polar bear. Such a combination keeps the researchers alert and awake."

Worldwide, cancer is the second leading cause of death - in 2018 alone, it claimed approximately 9.6 million lives, or one in six deaths. The development of cancer is incredibly complex and is controlled by an interplay of various factors - only recently, it became clear that the majority of human cancers such as cervical, gastrointestinal and breast among others, originate from adult stem cells becoming deregulated. These adult stem cells are present in many of our organs, where they provide a constant supply of cells to replace old and dead cells. Identifying the mechanisms of how these developmentally tightly regulated stem cells break free from their regulations is an important topic within the scientific community, including the Knoblich lab at IMBA.

One key step in tumorigenesis are the mechanics driving tumor cell initiation, which trigger their fate in becoming tumorigenic. They have, thus far, mainly been studied at gene regulation levels, by researching tumor suppressor genes MYC, p53 or KRAS. Metabolic changes within tumor cells are a well-known characteristic, but whether these are a consequence or the cause of tumor cell immortalization is still not known, and thus the focus of the most recent publication from Knoblich's team.

The researchers chose the fruit fly Drosophila melanogaster as tumor model - this established yet somewhat unconventional model organism boasts a long history in tumor studies, with discoveries in mutations of tumor suppressor genes dating back to the 1970s. Learnings from this simple model organism can then be used as a powerful tool as basis for further studies on human genes. In Drosophila, the scientists visualized the exact timepoint when tumor initiating cells became immortal and manipulated the process genetically - a feat which is not readily accomplished in mammalian tumors, due to their high complexity.

"We used a Drosophila neural stem cell (NSCs) tumor model, which is induced by the depletion of the well-known tumor suppressor called Brat. By using this model, we investigated whether the metabolism plays an active role in Brat tumor cell immortalization. Our findings in Drosophila will then be used as a basis for subsequent studies in human cells and lay the basis for mechanistic studies of human cancers," explains Jürgen Knoblich, IMBA group leader and Scientific Director.

Indeed, the researchers found Brat tumors to be highly oxidative, with higher oxygen consumption rates compared to normal brains. This proved to be quite the surprising discovery, as tumors are widely considered to be glycolytic.

In an additional exciting finding, the scientists from Knoblich's team found that the oxidative metabolism, which is a mitochondrial oxygen-dependent bioenergetic pathway, plays a key role in tumor cell immortalization. "We noticed that during tumor initiation, the mitochondrial membranes are fused. This drastic change in mitochondrial morphology leads to an increase in efficiency in oxidative phosphorylation, which explains why we found increased levels of NAD+ and NADH, two key molecules involved in bioenergetics," explains François Bonnay, postdoc in the Knoblich lab and first author of the study.

With additional experiments, the scientists showed that in the Drosophila brain, it is indeed the increased oxidative phosphorylation and NADH/NAD+ metabolism mediated by mitochondrial fusion which is absolutely necessary for tumor initiating cells to become immortal.

"Our findings overturn previous concepts about the biology of these tumors and open up an array of exciting follow up questions, including whether the mechanisms we just discovered in the fruit fly are also applicable to mammalian tumors. Questions we will also strive to answer are, how exactly does the NADH/NAD+ metabolism favour tumor cell immortalization, and does it achieve this via signalling, or through epigenetic changes? We are thrilled to advance our work in this field", says Knoblich.

A group of researchers from Charité - Universitätsmedizin Berlin have been able to show that maternal psychological wellbeing during pregnancy has a positive effect on newborn infants. Increased telomere length suggests a reduced rate of cell aging, which could have an effect on children's future health. Results from this study have been published in the American Journal of Psychiatry*.

A variety of pregnancy-related factors can have an impact on child development. Until now, researchers had primarily focused on the negative effects of stress, excess weight and poor nutrition - and how these might affect, say, placental function, premature birth and children's general health. At the cellular level, various pregnancy-related factors can have a direct impact on 'telomeres', cellular structures which protect the ends of chromosomes during cell division and can be lengthened by the enzyme telomerase. Telomere length is a molecular biology marker of cell aging which is linked to life expectancy and a range of age-related disorders. Although the effects of maternal stress have been widely studied, data on protective maternal factors and their positive effects on child development remain limited.

A group of researchers led by Prof. Dr. Sonja Entringer of Charité's Institute of Medical Psychology have been able to show that the mother's ability to cope with stress during pregnancy - her 'psychological resilience' - is linked to telomere length. The more positive a mother's attitude during pregnancy, the longer the children's telomeres. "Positive maternal psychological characteristics are biologically embedded and have a protective effect on the fetus," says Prof. Entringer.  

In an earlier study, the researchers examined the way in which maternal stress during pregnancy affects telomere length in their offspring. The current study, which saw Prof. Entringer's team work with a team of researchers led by Nobel Laureate Elizabeth Blackburn of the University of California and colleagues in Finland, had access to a large study population comprising 650 mother and child pairs. Telomere length was determined at birth, using cells from cord blood. Positive attitude in the face of stress was determined using a 'resilience index', which also took into account the pregnant women's psychological wellbeing and perceived social support.

"This study underlines the importance of maternal psychological wellbeing during pregnancy in terms of the developmental programming of lifelong health and disease, and the significance of improved psychosocial support measures during pregnancy," explains Prof. Entringer, who is also an Associate Professor at the University of California. Prof. Entringer was awarded a European Research Council 'Starting Grant' in 2016, which enabled her to set up and develop her own research group. The researchers are currently conducting more detailed investigations into the molecular mechanisms underlying the biological embedding of psychosocial effects in the cells of unborn children. As a next step, they are planning to conduct an interventional study on stress reduction in the day-to-day lives of pregnant women.

ITHACA, N.Y. - Cornell food scientists show in animal studies that a mother's high-fat diet may lead to more sweet-taste receptors and a greater attraction to unhealthy food in their offspring - resulting in poor feeding behavior, obesity in adulthood.

The researchers' findings were published July 31 in Scientific Reports.

Maternal exposure to a high-fat diet during the perinatal period - before the animal gets pregnant - appears to induce physical, detectable changes in the taste buds for offspring, said senior author Robin Dando, associate professor of food science in the College of Agriculture and Life Sciences.

"We see this is something actually happening in the taste buds themselves," Dando said. "Adult progeny, fed such a diet, have more sweet-taste receptors inside their taste buds than in the control group, whose mothers ate a steady, healthy diet."

Five weeks before mating, female mice were fed high-caloric, high-fat meals; other mice were also fed the high-fat diet from their pregnancy through lactation.

The progeny, weaned after the lactation period, ate healthy, high-quality laboratory chow. When the offspring became adults, the mice received their first taste of the high-fat diet.

"Up until then, the animals showed no difference between themselves and the control group," Dando said. "But as soon as the offspring of the moms who consumed the unhealthy diet had access to it, they loved it and they over-consumed it."

The offspring only encountered a high-fat diet by way of the maternal environment.

"If a mother has an unhealthy diet where she consumes a lot of calories through high-fat and sugary products," Dando said, "the offspring are going to have a predisposition for liking the unhealthy diet. The origin of this is not only the changes the brain, but there are other physical changes happening within the taste buds."

As Dando stressed, these results are in mice, but obesity in humans combined with an environmental component, the heritability is between 40% to 70%. "Obesity in the offspring is strongly predicted by the metabolic state of the parents," he said.

While the specific mechanism remains unclear, Dando said, the results introduce the concept of "taste" to the list of metabolic alterations arising from fetal programming.

"Our research adds to the evidence that the taste bud plays a role in the etiology of obesity," he said. "From a public health standpoint, improving our knowledge of prenatal and early postnatal factors that program obesity in offspring may provide insight into therapeutic targets to combat the obesity epidemic - a disease easier to prevent than to cure."

If you open up a pea pod, you will find that all of the peas inside are the same size and the same distance apart. The same is true of princess beans, runner beans and soybeans as well as various other peas and beans, and it also applies to non-pulses. This is surprising because both the seed size and number and the pod size differ substantially from one variety to the next.

A team of researchers based in Germany, Australia, Japan, the USA and Italy under the supervision of Prof. Dr. Rüdiger Simon from HHU's Institute of Developmental Genetics has analysed the genetic mechanisms behind this phenomenon. The team used different wild varieties of thale cress to examine the genetic processes taking place behind the initiation of ovules - the primordia from which seeds emerge after fertilisation - and the growth of the pod. These wild varieties are sourced from different locations. Thale cress or Arabidopsis thaliana is a model plant used in biology. Prof. Simon commented: "The individual seeds compete with each other for nutrients. To ensure that each seed gets an equal supply and can develop well, it is important that the seeds are spread as evenly as possible at equal distances in the pod."

There is considerable variation in fruit size and seed number even amongst the different wild varieties of Arabidopsis thaliana. However, the researchers also discovered a uniform genetic mechanism that controls seed position in the pod regardless of environmental factors such as temperature.

The team established that seed formation is controlled by several signalling pathways at precisely defined positions. These signalling pathways are activated by small secreted proteins from the EPFL family. These peptides are detected on the cell surface by receptors from the ERECTA family. One of the peptides, EPFL2, is formed between the developing ovules, where it adjusts the spacing between the seeds. Where this peptide is not present, the researchers found irregular spacing - meaning that adjacent seeds compete more for nutrients - or even ovule twinning, which generally results in neither ovule developing fully. EPFL2 and a very closely related peptide, EPFL9, also control fruit development. As a result, seed formation is closely linked to pod growth.

Dr. Nozomi Kawamoto, the first author of the study, highlighted another aspect: "The same signalling substances and receptors that we have identified as being responsible for relative pod size and seed spacing are also in charge of the spacing of leaf stomata and the microstructure of serrated leaves." A plant uses the stomata to regulate the exchange of gases with its environment. Dr. Kawamoto is carrying out post-doctoral research at Prof. Simon's Institute as part of the Cluster of Excellence on Plant Sciences CEPLAS in Düsseldorf.

NOAA/NASA's Suomi NPP satellite captured these series of images (made into an animated GIF) showing the winds changing direction on Sep. 06, 2020 when choking clouds of brown smoke began to billow and cascade into the Pacific Ocean. (Dates displayed in lower left hand corner.) By Sep. 10, the smoke cloud had traveled over 1,300 miles. The square miles of smoke in the image below totals 963,269. That estimate has been computed using the measurement tool within the NASA Worldview application.

A stunning 3.1 million acres have burned this year in California alone (per CAL fire), which is up from a total of 2.5 million acres as of Wednesday, Sep. 09, 2020. In addition, 805,314 acres have been lost in Oregon (State of Oregon Fires and Hotspots Dashboard, as of 9:30am EDT Sep. 11) and 500,000 acres (Northwest Interagency Coordination Center) in Washington state. Winds blowing through the west have been stoking fires and helping spread them quickly as evidenced in the growth of over a half million acres in less than two days. There have been 12 wildfire-related fatalities this year. Records have been shattered during this fire season and experts continue to blame drought, excessive heat and strong winds for this tragedy. Because the climate continues to change, scientists also believe that these types of fire events will not only continue but will worsen. Predictive meterologist for the National Interagency Fire Center, Nick Nausler, tweeted: "Multiple fires made 20-plus mile runs in 24 hours over the last few days in California, Oregon and Washington. Such distances traveled so quickly may not be all that rare in grassland fires. However, most of these fires are making massive runs in timber and burning tens of thousands of acres and in some cases 100,000-plus acres in one day. The sheer amount of fire on the landscape is surreal."

NASA's Earth Observing System Data and Information System (EOSDIS) Worldview application provides the capability to interactively browse over 700 global, full-resolution satellite imagery layers and then download the underlying data. Many of the available imagery layers are updated within three hours of observation, essentially showing the entire Earth as it looks "right now." Actively burning fires, detected by thermal bands, are shown as red points. Image Courtesy: NASA Worldview, Earth Observing System Data and Information System (EOSDIS). Caption: Lynn Jenner

An antibody test for the virus that causes COVID-19, developed by researchers at The University of Texas at Austin in collaboration with Houston Methodist and other institutions, is more accurate and can handle a much larger number of donor samples at lower overall cost than standard antibody tests currently in use. In the near term, the test can be used to accurately identify the best donors for convalescent plasma therapy and measure how well candidate vaccines and other therapies elicit an immune response.

Additional uses coming later that are likely to have the biggest societal impact, the researchers say, are to assess relative immunity in those previously infected by the SARS-CoV-2 virus and identify asymptomatic individuals with high levels of neutralizing antibodies against the virus.

The UT Austin research team, led by Jason Lavinder, a research associate in the Cockrell School of Engineering, and Greg Ippolito, assistant professor in the College of Natural Sciences and Dell Medical School, developed the new antibody test for SARS-CoV-2 and provided the viral antigens for this study via their UT Austin colleague and collaborator, associate professor Jason McLellan. Other UT Austin team members are Dalton Towers and Jimmy Gollihar. The work was published this week in The Journal of Clinical Investigation.

"This is potentially game-changing when it comes to serological testing for COVID-19 immunity," Lavinder said. "We can now use highly scalable, automated testing to examine antibody-based immunity to COVID-19 for hundreds of donors in a single run. With increased levels of automation, limited capacity for serological testing can be rapidly addressed using this approach."

The gold standard of COVID-19 antibody testing measures the amount of virus neutralizing (VN) antibodies circulating in the blood, because this closely correlates with immunity. However, this kind of antibody testing is not widely available because it's technically complex; requires days to set up, run and interpret; and needs to be performed in a biosafety level 3 laboratory.

The research team, therefore, looked to another type of test, called ELISA assays, that can be implemented and performed with relative ease in a high-throughput fashion and are widely available and extensively used in clinical labs across the world. The ELISA tests, or enzyme-linked immunosorbent assays, look at whether antibodies against specific SARS-CoV-2 proteins are present and produce a quantitative measure of those antibodies.

The goal of the study was to test the hypothesis that levels of antibodies that target two regions of the virus's spike protein--spike ectodomain (ECD) and receptor binding domain (RBD)--are correlated with virus neutralizing antibody levels, making these more accessible, easier-to-perform ELISA tests a surrogate marker to identify plasma donors with antibody levels above the recommended U.S. Food and Drug Administration threshold for convalescent plasma donation.

In collaboration with UT Austin, Penn State University and the U.S. Army Medical Research Institute of Infectious Diseases, study authors James M. Musser, M.D., Ph.D., and Eric Salazar, M.D., Ph.D., physician scientists at Houston Methodist, used the new test to evaluate 2,814 blood samples used in an ongoing study of convalescent plasma therapy. Houston Methodist became the first academic medical center in the nation to transfuse plasma from recovered individuals into COVID-19 patients.

The researchers found that the ELISA tests had an 80% probability or greater of comparable antibody level to VN levels at or above the FDA-recommended levels for COVID-19 convalescent plasma. These results affirm that all three types of tests could potentially serve as a quantitative target for therapeutic and prophylactic treatments.

Ultimately, the study successfully concluded that anti-RBD or anti-ECD antibody levels can serve as a surrogate for VN levels to identify suitable plasma donors and that these alternate ELISA tests may provide critical information about COVID-19 immunity.

"This research required a perfect storm at the university, which included the extraordinary combination of a world-famous coronavirus structural biology lab, a nimble and passionate visiting army scientist, and the highest echelons of the university's administration who were committed to bringing our extensive research programs to bear on the COVID-19 crisis," Ippolito said.

AUSTIN, Texas — After months of social distancing mandates, people are leaning heavily on technology for a sense of social connection. But new research from The University of Texas at Austin suggests people too often opt to send email or text messages when a phone call is more likely to produce the feelings of connectedness they crave.

In the study, people chose to type because they believed a phone call would be more awkward — but they were wrong, said Amit Kumar, a McCombs School of Business assistant professor of marketing, co-author with Nicholas Epley of the University of Chicago.

“People feel significantly more connected through voice-based media, but they have these fears about awkwardness that are pushing them towards text-based media,” Kumar said.

The research is online in advance in the Journal of Experimental Psychology.

In one experiment, researchers asked 200 people to make predictions about what it would be like to reconnect with an old friend either via email or phone, and then they randomly assigned them to actually do it. Even though participants intuited that a phone call would make them feel more connected, they still said they would prefer to email because they expected calling would be too awkward.

But the phone call went much better than an email, researchers found.

“When it came to actual experience, people reported they did form a significantly stronger bond with their old friend on the phone versus email, and they did not feel more awkward,” Kumar said.

In another experiment, researchers randomly assigned strangers to connect either by texting during a live chat, talking over video chat, or talking using only audio. Participants had to ask and answer a series of personal questions such as, “Is there something you’ve dreamed of doing for a long time? Why haven’t you done it?” or “Can you describe a time you cried in front of another person?”

Participants didn’t expect that the media through which they communicated would matter, and in this case they also predicted that they would feel just as connected to the stranger via text as by phone.

But the researchers found when they really interacted, people felt significantly more connected when they communicated by talking than by typing. And, again, they found it wasn’t more awkward to hear each other’s voices.

In fact, the voice itself — even without visual cues — seemed to be integral to bonding, the researchers found.

Confronting another myth about voice-based media, researchers timed participants reconnecting with their old friend. They found the call took about the same amount of time as reading and responding to email.

The researchers said the results both reveal and challenge people’s assumptions about communication media at a time when managing relationships via technology is especially important, Kumar said. “We’re being asked to maintain physical distance, but we still need these social ties for our well-being — even for our health.”

For more information about this research, read the McCombs Big Ideas feature story or watch the video interview.

Journal

Journal of Experimental Psychology

A new study out this week during the Global Week for Action on non-communicable diseases (NCDs) highlights that global public health regulation intended to tackle unhealthy diets, a key risk factor for NCDs, is being consistently opposed by the food and drinks lobby.

NCDs, such as heart disease, cancer, and diabetes, account for over 70% for global death and disability but failure to implement co-ordinated and targeted action has led to a growing problem – evidenced through the current obesity crisis facing much of the world.

The new research, from health policy analysts at Bath in collaboration with researchers from the universities of Edinburgh and São Paulo, and the World Public Health Nutrition Association, examined all food industry responses to consultations held by the World Health Organization (WHO) on NCD policy and governance between September 2015 and September 2018.

By evaluating responses across five separate consultations run by the WHO throughout this period, the work shows that, despite a rhetoric of support for public health, food industry groups consistently oppose effective regulations such as taxes and marketing restrictions, and advocate for weaker voluntary and partnership approaches instead.

Lobby groups also challenged established public health evidence about tackling NCDs. For example, the International Council of Beverages Associations which represents the soft drinks industry questioned the well-established link between sugar-sweetened beverages and obesity suggesting:

‘The overall weight of the scientific evidence on sugar and/or sugar-sweetened beverages show that they do not have a unique effect on body weight beyond their contribution to total calorie intake.’

In addition, the lobby group inaccurately argued that the world’s leading public health agency was not in a position to advise on health taxes:

‘Offering such policy advice in a field – economics and fiscal policy – far from WHO’s expertise is not in our opinion a prudent course of action.’

In fact, argue the researchers, the WHO includes among its staff many economists and the World Bank also promotes the use of health taxes.

The researchers suggest that the arguments used are similar to those deployed by the tobacco industry when the WHO started to take stronger action to regulate cigarettes in the early 2000s. These included claiming that regulation would not work or was not needed, and questioning the science and evidence underlying policies such as sugar-sweetened beverage taxation.

Recognising that good health is essential to development, the UN's landmark Sustainable Development Goals (SDGs) include a target to promote health and reduce premature mortality from NCDs by one third by 2030 (SDG 3). The COVID-19 pandemic, which affects people living with NCDs more severely, has shown how important this is.

Yet, the researchers highlight a possible tension between this goal, to improve health, and another, SDG 17, which promotes public-private partnerships. They document how food industry groups use the latter to promote industry involvement in policymaking, which for many is seen to be undermining attempts to improve health. A number of groups used SDG 17 to oppose a tool developed by the WHO to help member states protect nutrition programmes against conflicts of interest, arguing that such limitations on engagement with the food industry would not be coherent with the partnership aim promoted by the goal.

Lead author, Kathrin Lauber from the Tobacco Control Research Group at the University of Bath explains: “What happens at the WHO, and what doesn’t happen, is important to all of us. The agency’s guidelines can provide countries with a mandate to introduce crucial public health protections, which is why we see food and drink lobby groups pushing to keep the policy recommendations weak. Moreover, positioning collaboration with the commercial sector as a default risks impeding not only the work of the WHO as the UN’s key health agency, but also that of countries across the world working to reduce the burden of NCDs.”

Lucy Westerman, Policy and Campaigns Manager, NCD Alliance said: “As one of the many civil society advocates who engaged tirelessly in these same nutrition and noncommunicable disease (NCD) related WHO consultations and processes between 2015-2018, and who witnessed engagement of industry in some of these processes and related negotiations and outcomes, this analysis is extremely welcome and enlightening. The researchers' analysis illuminates but one of many ways in which such unhealthy commodity industries seek to dilute global health policy undermining efforts to ensure all people have access to healthy, nutritious diets. If we are to realise nutrition, NCD and Sustainable Development Goal targets and health for all, these industries cannot be allowed to dilute public health policy.”

This study was funded by the Roger and Sue Whorrod PhD Studentship. Professor Anna Gilmore and Kathrin Lauber are members of SPECTRUM, a UK Prevention Research Partnership (UKPRP) Consortium.

'Non-communicable disease governance in the era of the sustainable development goals: a qualitative analysis of food industry framing in WHO consultations' is published in the journal Globalization and Health https://globalizationandhealth.biomedcentral.com/articles/10.1186/s12992-020-00611-1.

Journal

Globalization and Health

DOI

10.1186/s12992-020-00611-1

New Haven, Conn. -- The universe's funhouse mirrors are revealing a difference between how dark matter behaves in theory and how it appears to act in reality.

Dark matter is the invisible glue that keeps stars bound together inside a galaxy. It makes up most of a galaxy's mass and creates an invisible scaffold that tethers galaxies to form clusters.

Dark matter does not emit, absorb, or reflect light. It does not interact with any known particles. Its presence is known only through its gravitational pull on visible matter in space.

Although dark matter is lightly smeared throughout the universe, it is heaped in regions of space called galaxy clusters. Each of these massive clusters, held together by gravity, is made up of about 1,000 individual galaxies -- each of which carries its own dollop of dark matter.

In a new study in the journal Science, Yale astrophysicist Priyamvada Natarajan and a team of international researchers analyzed Hubble Space Telescope images from several massive galaxy clusters and found that the smaller dollops of dark matter associated with cluster galaxies were significantly more concentrated than predicted by theorists.

The finding implies there may be a missing ingredient in scientists' understanding of dark matter.

"There's a feature of the real universe that we are simply not capturing in our current theoretical models," said Natarajan, a senior author of the study and a professor of astronomy and physics at Yale. "This could signal a gap in our current understanding of the nature of dark matter and its properties, as this exquisite data has permitted us to probe the detailed distribution of dark matter on the smallest scales."

Astronomers are able to "map" the distribution of dark matter within galaxy clusters via the bending of light the galaxies produce -- a concept called gravitational lensing. Like a funhouse mirror, gravitational lensing distorts the shapes of background galaxies that appear in telescope images of cluster galaxies. The higher the concentration of dark matter in a cluster, the more dramatic the observed lensing effects.

The researchers used images from NASA's Hubble Space Telescope, coupled with spectroscopy from the European Southern Observatory's Very Large Telescope, to produce high-fidelity dark-matter maps.

A 3D view of the data showed the presence of dark matter hills,
mounds, and valleys. From this perspective the mapped dark matter looks like a mountain range, with peaked regions. The peaks are the dollops of dark matter associated with individual cluster galaxies.

The especially high quality of the study's data allowed the researchers to test whether these dark matter landscapes matched theory-based computer simulations of galaxy clusters with similar masses, located at roughly the same distances.

What they discovered was that the simulations did not show any of the same level of dark-matter concentration on the smallest scales -- the scales associated with individual cluster galaxies.

"To me personally, detecting a gnawing gap -- a factor of 10 discrepancy in this case -- between an observation and theoretical prediction is very exciting," Natarajan said. "A key goal of my research has been testing theoretical models with the improving quality of data to find these gaps. It's these kinds of gaps and anomalies that have often revealed that either we were missing something in the current theory, or it points the way to a
brand-new model, which will have more explanatory power."

Natarajan has spent more than a decade confronting theoretical models of dark matter with data from gravitational lensing. "The quality of data and the sophistication of models have only now converged to permit stress testing of the cold dark matter paradigm, and it has revealed a crack," she said.

Males and females share the vast majority of their genomes. Only a sprinkling of genes, located on the so-called X and Y sex chromosomes, differ between the sexes. Nevertheless, the activities of our genes--their expression in cells and tissues--generate profound distinctions between males and females.

Not only do the sexes differ in outward appearance, their differentially expressed genes strongly affect the risk, incidence, prevalence, severity and age-of-onset of many diseases, including cancer, autoimmune disorders, cardiovascular disease and neurological afflictions.

Researchers have observed sex-associated differences in gene expression across a range of tissues including liver, heart, and brain. Nevertheless, such tissue-specific sex differences remain poorly understood. Most traits that display variance between males and females appear to result from differences in the expression of autosomal genes common to both sexes, rather than through expression of sex chromosome genes or sex hormones.

A better understanding of these sex-associated disparities in the behavior of our genes could lead to improved diagnoses and treatments for a range of human illnesses.

In a new paper in the PERSPECTIVES section of the journal Science, Melissa Wilson reviews current research into patterns of sex differences in gene expression across the genome, and highlights sampling biases in the human populations included in such studies.

"One of the most striking things about this comprehensive study of sex differences," Wilson said, "is that while aggregate differences span the genome and contribute to biases in human health, each individual gene varies tremendously between people."

Wilson is a researcher in the Biodesign Center for Mechanisms in Evolution, the Center for Evolution and Medicine, and ASU's School of Life Sciences.

A decade ago, an ambitious undertaking, known as the Genotype-Tissue Expression (GTEx) consortium began to investigate the effects DNA variation on gene expression across the range of human tissues. Recent findings, appearing in the Science issue under review, indicate that sex-linked disparities in gene expression are far more pervasive than once assumed, with more than a third of all genes displaying sex-biased expression in at least one tissue. (The new research highlighted in Wilson's PERSPECTIVES piece describes gene regulatory differences between the sexes in every tissue under study.)

Sex-linked differences in gene expression are shared across mammals, though their relative roles in disease susceptibility remain speculative. Natural selection likely guided the development of many of these attributes. For example, the rise of placental mammals some 90 million years ago may have led to differences in immune function between males and females.

Such sex-based distinctions arising in the distant past have left their imprint on current mammals, including humans, expressed in higher rates of autoimmune disorders in females and increased cancer rates in males.

Despite their critical importance for understanding disease prevalence and severity, sex differences in gene expression have only recently received serious attention in the research community. Wilson and others suggest that much historical genetic research, using primarily white male subjects in mid-life, have yielded an incomplete picture.

Such studies often fail to account for sex differences in the design and analysis of experiments, rendering a distorted view of sex-based disease variance, often leading to one-size-fits-all approaches to diagnosis and treatment. The authors therefore advise researchers to be more careful about generalizations based on existing databases of genetic information, including GTEx.

A more holistic approach is emerging, as researchers investigate the full panoply of effects related to male and female gene expression across a broader range of human variation.

According to the Global Hygiene Council's (GHC) public health experts, following a risk-based approach to home hygiene is essential to help curb the growing threat of antibiotic resistance.

It is estimated that rates of resistance to commonly-used antibiotics could exceed 40-60% in some countries by 2030. With AMR set to claim the lives of 10 million by 2050 if no action is taken, the GHC's experts are calling for a review of hygiene practices in homes and everyday life to ensure that they are effective and appropriate to the urgent public health issues we currently face, such as AMR and COVID-19.

In a new Position Paper developed by the GHC and published in the latest edition of the American Journal of Infection Control, the experts set out the evidence showing that better hygiene in our homes and everyday lives plays an essential part in tackling antibiotic resistance. Good hygiene contributes to the fight against AMR in two ways, by preventing infection, thereby reducing the need for antibiotic prescribing and preventing person to person spread of infections which are antibiotic resistant.

The paper reviews evidence that to minimize the spread of infections in home and community settings, a more focused approach to hygiene based on risk assessment is needed. For example, removing infection-spreading germs from high-risk surfaces and hands at critical times, such as when preparing food and using the toilet, has been proven to minimise the spread of infections from person to person. One intervention study demonstrates that improved hand hygiene amongst a group of children in a day centre can reduce the need for antibiotic use for common respiratory infections by 30%.

As Professor Sally Bloomfield, public health expert and contributor to the paper, explains; "Instead of deep-cleaning our homes, we urge everyone to maintain this evidence-based Targeted Hygiene approach in our homes and everyday lives, focusing on the times and places harmful microbes are most likely to spread, to not only help contain the spread of coronavirus now but ongoing to help tackle AMR."

To coincide with the publication of the Paper, the GHC has launched a Manifesto calling upon national and international policy makers, health agencies and healthcare professionals to further recognise the importance of hygiene in the home and everyday life settings and acknowledge the following:

1/ National AMR committees, responsible for implementing national AMR plans, should recognise that improved hand and surface hygiene in the home and community are key to minimise the spread of infections and as a consequence the consumption of antibiotics, which will then help in the fight against AMR. To achieve this, recommendations for improved hygiene in the wider community should be included in global AMR action plans by 2022 and in all national plans by 2025.

2/ IPC advice, guidance and education for HCPs on hand and surface hygiene and its relation to AMR should not be limited to healthcare settings, but also include recommendations to influence the wider community with immediate effect.

3/ Relevant medical associations should ensure messaging around home and community hygiene is cascaded to members through amending on-going and existing AMR training and education.

With evidence to show that home and community hygiene urgently needs to be taken more seriously, it is time for the global community to collaborate and recognise that reducing the need for antibiotic prescribing and the circulation of AMR strains in healthcare settings cannot be achieved without also reducing the circulation of infections and AMR strains in the community.