Ultrafast beam-steering breakthrough at Sandia Labs

As a red beam of light is reflected in an arch, Prasad Iyer, right, and Igal Brener demonstrate optical hardware used for beam steering experiments at Sandia National Laboratories’ Center for Integrated Nanotechnologies.
Photo Credit: Craig Fritz

In a major breakthrough in the fields of nanophotonics and ultrafast optics, a Sandia National Laboratories research team has demonstrated the ability to dynamically steer light pulses from conventional, so-called incoherent light sources.

This ability to control light using a semiconductor device could allow low-power, relatively inexpensive sources like LEDs or flashlight bulbs to replace more powerful laser beams in new technologies such as holograms, remote sensing, self-driving cars and high-speed communication.

“What we’ve done is show that steering a beam of incoherent light can be done,” said Prasad Iyer, Sandia scientist and lead author of the research, which was reported in the current issue of the journal Nature Photonics. 

Incoherent light is emitted by many common sources, such as an old-fashioned incandescent light bulb or an LED bulb. This light is called incoherent since the photons are emitted with different wavelengths and in a random fashion. A beam of light from a laser, however, does not spread and diffuse because the photons have the same frequency and phase and is thus called coherent light.

Researchers Separate Cotton from Polyester in Blended Fabric

A cotton knit fabric dyed blue and washed 10 times to simulate worn garments is enzymatically degraded to a slurry of fine fibers and "blue glucose" syrup that are separated by filtration - both of these separated fractions have potential recycle value.
Photo Credit: Sonja Salmon.

In a new study, North Carolina State University researchers found they could separate blended cotton and polyester fabric using enzymes – nature’s tools for speeding chemical reactions. Ultimately, they hope their findings will lead to a more efficient way to recycle the fabric’s component materials, thereby reducing textile waste.

However, they also found the process needs more steps if the blended fabric was dyed or treated with chemicals that increase wrinkle resistance.

“We can separate all of the cotton out of a cotton-polyester blend, meaning now we have clean polyester that can be recycled,” said the study’s corresponding author Sonja Salmon, associate professor of textile engineering, chemistry and science at NC State. “In a landfill, the polyester is not going to degrade, and the cotton might take several months or more to break down. Using our method, we can separate the cotton from polyester in less than 48 hours.”

Researchers create breakthrough spintronics manufacturing process that could revolutionize the electronics industry

University of Minnesota researchers, along with a team at the National Institute of Standards and Technology (NIST), developed a breakthrough process for making spintronic devices that has the potential to become the new industry standard for semiconductors chips that are essential to computers, smartphones and many other electronics. The new process will allow for faster, more efficient spintronics devices that can be scaled down smaller than ever before. ​​

The paper is published in Advanced Functional Materials.

“We believe we’ve found a material and a device that will allow the semiconducting industry to move forward with more opportunities in spintronics that weren’t there before for memory and computing applications,” said Jian-Ping Wang, senior author of the paper and professor in the College of Science and Engineering. 

The semiconductor industry is constantly trying to develop smaller and smaller chips that can maximize energy efficiency, computing speed and data storage capacity in electronic devices. Spintronic devices, which leverage the spin of electrons rather than the electrical charge to store data, provide a promising and more efficient alternative to traditional transistor-based chips. These materials also have the potential to be non-volatile, meaning they require less power and can store memory and perform computing even after you remove their power source.

Underactive immune response may explain obesity link to COVID-19 severity

Intensive care unit at Addenbrooke's Hospital 
Photo Credit: Cambridge University Hospitals NHS Foundation Trust

Scientists at the Cambridge Institute of Therapeutic Immunology and Infectious Disease (CITIID) and Wellcome Sanger Institute showed that following SARS-CoV-2 infection, cells in the lining of the lungs, nasal cells, and immune cells in the blood show a blunted inflammatory response in obese patients, producing suboptimal levels of molecules needed to fight the infection.

Since the start of the pandemic, there have been almost 760 million confirmed cases of SARS-CoV-2 infection, with almost 6.9 million deaths. While some people have very mild – or even no – symptoms, others have much more severe symptoms, including acute respiratory distress syndrome requiring ventilator support.

One of the major risk factors for severe COVID-19 is obesity, which is defined as a body mass index (BMI) of over 30. More than 40% of US adults and 28% of adults in England are classed as obese.

While this link has been shown in numerous epidemiological studies, until now, it has not been clear why obesity should increase an individual’s risk of severe COVID-19. One possible explanation was thought to be that obesity is linked to inflammation: studies have shown that people who are obese already have higher levels of key molecules associated with inflammation in their blood. Could an overactive inflammatory response explain the connection?

Upgraded tumor model optimizes search for cancer therapies

Study co-authors (from left) Caleb Bashor, Antonios Mikos and Letitia Chim.
Photo Credit: Gustavo Raskosky/Rice University

Tumor cells won’t show their true selves in a petri dish, isolated from other cells.

To find out how they really behave, Rice University researchers developed an upgraded tumor model that houses osteosarcoma cells beside immune cells known as macrophages inside a three-dimensional structure engineered to mimic bone. Using the model, bioengineer Antonios Mikos and collaborators found that the body’s immune response can make tumor cells more resistant to chemotherapy.

The study, which is published in Biomaterials, sheds light on why some cancer drugs that appear to be good candidates in the lab do not perform as well as expected in actual patients. It underscores weaknesses in traditional tumor modeling and points the way toward more effective cancer therapies.

“Existing tumor models used to test drug performance do not mimic the actual environment in the human body closely enough,” Mikos said. “We are trying to create an environment for the experiment that is closer to what is happening in the organism of actual patients. Having such an environment will allow us to test multiple drugs in a time- and cost-effective way.”

Widespread species are gaining even more ground, new study shows

The cabezon Scorpaenichthys marmoratus
Photo Credit: Steve Lonhart (SIMoN / MBNMS)

Widespread animal and plant species benefit from human impacts on nature and can spread even further. In contrast, species with a small range retreat even further. This is shown in a new study by the German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig and the Martin Luther University Halle-Wittenberg (MLU), which was published in "Nature Communications". The team analyzed data from over 200 studies and was able to show that protected areas can mitigate some of the effects of biodiversity change and slow down the systematic decline of less common species.

Every living species on the planet has its own unique geographic range, with some species occurring over large parts of the globe, while others inhabiting only a few select areas. But does the range size of a species influence how it responds to human activities and changes in the number of sites it occupies over time?

A team led by researchers from iDiv and MLU set out to evaluate the connection between the size of a species’ range and the changes in their regional occupancy over time. To do so, the researchers used an extensive dataset of 238 studies that monitored plant and animal species assemblages from across many sites for 10-90 years. From these time series, they were able to determine which species were increasing in the numbers of sites they occupied through time, which were decreasing in their site occupancy, and which stayed the same. They then wanted to compare the trends of species to the size of their ranges to see if there was a connection. To determine the range sizes of nearly 19,000 species from across the tree-of-life that were identified in the time series, they used data from the Global Biodiversity Information Facility (GBIF), which includes data on the occurrences of species from across the world, including data collected from popular smartphone apps like iNaturalist and eBird.

Discovering the Unexplored: Synthesis and Analysis of a New Orthorhombic Sn3O4 Polymorph

Tuning the reaction conditions such as degree of filling and gas composition can have a major impact on the products obtained by hydrothermal synthesis obtained. This was clearly represented in the new Tokyo Tech study where they synthesized an unreported orthorhombic polymorph of Sn3O4 instead of conventional monoclinic phase by optimizing the conditions inside the hydrothermal reactor. The orthorhombic Sn3O4 has a narrower bandgap than the conventional one, thus making it useful as a visible-light active photocatalyst.

Oxides of tin (SnxOy) are found in many of modern technologies due to their versatile nature. The multivalent oxidation states of tin—Sn2+ and Sn4+—impart tin oxides with electroconductivity, photocatalysis, and various functional properties. For the photocatalysis application of tin oxides, a narrow bandgap for visible-light absorption is indispensable to utilize a wide range of solar energy. Hence, the discovery of new SnxOy could help improve the efficiency of many environmentally significant photocatalytic reactions like water splitting and CO2 reduction. While there are many theoretical and computational predictions of the new stable SnxOy, there still remains a need for experimental studies that can turn the predictions into reality.

Sculpting quantum materials for the electronics of the future

Artistic view. Curvature of the space fabric due to the superposition of spin and orbital states at the interface between lanthanum aluminate (LaAlO3) and strontium titanate (SrTiO3).
Illustration Credit: © Xavier Ravinet – UNIGE

An international team led by the UNIGE has developed a quantum material in which the fabric of space inhabited by electrons can be curved on-demand.

The development of new information and communication technologies poses new challenges to scientists and industry. Designing new quantum materials - whose exceptional properties stem from quantum physics - is the most promising way to meet these challenges. An international team led by the University of Geneva (UNIGE) and including researchers from the universities of Salerno, Utrecht and Delft, has designed a material in which the dynamics of electrons can be controlled by curving the fabric of space in which they evolve. These properties are of interest for next-generation electronic devices, including the optoelectronics of the future. These results can be found in the journal Nature Materials.

The telecommunications of the future will require new, extremely powerful electronic devices. These must be capable of processing electromagnetic signals at unprecedented speeds, in the picosecond range, i.e. one thousandth of a billionth of a second. This is unthinkable with current semiconductor materials, such as silicon, which is widely used in the electronic components of our telephones, computers and game consoles. To achieve this, scientists and industry are focusing on the design of new quantum materials.

First detection of neutrinos made at a particle collider

The FASER (Forward Search Experiment) detector in the tunnel of CERN’s Large Hadron Collider (LHC) in Geneva.
Photo Credit: © 2021-2023 CERN

Neutrinos are fundamental particles that played an important role in the early phase of the universe. They are key to learning more about the fundamental laws of nature, including how particles acquire mass and why there is more matter than antimatter. Despite being among the most abundant particles in the universe they are very difficult to detect because they pass through matter with almost no interaction. They are therefore often called “ghost particles”.

Neutrinos have been known for several decades and were very important for establishing the standard model of particle physics. But most neutrinos studied by physicists so far have been low-energy neutrinos. Previously, no neutrino produced at a particle collider had ever been detected by an experiment. Now, an international team including researchers from the Laboratory for High Energy Physics (LHEP) of the University of Bern has succeeded in doing just that. Using the FASER particle detector at CERN in Geneva, the team was able to detect very high energy neutrinos produced by brand a new source: CERN’s Large Hadron Collider (LHC). The international FASER collaboration announced this result on March 19 at the MORIOND EW conference in La Thuile, Italy.

Parasites alter likelihood of fish being caught by anglers

Itsuro Koizumi (second from left) and Ryota Hasegawa (first from right), authors of the paper, with Taro Matsuda of Setsunan University (center), and Masashiro Naka (first from left) and Chiharu Furusawa (second from right) of the Koizumi lab
Photo Credit: Itsuro Koizumi

Parasitic infections in salmonid fish can increase or decrease their vulnerability to angling, depending on their body condition.

Angling, a type of fishing, is a popular pastime across the world, and is known to be 40,000 years old. Angling usually takes place in natural bodies of water, which may have populations of wild fish, or be stocked with cultured fish. Fish caught by angling may either be consumed, or may be immediately released.

Parasites are very common in nature, found everywhere that their hosts are found. Parasites are known to alter the susceptibility of fish to predators. Angling can be considered predation of fish; however, there has been almost no in-depth research on how parasites affect the susceptibility of fish to angling.

Associate Professor Itsuro Koizumi at the Faculty of Environmental Earth Science, Hokkaido University, and graduate student Ryota Hasegawa have investigated how a mouth and gill parasite of the whitespotted char, a salmonid fish, affects its vulnerability to angling. Their findings were published in the journal The Science of Nature.