Wednesday, August 31, 2022

Study finds tiny brain area controls work for rewards

The lateral habenula in the mouse brain, with axons streaming down to dopaminergic and serotonergic centers. Credit: Warden Lab

A tiny but important area in the middle of the brain acts as a switch that determines when an animal is willing to work for a reward and when it stops working, according to a study published Aug. 31 in the journal Current Biology.

“The study changes how we think about this particular brain region,” said senior author Melissa Warden, assistant professor and Miriam M. Salpeter Fellow in the Department of Neurobiology and Behavior, which is shared between the College of Arts and Sciences and the College of Agriculture and Life Sciences.

“It has implications for psychiatric disorders, particularly depression and anxiety,” Warden said.

The paper, “Tonic Activity in Lateral Habenula Neurons Acts as a Neutral Valence Brake on Reward-Seeking Behavior,” illuminates the role of the lateral habenula, a small structure on top of the thalamus, which funnels higher-level information from the front and center of the brain to areas that produce neurotransmitters such as serotonin and dopamine.

The lateral habenula’s exact role has been unclear until now. The new study shows that when neurons in this brain area turn off, an animal will work for rewards; when those neurons fire, the animal becomes disengaged and stops working. Experiments revealed that the lateral habenula turns on specifically when an animal has had enough of a reward and is satisfied, or when it finds its work no longer yields a reward.

Signs of Saturation Emerge from Particle Collisions at RHIC

Brookhaven Lab physicists Xiaoxuan Chu and Elke-Caroline Aschenauer at the STAR detector of the Relativistic Heavy Ion Collider (RHIC).
Source/Credit: Brookhaven National Laboratory

Nuclear physicists studying particle collisions at the Relativistic Heavy Ion Collider (RHIC)—a U.S. Department of Energy Office of Science user facility at DOE’s Brookhaven National Laboratory—have new evidence that particles called gluons reach a steady “saturated” state inside the speeding ions. The evidence is suppression of back-to-back pairs of particles emerging from collisions between protons and heavier ions (the nuclei of atoms), as tracked by RHIC’s STAR detector. In a paper just published in Physical Review Letters, the STAR collaboration shows that the bigger the nucleus the proton collides with, the larger the suppression in this key signature, as predicted by theoretical models of gluon saturation.

“We varied the species of the colliding ion beam because theorists predicted that this sign of saturation would be easier to observe in heavier nuclei,” explained Brookhaven Lab physicist Xiaoxuan Chu, a member of the STAR collaboration who led the analysis. “The good thing is RHIC, the world’s most flexible collider, can accelerate different species of ion beams. In our analysis, we used collisions of protons with other protons, aluminum, and gold.”

Peering Into Mirror Nuclei

Diagram showing a high-energy electron scattering from a correlated nucleon in the mirror nuclei tritium (left) and helium-3 (right). The electron exchanges a virtual photon with one of the two correlated nucleons, knocking it out of the nucleus and allowing its energetic partner to escape. Both nuclei have neutron-proton pairs, while tritium has an additional neutron pair and helium-3 has an additional proton pair.
Credit: Jenny Nuss/Berkeley Lab

The atomic nucleus is a busy place. Its constituent protons and neutrons occasionally collide, and briefly fly apart with high momentum before snapping back together like the two ends of a stretched rubber band. Using a new technique, physicists studying these energetic collisions in light nuclei found something surprising: protons collide with their fellow protons and neutrons with their fellow neutrons more often than expected.

The discovery was made by an international team of scientists that includes researchers from the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), using the Continuous Electron Beam Accelerator Facility at DOE’s Thomas Jefferson National Accelerator Facility (Jefferson Lab) in Virginia. It was reported in a paper published today in the journal Nature.

Understanding these collisions is important for interpreting data in a wide range of physics experiments studying elementary particles. It will also help physicists better understand the structure of neutron stars – collapsed cores of giant stars that are among the densest forms of matter in the universe.

John Arrington, a Berkeley Lab scientist, is one of four spokespersons for the collaboration, and Shujie Li, the lead author on the paper, is a Berkeley Lab postdoc. Both are in Berkeley Lab’s Nuclear Science Division.

"Greener" Fertilizer and Carbon-free Fuels Come Closer to Reality

Photo by Richard Bell on Unsplash

A little over 100 years ago, humankind learned how to take nitrogen from the atmosphere (where it is plentiful) and turn it into ammonia that can be used as source of fertilizer for growing food. That chemical process, known as nitrogen fixation, has allowed huge increases in crop production and a subsequent boom in human populations fed by those crops.

Nearly all artificial nitrogen fixation is done with what is known as the Haber–Bosch process, which uses a metal catalyst to combine gaseous nitrogen and hydrogen into ammonia, at high pressures and temperatures. Ammonia fixed through this process is estimated to be responsible for growing crops that feed half the world's population.

But there is another large source of nitrogen fixation: bacteria that live in soil, which fix nitrogen at normal atmospheric temperatures and pressures. In recent decades, researchers searching for sustainable agriculture practices have looked to these microbes as inspiration for developing nitrogen-fixation processes that are easier to conduct and more environmentally friendly than the energy-intensive Haber-Bosch process. Now, a team at Caltech led by Jonas Peters, Bren Professor of Chemistry and director of the Resnick Sustainability Institute, has made a breakthrough that increases the efficiency of one of these low-temperature and low-pressure processes, further opening the door to greener fertilizer, and even the production of zero-carbon fuels.

Climate change and ocean oxygen

Oxygen-deficient zones (in red) shrank during long warm periods in the past, contrary to widespread expectations.   
Image Credit: Alexandra Auderset, Princeton and MPIC

In the last 50 years, oxygen-deficient zones in the open ocean have increased. Scientists have attributed this development to rising global temperatures: Less oxygen dissolves in warmer water, and the tropical ocean’s layers can become more stratified.

But now, contrary to widespread expectations, an international team of scientists led by researchers from the Max Planck Institute for Chemistry and Princeton University has discovered that oxygen-deficient zones shrank during long warm periods in the past.

“We had not expected such a clear effect,” said Alexandra Auderset, first author of the new paper in the journal Nature and currently a visiting postdoctoral research fellow at Princeton University. She led the study with Alfredo Martínez-García at the Max Planck Institute for Chemistry in Mainz, as part of a long-term collaboration with Daniel Sigman’s group at Princeton University.

Understanding these changes is important because “when oxygen becomes scarce, life has a harder time,” said Sigman, Dusenbury Professor of Geological and Geophysical Sciences. For example, in low-oxygen regions of the eastern Pacific and northern Indian Ocean, only specialized microbes and organisms with a slow metabolism — such as jellyfish — can survive.

Marine Protected Areas in Antarctica should include young emperor penguins, scientists say

A group of Juvenile emperor penguins at Atka Bay on the sea ice edge ready for their first swim. In four years, they will return to breed, spending much of their time in unprotected areas of the Southern Ocean.
Image credit: Daniel P. Zitterbart/ ©Woods Hole Oceanographic Institution

Scientists at the Woods Hole Oceanographic Institution (WHOI) and European research institutions are calling for better protections for juvenile emperor penguins, as the U.S. Fish and Wildlife Service considers listing the species under the Endangered Species Act and the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) considers expanding the network of Marine Protected Areas (MPAs) in the Southern Ocean.

In one of the few long-term studies of juvenile emperor penguins–and the only study focused on a colony on the Weddell Sea–research published today in Royal Society Open Science found that the young birds spend about 90 percent of their time outside of current and proposed MPAs. The study, which tracked eight penguins with satellite tags over a year, also found that they commonly traveled over 1,200 kilometers (745 miles) beyond the species range defined by the International Union for Conservation of Nature (IUCN), which is based on studies of adult emperor penguins from a few other colonies.

Considered immature until about 4 years of age, juvenile emperor penguins are more vulnerable than adults because they have not fully developed foraging and predator avoidance skills. As climate change reduces sea-ice habitat and opens up new areas of the Southern Ocean to commercial fishing, the researchers conclude that greatly expanded MPAs are crucial to protect this iconic, yet threatened, penguin species at every life stage.

Brain activity during sleep differs in young people with genetic risk of psychiatric disorders

Photo by Lux Graves on Unsplash

Young people living with a genetic alteration that increases the risk of psychiatric disorders have markedly different brain activity during sleep, a study led by researchers from the Universities of Bristol and Cardiff published in the journal eLife shows.

The brain activity patterns during sleep shed light on the neurobiology behind a genetic condition called 22q11.2 Deletion Syndrome (22q11.2DS) and could be used as a biomarker to detect the onset of neuropsychiatric disorders in people with 22q11.2DS.

Caused by a gene deletion of around 30 genes on chromosome 22, 22q11.2DS occurs in one in 3000 births. It increases the risk of intellectual disability, autism spectrum disorder (ASD), attention-deficit hyperactivity disorder (ADHD) and epileptic seizures. It is also one of the largest biological risk factors for schizophrenia. However, the biological mechanisms underlying psychiatric symptoms in 22q11.2DS are unclear.

Marianne van den Bree, co-senior author and Professor of Psychological Medicine at Cardiff said: “We have recently shown that the majority of young people with 22q11.2DS have sleep problems, particularly insomnia and sleep fragmentation, that are linked with psychiatric disorders. However, our previous analysis was based on parents reporting on sleep quality of their children, and the neurophysiology – what’s happening to brain activity – has not yet been explored.”

Scientists Determined Content of Harmful Substances in Ekaterinburg Mud

In Ekaterinburg, scientists made more than 60 mud samples.
Photo credit: Ilya Safarov

Scientists at Ural Federal University and the Institute of Industrial Ecology Ural Branch of the Russian Academy of Sciences, together with their colleagues from Southern Federal University, Egypt and Saudi Arabia, have studied the concentration of potentially harmful substances in surface sediments in Ekaterinburg and identified possible sources of pollution. The research contributes to the development and adoption of standards for the content of harmful substances in mud. The results of the research, funded by the Russian Science Foundation (Project №18-77-10024), are described in the journal Chemosphere.

Over several seasons, scientists took more than 60 mud samples collected at the same sites: first, in green areas with flower beds and lawns, second, from roads and, third, from neighborhoods, parking lots and sidewalks in residential areas of the 1.5 million metropolises. Dirt samples were dried under laboratory conditions for several weeks and then passed through a 1-mm sieve. The resulting dust was analyzed.

"In samples from all surveyed areas the highest concentrations of iron and manganese are found, as they are contained in rocks and soils, on which Yekaterinburg is located. Dust from green areas, in addition, has high concentrations of zinc and lead, in samples from roads - cobalt, nickel, tin and antimony, dust from yard passages, parking lots and sidewalks is full of zinc and copper," says Andrian Seleznev, Associate Professor of Department of Health and Safety at UrFU, Senior Scientist of Industrial Ecology Ural Branch of the Russian Academy of Sciences.

Archaeology and ecology combined sketch a fuller picture of past human-nature relationships

Hunting of a deer. Wall painting, 6th millennium BC. Museum of Anatolian Civilizations, Ankara.
 Image source: Wikimedia Commons

For decades now, archaeologists wielded the tools of their trade to unearth clues about past peoples, while ecologists have sought to understand current ecosystems. But these well-established scientific disciplines tend to neglect the important question of how humans and nature interacted and shaped each other across different places and through time. An emerging field called archaeoecology can fill that knowledge gap and offer insights into how to solve today’s sustainability challenges, but first, it must be clearly defined. A new paper by SFI Complexity Fellow Stefani Crabtree and Jennifer Dunne, SFI’s Vice President for Science, lays out the first comprehensive definition of archaeoecology and calls for more research in this nascent but important field.

While an archaeology or palaeobiology study might examine a particular relationship, such as how humans in New Guinea raised cassowaries during the Late Pleistocene, archaeoecology takes a much broader view. “It’s about understanding the whole ecological context, rather than focusing on one or two species,” Dunne explains.

3D imaging contributes to a better understanding of early stages of Alzheimer's disease

Three-dimensional image of noradrenergic nerve cells in the envelope of locus coeruleus.
Photo credit: Gilvesy et al.

With the help of a new imaging technique for 3D, researchers at Karolinska Institutet, among others, have been able to characterize a part of the brain that shows the most accumulation of tau protein, an important biomarker for the development of Alzheimer's disease. The results published in the journal Acta Neuropathologica may in the future make it possible to have a more accurate neuropathological diagnosis of Alzheimer's disease spectrum at a very early stage.

Intracellular accumulation of pathological tau protein in the brain is a hallmark of several age-related neurodegenerative diseases, including Alzheimer's disease, which accounts for 60-80 percent of all dementia cases worldwide.

In a new study, researchers at Karolinska Institutet, SciLifeLab in Stockholm and several universities from Hungary, Canada, Germany and France have applied a state-of-the-art immune imaging technology, in combination with light sheet microscopy, to investigate a human brain stem core, locus coeruleus, which is an important core in the mammalian brain.

Tuesday, August 30, 2022

How Prehistoric Humans Simplified the World’s Food Webs

Illustration depicting all mammal species that would inhabit Southern California today if not for human-linked extinction. Extinct species appear in black and white.
Credit: Oscar Sanisidro/University of Alcalá

Research conducted with the help of a University at Albany anthropologist has revealed the cascading effects that humans have had on mammal declines and their food webs over the last 130,000 years, a new study in the journal Science shows.

The study, which was carried out by researchers in the United States, United Kingdom, Denmark and Spain, set out to determine the magnitude of food web loss among mammals since the Late Pleistocene, following the arrival and expansion of human populations around the world.

“We’ve known for a long time that as humans spread out of Africa, everywhere they went, waves of animal extinctions followed their arrival,” said John Rowan, an assistant professor of anthropology at UAlbany who co-authored the study. “When humans got to North America, there were saber-toothed cats, dire wolves, mammoths, mastodons and giant bears. But all these animals start to disappear soon after our species show up.”

While scientists were aware of the human link to mammal extinctions, little was understood regarding how those losses reverberated throughout food webs, which characterize how species interact with one another in an ecosystem. Extinction alone can impact the links in a food web, but so can reductions and shifts in geographic range due to human impacts, such as habitat destruction.

Scientists Grow Lead-Free Solar Material With a Built-In Switch

Light microscopy image of nanowires, 100 to 1,000 nanometers in diameter, grown from cesium germanium tribromide (CGB) on a mica substrate. The CGB nanowires are samples of a new lead-free halide perovskite solar material that is also ferroelectric.
Credit: Peidong Yang and Ye Zhang/Berkeley Lab

Solar panels, also known as photovoltaics, rely on semiconductor devices, or solar cells, to convert energy from the sun into electricity.

To generate electricity, solar cells need an electric field to separate positive charges from negative charges. To get this field, manufacturers typically dope the solar cell with chemicals so that one layer of the device bears a positive charge and another layer a negative charge. This multilayered design ensures that electrons flow from the negative side of a device to the positive side – a key factor in device stability and performance. But chemical doping and layered synthesis also add extra costly steps in solar cell manufacturing.

Now, a research team led by scientists at DOE’s Lawrence Berkeley National Laboratory (Berkeley Lab), in collaboration with UC Berkeley, has demonstrated a unique workaround that offers a simpler approach to solar cell manufacturing: A crystalline solar material with a built-in electric field – a property enabled by what scientists call “ferroelectricity.” The material was reported earlier this year in the journal Science Advances.

Researchers produce nanodiamonds capable of delivering medicinal and cosmetic remedies through the skin

Nanodiamond applied on skin samples and penetrated through all skin layers: nanodiamond concentration reduces as the layer is deeper
Credit: Prof. Dror Fixler, Bar-Ilan University 

The skin is one of the largest and most accessible organs in the human body, but penetrating its deep layers for medicinal and cosmetic treatments still eludes science.

Although there are some remedies -- such as nicotine patches to stop smoking -- administered through the skin, this method of treatment is rare since the particles that penetrate must be no larger than 100 nanometers (one thousandth of a centimeter). Creating effective tools using such tiny particles is a great challenge. Because the particles are so small and difficult to see, it is equally challenging to determine their exact location inside the body – information necessary to ensure that they reach the intended target tissue. Today such information is obtained through invasive, often painful, biopsies.

A novel approach, developed by researchers at Bar-Ilan University in Israel, provides an innovative solution to overcoming both of these challenges. Combining techniques in nanotechnology and optics, they produced tiny (nanometric) diamond particles so small that they are capable of penetrating skin to deliver medicinal and cosmetic remedies. In addition, they created a safe, laser-based optical method that quantifies nanodiamond penetration into the various layers of the skin and determines their location and concentration within body tissue in a non-invasive manner – eliminating the need for a biopsy.

X-shaped radio galaxies might form more simply than expected

When astronomers use radio telescopes to gaze into the night sky, they typically see elliptical-shaped galaxies, with twin jets blasting from either side of their central supermassive black hole. But every once in a while, — less than 10% of the time — astronomers might spot something special and rare: An X-shaped radio galaxy, with four jets extending far into space.

Although these mysterious X-shaped radio galaxies have confounded astrophysicists for two decades, a new Northwestern University study sheds new insight into how they form — and its surprisingly simple. The study also found that X-shaped radio galaxies might be more common than previously thought.

The study was published in the Astrophysical Journal Letters. It marks the first large-scale galaxy accretion simulation that tracks the galactic gas far from the supermassive black hole all the way toward it.

Simple conditions lead to messy result

Using new simulations, the Northwestern astrophysicists implemented simple conditions to model the feeding of a supermassive black hole and the organic formation of its jets and accretion disk. When the researchers ran the simulation, the simple conditions organically and unexpectedly led to the formation of an X-shaped radio galaxy.

Dolphins form largest alliance network outside humans

Male trio with female.
Credit: Dr Simon Allen

Male bottlenose dolphins form the largest known multi-level alliance network outside humans, an international team led by researchers at the University of Bristol have shown. These cooperative relationships between groups increase male access to a contested resource.

The scientists, with colleagues from the University of Zurich and University of Massachusetts, analyzed association and consortship data to model the structure of alliances between 121 adult male Indo-Pacific bottlenose dolphins at Shark Bay in Western Australia. Their findings have been published in The Proceedings of the National Academy of Sciences (PNAS).

Male dolphins in Shark Bay form first-order alliances of two-three males to cooperatively pursue consortships with individual females. Second-order alliances of four-14 unrelated males compete with other alliances over access to female dolphins and third-order alliances occur between cooperating second-order alliances.

Co-lead author Dr Stephanie King, Associate Professor from Bristol’s School of Biological Sciences explained: “Cooperation between allies is widespread in human societies and one of the hallmarks of our success. Our capacity to build strategic, cooperative relationships at multiple social levels, such as trade or military alliances both nationally and internationally, was once thought unique to our species.

“Not only have we shown that male bottlenose dolphins form the largest known multilevel alliance network outside humans, but that cooperative relationships between groups, rather than simply alliance size, allows males to spend more time with females, thereby increasing their reproductive success.”

University Created Glass with Outstanding Radiation Protection Properties

Boron-based glass is one of the best known and highest quality systems.
Photo credit: Ilya Safarov

Physicists at Ural Federal University, together with colleagues from universities in Germany, Pakistan, and Egypt, have synthesized new glass with outstanding radiation protection properties. The glass can be used in such fields as nuclear medicine, astronaut spacesuits, and spacecraft production. An article about the research was published in the Journal of Inorganic and Organometallic Polymers and Materials.

A novel boro-bariofluoride sodium calcium nickel glasses were created using a conventional melt-hardening technique. By heating the composition to melting temperature and then abruptly cooling it to room temperature, the researchers obtained a homogeneous mixture of boron oxide, barium fluoride, calcium oxide, sodium oxide, and nickel oxide.

"Research of physical and optical properties of glasses synthesized in this way showed that as nickel oxide is added to the composition, all optical characteristics of the initial boro-bariofluoride and sodium-calcium glass samples obtained from it improve. The density of glasses increases, the absorption spectrum increases, shifting towards longer wavelengths of radiation, and the ability of the system to shield photons carrying electromagnetic radiation increases," explains Ali Abouhaswa, Senior Researcher of the Section of Solid State Magnetism at UrFU, a co-author of the article.

According to the scientist, the adding of nickel oxide makes the glass applicable to optoelectronic and photoelectric devices, such as gas sensors, UV-photosensors, photovoltaic cells, photocatalysts, and electrochromic devices.

Novel Coronaviruses Are Riskiest for Spillover

A wildlife surveillance team member samples a bumblee bat for viruses in Myanmar.
Credit: Smithsonian Conservation Biology Institute

In the past decade, scientists have described hundreds of novel viruses with the potential to pass between wildlife and humans. But how can they know which are riskiest for spillover and therefore which to prioritize for further surveillance in people?

Scientists from the University of California, Davis created network-based models to prioritize novel and known viruses for their risk of zoonotic transmission, which is when infectious diseases pass between animals and humans.

Their study, published in the journal Communications Biology, provides further evidence that coronaviruses are riskiest for spillover and should continue to be prioritized for enhanced surveillance and research.

The machine learning models were designed by the EpiCenter for Disease Dynamics at the UC Davis One Health Institute in the School of Veterinary Medicine.

Prioritizing novel viruses

The models found that novel viruses from the coronavirus family are expected to have a larger number of species as hosts. This is consistent with known viruses, indicating this family of viruses should be most highly prioritized for surveillance.

‘Long COVID’ effects on business and education

Wenlong Yuan is the Stu Clark Chair in Entrepreneurship and Innovation at UM
Credit: University of Manitoba

The pandemic has affected many aspects of our lives, from health consequences to collateral damage to restaurants and “mom and pop stores.” Supply chain problems have created panic shopping among consumers and many entertainment venues have seen the number of patrons decimate.

But what about large corporations such as Wal-Mart, BMO, or Exxon? What has COVID done to them?

Wenlong Yuan is the Stu Clark Chair in Entrepreneurship and Innovation at the UM Asper School of Business. His current research includes the implications of the COVID-19 pandemic for international business strategy and small and medium-sized enterprises (SMEs).

“Every kind of firm was affected by COVID,” he says, “so on the macro level we can see a very broad impact of the pandemic. Smaller businesses were hit worse than larger companies, mostly because they had fewer employees, and they couldn’t operate when even a few were sick. But nevertheless, larger businesses felt the effects too.”

Yuan says that previous to COVID, global markets were linked to one another and increases in one sector usually meant a parallel increase in another, like oil and tech stocks varying together.

But COVID created a situation where decoupling emerged, so that the economies of traditionally linked countries began doing their own thing.

Rat lungworm transmitted by many more species than slugs, snails

Flatworm in Hawaiʻi can act as a paratenic host of rat lungworm.
Photo credit: Shinji Sugiura CC4

While many people know that rat lungworm disease can be spread to humans by slugs and snails, new research shows those creatures are not the only ones that have been transmitting the illness.

Researchers from the University of Hawaiʻi at Mānoa and the University of London, UK, combed through nearly 140 scientific studies published between 1962–2022 and found 32 species of freshwater prawns/shrimp, crayfish, crabs, flatworms, fish, sea snakes, frogs, toads, lizards, centipedes, cattle, pigs and snails can act as carriers of the rat lungworm parasite (Angiostrongylus cantonensis). Of these, at least 13 species of prawns/shrimp, crabs, flatworms, fish, frogs, toads, lizards and centipedes have been associated with causing rat lungworm disease in humans.

Robert Cowie, senior author on the study and faculty member in UH Mānoa’s School of Ocean and Earth Science and Technology (SOEST), supervised Helena Turck, first author and graduate student at the University of London, UK, who did this study as her master’s degree thesis research, remotely during the pandemic. Professor Mark Fox of the Royal Veterinary College also collaborated on the study.

Cowie explained that the rat lungworm has a complex life cycle that involves slugs and snails as so-called “intermediate” hosts and rats as “definitive” hosts in which the worms reach maturity and reproduce. Rats become infected when they eat an infected snail or slug. People also become infected when they eat an infected snail or slug, and this can lead to serious illness and occasionally death.

Sensor-based early detection of age-related diseases from home

Exemplary apartment, highlighting the sensor system used in the study. Individual rooms are equipped with motion sensors, entrance and fridge doors are equipped with magnetic door sensors, and a bed sensor is placed beneath the mattress.
Credit: NeuroTec/Nature Scientific Reports, Creative Commons License

Researchers at the University of Bern and Inselspital, Bern University Hospital have demonstrated how sensors that record movement patterns could help detect health problems in the elderly, including old-age depression, risk of falls or cognitive impairment, at an early stage. In the future, this could help seniors to live a self-determined life at home for longer and relieve increasing pressure on the healthcare system.

Specific changes in our movement patterns can be indicators of several health problems: For instance, decrease in strength often correlates with risk of falls, mild cognitive impairment, depression, sleep problems, respiratory problems, cardiac arrhythmias and increasing myocardial weakness or worsening of a COVID-19 infection. In older individuals, systematic detection of such changes could help identify chronic diseases such as dementia, Parkinson's disease, or heart disease at an early stage. These age-related health problems are often discovered late, and their progression is usually difficult to assess objectively.

Treat hepatitis E virus better after transplantation

The joint partners of the HepEDiaSeq project (from left): André Gömer (RUB); Prof. Dr. Heiner Wedemeyer (MHH); Dr. Patrick Behrendt (MHH); Dr. Christina Hecker (Kairos GmbH); Timothy Göhring (Kairos GmbH); Prof. Dr. Tanja Vollmer (HDZ); Prof. Dr. Eike Steinmann (RUB); Birgit Drawe (HDZ); Dr. Daniel Todt (RUB).
Credit: Department of Molecular and Medical Virology

A precise analysis procedure is intended to enable decision aids for the treatment of hepatitis E infection.

Hundreds of thousands of people are infected with the hepatitis E virus (HEV) in Germany every year; most don't notice it. With a weakened immune system, the disease can become dangerous, even after an organ transplant. Treating the disease more successfully in this case is the goal of the “HepEDiaSeq” project, which is coordinated by Prof. Dr. Eike Steinmann, head of the Molecular and Medical Virology Department at RUB, has started. The project team develops a procedure to recognize viral variants and thus give decision aids for the therapy. The project is funded by the Federal Ministry of Education and Research for around 1.5 million euros for three years.

In addition to Prof. Dr. Eike Steinmann private lecturer Dr. Tanja Vollmer from the Institute for Laboratory and Transfusion Medicine at the Heart and Diabetes Center North Rhine-Westphalia - University Clinic of the RUB, Prof. Dr. Heiner Wedemeyer from the Clinic for Gastroenterology, Hepatology and Endocrinology at the Hannover Medical School and private lecturer Dr. Christian Stephan from KAIROS GmbH. The scientists hope to develop a reliable method that diagnoses HEV infections highly sensitively and at the same time identifies viral variants through an interdisciplinary approach that combines specialist knowledge from medicine, virology and computer science. In order to record the enormous amounts of data from the various locations in a structured manner and to use them for in-depth analysis, the biomedical research portal CentraXX of KAIROS GmbH will be used as part of the study management.

Widespread, rarely recognized

In pregnant women or people with weakened immune systems, the infection with HEV can be chronic and at worst fatal. "This makes hepatitis E a serious problem for organ transplant people whose immune systems have to be suppressed with medication so that the foreign organ is not rejected," explains Eike Steinmann.

In the project, the partners want to develop a so-called depth sequencing process, which not only detects HEV in a highly sensitive manner, but also recognizes different variants of the virus in parallel. This should make it possible to treat the infection better. "We currently only have the active ingredient ribavirin available for the treatment," says Steinmann. “But the decision about the administration and dosage is difficult. Here we want to develop a so-called decision support tool that enables a personalized treatment approach and thus supports the therapy decisions of the treating doctors.

Source/Credit: Ruhr University Bochum


Wednesday, August 24, 2022

An extrasolar world covered in water?

Artistic rendition of the exoplanet TOI-1452 b, a small planet that may be entirely covered in a deep ocean.
Credit: Benoit Gougeon, Université de Montréal.

An international team of researchers led by Charles Cadieux, a Ph.D. student at the Université de Montréal and member of the Institute for Research on Exoplanets (iREx), has announced the discovery of TOI-1452 b, an exoplanet orbiting one of two small stars in a binary system located in the Draco constellation about 100 light-years from Earth.

The exoplanet is slightly greater in size and mass than Earth and is located at a distance from its star where its temperature would be neither too hot nor too cold for liquid water to exist on its surface. The astronomers believe it could be an “ocean planet,” a planet completely covered by a thick layer of water, similar to some of Jupiter’s and Saturn’s moons.

In an article published in The Astronomical Journal, Cadieux and his team describe the observations that elucidated the nature and characteristics of this unique exoplanet.

“I’m extremely proud of this discovery because it shows the high caliber of our researchers and instrumentation,” said René Doyon, Université de Montréal Professor and Director of iREx and of the Observatoire du Mont-Mégantic (OMM). “It is thanks to the OMM, a special instrument designed in our labs called SPIRou, and an innovative analytic method developed by our research team that we were able to detect this one-of-a-kind exoplanet.”

Researchers reveal origin of ultrafast mystery signals in valleytronic materials

 By exciting the transitional metal dichalcogenide monolayers — atomically thin semiconductors — with ultrashort pump pulses, atoms can coherently vibrate and modulate optical responses. The probe pulses can detect ultrafast modulation that shows peculiar high-frequency overtones of K-point acoustic phonons
Credit: Yokohama National University.

Tiny materials hold big mysteries, the solutions to which could bring about next-generation electronics. An international collaboration led by researchers based in Japan has solved the whodunit of cryptic overtone signals in an analysis of molybdenum diselenide, an atomically thin crystal lattice with desirable properties unique from its bulkier three-dimensional form.

They published their results in Nature Communications.

The compound belongs to a family of similarly two-dimensional semiconductors called transitional metal dichalcogenide (TMD) monolayers, all of which have electronic band structures containing so-called valleys. TMD lattices are organized as hexagons, with the corresponding wavevector, known as k-space, along the side. The side center point of the k-space is known as the “M point” and the six corners as “K (-K) points.” The valleys are the dips and rises of the electronic band at the corners of the hexagons, where energy or information-carrying particles can move to tip the material to action. The intervalley activities, especially as related to electron scattering, have remained elusive, though. In this process, phonons, or units of energy manifested as vibrations, cause the electrons to disperse and transition states in the intervalley space at ultrafast speed.

30-million-year-old amphibious beaver fossil is oldest ever found

A comparison of anklebones from the giant beaver and the newly identified species, Microtheriomys articulaquaticus, at the same scale.
Credit: Jonathan Calede / Ohio State University

A new analysis of a beaver anklebone fossil found in Montana suggests the evolution of semi-aquatic beavers may have occurred at least 7 million years earlier than previously thought, and happened in North America rather than Eurasia.

In the study, Ohio State University evolutionary biologist Jonathan Calede describes the find as the oldest known amphibious beaver in the world and the oldest amphibious rodent in North America. He named the newly discovered species Microtheriomys articulaquaticus.

Calede’s findings resulted from comparing measurements of the new species’ anklebone to about 340 other rodent specimens to categorize how it moved around in its environment – which indicated this animal was a swimmer. The Montana-based bone was determined to be 30 million years old – the oldest previously identified semi-aquatic beaver lived in France 23 million years ago.

"Beavers and other rodents can tell us a lot about mammalian evolution," said Calede, an assistant professor of evolution, ecology and organismal biology at Ohio State’s Marion campus.

Study of Ancient Skulls Sheds Light on Human Interbreeding With Neandertals

Homo neanderthalensis adult male. Reconstruction based on Shanidar 1 by John Gurche for the Human Origins Program, NMNH.
Photo Credit: Chip Clark.

Research has established that there are traces of Neandertal DNA in the genome of modern humans. Now an exploratory study that assessed the facial structure of prehistoric skulls is offering new insights, and supports the hypothesis that much of this interbreeding took place in the Near East – the region ranging from North Africa to Iraq.

“Ancient DNA caused a revolution in how we think about human evolution,” says Steven Churchill, co-author of the study and a professor of evolutionary anthropology at Duke University. “We often think of evolution as branches on a tree, and researchers have spent a lot of time trying to trace back the path that led to us, Homo sapiens. But we’re now beginning to understand that it isn’t a tree – it’s more like a series of streams that converge and diverge at multiple points.”

“Our work here gives us a deeper understanding of where those streams came together,” says Ann Ross, corresponding author of the study and a professor of biological sciences at North Carolina State University.

“The picture is really complicated,” Churchill says. “We know there was interbreeding. Modern Asian populations seem to have more Neandertal DNA than modern European populations, which is weird – because Neandertals lived in what is now Europe. That has suggested that Neandertals interbred with what are now modern humans as our prehistoric ancestors left Africa, but before spreading to Asia. Our goal with this study was to see what additional light we could shed on this by assessing the facial structure of prehistoric humans and Neandertals.”

Scientists Calculate What Could Throw El Niño Out of Balance

Abnormal temperature spikes can also lead to unpredictable results during the El Niño period, Dmitry Aleksandrov believes.
Photo credit: Ilya Safarov

Wind, humidity, temperature, ocean currents, and other parameters can lead to unpredictable El Niño results. It is a phenomenon in which the temperature of the upper Pacific Ocean rises and the near-surface waters shift eastward. The onset of El Niño affects precipitation, fisheries in Peru, Chile, Ecuador, and changes in the planet's climate. How external factors determine the behavior of atmospheric-oceanic processes in the Pacific region was calculated by UrFU physicists. They published a description of the features of the unusual phenomenon and its scenarios in the journal Physica D: Nonlinear Phenomena.

"We used the classic Vallis model, which describes El Niño. This is a simple model, it takes into account the temperature difference between the east and west coasts, the heat exchange between the Pacific Ocean and the atmosphere, and the speed of air masses movement. We also took into account external noise - parameters that also affect atmospheric and oceanic processes, such as pressure changes, humidity, wind gusts, and ocean currents," says Dmitry Aleksandrov, Head of the Ural Federal University's Laboratory of Multi-Scale Mathematical Modeling.

According to UrFU physicists' calculations, external factors have a serious influence on this phenomenon. For example, the stronger the wind, the greater the temperature amplitude. Moreover, this can throw the system out of balance and cause unpredictable weather conditions.

Tuesday, August 23, 2022

Sleepless and selfish: Lack of sleep makes us less generous

The new study shows how sleep loss dramatically reduces the desire to help others, triggered by a breakdown in the activity of key prosocial brain networks.
Image credit: Eti Ben Simon and Matthew Walker, UC Berkeley

Humans help each other — it’s one of the foundations of civilized society. But a new study by scientists at the University of California, Berkeley, reveals that a lack of sleep blunts this fundamental human attribute, with real-world consequences.

Lack of sleep is known to be associated with an increased risk of cardiovascular disease, depression, diabetes, hypertension and overall mortality. However, these new discoveries show that a lack of sleep also impairs our basic social conscience, making us withdraw our desire and willingness to help other people.

In one portion of the new study, the scientists showed that charitable giving in the week after the beginning of Daylight-Saving Time, when residents of most states “spring forward” and lose one hour of their day, dropped by 10% — a decrease not seen in states that do not change their clocks or when states return to standard time in the fall.

The study, led by UC Berkeley research scientist Eti Ben Simon and Matthew Walker, a UC Berkeley professor of psychology, adds to a growing body of evidence demonstrating that inadequate sleep not only harms the mental and physical well-being of an individual, but also compromises the bonds between individuals — and even the altruistic sentiment of an entire nation.

Study finds that ocean cooling over millennia led to larger fish

Dahiana Arcila in Reykjavík, Iceland. Arcila is the recipient of a National Science Foundation CAREER award to study the evolutionary history of marine fish.
Source: University of Oklahoma

Earth’s geological history is characterized by many dynamic climate shifts that are often associated with large changes in temperature. These environmental shifts can lead to trait changes, such as body size, that can be directly observed using the fossil record.

To investigate whether temperature shifts that occurred before direct measurements were recorded, called paleoclimatology, are correlated with body size changes, several members of the University of Oklahoma’s Fish Evolution Lab decided to test their hypothesis using tetraodontiform fishes as a model group. Tetradontiform fishes are primarily tropical marine fishes, and include pufferfish, boxfishes and filefish.

The study was led by Dahiana Arcila, assistant professor of biology and assistant curator at the Sam Noble Oklahoma Museum of Natural History, with Ricardo Betancur, assistant professor of biology, along with biology graduate student Emily Troyer, and involved collaborators from the Smithsonian Institution, University of Chicago and George Washington University in the United States, as well as the University of Turin in Italy, University of Lyon in France and CSIRO Australia.

The researchers discovered that the body sizes of these fishes have grown larger over the past hundred million years in conjunction with the gradual cooling of ocean temperatures.

How new motion-sensing technology may help standardize back-pain care

William S. Marras Professor Neurological Surgery, Orthopedics, Physical Medicine and Rehabilitation
 Credit/Source: Ohio State University

Digital health systems can tell clinicians when someone’s heart-disease risk calls for a drug to lower cholesterol or whether insulin shots are warranted for a person with type 2 diabetes.

But for millions of low-back pain sufferers, care decisions rely heavily on subjective measures of patient discomfort – often leading to expensive tests and treatments (back pain is the third-highest U.S. health care expenditure, after diabetes and heart disease) that don’t necessarily offer a permanent solution.

Ohio State University engineering and medical researchers are developing a digital health system approach designed to enhance back-pain clinical decision-making. After completing a series of studies testing precise, objective measurements they’ve perfected in the lab, the team aims to apply the data-driven practices to the assessment and repair of back problems brought on by dysfunction in the spine.

In a recent study published in Clinical Biomechanics, researchers combined self-reported pain and disability measures with data from a wearable motion-sensing system to evaluate low-back function in lumbar fusion surgery patients. While post-operative pain relief and lower disability were self-reported within six weeks, the objective metrics didn’t detect actual functional improvement in the spine for at least six months after surgery.

Researchers complete first comprehensive threat assessment of all U.S. trees

 Saplings of Endangered Q. Oglethorpensis at The Morton Arboretum
Credit: The Morton Arboretum

For the first time, researchers have completed threat assessments for all 881 native tree species in the contiguous United States, resulting in a comprehensive checklist and synthesis that will serve as a critical baseline to guide future tree conservation efforts.

The new assessment of U.S. trees reveals that 11-16% of tree species in the contiguous 48 U.S. states are threatened with extinction, with the most common threat being invasive and problematic pests and diseases. According to Abby Meyer, executive director of Botanic Gardens Conservation International-U.S. (BGCI-US), a partner on the project, “These results lay the groundwork for U.S. tree and ecosystem conservation efforts that will contribute to achieving critical international conservation goals, including the United Nations Decade for Ecosystem Restoration and the Global Tree Assessment.”

Murphy Westwood, Ph.D., vice president of science and conservation at The Morton Arboretum and senior author of the report, noted that much of the world’s biodiversity depends on trees, which offer food and habitat for countless plant, animal and fungal species while providing invaluable benefits to humans. “Understanding the current state of trees within the U.S. is imperative to protecting those species, their habitats and the countless communities they support,” she said.

Faster Fish Tracking Through the Cloud

Researchers at Pacific Northwest National Laboratory developed a receiver that can transmit near-real-time information on fish tracking to inform decisions about dam operations that support fish passage. 
 Credit: Composite photo by Cortland Johnson | Pacific Northwest National Laboratory

The fastest way to track a fish is to use the cloud, figuratively speaking. A new acoustic receiver developed by researchers at Pacific Northwest National Laboratory (PNNL) and published in the journal IEEE Internet of Things, sends near-real-time fish tracking data to the digital cloud, providing timely information to dam operators and decision-makers about when, where, and how many fish are expected to pass through dams. Instead of relying on seasonal estimates of fish migration from previous years, these data from tagged fish support more informed decisions about dam operations that affect fish passage.

“This receiver provides up-to-the-hour data to dam operators to assist in making informed day-to-day decisions in support of fish passage, like adjusting water flow when it’s clear that a large group of juvenile fish are approaching the dam,” said Jayson Martinez, a PNNL mechanical engineer who co-developed the receiver.

Hydropower dams are an important source of dependable renewable energy, generating about six percent of total electricity in the United States. Helping fish navigate them safely is a key part of reducing dams’ environmental impact. The new receiver is a critical piece of the puzzle in the ongoing endeavor to improve fish passage.

Unearthing the secrets of plant health, carbon storage with rhizosphere-on-a-chip

Scientists at ORNL have created a rhizosphere-on-a-chip research platform, a miniaturized environment to study the ecosystem around poplar tree roots for insights into plant health and soil carbon sequestration.
Credit: Carlos Jones/ORNL, U.S. Dept. of Energy

Scientists at the Department of Energy’s Oak Ridge National Laboratory have created a miniaturized environment to study the ecosystem around poplar tree roots for insights into plant health and soil carbon sequestration.

The rhizosphere-on-a-chip platform builds on the lab’s history of constructing lab-on-a-chip devices, in which tiny channels and chambers are etched on a microscope slide so that fluids can be introduced and studied for biochemical separations research and testing.

In this case scientists are mimicking soil on the chip, sprouting poplar trees in the fluid and studying the environment around their roots, known as the rhizosphere. Scientists observe how microbes interact with chemicals within the artificial soil to influence plant health and gain a better understanding of the processes governing carbon storage.

The rhizosphere is one of the most complex systems in the world, in which plant roots take up water and nutrients, create a unique physical and biogeochemical environment for microbes, and emit atmospheric carbon into the soil. There may be hundreds of different bacteria that are growing near plant roots or are influenced by the rhizosphere. ORNL researchers are particularly interested in how microbes like bacteria and fungi interact with plant roots to help plants grow faster and survive threats like drought, wildfire, disease and pests.

Reduce alcohol consumption by exercising

Photo Credit: KoolShooters
Researchers at Karolinska Institutet present new findings on reduced alcohol consumption through exercise. The three related publications, published in Drug and Alcohol Dependence, present results from the randomized controlled trial, FitForChange.

Alcohol consumption is the seventh leading risk factor for both deaths and functionally adjusted years of life globally - this new study can help improve global public health by broadening the range of effective non-stigmatizing treatments available to people with alcohol abuse.

Common barriers to seeking help

Most people with alcohol abuse never seek or receive treatment despite negative consequences for both mental and physical health. According to the researchers, perceived stigma and dissatisfaction with available treatments are common barriers to seeking help. Therefore, more effective and non-stigmatizing treatments for alcohol abuse are needed.

Current treatments include psychological therapies and medication. These are effective, but relapse rates remain high, and these treatments do not directly address the somatic health problems commonly seen in those with AUD. To address this, we invested the effects on alcohol consumption of aerobic exercise - which is recommended for general health - and yoga, an increasingly popular form of exercise which may be suitable for people with AUD, says Mats Hallgren, Project Manager, Department of Global Public Health.

No Fib: NIST Unmasks a Superfast Process for Nanoscale Machining

NIST researchers have demonstrated that a focused ion beam (FIB) can fabricate microscopic devices with fine resolution and without sacrificing high speed. Left: The conventional FIB process requires a narrow, low-current ion beam to fabricate a miniature version of a lighthouse lens in silica glass with fine resolution. Because the beam has a low current of ions, the method is time consuming. Right: Placing a protective layer of chromium oxide over the silica glass enables machinists to use a much higher-current ion beam, allowing them to fabricate the same lenses 75 times faster. 
Credit: Andrew C. Madison, Samuel M. Stavis/NIST

Cutting intricate patterns as small as several billionths of a meter deep and wide, the focused ion beam (FIB) is an essential tool for deconstructing and imaging tiny industrial parts to ensure they were fabricated correctly. When a beam of ions, typically of the heavy metal gallium, bombards the material to be machined, the ions eject atoms from the surface—a process known as milling—to sculpt the workpiece.

Beyond its traditional uses in the semiconductor industry, the FIB has also become a critical tool for fabricating prototypes of complex three-dimensional devices, ranging from lenses that focus light to conduits that channel fluid. Researchers also use the FIB to dissect biological and material samples to image their internal structure.

Machine learning algorithm predicts how to get the most out of electric vehicle batteries

Credit: (Joenomias) Menno de Jong from Pixabay 

The researchers, from the University of Cambridge, say their algorithm could help drivers, manufacturers and businesses get the most out of the batteries that power electric vehicles by suggesting routes and driving patterns that minimize battery degradation and charging times.

The team developed a non-invasive way to probe batteries and get a holistic view of battery health. These results were then fed into a machine learning algorithm that can predict how different driving patterns will affect the future health of the battery.

"This method could unlock value in so many parts of the supply chain, whether you’re a manufacturer, an end user, or a recycler, because it allows us to capture the health of the battery beyond a single number"
Alpha Lee

If developed commercially, the algorithm could be used to recommend routes that get drivers from point to point in the shortest time without degrading the battery, for example, or recommend the fastest way to charge the battery without causing it to degrade. The results are reported in the journal Nature Communications.

The health of a battery, whether it’s in a smartphone or a car, is far more complex than a single number on a screen. “Battery health, like human health, is a multi-dimensional thing, and it can degrade in lots of different ways,” said first author Penelope Jones, from Cambridge’s Cavendish Laboratory. “Most methods of monitoring battery health assume that a battery is always used in the same way. But that’s not how we use batteries in real life. If I’m streaming a TV show on my phone, it’s going to run down the battery a whole lot faster than if I’m using it for messaging. It’s the same with electric cars – how you drive will affect how the battery degrades.”

Revealed missing step in lipid formation could enable detection of past climate

A team from Penn State and the University of Illinois Urbana-Champaign has determined the missing step in the formation of a molecule called GDGT, which is a promising candidate for use as an indicator of past climate. The team determined the X-ray crystal structure of an enzyme that facilitates this process called GDGT/MAS—shown here bound to additional cofactors.
Credit: Booker Lab | Pennsylvania State University

The missing step in the formation of a lipid molecule that allows certain single-celled organisms to survive the most extreme environments on Earth has now been deciphered. This new understanding, uncovered by a team of biochemists from Penn State and the University of Illinois Urbana-Champaign, could improve the ability of the lipids to be used as an indicator of temperature across geological time.

The lipid, called glycerol dibiphytanyl glycerol tetraether (GDGT), is found in the cell membrane of some species of archaea, single-celled organisms that were originally thought to be bacteria but now are considered a separate group. This lipid provides the stability for some species to thrive in environments with extremely high temperatures, salinity or acidity, like thermal vents in the ocean, hot springs and hypersaline waters. The unique stability of GDGT also allows it to be detected hundreds or even thousands of years after the organism dies. Because these organisms tend to produce more GDGT at higher temperatures, it is considered a promising candidate for estimating temperature over geologic time.

“For GDGT to be accurately used as a proxy to reconstruct changes in geological temperatures, scientists need to better understand how it is made, what genes code for it, and which species can create it,” said Squire Booker, a biochemist at Penn State, an investigator with the Howard Hughes Medical Institute, and leader of the research team. “But, until now, there has been a missing step in the formation of this lipid. We used imaging techniques coupled with chemical and biochemical methods to deconstruct the chemical pathway for this missing step.”

COVID-19 pandemic fallout worse for women

Dr Terry Fitzsimmons, Lead author
Credit: University of Queensland

Researchers from The University of Queensland have found the COVID-19 pandemic in Australia has had a greater financial and psychological impact on women than men.

A study conducted by the UQ Business School shows women have experienced more significant impacts on their overall employment, hours of work, domestic labor and mental health and wellbeing.

Lead researcher Dr Terry Fitzsimmons said one reason was the over-representation of women in industries most affected by lockdowns.

“Women are also more likely to be casual, part-time or contract workers which were among the first to lose their jobs as businesses struggled in response to lockdown,” Dr Fitzsimmons said.

Additionally, the study found women were less likely to be considered ‘essential workers’, so bore a greater share of caring responsibilities including home schooling, when schools and child care centers closed.

“Women either reduced their work hours or stopped working altogether and took on more domestic labor than their male counterparts while at home with their children,” Dr Fitzsimmons said.

Researchers develop the first AI-based method for dating archaeological remains

Credit: Unsplash

By analyzing DNA with the help of artificial intelligence (AI), an international research team led by Lund University in Sweden has developed a method that can accurately date up to ten-thousand-year-old human remains.

Accurately dating ancient humans is key when mapping how people migrated during world history.

The standard dating method since the 1950s has been radiocarbon dating. The method, which is based on the ratio between two different carbon isotopes, has revolutionized archaeology. However, technology is not always completely reliable in terms of accuracy, making it complicated to map ancient people, how they moved and how they are related.

In a new study published in Cell Reports Methods, a research team has developed a dating method that could be of great interest to archaeologists and paleognomicists.

“Unreliable dating is a major problem, resulting in vague and contradictory results. Our method uses artificial intelligence to date genomes via their DNA with great accuracy, says Eran Elhaik, researcher in molecular cell biology at Lund University.

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