Friday, May 20, 2022

Neuromorphic Memory Device Simulates Neurons and Synapses​

A neuromorphic memory device consisting of bottom volatile and top nonvolatile memory layers emulating neuronal and synaptic properties, respectively
Credit: KAIST

Researchers have reported a nano-sized neuromorphic memory device that emulates neurons and synapses simultaneously in a unit cell, another step toward completing the goal of neuromorphic computing designed to rigorously mimic the human brain with semiconductor devices.

Neuromorphic computing aims to realize artificial intelligence (AI) by mimicking the mechanisms of neurons and synapses that make up the human brain. Inspired by the cognitive functions of the human brain that current computers cannot provide, neuromorphic devices have been widely investigated. However, current Complementary Metal-Oxide Semiconductor (CMOS)-based neuromorphic circuits simply connect artificial neurons and synapses without synergistic interactions, and the concomitant implementation of neurons and synapses still remains a challenge. To address these issues, a research team led by Professor Keon Jae Lee from the Department of Materials Science and Engineering implemented the biological working mechanisms of humans by introducing the neuron-synapse interactions in a single memory cell, rather than the conventional approach of electrically connecting artificial neuronal and synaptic devices.

Neuroscientists Find Brain Mechanism Tied to Age-Related Memory Loss

As the brain ages, a region in the hippocampus becomes imbalanced, causing forgetfulness. Scientists say understanding this region of the brain and its function may be the key to preventing cognitive decline.

Working with rats, neuroscientists at Johns Hopkins University have pinpointed a mechanism in the brain responsible for a common type of age-related memory loss. The work, published in Current Biology, sheds light on the workings of aging brains and may deepen our understanding of Alzheimer's disease and similar disorders in humans.

"We're trying to understand normal memory and why a part of the brain called the hippocampus is so critical for normal memory," said senior author James Knierim, a professor at the university's Zanvyl Krieger Mind/Brain Institute. "But also with many memory disorders, something is going wrong with this area."

Neuroscientists know that neurons in the hippocampus, located deep in the brain's temporal lobe, are responsible for a complementary pair of memory functions called pattern separation and pattern completion. These functions occur in a gradient across a tiny region of the hippocampus called CA3.

In normal brains, pattern separation and pattern completion work hand-in-hand to sort and make sense of perceptions and experiences, from the most basic to the highly complex. If you visit a restaurant with your family and a month later you visit the same restaurant with friends, you should be able to recognize that it was the same restaurant, even though some details have changed—this is pattern completion. But you also need to remember which conversation happened when, so you do not confuse the two experiences—this is pattern separation.

Superconductivity and charge density waves caught intertwining at the nanoscale

Artist's rendering of an infrared laser quenching charge density waves.
Credit: Greg Stewart/SLAC National Accelerator Laboratory

Room-temperature superconductors could transform everything from electrical grids to particle accelerators to computers – but before they can be realized, researchers need to better understand how existing high-temperature superconductors work.

Now, researchers from the Department of Energy's SLAC National Accelerator Laboratory, the University of British Columbia, Yale University and others have taken a step in that direction by studying the fast dynamics of a material called yttrium barium copper oxide, or YBCO.

The team reports May 20 in Science that YBCO's superconductivity is intertwined in unexpected ways with another phenomenon known as charge density waves (CDWs), or ripples in the density of electrons in the material. As the researchers expected, CDWs get stronger when they turned off YBCO's superconductivity. However, they were surprised to find the CDWs also suddenly became more spatially organized, suggesting superconductivity somehow fundamentally shapes the form of the CDWs at the nanoscale.

Boomerang’ effect in droplets could help clean sensitive surfaces

 A water-alcohol-propylene glycol droplet expands and then contracts, an effect that could be used to help remove particles from sensitive surfaces such as microchips.
Credit: Cornell University College of Engineering

While brooms and sponges are the means of choice to fight contamination in everyday life, cleaning sensitive surfaces such as electronic components require different tools, including evaporation-based methods that often leave behind small particles on the surface.

Through their work on the dynamics of liquid mixtures, scientists at Cornell’s Meinig School of Biomedical Engineering and the Max Planck Institute for Dynamics and Self-Organization have developed a new approach to the problem. The method uses liquid droplets that first spread out on surfaces and then contract again on their own – a boomerang effect that leaves virtually no traces when the droplets contract, unlike conventional drying, opening up new possibilities for cleaning and removing particles from sensitive surfaces such as microchips.

New study reveals the global impact of debris on marine life

Dr Sarah Gall
Credit: University of Plymouth

Nearly 700 species of marine animal have been recorded as having encountered man-made debris such as plastic and glass, according to the most comprehensive impact study in more than a decade.

Researchers at Plymouth University found evidence of 44,000 animals and organisms becoming entangled in, or swallowing debris, from reports recorded from across the globe.

Plastic accounted for nearly 92 per cent of cases, and 17 per cent of all species involved were found to be threatened or near threatened on the IUCN Red List, including the Hawaiian monk seal, the loggerhead turtle and sooty shearwater.

In a paper, 'The impact of debris on marine life', published in Marine Pollution Bulletin, authors Sarah Gall and Professor Richard Thompson present evidence collated from a wide variety of sources on instances of entanglement, ingestion, physical damage to ecosystems, and rafting, where species are transported by debris.

The missing piece to faster, cheaper and more accurate 3D mapping

The authors: Davide A. Cucci, Aurélien Brun and Jan Skaloud.
Credit: Alain Herzog/EPFL

Engineers at EPFL and the University of Geneva believe they hold the key to automated drone mapping. By combining artificial intelligence with a new algorithm, their method promises to considerably reduce the time and resources needed to accurately scan complex landscapes. It is described in a paper published in ISPRS Journal of Photogrammetry and Remote Sensing.

Three-dimensional (3D) mapping is a very useful tool for monitoring construction sites, tracking the effects of climate change on ecosystems and verifying the safety of roads and bridges. However, the technology currently used to automate the mapping process is limited, making it a long and costly endeavor.

“Switzerland is currently mapping its entire landscape using airborne laser scanners – the first time since 2000. But the process will take four to five years since the scanners have to fly at an altitude below one kilometer if they are to collect data with sufficient detail and accuracy,” says Jan Skaloud, a senior scientist at the Geodetic Engineering Laboratory (Topo) within EPFL's School of Architecture, Civil and Environmental Engineering (ENAC).

Artificial intelligence predicts patients’ race from their medical images

Researchers demonstrated that medical AI systems can easily learn to recognize racial identity in medical images, and that this capability is extremely difficult to isolate or mitigate.
 Credit: Massachusetts Institute of Technology

The miseducation of algorithms is a critical problem; when artificial intelligence mirrors unconscious thoughts, racism, and biases of the humans who generated these algorithms, it can lead to serious harm. Computer programs, for example, have wrongly flagged Black defendants as twice as likely to reoffend as someone who’s white. When an AI used cost as a proxy for health needs, it falsely named Black patients as healthier than equally sick white ones, as less money was spent on them. Even AI used to write a play relied on using harmful stereotypes for casting.

Removing sensitive features from the data seems like a viable tweak. But what happens when it’s not enough?

New breathable gas sensors may improve monitoring of health, environment

Huanyu “Larry” Cheng, assistant professor of engineering science and mechanics at Penn State, newly developed flexible, porous and highly sensitive nitrogen dioxide sensors that can be applied to skin and clothing.
Credit: Penn State/Kate Myers

Newly developed flexible, porous and highly sensitive nitrogen dioxide sensors that can be applied to skin and clothing have potential applications in health care, environmental health monitoring and military use, according to researchers.

Led by Huanyu “Larry” Cheng, assistant professor of engineering science and mechanics at Penn State, the researchers published their sensor designs, which build on previous models, and results in ACS Applied Materials and Interfaces.

The sensors monitor nitrogen dioxide, either from breath if attached under the nose, or from perspiration, if attached elsewhere on the body. Unlike taking blood samples, the direct skin attachment allows for continuous, long-term monitoring of the gas.

Cheng explained that while similar sensors exist, a key differentiator of the new design is breathability.

“The commonly used substrate materials for gas sensors are flexible, but not porous,” he said. “The accumulation of water moisture from the skin surface can potentially lead to irritation or damage to the skin surface. We need to make sure the device can be porous so that moisture can go through the sensor without accumulation on the surface.”

Thursday, May 19, 2022

Bird Flu: How It’s Spreading and What to Know About This Outbreak

A feeding frenzy of western sandpipers during the mass migration via Cordova, Alaska, a key study site in the paper.
Credit: Wendy Puryear

When it comes to avian influenza, more commonly known as bird flu, all birds are not created equal.

“The scientific community has become accustomed to speaking about influenza viruses in birds as a group, but birds are an incredibly diverse taxa of animals with different natural history, physiology, and anatomy,” says Jonathan Runstadler, professor and chair of the Department of Infectious Disease & Global Health at Cummings School of Veterinary Medicine.

Runstadler is one of the authors of a new study, published today in the journal PLOS Pathogens, which takes a data-driven look at influenza viruses circulating among different groups of birds and characterizes which types of birds are involved in spreading the virus. The timing of this paper is impeccable, as a highly pathogenic strain of bird flu has been spreading across North America.

This lineage of bird flu originated around 1996 and was first found in a domestic goose in China. The virus mutated and persisted, and the first big wild bird outbreak happened around 2005 in a major wetland in central Asia. Subsequent changes in the virus led to a 2014 introduction to the U.S. via the Pacific Northwest, severely affecting the U.S. poultry industry and forcing the culling of about 40 million turkeys and chickens as a control measure.

PFAS chemicals do not last forever

Once dubbed “forever chemicals,” per-and polyfluoroalkyl substances, or PFAS, might be in the market for a new nickname.

That’s because adding iodide to a water treatment reactor that uses ultraviolet (UV) light and sulfite destroys up to 90% of carbon-fluorine atoms in PFAS forever chemicals in just a few hours, reports a new study led by environmental engineering researchers at UC Riverside. The addition of iodide accelerates the speed of the reaction up to four times, saving energy and chemicals.

“Iodide is really doing some substantial work,” said corresponding author Jinyong Liu, an assistant professor of chemical and environmental engineering. “Not only does it speed up the reaction but it also allows the treatment of a ten times higher concentrations of PFAS, even some very recalcitrant structures.”

Liu’s lab has been working on ways to destroy PFAS through photochemical reactions since 2017. The new method has already attracted interest from industry and Liu’s group is partnering with companies to conduct pilot tests.

Synthetic chemicals known as PFAS contain multiple very strong carbon-fluorine bonds. Widespread use of these nonbiodegradable compounds in countless products since the 1940s has contaminated water supplies across America, with various negative health effects on humans and animals. Because the carbon-fluorine bond is very hard to break, PFAS pass through most water treatment systems unchanged.

Research Confirms Eastern Wyoming Paleoindian Site as Americas’ Oldest Mine

UW Ph.D. student Chase Mahan inspects an artifact from excavation at the Powars II archaeological site in 2020. Mahan is one of the co-authors of a new paper that confirms the site at Sunrise in Platte County is the oldest documented red ocher mine -- and likely the oldest known mine of any sort -- in all of North and South America.
Credit: Spencer Pelton

Archaeological excavations led by Wyoming’s state archaeologist and involving University of Wyoming researchers have confirmed that an ancient mine in eastern Wyoming was used by humans to produce red ocher starting nearly 13,000 years ago.

That makes the Powars II site at Sunrise in Platte County the oldest documented red ocher mine -- and likely the oldest known mine of any sort -- in all of North and South America. The excavations, completed shortly before the 2020 death of famed UW archaeologist George Frison, confirmed theories he advanced stemming from research he began at the site in 1986.

The findings appear in “In situ evidence for Paleoindian hematite quarrying at the Powars II site (48PL330), Wyoming,” a paper published in the Proceedings of the National Academy of Sciences (PNAS), one of the world’s most prestigious multidisciplinary scientific journals covering the biological, physical and social sciences.

Low-cost battery-like device absorbs CO2 emissions while it charges

Co-authors Israel Temprano and Grace Mapstone 
Credit: Gabriella Bocchetti

The supercapacitor device, which is similar to a rechargeable battery, is the size of a two-pence coin, and is made in part from sustainable materials including coconut shells and seawater.

Designed by researchers from the University of Cambridge, the supercapacitor could help power carbon capture and storage technologies at much lower cost. Around 35 billion tons of CO2 are released into the atmosphere per year and solutions are urgently needed to eliminate these emissions and address the climate crisis. The most advanced carbon capture technologies currently require large amounts of energy and are expensive.

The supercapacitor consists of two electrodes of positive and negative charge. In work led by Trevor Binford while completing his Master’s degree at Cambridge, the team tried alternating from a negative to a positive voltage to extend the charging time from previous experiments. This improved the supercapacitor’s ability to capture carbon.

“We found that that by slowly alternating the current between the plates we can capture double the amount of CO2 than before,” said Dr Alexander Forse from Cambridge’s Yusuf Hamied Department of Chemistry, who led the research.

Using Light and Sound to Reveal Rapid Brain Activity in Unprecedented Detail

The image shows the vasculature of the brain, and the colors illuminate how capillaries experience varying levels of oxygenation as the brain undergoes hypoxia.
Credit: Duke University

Duke researchers use a combination of hardware innovations and machine learning algorithms to create the fastest photoacoustic imaging tool available

Biomedical engineers at Duke University have developed a method to scan and image the blood flow and oxygen levels inside a mouse brain in real-time with enough resolution to view the activity of both individual vessels and the entire brain at once.

This new imaging approach breaks long-standing speed and resolution barriers in brain imaging technologies and could uncover new insights into neurovascular diseases like stroke, dementia and even acute brain injury.

The research appeared in the Nature journal Light: Science & Applications.

Imaging the brain is a balancing act. Tools need to be fast enough to capture rapid events, like a neuron firing or blood flowing through a capillary, and they need to show activity at different scales, whether it’s across the entire brain or at the level of a single artery.

New brain-painting method developed at USF is being tested for ADHD treatment

The brain painting method developed at USF is being tested for ADHD treatment.
Credit: University of South Florida

Imagine focusing on one thing so well that you can control its movement. Now, imagine mentally selecting colors and shapes to create an abstract image – a brain painting. USF computer scientist Marvin Andujar is harnessing the power of concentration and art to develop a new brain-computer interface (BCI) prototype and help study participants use their brain like never before. The goal is to introduce a novel treatment option for individuals with Attention-Deficit/Hyperactivity Disorder (ADHD) by tapping directly into their brain activity.

“This type of brain-computer interaction is more of a brain exercise to improve your attention,” Andujar said. “We’re trying to see how we can narrow that focus over time.”

Similar to Andujar’s previous work with brain-controlled drones, participants’ complete attention is required. To fly forward, a user must focus on a specific movement, such as walking. Individuals from the ADHD community approached Andujar after learning how the brain-controlled drone project harnessed attention span and asked for a device they could use at home.

A drone for ultrafast transitions between air and water

The new drone with a fish-inspired suction disc hitchhikes on moving objects to save power and can quickly transition between air and water.
Illustration: Beihang University / Science Robotics

A new robot is capable of switching from an underwater drone to an aerial vehicle in less than one second. The robot also features a suction disc inspired by the remora fish, which enables it to hitchhike on wet or dry moving objects to significantly reduce its power consumption. It is designed for biological and environmental monitoring in marine ecosystems such as surveying ocean pollution in the open sea as the scientist of Beihang University, Imperial College London and Empa point out in a new study published in Science Robotics.

The ultrafast transition from underwater drone to aerial vehicle in less than one second is based on a new propeller design – making this transition between the different mediums faster than most prior aerial-aquatic robots. Designed by a team of scientists from China, the United Kingdom and Switzerland, the versatile robot and its bio-inspired adhesive disc could be adapted for open-environment aerial and aquatic surveillance research.

Travelling with whales

The robot features a suction pad inspired by remora fish.
Image: Beihang University / Science Robotics

It’s well known that untethered drones can help research expeditions and wildlife surveys in expansive or remote environments such as the open sea, but some constraints remain. For example, untethered drones are not the best choice to use during lengthier missions because they have no external power sources to fall back on if their battery fails. To address this limitation, scientists 3D-printed an aerial-aquatic untethered robot that reduces its power consumption through hitchhiking. The robot features a suction pad inspired by remora fish – a family of species known for their adhesive discs, which help them catch a ride on marine creatures including whales and sharks. The remote-controlled robot’s disc can stick to wet and dry surfaces with different textures, even on moving objects.

In tests, the robot hitched a ride on a swimming host vehicle to obtain seabed images of hermit crabs, scallops, and seaweed. „Our study shows how we can take inspiration from the adhesion mechanism of the Remora and combine it with aerial robotics systems to achieve novel mobility methods for robotics“, says Mirko Kovac, who heads both Empa's Materials and Technology Center of Robotics and the Aerial Robotics Lab at Imperial College.

During the process, the hitchhiking robot consumed almost 20-times less energy than it would have using self-propulsion. Through their outdoor experiments, the team could show that the robot can hitchhike, record video during air-water transitions, and perform cross-medium retrieval operations in both freshwater and saltwater environments.

Ultrafast transition between water and air – the new bioinspired robot. 
Video: Empa / Source: Beihang University / Science Robotics

Source/Credit: EMPA


Astronauts may one day drink water from ancient moon volcanoes

Scientists believe that the moon's snakelike
Schroeter's Valley was created by lava flowing over the surface.
Credit: NASA Johnson
Billions of years ago, a series of volcanic eruptions broke loose on the moon, blanketing hundreds of thousands of square miles of the orb’s surface in hot lava. Over the eons, that lava created the dark blotches, or maria, that give the face of the moon its familiar appearance today.

New research from CU Boulder suggests that volcanoes may have left another lasting impact on the lunar surface: sheets of ice that dot the moon’s poles and, in some places, could measure dozens or even hundreds of feet thick.

“We envision it as a frost on the moon that built up over time,” said Andrew Wilcoski, lead author of the new study and a graduate student in the Department of Astrophysical and Planetary Sciences (APS) and the Laboratory for Atmospheric and Space Physics (LASP) at CU Boulder.

He and his colleagues published their findings this month in The Planetary Science Journal.

The researchers drew on computer simulations, or models, to try to recreate conditions on the moon long before complex life arose on Earth. They discovered that ancient moon volcanoes spewed huge amounts of water vapor, which then settled onto the surface—forming stores of ice that may still be hiding in lunar craters. If any humans had been alive at the time, they may even have seen a sliver of that frost near the border between day and night on the moon's surface.

It’s a potential bounty for future moon explorers who will need water to drink and process into rocket fuel, said study co-author Paul Hayne.

“It’s possible that 5 or 10 meters below the surface, you have big sheets of ice,” said Hayne, assistant professor in APS and LASP.

Tooth unlocks mystery of Denisovans in Asia

Views of the TNH2-1 specimen
Credit: Flinders University

What links a finger bone and some fossil teeth found in a cave in the remote Altai Mountains of Siberia to a single tooth found in a cave in the limestone landscapes of tropical Laos?

The answer to this question has been established by an international team of researchers from Laos, Europe, the US and Australia.

The human tooth was chanced upon during an archaeological survey in a remote area of Laos. The scientists have shown it originated from the same ancient human population first recognized in Denisova Cave (dubbed the Denisovans), in the Altai Mountains of Siberia (Russia).

The research team made the significant discovery during their 2018 excavation campaign in northern Laos. The new cave Tam Ngu Hao 2, also known as Cobra Cave, is located near to the famous Tam Pà Ling Cave where another important 70,000-year-old human (Homo sapiens) fossils had been previously found.

The international researchers are confident the two ancient sites are linked to Denisovans occupations despite being thousands of kilometers apart.

How ice clouds develop – Asian monsoon influences large parts of the Northern Hemisphere

Air pollutants form the condensation nuclei for ice clouds or cirrus clouds (here: Cirrus spissatus). When ammonia, nitric acid and sulfuric acid are present together, they form such condensation nuclei particularly effectively.
Credit: Joachim Curtius, Goethe-University Frankfurt

Atmospheric researchers from the international CLOUD consortium have discovered a mechanism that allows nuclei for ice clouds to form and rapidly grow in the upper troposphere. The discovery is based on cloud chamber experiments to which a team from Goethe University contributed highly specialized measurements. Although the conditions for nucleus formation are only fulfilled in the Asian monsoon region, the mechanism is expected to have an impact on ice cloud formation across large parts of the Northern Hemisphere. 

The Asian monsoon transports enormous amounts of air from atmospheric layers close to Earth's surface to a height of around 15 kilometers. Like in a gigantic elevator, human-induced pollutants also end up in the upper troposphere in this way. A research team from the CLOUD consortium (Cosmics Leaving Outdoor Droplets), including atmospheric researchers from Goethe University in Frankfurt, have reproduced the conditions prevailing there, among them cosmic radiation, in their experimental chamber at the CERN particle accelerator center in Geneva.

Biological crusts influence the climate

Biological soil crusts strengthen the soil and ensure that less sand is stirred up and thus fewer dust particles are released into the atmosphere.
Credit: Emilio Rodriguez-Caballero

A surface layer of bacteria, fungi and lichen amongst others reduces the amount of dust stirred up into the atmosphere

When bacteria, fungi, mosses, lichens and algae combine on dry land, they form so-called biological soil crusts. These cover about twelve percent of the total global land surface, and up to one third of the surface in dry areas. Biological soil crusts play an important role in consolidating soils, making them more stable and less likely to be stirred up by the wind. Since dust particles in the atmosphere have an impact on the climate, soil crusts fulfil an important function in several respects. An international team of researchers around biologist Bettina Weber of the University of Graz and research associate of the Max Planck Institute for Chemistry provide, for the first time, comprehensive facts and figures on the importance of biological soil crusts for the regional and global dust cycle, both under current and future conditions.

The dwarf planet Ceres was formed in the coldest zone of Solar System and thrust into Asteroid Belt

The dwarf planet Ceres in an image captured by NASA’s Dawn Mission. The bright white spot is a reflection of sunlight from ice deposits at the bottom of the crater

In an article published in the journal Icarus, researchers at São Paulo State University (UNESP) and collaborators report the findings of a study reconstituting the formation of the dwarf planet Ceres.

The research was conducted by Rafael Ribeiro de Sousa, a professor in the program of graduate studies in physics on the Guaratinguetá campus. The co-authors of the article are Ernesto Vieira Neto, who was Ribeiro de Sousa’s PhD thesis advisor, and researchers affiliated with Côte d’Azur University in France, Rice University in the United States, and the National Observatory in Rio de Janeiro.

Ceres is the largest object in the Asteroid Belt, a collection of celestial bodies located between the orbits of Mars and Jupiter. It is roughly spherical and comprises a third of the Asteroid Belt’s total mass, with a diameter of almost 1,000 km, less than a third of the Moon’s.

Its orbit around the Sun is almost perfectly circular, with 0.09 eccentricity, and an inclination of 9.73° to the invariable plane of the Solar System, much greater than Earth’s, which is 1.57°.

Researchers developed invisible, machine-washable solar cell technology for clothing

The Sun-powered Textiles project looked for ways to seamlessly combine solar cells and textiles. Photo: Anne Kinnunen/Aalto University

The discrete nature of the cells protects them – and makes the clothes more attractive, the physics and design researchers say. Promising applications include work and outdoor clothing, and curtains which react to changes in the amount of light.

Lasting power and efficient recycling

Any solar cell placed under the textile it adheres to has to have a significantly larger surface area than a cell that’s placed on top. A piece of regular fabric eats up roughly 70 percent of a cell’s capacity - with a more porous fabric the percentage is smaller.

Key factors in the ability of textiles to let light through them include the material, transparency and crosscut of the fiber, structure of the threads, thickness and weave of the fabric, colors and the finish. Light colors transmit light better than dark colors, but a pitch-black and completely opaque fabric can also work.

The commercial solar cells used in the study comprised of a single crystal and were made of silicon. They can detect light that is invisible to the naked eye, which is what most sunlight actually is. Infrared is an example of such invisible light.

Mystery of seafloor metamorphosis unlocked

An adult tubeworm, in its tube, with its plume of tentacles extended.
Photo credit: Freckelton et al. 2022

Most bottom-dwelling marine invertebrate animals, such as sponges, corals, worms and oysters, produce tiny larvae that swim in the ocean prior to attaching to the seafloor and transforming into juveniles. A study published in the Proceedings of the National Academy of Sciences and led by University of Hawaiʻi at Mānoa researchers revealed that a large, complex molecule, called lipopolysaccharide, produced by bacteria is responsible for inducing larval marine tubeworms, Hydroides elegans, to settle to the seafloor and begin the complex processes of metamorphosis.

“This is a major milestone in understanding the factors that determine where larvae of bottom-living invertebrates settle and metamorphose,” said Michael Hadfield, senior author on the paper and emeritus professor in the UH Mānoa School of Ocean and Earth Science and Technology (SOEST). “It is the key to understanding how benthic (underwater) communities are established and maintained on all surfaces under salt water, that is, on 71% of Earth’s surface.”

Scientists 'see' puzzling features deep in Earth’s interior

Etna Volcano Eruption January 12th 2011
Credit: gnuckx

New research led by the University of Cambridge is the first to obtain a detailed 'image' of an unusual pocket of rock at the boundary layer with Earth’s core, some three thousand kilometers beneath the surface.

The enigmatic area of rock, which is located almost directly beneath the Hawaiian Islands, is one of several ultra-low velocity zones – so-called because earthquake waves slow to a crawl as they pass through them.

The research, published in Nature Communications, is the first to reveal the complex internal variability of one of these pockets in detail, shedding light on the landscape of Earth’s deep interior and the processes operating within it.

“Of all Earth’s deep interior features, these are the most fascinating and complex. We’ve now got the first solid evidence to show their internal structure - it’s a real milestone in deep earth seismology,” said lead author Zhi Li, PhD student at Cambridge’s Department of Earth Sciences.

Wednesday, May 18, 2022

“Natural Immunity” from Omicron is Weak and Limited

The new study shows that infection with Omicron does not protect against other variants of COVID-19. In this photo, clear zones on the purple background show the SARS-CoV-2 virus escaping from neutralizing antibodies in patient blood samples.
Credit: Gladstone Institutes

In unvaccinated people, infection with the Omicron variant of SARS-CoV-2 provides little long-term immunity against other variants, according to a new study by researchers at Gladstone Institutes and UC San Francisco (UCSF), published today in the journal Nature.

In experiments using mice and blood samples from donors who were infected with Omicron, the team found that the Omicron variant induces only a weak immune response. In vaccinated individuals, this response—while weak—helped strengthen overall protection against a variety of COVID-19 strains. In those without prior vaccination, however, the immune response failed to confer broad, robust protection against other strains.

“In the unvaccinated population, an infection with Omicron might be roughly equivalent to getting one shot of a vaccine,” says Melanie Ott, MD, PhD, director of the Gladstone Institute of Virology and co-senior author of the new work. “It confers a little bit of protection against COVID-19, but it’s not very broad.”

Banned Contaminants Still Threaten Endangered California Condors

Condors at Pinnacles National Park in central California.
Photo courtesy of San Diego Zoo Wildlife Alliance

A new study has found contaminants that were banned decades ago are still imperiling critically endangered California condors. The condors may be at increased risk for reproductive impairment because they consume dead marine mammals along the California coast.

The research, led by San Diego State University (SDSU) and San Diego Zoo Wildlife Alliance (SDZWA) scientists, in collaboration with Centro de Investigación Científica y de Educación Superior de Ensenada and the National Oceanographic and Atmospheric Administration, found that marine mammals stranded on the California coast harbor relatively high levels of halogenated organic contaminants (HOCs). Researchers detected more than 400 contaminants in samples taken from stranded marine mammals that California condors may feed on.

On the California coast, the marine mammals had an estimated seven times more DDT and 3.5 times more PCBs than their counterparts in Baja California, Mexico. Other lesser-studied compounds were also detected. One group of these compounds was estimated to be 148 times more abundant in California marine mammals compared to those in Baja California.

The study, published in the journal Environmental Science & Technology, also reveals that coastal condors have more contaminants in their blood than inland condors, which lack a marine mammal diet.

Choline makes key nutrients available for baby development

Choline Molecule 
Choline occurs in foods as a free molecule and in the form of phospholipids, especially as phosphatidylcholines. Choline is highest in organ meats and egg yolks though it is found to a lesser degree in non-organ meats, grains, vegetables, fruit and dairy products.

The nutrient choline – shown to have long-term benefits for children whose mothers consume it during pregnancy – also helps the body more efficiently use an omega 3 fatty acid that is essential for fetal brain, cognition and vision development, a new study finds.

The study was published in the American Journal of Clinical Nutrition.

The findings show that choline supplementation supports cellular metabolism to more efficiently handle and release the omega 3 fatty acid, DHA, from a pregnant individual’s liver. Once released into the bloodstream, DHA can be delivered into all the tissues, including the placenta.

“During pregnancy, mom is primed to get nutrients out of the liver and make them available to the baby, so by supplementing choline and DHA [together], we are increasing DHA bioavailability,” said senior author Marie Caudill, professor of nutritional sciences in the College of Agriculture and Life Sciences. Kevin Klatt, Ph.D. ’18, a research scientist and registered dietitian at the University of California, Berkeley, is the paper’s first author.

Rainforest trees may have been dying faster since the 1980s because of climate change

Northeast Australia's relict tropical rainforest are one of the oldest most isolated rainforests in the world.
Photo credit: Alexander Schenkin

Tropical trees in Australia’s rainforests have been dying at double the previous rate since the 1980s, seemingly because of climate impacts, according to the findings of a long-term international study published in Nature today. This research has found the death rates of tropical trees have doubled in the last 35 years, as global warming increases the drying power of the atmosphere.

Deterioration of such forests reduces biomass and carbon storage, making it increasingly difficult to keep global peak temperatures well below the target 2 °C, as required by the Paris Agreement. Today’s study, led by researchers from the Smithsonian Environmental Research Center and Oxford University, and French National Research Institute for Sustainable Development (IRD), has used uniquely long data records from across Australia’s rainforests.

It finds average tree death rates in these forests have doubled over the past four decades. Researchers found trees are living around half as long, which is a pattern consistent across species and sites across the region. And the impacts can be seen as far back as the 1980s, according to the team.

Researchers Use Galaxy as a ‘Cosmic Telescope’ to Study Heart of the Young Universe

An artist’s rendering shows how a cluster of galaxies (lensing cluster) acts as a gravitational lens that magnifies and extends the light from a background galaxy.
Image: W. M. Keck Observatory/Adam Makarenko

A unique new instrument, coupled with a powerful telescope and a little help from nature, has given researchers the ability to peer into galactic nurseries at the heart of the young universe.

After the big bang some 13.8 billion years ago, the early universe was filled with enormous clouds of neutral diffuse gas, known as Damped Lyman-α systems, or DLAs. These DLAs served as galactic nurseries, as the gases within slowly condensed to fuel the formation of stars and galaxies. They can still be observed today, but it isn’t easy.

“DLAs are a key to understanding how galaxies form in the universe, but they are typically difficult to observe since the clouds are too diffuse and don’t emit any light themselves,” says Rongmon Bordoloi, assistant professor of physics at North Carolina State University and corresponding author of the research.

Currently, astrophysicists use quasars – supermassive black holes that emit light – as “backlight” to detect the DLA clouds. And while this method does allow researchers to pinpoint DLA locations, the light from the quasars only acts as small skewers through a massive cloud, hampering efforts to measure their total size and mass.

But Bordoloi and John O’Meara, chief scientist at the W.M. Keck Observatory in Kamuela, Hawaii, found a way around the problem by using a gravitationally lensed galaxy and integral field spectroscopy to observe two DLAs – and the host galaxies within – that formed around 11 billion years ago, not long after the big bang.

“Gravitationally lensed galaxies refer to galaxies that appear stretched and brightened,” Bordoloi says. “This is because there is a gravitationally massive structure in front of the galaxy that bends the light coming from it as it travels toward us. So, we end up looking at an extended version of the object – it’s like using a cosmic telescope that increases magnification and gives us better visualization.

“The advantage to this is twofold: One, the background object is extended across the sky and bright, so it is easy to take spectrum readings on different parts of the object. Two, because lensing extends the object, you can probe very small scales. For example, if the object is one light year across, we can study small bits in very high fidelity.”

Spectrum readings allow astrophysicists to “see” elements in deep space that are not visible to the naked eye, such as diffuse gaseous DLAs and the potential galaxies within them. Normally, gathering the readings is a long and painstaking process. But the team solved that issue by performing integral field spectroscopy with the Keck Cosmic Web Imager.

Integral field spectroscopy allowed the researchers to obtain a spectrum at every single pixel on the part of the sky it targeted, making spectroscopy of an extended object on the sky very efficient. This innovation combined with the stretched and brightened gravitationally lensed galaxy allowed the team to map out the diffuse DLA gas in the sky at high fidelity. Through this method the researchers were able to determine not only the size of the two DLAs, but also that they both contained host galaxies.

“I’ve waited most of my career for this combination: a telescope and instrument powerful enough, and nature giving us a bit of lucky alignments to study not one but two DLAs in a rich new way,” O’Meara says. “It’s great to see the science come to fruition.”

The DLAs are huge, by the way. With diameters greater than 17.4 kiloparsecs, they’re more than two thirds the size of the Milky Way galaxy today. For comparison, 13 billion years ago, a typical galaxy would have a diameter of less than 5 kiloparsecs. A parsec is 3.26 light years, and a kiloparsec is 1,000 parsecs, so it would take light about 56,723 years to travel across each DLA.

“But to me, the most amazing thing about the DLAs we observed is that they aren’t unique – they seem to have similarities in structure, host galaxies were detected in both, and their masses indicate that they contain enough fuel for the next generation of star formation,” Bordoloi says. “With this new technology at our disposal, we are going to be able to dig deeper into how stars formed in the early universe.”

The work appears in Nature and was supported by the National Aeronautics and Space Administration, the W.M. Keck Foundation and the National Science Foundation. The Australian Research Council Centre of Excellence for All Sky Astrophysics in 3 Dimensions (ASTRO 3D) also contributed to the work.

Source/Credit: North Carolina State University | Tracey Peake


Spying on Thousands of Neurons in the Brain’s Vision Center Simultaneously

Scientists tracked how individual neurons (white dots)
across the mouse visual center responded when the
animals saw an image on a screen.
That let the team trace the sequence
of events triggered when the eyes detect an important sight.
Credit: S. Ebrahimi et al./Nature 2022
Using a custom-built microscope to peer into the mouse brain, scientists have tracked the activity of single neurons across the entire visual cortex.

These recordings, made in the tenths of seconds after the animals saw a cue on a screen, expose the complex dynamics involved in making sense of what the eyes see. In an unprecedented combination of breadth and detail, the results describe the behavior of more than 21,000 total neurons in six mice over five days, Howard Hughes Medical Institute Investigator Mark Schnitzer’s team reports in the journal Nature on May 18, 2022.

His team is the first to get a glimpse of individual cells’ activity occurring at the same time throughout eight parts of the brain involved in vision. “People have studied these brain areas before, but prior imaging studies did not have cellular resolution across the entire visual cortex,” says Schnitzer, a neuroscientist at Stanford University.

The work highlights the dramatic sequence of events that unfolds in the brain from the instant it receives messages from the eyes until it decides how to respond to that sight. The researchers’ far-reaching but fine-grained imaging approach made it possible for them to collect an “incredible” set of data, says Tatiana Engel, a computational neuroscientist at Cold Spring Harbor Laboratory who was not involved in the study.

A component for brain-inspired computing

Scientists aim to perform machine-learning tasks more efficiently with processors that emulate the working principles of the human brain.
Image: Unsplash

Researchers from ETH Zurich, Empa and the University of Zurich have developed a new material for an electronic component that can be used in a wider range of applications than its predecessors. Such components will help create electronic circuits that emulate the human brain and that are more efficient than conventional computers at performing machine-learning tasks.

Compared with computers, the human brain is incredibly energy-efficient. Scientists are therefore drawing on how the brain and its interconnected neurons function for inspiration in designing innovative computing technologies. They foresee that these brain-inspired computing systems will be more energy-efficient than conventional ones, as well as better at performing machine-learning tasks.

Much like neurons, which are responsible for both data storage and data processing in the brain, scientists want to combine storage and processing in a single type of electronic component, known as a memristor. Their hope is that this will help to achieve greater efficiency because moving data between the processor and the storage, as conventional computers do, is the main reason for the high energy consumption in machine-learning applications.

At-Risk Sea Life in the Atlantic Needs Better Protection from an Increase in Shipping

Researchers at the University of Portsmouth have discovered that rates of shipping in the North East Atlantic area rose by 34 per cent in a five-year period.

Even more noticeable, and of major concern to scientists, is the rate of shipping growth in Marine Protected Areas. Analysis of vessel movements in these delicate environments shows an increase of 73 per cent in the same time period.

The report, which was published in Marine Pollution Bulletin, is the first detailed survey of shipping activity in the North East Atlantic. Researchers used data from over 530 million vessel positions recorded by Automatic identification Systems (AIS). They looked at the change in shipping between 2013 and 2017 across ten distinct vessel types.

In total the study area covered 1.1 million km2, including waters off Belgium, Denmark, France, Germany, Iceland, Ireland, The Netherlands, Norway, Portugal, Spain, and the UK.

Renewed monitoring effort is needed to ensure that protective measures are adequate to conserve species under threat in a changing environment.

For Plant-based Proteins, Soy is a Smart Choice

Tofu, flour, milk, and sauce are just some of the products that can be made from the versatile plant protein soy

Soy – the versatile protein source that comes from the species of legumes known as soybeans – is becoming a popular alternative to meat and dairy products, and for good reason. Whether you are trying to eat healthier, eat more sustainably, or both, College of Agriculture, Health and Natural Resources Department of Nutritional Sciences researcher Yangchao Luo and his research group recently published an article in the Journal of Agriculture and Food Research exploring qualities that make soy a versatile and nutritious choice.

What makes soy such a popular source of plant-based meat (and dairy) alternatives?

In comparison to other plant-based proteins, soy protein provides the most complete nutrients in terms of amino acids, compared to animal sources. Soy contains almost every amino acid, with only one minor exception, methionine, which is an essential amino acid, and what we call a limiting amino acid. Other plant-based proteins may miss two, three, or even four different essential amino acids. You can easily get all essential amino acids in a meal by mixing plant-based proteins or by pairing soy-based proteins with grains.

Upon extrusion process, soy-based proteins undergo a series of physicochemical changes to form fibrous anisotropic structure, the texture of which becomes very similar to meat products. When modified chemically or enzymatically, soy protein can further develop sensory characteristics that can mimic real meat. This is very easy to do for soy protein, but more challenging for many other plant proteins. A lot of food companies nowadays are trying to develop meat alternatives, and soy-based protein is just the top choice for the food industries.

Ultrahigh piezoelectric performance demonstrated in ceramic materials

The ability of piezoelectric materials to convert mechanical energy into electrical energy and vice versa makes them useful for various applications from robotics to communication to sensors. A new design strategy for creating ultrahigh-performing piezoelectric ceramics opens the door to even more beneficial uses for these materials, according to a team of researchers from Penn State and Michigan Technological University.

“For a long time, piezoelectric polycrystalline ceramics have shown limited piezoelectric response in comparison to single crystals,” said Shashank Priya, associate vice president for research and professor of materials science and engineering at Penn State and co-author of the study published in the journal Advanced Science. “There are many mechanisms that limit the magnitude of piezoelectricity in polycrystalline ceramic materials. In this paper, we demonstrate a novel mechanism that allows us to enhance the magnitude of the piezoelectric coefficient several times higher than is normally expected for a ceramic.”

The piezoelectric coefficient, which describes the level of a material's piezoelectric response, is measured in picocoulombs per Newton.

“We achieved close to 2,000 picocoulombs per Newton, which is a significant advance, because in polycrystalline ceramics, this magnitude has always been limited to around 1,000 picocoulombs per Newton,” Priya said. "2,000 was considered an unreachable target in the ceramics community, so achieving that number is very dramatic.”

Tuesday, May 17, 2022

Rice chemists skew the odds to prevent cancer

A new paper by a Rice University lab shows how to increase the odds of identifying cancer-causing mutations before tumors take hold. Authors are, from left, Cade Spaulding, Anatoly Kolomeisky and Hamid Teimouri.
Credit: Rice University

The path to cancer prevention is long and arduous for legions of researchers, but new work by Rice University scientists shows that there may be shortcuts.

Rice chemist Anatoly Kolomeisky, lead author and postdoctoral researcher Hamid Teimouri and research assistant Cade Spaulding are developing a theoretical framework to explain how cancers caused by more than one genetic mutation can be more easily identified and perhaps stopped.

Essentially, it does so by identifying and ignoring transition pathways that don’t contribute much to the fixation of mutations in a cell that goes on to establish a tumor.

A study in the Biophysical Journal describes their analysis of the effective energy landscapes of cellular transformation pathways implicated in a variety of cancers. The ability to limit the number of pathways to the few most likely to kick-start cancer could help to find ways to halt the process before it ever really starts.

“In some sense, cancer is a bad-luck story,” said Kolomeisky, a professor of chemistry and of chemical and biomolecular engineering. “We think we can decrease the probability of this bad luck by looking for low-probability collections of mutations that typically lead to cancer. Depending on the type of cancer, this can range between two mutations and 10.”

Technology allows amputees to control a robotic arm with their mind

University of Minnesota Department of Biomedical Engineering Associate Professor Zhi Yang shakes hands with research participant Cameron Slavens, who tested out the researchers' robotic arm system. With the help of industry collaborators, the researchers have developed a way to tap into a patient’s brain signals through a neural chip implanted in the arm, effectively reading the patient’s mind and opening the door for less invasive alternatives to brain surgeries.
Credit: Neuroelectronics Lab, University of Minnesota

University of Minnesota Twin Cities researchers have developed a more accurate, less invasive technology that allows amputees to move a robotic arm using their brain signals instead of their muscles.

Many current commercial prosthetic limbs use a cable and harness system that is controlled by the shoulders or chest, and more advanced limbs use sensors to pick up on subtle muscle movements in a patient’s existing limb above the device. But both options can be cumbersome, unintuitive, and take months of practice for amputees to learn how to move them.

Researchers in the University’s Department of Biomedical Engineering, with the help of industry collaborators, have created a small, implantable device that attaches to the peripheral nerve in a person’s arm. When combined with an artificial intelligence computer and a robotic arm, the device can read and interpret brain signals, allowing upper limb amputees to control the arm using only their thoughts.

Scent dogs detect coronavirus reliably from skin swabs

Scent dog Silja at the Helsinki-Vantaa airport.
Credit: Egil Björkman

The rapid and accurate identification and isolation of patients with coronavirus infection is an important part of global pandemic management. The current diagnosis of coronavirus infection is based on a PCR test that accurately and sensitively identifies coronavirus from other pathogens. However, PCR tests are ill-suited for screening large masses of people because of, among other things, their slow results and high cost.

Researchers from the Faculties of Veterinary Medicine and Medicine at the University of Helsinki and from Helsinki University Hospital jointly designed a triple-blind, randomized, controlled study set-up to test the accuracy of trained scent detection dogs where none of the trio – dog, dog handler or researcher – knew which of the sniffed skin swab samples were positive and which negative. The study also analyzed factors potentially interfering with the ability of the dogs to recognize a positive sample.

The three-faceted study has now been published in the journal BMJ Global Health. The study provides valuable information on the use of scent dogs in pandemic control.

Scientists Nail Down 'Destination' for Protein That Delivers Zinc

Brookhaven Lab biologist Crysten Blaby and postdoctoral fellow Nicolas Grosjean and colleagues ran genetic experiments, biochemical assays, and computational modeling studies that identified ZNG1 as a zinc chaperone protein.
Credit: Brookhaven National Laboratory

Most people don’t think much about zinc. But all living things need zinc for survival. This trace element helps many proteins fold into the right shapes to do their jobs. And in proteins known as enzymes, zinc helps catalyze chemical reactions—including many important for providing energy to cells. If zinc is absent, people, pets, and plants don’t thrive.

That’s one reason biologists at the U.S. Department of Energy’s Brookhaven National Laboratory are so interested in this element.

“We're looking for ways to grow bioenergy plants—either plants that produce biofuels or whose biomass can be converted into fuel—and doing it on land that is not suitable for growing food crops,” said Brookhaven Lab biologist Crysten Blaby, who also holds an adjunct appointment at Stony Brook University. “So, we’re interested in strategies nature uses to survive when zinc and other micronutrients are lacking.”

In a paper just published in the journal Cell Reports, Blaby and her colleagues describe one such strategy: a so-called “chaperone” protein that delivers zinc to where it’s needed, which could be especially important when access to zinc is limited. Though scientists, including Blaby, have long suspected the existence of a zinc chaperone, the new research provides the first definitive evidence by identifying a “destination” for its deliveries.

A new mathematical model of cellular movement

A new mathematical model describes how cells change their shape during movement and suggests that the movement is mainly driven by the contraction of the skeletal proteins, called “myosin.” The image shows the shape of cells at various speeds as predicted by the model. Non-moving cells are circular but become asymmetric as they begin to move. The colors indicate the concentration of myosin in the cell with red indicating a higher concentration.
Credit: C. Alex Safsten, Penn State

A mathematical model that describes how cells change their shape during movement suggests that the movement is mainly driven by the contraction of the skeletal proteins, called “myosin.” The new model developed at Penn State can help researchers to better understand the various biological processes where cellular movement plays a key role and also could inform the development of artificial systems that mimic biological processes.

“The focus of this work is on the development of minimal mathematical models that are simple enough to be amenable to rigorous analysis but still capture key biological phenomena,” said Leonid Berlyand, professor of mathematics at Penn State and the leader of this research team. “The point of our model is to capture the onset of cell motion driven by myosin contraction with focus on analyzing the stability of this motion observed in experiments.”

For large bone injuries, it’s Sonic hedgehog to the rescue

After surgical rib resection (top), a cartilage and bone bridge form (second from top) and then resolve (third from top) and remodel to regenerate the missing tissue in the gap (bottom). Blue shows cartilage matrix; red shows mineralized matrix.
Images by Stephanie Kuwahara and Max Serowoky/ Mariani Lab

A USC Stem Cell study in NPJ Regenerative Medicine presents intriguing evidence that large bone injuries might trigger a repair strategy in adults that recapitulates elements of skeletal formation in utero. Key to this repair strategy is a gene with a fittingly heroic name: Sonic hedgehog.

In the study, first author Maxwell Serowoky, a PhD student in the USC Stem Cell laboratory of Francesca Mariani, and his colleagues took a close look at how mice are able to regrow large sections of missing rib—an ability they share with humans, and one of the most impressive examples of bone regeneration in mammals.

To their surprise, the scientists observed an increase in the activity of Sonic hedgehog (Shh), which plays an important role in skeletal formation in embryos, but hasn’t previously been linked to injury repair in adults.

In their experiments, Shh appeared to play a necessary role in healing the central region of large sections of missing ribs, but not in closing small-scale fractures.

New Approach Allows for Faster Ransomware Detection

Photo credit: Michael Geiger

Engineering researchers have developed a new approach for implementing ransomware detection techniques, allowing them to detect a broad range of ransomware far more quickly than previous systems.

Ransomware is a type of malware. When a system is infiltrated by ransomware, the ransomware encrypts that system’s data – making the data inaccessible to users. The people responsible for the ransomware then extort the affected system’s operators, demanding money from the users in exchange for granting them access to their own data.

Ransomware extortion is hugely expensive, and instances of ransomware extortion are on the rise. The FBI reports receiving 3,729 ransomware complaints in 2021, with costs of more than $49 million. What’s more, 649 of those complaints were from organizations classified as critical infrastructure.

Featured Article

Using Light and Sound to Reveal Rapid Brain Activity in Unprecedented Detail

The image shows the vasculature of the brain, and the colors illuminate how capillaries experience varying levels of oxygenation as the brai...

Top Viewed Articles