Novel Nanowire Fabrication Technique Paves Way for Next Generation Spintronics

The challenge of fabricating nanowires directly on silicon substrates for the creation of the next generation of electronics has finally been solved by researchers from Tokyo Tech. Next-generation spintronics will lead to better memory storage mechanisms in computers, making them faster and more efficient.

As our world modernizes faster than ever before, there is an ever-growing need for better and faster electronics and computers. Spintronics is a new system which uses the spin of an electron, in addition to the charge state, to encode data, making the entire system faster and more efficient. Ferromagnetic nanowires with high coercivity (resistance to changes in magnetization) are required to realize the potential of spintronics. Especially L10-ordered (a type of crystal structure) cobalt–platinum (CoPt) nanowires.

Conventional fabrication processes for L10-ordered nanowires involve heat treatment to improve the physical and chemical properties of the material, a process called annealing on the crystal substrate; the transfer of a pattern onto the substrate through lithography; and finally, the chemical removal of layers through a process called etching. Eliminating the etching process by directly fabricating nanowires onto the silicon substrate would lead to a marked improvement in the fabrication of spintronic devices. However, when directly fabricated nanowires are subjected to annealing, they tend to transform into droplets as a result of the internal stresses in the wire.

Low levels of air pollution deadlier than previously thought

Photo Credit: Ralf Vetterle

The World Health Organization’s most recent estimates (2016) are that over 4.2 million people die prematurely each year due to long-term exposure to fine particulate outdoor air pollution (often referred to as PM2.5,). A recent study involving McGill researchers now suggests that the annual global death toll from outdoor PM2.5 may be significantly higher than previously thought. That’s because the researchers found that mortality risk was increased even at very low levels of outdoor PM2.5, ones which had not previously been recognized as being potentially deadly. These microscopic toxins cause a range of cardiovascular and respiratory diseases and cancers.

“We found that outdoor PM2.5 may be responsible for as many as 1.5 million additional deaths around the globe each year because of effects at very-low concentrations that were not previously appreciated,” said Scott Weichenthal, an Associate Professor in the Department of Epidemiology, Biostatistics, and Occupational Health at McGill University and the lead author on the recent paper in Science Advances.

Tracing tomatoes’ health benefits to gut microbes

The tomatoes used in the study were developed at Ohio State and are the type typically found in canned tomato products.
Photo Credit: Couleur

Two weeks of eating a diet heavy in tomatoes increased the diversity of gut microbes and altered gut bacteria toward a more favorable profile in young pigs, researchers found.

After observing these results with a short-term intervention, the research team plans to progress to similar studies in people, looking for health-related links between tomatoes in the diet and changes to the human gut microbiome – the community of microorganisms living in the gastrointestinal tract.

“It’s possible that tomatoes impart benefits through their modulation of the gut microbiome,” said senior author Jessica Cooperstone, assistant professor of horticulture and crop science and food science and technology at The Ohio State University.

“Overall dietary patterns have been associated with differences in microbiome composition, but food-specific effects haven’t been studied very much,” Cooperstone said. “Ultimately we’d like to identify in humans what the role is of these particular microorganisms and how they might be contributing to potential health outcomes.”

UQ study explains link between sleep apnea and dementia

Professor Elizabeth Coulson said the findings suggest CPAP treatment of obstructive sleep apnea has the potential to reduce dementia risk.
Credit: University of Queensland

Researchers at The University of Queensland have discovered a link between obstructive sleep apnea and an increased risk of developing dementia.

Professor Elizabeth Coulson from UQ’s Queensland Brain Institute and School of Biomedical Sciences and her team found a causal relationship between a lack of oxygen to the brain during sleep and Alzheimer’s disease in mice.

“We found sleep deprivation alone in mice caused only mild cognitive impairment,” Professor Coulson said.

“But we developed a novel way to induce sleep-disrupted breathing and found the mice displayed exacerbated pathological features of Alzheimer’s disease.

“It demonstrated that hypoxia – when the brain is deprived of oxygen – caused the same selective degeneration of neurons that characteristically die in dementia.”

Professor Coulson said the next step would be to determine what levels of hypoxia result in brain degeneration in humans.

New quantum phase discovered for developing hybrid materials

 Metropolitan University Scientists have discovered that in Ba1-xSrxAl2O4, a highly disordered atomic arrangement is formed in the AlO4 network at chemical compositions near the structural quantum critical point, resulting in both characteristics of crystalline and amorphous materials.
Illustration Credit: Yui Ishii, Osaka

Scientists discovered a hybrid state in which crystals exhibit both crystalline and amorphous characteristics near the structural quantum critical point.

If you have ever watched water freeze to ice, you have witnessed what physicists call a “phase transition.” Osaka Metropolitan University scientists have discovered an unprecedented phase transition during which crystals achieve amorphous characteristics while retaining their crystalline properties. Their findings contribute to developing hybrid materials for use in harsh environments, such as outer space. The results were published in Physical Review B.

A typical phase transition exhibited by crystalline solids involves a change in the crystal structure. Such structural phase transitions usually occur at finite temperatures. However, controlling the chemical composition of the crystal can lower the transition temperature to absolute zero (−273°C). The transition point at absolute zero is called the structural quantum critical point.

Old Bone Links Lost American Parrot to Ancient Indigenous Bird Trade

A thick-billed parrot.
Photo Credit: U.S. Fish and Wildlife.

For centuries, Indigenous communities in the American Southwest imported colorful parrots from Mexico. But according to a study led by The University of Texas at Austin, some parrots may have been captured locally and not brought from afar.

The research challenges the assumption that all parrot remains found in American Southwest archaeological sites have their origins in Mexico. It also presents an important reminder: The ecology of the past can be very different from what we see today.

“When we deal with natural history, we can constrain ourselves by relying on the present too much,” said the study’s author, John Moretti, a doctoral candidate at the UT Jackson School of Geosciences. “These bones can give us kind of a baseline view of the animal life of the ecosystems that surrounded us before huge fundamental changes that continue today began.”

The study was published in print in the September issue of The Wilson Journal of Ornithology.

Study shows differences between brains of primates — humans, apes and monkeys — are small but significant

Researchers analyzed genetic material from cells in the prefrontal cortex (the area shaded in each brain) from four closely-related primates to characterize subtle differences in cell type and genetics.
Source/Credit: University of Wisconsin–Madison

While the physical differences between humans and non-human primates are quite distinct, a new study reveals their brains may be remarkably similar. And yet, the smallest changes may make big differences in developmental and psychiatric disorders.

Understanding the molecular differences that make the human brain distinct can help researchers study disruptions in its development. A new study, published recently in the journal Science by a team including University of Wisconsin–Madison neuroscience professor Andre Sousa, investigates the differences and similarities of cells in the prefrontal cortex — the frontmost region of the brain, an area that plays a central role in higher cognitive functions — between humans and non-human primates such as chimpanzees, Rhesus macaques and marmosets.

The cellular differences between these species may illuminate steps in their evolution and how those differences can be implicated in disorders, such as autism and intellectual disabilities, seen in humans. Sousa, who studies the developmental biology of the brain at UW–Madison’s Waisman Center, decided to start by studying and categorizing the cells in the prefrontal cortex in partnership with the Yale University lab where he worked as a postdoctoral researcher.

There’s room for improvement in a popular climate-smart agricultural practice

The promise for American agriculture is tantalizing: healthier soil, more carbon kept in the ground, less fertilizer runoff, and less need for chemicals. The reality of planting cover crops during the off-season – a much-touted and subsidized approach to climate change mitigation – is more complicated, according to new Stanford University-led research. The study, published Nov. 8 in Global Change Biology, reveals that cover cropping as currently done in a major U.S. crop-growing region reduces corn and soybean yields, and could lead to indirect environmental impacts from expanded cultivation to make up for the losses.

“Use of cover crops is rapidly spreading. We wanted to see how these new practices affect crop yields in the real world, outside of small-scale research plots,” said Jillian Deines, lead author of the study and a postdoctoral scholar in Stanford’s Center on Food Security and the Environment (FSE) at the time of the research.

“Agriculture is a very tricky business to get right, and things typically don’t work out as planned” added senior author David Lobell, the Gloria and Richard Kushel Director of FSE and professor in Earth System Science. “Our view is that constant monitoring, evaluation, and learning is a key part of making agriculture truly sustainable.”

New experimental treatment can stop the growth of schwannoma tumors

Researchers showed that after just 21 days of the drugs being administered, tumor growth can be strongly and significantly reduced.
Photo Credit: MART PRODUCTION

Two novel and orally administered drugs can not only block the growth, but also shrink the size, of a tumor type found in the nervous system, new research has shown.

The tumors, schwannomas, most frequently grow on the nerves that bring hearing and balance information into the brain. Schwannomas are the most common nerve sheath tumor, and can occur in anyone but are also linked to a hereditary condition known as Neurofibromatosis Type II (NF2).

In NF2, where the function of the protein Merlin is lost in cells, patients frequently develop not only schwannomas, but also meningioma tumors associated with the brain and spinal cord.

The treatment of both tumor types is difficult, with surgery being the current mainstay but also carrying a high risk of damage to the surrounding normal nervous system tissue.

With an urgent need for new treatments, an international team of scientists focused on the Hippo signaling pathway, which normally controls organ size in human tissues and cells, but is dysregulated in multiple types of cancer.

An easier way to remove medical devices

MIT engineers have shown that medical devices made from aluminum can be disintegrated within the body by exposing them to gallium-indium, a liquid metal that seeps into the boundaries between the grains of the metal.
Credit: MIT based on figures courtesy of the researchers

By taking advantage of a phenomenon that leads to fractures in metal, MIT researchers have designed medical devices that could be used inside the body as stents, staples, or drug depots, then safely broken down on demand when they’re no longer needed.

The researchers showed that biomedical devices made from aluminum can be disintegrated by exposing them to a liquid metal known as eutectic gallium-indium (EGaIn). In practice, this might work by painting the liquid onto staples used to hold skin together, for example, or by administering EGaIn microparticles to patients.

Triggering the disintegration of such devices this way could eliminate the need for surgical or endoscopic procedures to remove them, the researchers say.

“It’s a really dramatic phenomenon that can be applied to several settings,” says Giovanni Traverso, the Karl van Tassel Career Development Assistant Professor of Mechanical Engineering at MIT and a gastroenterologist at Brigham and Women’s Hospital. “What this enables, potentially, is the ability to have systems that don’t require an intervention such as an endoscopy or surgical procedure for removal of devices.”

Traverso is the senior author of the study, which appears in Advanced Materials. Vivian Feig, an MIT postdoc, is the lead author of the paper.