Culture

University of Sheffield physicists take a step towards understanding why the universe is mostly matter and not antimatter

Research by an international collaboration indicates a difference in the behaviour of neutrinos and antineutrinos

The research is a major step forward and could further our understanding of the universe

Physicists from the University of Sheffield have taken a step towards understanding why the universe is made of mostly matter and not antimatter, by studying the difference between the two.

Findings from the T2K experiment, a large international collaboration of more than 350 scientists including a team from Sheffield, indicate a difference between the fundamental behaviour of elusive elementary particles, neutrinos, and of antineutrinos - their antimatter counterparts.

The research, published in Nature, is a major step forward in the study of the difference between matter and antimatter and could help to further our understanding of why the universe is mostly made up of matter and not equal parts of matter and antimatter.

The T2K Collaboration used the SuperKamiokande detector to observe neutrinos and antineutrinos which were generated 295km away at the Japanese Proton Accelerator Research Complex (J-PARC).

As they travel through the Earth, these particles oscillate between different physical properties known as flavours. The T2K collaboration found a mismatch in the way neutrinos and antineutrinos oscillate by recording the numbers that reached SuperKamiokande with a flavour different from the one they had been created with.

The observation of the difference in behaviour between neutrinos and antineutrinos is due to a so-called asymmetry in their physical properties. Measuring this asymmetry, known as charge-conjugation and parity reversal (CP) violation, may help us understand the origin of the current prevalence of matter over antimatter in the Universe.

Professor Lee Thompson, from the University of Sheffield's Department of Physics and Astronomy, said: "Astronomers find that the matter in the universe is overwhelmingly just that: matter, with positively charged atomic nuclei surrounded by negative electrons.

"When particle physicists make new particles in accelerators, they always find that they produce particle-antiparticle pairs: for every negative electron, a positively charged positron. So why isn't the universe 50 per cent antimatter? This is a long-standing problem in cosmology - what happened to the antimatter?

"This work brings together particle physics and cosmology - by studying neutrinos, the most elusive of the elementary particles, we learn something about the largest of astrophysical topics, the universe itself."

Professor Lee Thompson, Dr Susan Cartwright and Dr Matthew Malek from the University of Sheffield's Department of Physics and Astronomy made up the team from Sheffield.

The measurements found during the experiment strengthen previous observations and pave the way towards future discoveries. A new generation of experiments under construction, involving a team of particle physicists at Sheffield, might provide an answer to the problem of the missing antimatter in the next 10 years.

Milan, 6 April 2020 - Can 3D Printers support extra-terrestrial colonisation in Space?

One of the major challenges related to space exploration is the development of production technologies capable of exploiting the few resources available in extra-terrestrial environment. Laser 3D printing of lunar dust may be the answer to such queries. Reduction of elevated supply chain costs and times connected to space exploration were amongst the main drivers which brought to the joint investigation on behalf of the Department of Mechanical Engineering and Department of Aerospace Science and Technology of the Politecnico di Milano to on the feasibility of 3D printing a lunar regolith simulant (NU-LHT-2M).

Additive manufacturing or 3D printing systems may allow the realisation of components when required, employing locally available resources and through a direct conversion from the digital CAD geometry to the final object. 3D printing can thus enable the manufacturing of lightweight structures, with improved performance (heat exchange, impact resistance, etc.) and greater reliability due to significant reductions in the number of components.

The research was coordinated by Professor Bianca Maria Colosimo, (Department of Mechanical Engineering), and was carried out with support of the Italian Space Agency (ASI) and European Space Agency (ESA). The project saw the collaboration of a team from the Department of Mechanical Engineering who worked on the development of the laser 3D printer led by Prof. Barbara Previtali with the support of Dr. Ali Gökhan Demir, Leonardo Caprio and Eligio Grossi (Department of Mechanical Engineering), who developed the prototype 3D laser beam printer. Concurrently, a team from the Department of Aerospace Science and Technology composed by Prof. Michéle Lavagna, Prof. Giuseppe Sala and Lorenzo Abbondanti-Sitta contributed by providing the lunar dust simulant, cooperating during the various experimental campaigns and conducted materials characterization of the final products.

First author of the study "Determining the feasible conditions for processing lunar regolith simulant via laser powder bed fusion", published in the peer-reviewed journal Additive Manufacturing, is Leonardo Caprio, PhD candidate in Advanced and Smart Manufacturing at the Politecnico di Milano. He stated that "a stable system architecture based on the use of an efficient laser source is fundamental in order to enable the technological transfer from a prototypal system to space applications". The research demonstrated that lunar powder or regolith could be 3D printed through the optimisation of processing conditions and laser parameters. Following the research's positive results, it was possible to define guidelines for the design of a future 3D printing system for use in space.

The ASI-Politecnico Agreement Project Manager Danilo Rubini said: "The Italian Space Agency, which has training and research support as its cornerstone, sees partnerships with universities of national excellence as one of its priorities." The partnership with the Politecnico di Milano is a perfect example of cooperation between institutions and universities which starting from basic research to generate technologies and applications which contribute to socio-economic growth. If we consider the impact that space activities and satellite data can have on our daily lives we can see how Space is an always growing enabling element. Technological developments such as 3D printers and Additive Manufacturing when applied to space elements, such as the lunar regolith, can contribute to new lunar missions through In-Situ-Resource-Utilisation (ISRU) but may also help us to understand how to improve the management of terrestrial resources."

Osaka, Japan - Fertilization is a fundamental process in sexual reproduction when the combination of male and female gametes blends genetic material to create a new unique individual. Now, researchers from Japan have identified a new factor that may help orchestrate this vitally complex life event.

In a recent study, researchers from Osaka University and Baylor College of Medicine have identified a novel protein that takes part in sperm-oocyte membrane fusion during fertilization, and named it Fertilization Influencing Membrane Protein (FIMP).

The human body comprises trillions of cells all derived from a single fertilized ovum. Sperm-oocyte fusion is a critical event in mammalian fertilization and three proteins that facilitate this are known. The sperm membrane protein IZUMO1 was discovered in 2005 by this research team and named for a Shinto shrine celebrating marriage. Its counterpart, the oocyte membrane protein JUNO discovered nine years later was named after the Roman goddess of fertility. Together they interact to form a protein complex, with the oocyte tetraspanin protein CD9 contributing. As three proteins cannot explain the complex molecular interactions involved, the search was on for other factors.

"We focused on the testis-specific 4930451I11Rik gene using CRISPR/Cas9-mediated genome editing technology to generate mutant 'knock out' mice with selectively inactivated or 'turned off' genes," explains Dr Yoshitaka Fujihara, Associate Professor at the Research Institute for Microbial Diseases, and lead author of the study. "Although IZUMO1 was present in 4930451I11Rik knockout spermatozoa, they were unable to fuse with oocytes and the KO males proved severely subfertile."

The 4930451I11Rik gene encodes two protein variants, a transmembrane (TM) isoform and a secreted isoform. CRISPR/Cas9-mediated deletion and transgenic rescue showed that only the TM isoform is essential for sperm-oocyte fusion. The researchers named the TM isoform 'Fertilization Influencing Membrane Protein' and clarified that it is essential for fertilization, functioning in membrane fusion through a different pathway or stage from IZUMO1. Fluorescence mCherry tagging localized FIMP to the sperm equatorial segment where sperm-oocyte fusion occurs.

Professor Masahito Ikawa, co-discoverer of IZUMO1 and senior author, speculates on the implications and future trends of their research. "Our findings support a potential role of human FIMP in sperm function. Further studies are needed to examine the cause of male infertility in Fimp knockout mice and to clarify the interaction of similar type I transmembrane proteins localized on the sperm head. This knowledge could be used to develop novel in vitro and in vivo infertility treatments as well as non-hormonal male-specific contraceptives."

A healthy body is home to a healthy mind: sporting activity can improve your cognitive performance. However, there are numerous different types of sports and a wide range of exercise and training. Which type and how much exercise will keep your mind in top shape? This is the question that has been explored by researchers at the University of Basel and their colleagues at the University of Tsukuba in Japan through a large-scale analysis of the scientific literature. They have used this analysis to derive recommendations that they recently published in the journal Nature Human Behaviour.

Coordinated sports are particularly effective

The research group with the participation of Dr. Sebastian Ludyga and Professor Uwe Pühse evaluated 80 individual studies to identify a few key characteristics. Endurance training, strength training or a mix of these components seem to improve cognitive performance. However, coordinated and challenging sports that require complex movement patterns and interaction with fellow players are significantly more effective. "To coordinate during a sport seems to be even more important than the total volume of sporting activity," explains Ludyga.

A higher total extent of activity does not necessarily lead to a correspondingly higher level of effectiveness for mental fitness. Longer duration per exercise unit promises a greater improvement of cognitive performance only over a longer period of time.

All age groups benefit

Just like our physical condition, cognitive performance changes over the course of our lives. There is great for potential for improvement during childhood (cognitive development phase) and during old age (cognitive degradation phase). However, the research group of the Department of Sport, Exercise and Health (DSBG) at the University of Basel was unable to find an indicator of different levels of effectiveness of sporting activities within the varying age groups.

Furthermore, sporting activities from primary school age to later age do not have to be fundamentally different in order to improve cognitive performance. Different age groups can thus be combined for a common goal during sports. "This is already being implemented selectively with joint exercise programs for children and their grandparents," says Pühse. Such programs could thus be further expanded.

Intense sports sessions for boys and men

The same volume of sports activity has a different effect on physical fitness for men and women, as we are already aware. However, the research group has now been able to verify this for mental fitness. Men accordingly benefit more from sporting activity.

Differences between the sexes are particularly evident in the intensity of movement, but not in the type of sport. A hard workout seems to be particularly worthwhile for boys and men. Paired with a gradual increase in intensity, this leads to a significantly greater improvement in cognitive performance over a longer period of time.

In contrast, the positive effect on women and girls disappears if the intensity is increased too quickly. The results of the research suggest that they should choose low to medium intensity sporting activities if they want to increase their cognitive fitness.

CHEOPS is a joint mission by the European Space Agency (ESA) and Switzerland, under the leadership of the University of Bern in collaboration with the University of Geneva (UNIGE). After almost three months of extensive testing, with part of it in the midst of the lockdown to contain the coronavirus, on Wednesday, March 25, 2020, ESA declared the CHEOPS space telescope ready for science. With this achievement, ESA has handed over the responsibility to operate CHEOPS to the mission consortium, which consists of scientists and engineers from approximately 30 institutions in 11 European countries.

Successful completion of the CHEOPS test phase despite the coronavirus crisis

The successful completion of the test phase took place in very challenging times, with essentially all the mission team being required to work from home towards the end of the phase. "The completion of the test phase was only possible with the full commitment of all the participants, and because the mission has an operational control system that is largely automated, allowing commands to be sent and data to be received from home," explains Willy Benz, Professor of Astrophysics at the University of Bern and Principal Investigator of the CHEOPS mission.

A team of scientists, engineers and technicians put CHEOPS through a period of extensive testing and calibration from the beginning of January until the end of March. "We were thrilled when we realized that all the systems worked as expected or even better than expected," explains CHEOPS Instrument Scientist Andrea Fortier from the Univerisity of Bern, who led the commissioning team of the consortium.

Meeting high requirements on measuring accuracy

The team began by focusing on the evaluation of the photometric performance of the space telescope. CHEOPS has been conceptualized as a device of exceptional precision capable of detecting exoplanets the size of planet Earth. "The most critical test was in the precise measurement of the brightness of a star to a variance of 0.002% (20 parts-per-million)," explains Willy Benz. This precision is required so as to clearly recognize the dimming caused by the passage of an Earth-sized planet in front of a Sun-like star (an event known as a "transit", which can last several hours). CHEOPS was also required to demonstrate its ability to maintain this degree of precision for up to two days.

CHEOPS surpasses the requirements

To verify this, the team focused on a star known as HD 88111. The star is located in the Hydra constellation, some 175 light years away from Earth, and it is not known to host planets. CHEOPS took an image of the star every 30 seconds for 47 consecutive hours (see Figure 1). Every image was carefully analyzed, initially using a specialized automatic software package, and subsequently by the team members, to determine in each image the brightness of the star as accurately as possible. The team had expected the brightness of the star to change during the period of observation due to a variety of effects, such as other stars in the field of view, the tiny jitter motion of the satellite, or the impact of cosmic ray hits on the detector.

The results of the 5,640 photos taken by CHEOPS over 47 hours are shown in Figure 2 as a "light curve". The curve depicts the change over time in the brightness measurements from all the images, showing a root-mean-square scatter of 0.0015% (15 parts-per-million). "The light curve measured by CHEOPS was pleasingly flat. The space telescope easily surpasses the requirement for being able to measure brightness to a precision of 0.002% (20 parts-per-million)," explains Christopher Broeg, Mission Manager for the CHEOPS mission at the University of Bern.

An exoplanet that would float

The team observed other stars, including some known to host planets (these are called exoplanets). CHEOPS focused on the planetary system HD 93396 which is in the Sextans constellation, some 320 light years away from Earth. This system consists of a giant exoplanet called KELT-11b, which was discovered in 2016 to orbit this star in 4.7 days. The star is almost three times the size of the sun.

The team chose this particular system because the star is so big that the planet takes a long time to pass in front of it: in fact, almost eight hours. "This gave CHEOPS the opportunity to demonstrate its ability to capture long transit events otherwise difficult to observe from the ground, as the 'astronomical' part of the night for ground-based astronomy usually takes less than eight hours," explains Didier Queloz, professor at the Astronomy Department of the Faculty of Science at the University of Geneva and spokesperson of the CHEOPS Science Team. The first transit light curve of CHEOPS is shown in Figure 3, where the dip due to the planet occurs approximately nine hours after the he beginning of the observation.

The transit of KELT-11b measured by CHEOPS enabled determining the size of the exoplanet. It has a diameter of 181,600 km, which CHEOPS is able to measure with an accuracy of 4'290 km. The diameter of the Earth, in comparison, is only approximately 12,700 km, while that of Jupiter - the biggest planet in our solar system - is 139,900 km. Exoplanet KELT-11b is therefore bigger than Jupiter, but its mass is five times lower, which means it has an extremely low density: "It would float on water in a big-enough swimming pool," says David Ehrenreich, CHEOPS Mission Scientist from the University of Geneva. The limited density is attributed to the close proximity of the planet to its star. Figure 4 shows a drawing of the first transit planet system to be successfully observed by CHEOPS.

Benz explains that the measurements by CHEOPS are five times more accurate than those from Earth. "That gives us a foretaste for what we can achieve with CHEOPS over the months and years to come," continues Benz.

Several hundred thousand salmon swim closely together in fish farms. For at least some time, the fish farmer and the fish have the same goal: to keep the fish healthy, eating and growing. Therefore it is necessary to provide fish with environmental conditions, where the stress level is low, parasites do not pose a risk to their health and there is enough food. Stressed and sick fish do not eat or grow or bring profit to the fish farmer.

The Head of TalTech Centre for Biorobotics, Professor Maarja Kruusmaa says, "In order to effectively observe fish in their natural state, a technology is needed, which would enable reaching each nook of the fish farm, where e.g. frightened specimens might be hiding. It must be observed whether the feed reaches all the fish or only the more aggressive alpha specimens, whether the fish have parasites or any other health problems, etc."

The behaviour of fish in a fish cage is traditionally investigated by using human divers or underwater robots. Divers' work is expensive and, most importantly, fish are afraid of the invader and therefore by diving it is not possible to observe fish in their natural state. The same problem applies to use of big underwater robots.

Therefore, researchers from Tallinn University of Technology, Estonian University of Life Sciences and Norwegian University of Science and Technology, in collaboration with the research organization SINTEF and one of the world's largest fish farm companies SalMar, conducted experiments to find out what kind of inspection robots should be used for observing fish in their natural state. The behavior of fish in the presence of a diver and different robots was analyzed and compared to identify what features are important in the development of robots for more efficient monitoring of animals.

The results of the experiments showed that fish behave very calmly and naturally in the presence of the small and slowly moving robot turtle U-CAT invented by TalTech biorobotics researchers. A conventional commercial underwater robot scares fish off and forces them to flee rapidly and a diver does not get close enough to the fish at all to observe them underwater, while U-CAT is able to get closest to the fish in the fish farm and provide valuable insight of their state. The study provided other useful cues for the development of robots intended for observing animals, such as what colour should the robot be or how should it move.

Professor Maarja Kruusmaa says, "Robot-human interactions have been investigated for decades, but animal-robot interactions and communication is almost unexplored. However, these studies are of considerable importance: they would inspire advances in environmental monitoring and agriculture automation, and would help to build robots facilitating wildlife research."

Fish farming has a larger market share compared to wild fishing worldwide and the share is increasing steadily, constituting currently an industry with the turnover of over 3 billion dollars.

Psilocybin mushrooms have been found to have minimal harmful effects and could potentially benefit those with depression. But they remain illegal even though they offer a groundbreaking alternative to several under-treated psychological conditions.

Nevertheless, psychedelics are currently riding a wave of positive momentum brought on by cannabis, and if psilocybin gets approved as a pharmaceutical drug, production in yeast appears to be the most commercially viable option.

"It's infeasible and way too expensive to extract psilocybin from magic mushrooms and the best chemical synthesis methods require expensive and difficult to source starting substrates. Thus, there is a need to bring down the cost of production and to provide a more consistent supply chain," says Nick Milne, former Postdoc at DTU Biosustain and CSO and Co-founder of Octarine Bio.

Bio-based production of psilocybin has gained big interest and researchers have already proved small-scale production in E. coli. However, production in bacteria comes with a wide range of concerns which can be addressed by using yeast instead.

In yeast, the scientists prove that psilocybin can be produced de novo, which means that you can produce the molecule by simply growing the yeast with sugar and other nutrients, without the need to add any other starting substrates.

Producing psilocybin de novo in E. coli is difficult since a key enzyme in the biosynthetic pathway doesn't work in bacteria, and so to get around this problem you need to add an expensive starting substrate, making the whole production process too costly.

"Since yeast and Psilocybe mushrooms are quite closely related species, this enzyme works very well in yeast, providing a much more cost-efficient alternative," says group leader at DTU Biosustain Irina Borodina.

Additionally, yeast also performs better in large-scale fermentation due to its long history in the beer brewing process, and also in the purification process since E. coli produces additional potentially harmful compounds that you would not like to have in your final product.

Interest in research into the effects of psilocybin, a psychedelic drug, has increased significantly in recent years due to its promising therapeutic effects in neuropsychiatric disorders such as depression, anxiety and addiction.

It is widely accepted that the brain's powerful ability to adapt its behaviour flexibly is largely due to the neurotransmitter system. Psilocybin is the substance responsible for the psychoactive effect caused by nearly 200 species of fungi. This substance has a particular affinity for serotonin receptors found primarily in the brain, but also in other parts of the body such as the stomach. Upon consumption, psilocybin selectively changes the function of serotonin receptors, thus generating an altered state of consciousness characterized by the dissolution of the ego, changes in the quality and attribution of thoughts, impaired visual and sensory perception, and greater awareness of repressed memories.

An international team of researchers has developed a computational biophysical model of the entire brain that integrates real data about its anatomical structural connectivity, the functional dynamics of neurons and a map which shows the concentration of serotonin receptors in various brain regions.

This international research, published on 13 April in the journal Proceedings of the National Academy of Sciences, was led by Gustavo Deco, ICREA research professor and director of the Center for Brain and Cognition at the Department of Information and Communication Technologies (DTIC) at UPF, with the participation of Josephine Cruzat, a member of his team, Morten L. Kringelbach, a neuroscientist at the University of Oxford (UK), and other scientists from research centres in Germany, Denmark, the US, Portugal and the UK.

This work has shown that the new dynamic model of the whole brain is capable of addressing one of the major challenges in neuroscience: to explain the paradoxical flexibility of brain function despite having a fixed anatomical structure

Study of psilocybin's mechanisms of action in humans

This theoretical and experimental study modelled the interaction between neuronal and neurotransmitter systems throughout the brain to explain how psilocybin affects brain activity. To study the drug's mechanisms of action, Morten Kringelbach, Josephine Cruzat and Gustavo Deco analysed data from functional magnetic resonance imaging (fMRI) in 16 healthy subjects. In the experiment, participants were given small doses of psilocybin intravenously or saline solution (placebo effect) while in the scanner, to measure their brain function. The experimental part of the study was carried out at Imperial College London under the direction of Robin Carthart-Harris, co-author of the study.

The functional data acquired under the conditions of placebo and psilocybin were then combined with data from diffusion magnetic resonance imaging (dMRI) capturing brain structure by describing the anatomical connections between the different brain regions; and with data on the density of serotonin receptors estimated by positron emission tomography (PET).

The integration of neuronal and neurotransmitter systems at whole-brain level is important to fully explain the effects of psilocybin on brain activity

As explained by Deco and Cruzat, co-authors of the work and experts in computational neuroscience, "the computational simulations performed in this study revealed that the integration of neuronal and neurotransmitter systems at the whole-brain level is important to fully explain the effects of psilocybin on brain activity, specifically through the stimulation of serotonin receptors 5 -HT2A, involved in psychoactive modulation".

Overall, the remarkable flexibility of human brain function depends crucially on the bidirectional dynamic participation of neuronal and neurotransmission systems. According to the authors, this new approach provides a better and deeper understanding of the effects of psilocybin on the brain and may lead to the development of new treatments for neuropsychiatric diseases such as depression, anxiety and addiction.

Primary care health workers now have a guide for conducting remote consultation of suspected COVID-19 patients, developed by a team of researchers from Singapore and the UK.

During the COVID-19 pandemic, face-to-face examination of patients has been restricted in many countries as people self-isolate at home, leading to an increasing demand for telemedicine.

To help doctors adapt to the need for more remote assessments, a team comprising Associate Professor Josip Car at the Nanyang Technological University, Singapore (NTU Singapore), Professor Trisha Greenhalgh from the University of Oxford and Professor Gerald Koh at the National University of Singapore collaborated to develop a guide.

The work was published in peer-reviewed medical journal The BMJ in March, and has since been incorporated in the UK-based National Institute for Health and Care Excellence (NICE) rapid guideline on COVID-19, on managing suspected or confirmed pneumonia in adults in the community.

NICE provides authoritative guidance for appropriate treatment and care of patients within the National Health Service in England and Wales. Its resources are widely referred to by clinicians around the world, including Singapore.

The guide is expected to be a helpful tool for primary care health workers, as doctors, clinics and hospitals embrace telemedicine during the pandemic.

In Singapore, the usage of telemedicine has picked up, with the government encouraging the use of video consultations for several chronic conditions, to promote safe distancing and to reduce the risk of transmission of the coronavirus.

Assoc Prof Car who is with NTU's Lee Kong Chian School of Medicine said, "We can expect to see an increasing shift from in-person consultation to telemedicine in the future. It is therefore important for clinicians to have clarity on good practice and our guideline addresses the urgent need by providing a broad orientation to a COVID-19 consultation, including safety net advice for patients."

Trisha Greenhalgh, who is Professor of Primary Care Health Sciences at Oxford University, said, "We've long known that telemedicine can help doctors save money and time. Yet face-to-face consultations have remained standard operating procedure and the 'go-to' option. Now, COVID-19 has dramatically altered the risk-benefit balance in video versus face-to-face consultations. Suddenly, doctors need to become confident at consulting patients via video. Our work offers evidence-based advice from an international team which we hope can provide some clarity for those in the primary care service."

The guide advises on how to conduct a 'query COVID-19' consultation remotely, how to choose between telephone and video appointments, questions to ask, considerations when arranging follow-up, and next steps. A visual summary is also included (see Notes to Editor).

For instance, the guide spells out how doctors should ask a patient to try to talk in full sentences in order to check on their respiratory function, since the inability to speak in complete sentences is common in severe illness.

It also highlights the need for doctors to look out for the general demeanour of a patient over video. Decisions and actions are also detailed, which includes instructions to arrange for immediate medical help when red flags for COVID-19 like severe shortness of breath at rest, or pain or pressure in the chest is reported by patients.

The guide was written based on a mix of COVID-19 published and unpublished research findings - the majority of which are from China and from the World Health Organization (WHO) guidance.

The team also conducted a poll of 50 medical professionals from countries including United Kingdom and Singapore, and leveraged findings from earlier related literature.

In experiments with mice, researchers have studied neuronal mechanisms and found a way to by and large prevent spasticity from developing after spinal cord injuries. A new study from the University of Copenhagen shows that the researchers have done this by using already approved medicine for high blood pressure.

Spinal cord injury can be highly debilitating and affect motor skills, the sensation as well as autonomic brain functions. Besides, the injury will often lead to the development of spasticity which manifests itself in involuntary, sustained or rhythmic muscle contractions. It is estimated that 70 percent of those who have a spinal cord injury will develop spasticity.

Now, researchers from the University of Copenhagen have discovered a possible treatment - tested on mice - against the development of spasticity following a spinal cord injury. After the treatment, the mice showed no or only modest signs of spasticity.

The researchers treated the mice with the drug nimodipine, which is an already approved drug that has been used since the 1980s.

'We show that nimodipine by and large can prevent the development of spasticity after a spinal cord injury if administered soon after the injury and for an extended period of time. One of the most surprising and interesting elements in the study is that the effect continues, even after treatment has stopped', says co-author Ole Kiehn, Professor at the Department of Neuroscience.

The new results have been published in the scientific journal Science Translational Medicine.

The Effect is Long-Lasting

Nimodipine is a drug that is used, among other things, against high blood pressure. The researchers' experiments showed that treatment with nimodipine must be started immediately after the spinal cord injury has occurred, otherwise it will not work.

In addition, the treatment must continue for an extended period of time. In the experiment, the mice were treated with the drug for six weeks and then observed for nine weeks, where they developed no or only mild signs of spasticity.

The most surprising thing to the researchers was that the effect was long-lasting.

'We had guessed that the spasticity would be blocked for as long as the pharmacological treatment was ongoing. But we were positively surprised to see that the development of spasticity remained blocked even after we stopped the pharmacological treatment', says co-author Carmelo Bellardita, Postdoc at the Department of Neuroscience.

Blocked Calcium Channel

Nimodipine works by blocking calcium channels - which belong to the group of so-called L-type calcium channels - found in many nerve cells in the spinal cord.

In the study, the researchers show that the effect of nimodipine is due to the blocking of one specific L-type calcium channel, the so-called CaV1.3 channel. By genetically removing that type of calcium channels in the spinal cord of mice, they achieved the same result: the development of spasticity was blocked.

According to the researchers, the results could potentially also be relevant to other diseases where spasticity may develop. For example, in connection with multiple sclerosis and stroke.

It is still uncertain whether nimodipine will have the same effect on human spasticity as all experiments have been done on mice. The researchers will now study this question.

'We are quite optimistic that nimodipine will have the same effect in humans. But we cannot be certain. Nimodipine is an approved drug that easily enters the brain, and we will now begin trials together with other researchers where we test nimodipine on healthy test subjects to study the effect on various reflexes and motor skills. Subsequently, it may potentially be possible to test the drug on people with spasticity', says Ole Kiehn.

PROVIDENCE, R.I. [Brown University] -- Reconstructing how many individuals first settled the many small islands in the Pacific and when they arrived remain important scientific questions, as well as an intriguing ones for understanding human history. Human migrations into the islands of Remote Oceania -- from circa 3,000 to 1,200 years ago -- mark the last major movement into locations previously uninhabited by humans.

These questions are also crucial as part of scientific efforts to understand the role of early history of Pacific islanders on contemporary public health problems including obesity and associated non-communicable diseases such as hypertension and Type 2 diabetes.

A new study in Proceedings of the National Academy of Sciences analyzed the genomes of 1,197 individuals in Samoa and found that the effective population size of the first Samoans was small -- ranging from 700 to 3,400 people during the time period from approximately 3,000 to about 1,000 years ago. Starting about 1,000 years ago, population size rapidly increase to about 10,000 individuals, coinciding with increasing agricultural and socio-political complexity, but also with previously hypothesized contacts with other Oceanic peoples.

This population history scenario for Samoa is consistent with the existing archaeological evidence of few, widely scattered and small-sized settlements in the first 2,000 years after Samoa's initial settlement. But it contrasts with archaeological population reconstructions of much larger population sizes for adjacent Pacific peoples in Tonga and Fiji during that first 1,500 to 2,000 years after initial discoveries around 3,000 years ago.

The research team's conclusions could help in understanding health conditions of particular importance to people in Samoa, home to some of the highest rates of obesity, heart disease and diabetes in the world.

"These findings are relevant for our ongoing public health research in Samoan populations because they highlight the importance of population history and size in influencing our ability to identify the effect of novel genetic variations, and their interactions with 21st century environments on population health," said Stephen McGarvey, study co-author and a professor of epidemiology and of anthropology at Brown University.

McGarvey has studied extensively obesity and diseases that stem from obesity -- including diabetes, cardiovascular disease, kidney disease and cancer -- in Samoa, which are not only a threat to individual health, but to the nations' economic and social development.

"Smaller populations and the evolutionary mechanisms resulting from them, including genetic drift from bottlenecks and natural selection from novel challenging environments such as experienced by the first settlers of Samoa, make it easier to detect new gene variants and different frequencies of known variants that affect cardiometabolic disease risk factors now in the 21th century," he said.

The new study also found that modern Samoans derive largely from the Austronesian lineage, including the aboriginal peoples of Taiwan, Island Southeast Asia, coastal New Guinea and other island groups of Oceania -- but share 24% of their ancestry with Papuans, the descendants of the people who settled Papua/New Guinea, an estimate markedly lower than found in neighboring Polynesian groups.

The researchers also found strong evidence of population reduction coincident with outside contact from European-derived groups, presumably from infectious diseases new to Samoan immune systems and societal shocks from such epidemics. The whole genome sequence data from participants' DNA also enabled findings about some genetic diversification within Samoa that may be reflective of regional and local social processes. The genomic data also showed an increase in population size about 150 years ago.

"These findings indicate that the modern Samoan population is a result of these demographic dynamics from the earliest times 3,000 years ago to the very recent colonial period in the 19th century," McGarvey said. "Any questions about putative genetic influences and their interactions with modern ways of life must be asked in the context of population history."

A new poll finds that a majority of Americans now say the federal government should actively seek to reduce inequality, amid the worsening economic crisis produced by Covid-19. A national survey from Harris Insights & Analytics of 2,018 Americans, conducted April 7-9, 2020, finds that 78% of Americans agree that "considering the spread of coronavirus in the United States and its impact on the economy and the American people," it is "somewhat" or "very important" that "the U.S. government commit to reducing economic inequality" over the next year, through "raising the minimum wage" and "taxing households making more than $250,000 a year to guarantee health care coverage to all Americans who lack access." Only 21% feel reducing inequality through these actions is "not very important" or "not at all important."

As the Harris polling data show, public attitudes on inequality reduction vary by income, age, and between renters and homeowners. Support for inequality reduction is higher among younger Americans, age 18-34 (82%), individuals earning less than $50,000 a year (82%), renters (84%), and individuals with children (81%), compared to older Americans, 65 and older (67%), individuals earning more than $100,000 a year (73%), home owners (76%), and individuals without children (77%).

Opinions remain divided on the severity of economic inequality. Fifty-seven percent of Americans agree that "in a time of growing economic instability and rising unemployment claims, the U.S. is increasingly divided between the 'haves' and 'have-nots.'" By comparison, 43% agree that "recent economic troubles are only temporary, and the economy will soon bounce back, so it makes little sense to speak of 'haves' and 'have-nots.'" Groups that are most likely to agree that the U.S. is divided include younger Americans, from 18-34 (64%), individuals earning less than $50,000 a year (61%), renters (61%), and women (60%), compared to older Americans age 65+ (51%), individuals earning more than $100,000 a year (53%), home owners (56%), and men (54%).

This survey was conducted online within the United States by The Harris Poll on behalf of Lehigh University from April 7 to 9, 2020, among 2,018 U.S. adults ages 18 and older. This online survey is not based on a probability sample and therefore no estimate of theoretical sampling error can be calculated. For complete survey methodology, including weighting variables and subgroup sample sizes, please contact:

Dr. Anthony DiMaggio
Associate Professor, Lehigh University
Department of Political Science
Email: Ard416@lehigh.edu

A Korean research team has developed a technology to fabricate an ultrathin material for electromagnetic interference(EMI) shielding. The research team, led by Koo Chong-Min, the head of the Materials Architecturing Research Center at the Korea Institute of Science and Technology (KIST, Acting President Yoon Seok-jin), announced that it had developed an ultrathin nanometer-thick film, using MXene, a new two-dimensional nanomaterial for EMI shielding. The research was jointly conducted with a team led by Professor Kim Sang-ouk of the Department of Materials Science and Engineering at Korea Advanced Institute of Science and Technology (KAIST, President: Shin Sung-chul) and a research team led by Professor Yury Gogotsi from Drexel University, USA.

Micrometer thick MXene films with high electrical conductivity, reported by Koo Chong-min in 2016, presented outstanding electromagnetic interference shielding. However, there were no technologies that could be used to directly apply MXene to highly integrated electronic devices, such as h5G communications and mobile devices.

*MXene: A 2D nano material with the same level of electrical conductivity (10,000 S/cm) as metals. Reported by a research team led by Koo Chong-Min, head of the Materials Architecturing Research Center, KIST, the higher a material's electrical conductivity, the higher its electromagnetic interference shielding performance (?Science 353, Issue 6304, pp. 1137-1140).

The KIST-KAIST-Drexel joint research team used self-assembly technique to fabricate an ultrathin MXene film with uniform atomic-scale thickness. MXene film is reported to have exceptional absolute electromagnetic shielding performance (shielding effectiveness relative to thickness and density) that is far greater than that of any other material reported to date.

By adding a volatile solution onto the surface of a diluted MXene solution, the research team was able to induce floating MXene flakes. Vertical convection, resulting from differences in surface tension, caused the self-assembly of the micron-sized MXene flakes, thereby creating a large-size ultrathin MXene film with uniform atomic-scale thickness. The research team found that MXene films layered to reach 55 nm in thickness provide 99% electromagnetic shielding efficiency. Ultrathin MXene films fabricated using the team's new technology can easily be transferred onto any substrate and layered multiple times for customized thickness, transmittance, and surface resistance.

"We used a self-assembly technique to fabricate an ultrathin Ti3C2Tx MXene film with uniform atomic-scale thickness. This technology helped to examine the electromagnetic shielding mechanism of nanometer-thick 2D nano materials and to develop an ultrathin electromagnetic shielding application technology for flexible electronics," said Koo Chong-Min, the head of the Materials Architecturing Research Center at KIST. "We believe that the ultrathin coated MXene technology can be applied to various electronic devices and be used for mass production, thereby facilitating research on the application of next-generation lightweight electromagnetic shielding and flexible and printable electronics."

Some new crop varieties are bred to be more nutritious. Others are more resilient, bred to tolerate harsher environmental conditions.

In a new study, researchers report a variety of wheat that combines enhanced nutrition with increased resilience. The researchers also tested a breeding method that could reduce costs and save time compared to traditional methods.

The newly developed wheat variety contains higher levels of a naturally occurring carbohydrate, called fructans.

"Wheat with increased fructan levels can be more climate-resilient in certain situations," says Lynn Veenstra, a researcher at Cornell University. "These situations include high salinity or cold temperatures".

Fructans are long chains of the sugar fructose. Unlike the fructose present in foods, such as high-fructose corn syrup, fructans cannot be digested by humans. This makes fructans a good source of soluble fiber.

Previous research has shown that consuming foods with higher fructan levels could also promote healthy gut bacteria.

In the US, a large portion of daily fructan intake comes from wheat products, such as bread. That makes developing high-fructan wheat important.

There's yet another advantage to using high-fructan wheat. "We wouldn't have to supplement wheat products with fructans or fiber from other sources," says Veenstra. "This wheat would already contain higher levels of fructans."

But breeding high-fructan wheat can be time-consuming and expensive. "The development of nutritionally improved wheat varieties often requires extensive resources," says Veenstra.

Typically, a process called phenotyping takes the most time. Phenotyping is the measurement of crop characteristics - like fructan levels or yield.

Phenotyping allows plant breeders to compare new and existing varieties of crops. For example, they can test if newer varieties have higher or lower fructan levels than existing crops. At the same time, they need to make sure other crop features - like yield or disease resistance - haven't been reduced.

A relatively new breeding method can expedite the development of new crop varieties. Veenstra and colleagues tested variations of this method, called genomic selection.

Genomic selection uses a relatively small 'training' set of individual plants. Researchers combine phenotyping and genetic data from this training set of plants. Then they use these data to train a statistical model.

Once trained, the statistical model can predict plant characteristics - like fructan levels - based solely on genetics.

"This allows crop breeding without needing to collect data on observed characteristics," says Veenstra.

Genomic selection saves time and resources in two ways. First, the training set of plants is relatively small. That allows phenotyping to be concluded quickly. Second, genetic testing can often be much quicker than measuring crop characteristics.

Ultimately, genomic selection can allow breeders to save both cost and time during the breeding process.

There are some caveats to using genomic selection, though. Inbreeding can happen, for instance, which can reduce crop diversity. Reduced diversity can make crops susceptible to diseases.

So Veenstra and her colleagues tested two different modes of genomic selection. They found that one method led to wheat with higher fructans while maintaining genomic diversity.

"I think this is the most important finding of this study," says Veenstra. "Genomic selection can be used for nutritional breeding."

Researchers still need to know more about the fructans in the new wheat variety. "We also want to determine how stable these fructans are during food processing," says Veenstra.

For example, yeast degrades different fructans at different rates. That would impact how much fructan ends up in a loaf of bread.

"I believe both wheat growers and consumers stand to benefit from high-fructan wheat," says Veenstra. "For wheat growers, high-fructan varieties have the potential to withstand climatic stress. For consumers, high-fructan wheat products may have positive impacts on gut-health."

As human activity shapes Earth's climate, animals must increasingly adapt to new environmental conditions. The thermoneutral zone -- the ambient temperature range in which mammals can maintain their body temperature without expending extra energy -- is a key factor in estimating a species' ability to survive in a warming world.

Reptiles and other ectotherms that rely on the environment to regulate their body temperature are believed to be more vulnerable to global warming in the tropics than in temperate climates. However, less is known about small tropical mammals, especially those active during the day.

To better understand if small tropical mammals also have increased vulnerability as their environments heat up, Danielle Levesque, University of Maine assistant professor of mammology and mammal health, and collaborators from the Universiti Malaysia Sarawak studied Bornean treeshrews. They measured the oxygen consumption of the wild-caught lesser treeshrews (Tupaia minor) over a range of temperatures, calculating the animals' resting metabolic rate and thermoneutral zone.

The team found that, like other treeshrew species, the animals exhibited more flexibility in body temperature regulation than other small mammals. This contradicts current assumptions that the upper limit of the thermoneutral zone between mammal species has little variation. The findings highlight the importance of further research on the energetics of mammals in the equatorial tropics.