Innovative target design leads to surprising discovery in laser-plasma acceleration

Researchers studying laser-driven proton acceleration introduced an innovative, self-replenishing water sheet target to address the inefficiency of replacing targets after each laser pulse. The target had a surprising side effect, resulting in a naturally focused, more tightly aligned proton beam. 
Image Credit: Greg Stewart/SLAC National Accelerator Laboratory)

Scientists have developed a groundbreaking method for generating fast, bright proton beams using a high-repetition-rate laser-plasma accelerator. This work, published in Nature Communications, resolves several long-standing challenges and ushers this technology to the threshold of real-world applications – all thanks to a stream of water. 

“These exciting results pave the way for new applications of relativistic high-power lasers for applications in medicine, accelerator research, and inertial fusion,” said Siegfried Glenzer, professor of photon science and the director of the High Energy Density Science division at the Department of Energy's SLAC National Accelerator Laboratory. 

Celebrating 15 Years of Women and Girls in Science at KAUST

Photo Credit: Courtesy of King Abdullah University of Science and Technology

This year marks the 10th anniversary of the United Nation’s International Day of Women and Girls in Science. It also marks 15 years since King Abdullah University of Science and Technology (KAUST) was established as the first mixed-gender university in Saudi Arabia. Since then, KAUST has been a pioneer in championing women and girls in science in the Kingdom and across the Middle East. Today we celebrate all KAUST’s female graduates and scientists, many of whom have achieved remarkable success in their careers, such as becoming professors at leading universities worldwide, taking leadership roles in Saudi ministries and giga-projects, and founding tech companies that drive investment and create jobs in the Kingdom.     

KAUST's world-class research and education, supported by initiatives and projects like the KAUST Gifted Student Program (KGSP), the Ibn Rushd fellowship program and the KAUST Entrepreneurship Center, have been instrumental in this success. These programs nurture talent, foster innovation and empower women to excel in science and technology.   

Opening for a new type of drug for Alzheimer’s Disease

Kaj Blennow and Tohidul Islam.
Photo Credit: Johan Wingborg

A complementary drug to combat Alzheimer’s disease could target a specific part of the nerve cell protein tau. This is the finding of research from the University of Gothenburg, which also offers a better way to measure the effect of treatment among patients.

Researchers from the University of Gothenburg, together with colleagues from the University of Pittsburgh in the US, published their findings in the journal Nature Medicine.

The study provides insights into what happens during the earliest phase when the protein tau is transformed into thread-like strands (fibrils) in the nerve cells. This is one of the processes in Alzheimer’s disease and occurs alongside the formation of amyloid plaques. In healthy individuals, the protein tau stabilizes the tubular building blocks (microtubules) that make up the long projections of the nerve cells.

During the development of Alzheimer’s disease, tau undergoes pathological changes. First, tau forms small, soluble aggregates that are secreted from the nerve cells and are thought to be able to spread these changes to other nerve cells. The protein is then converted into larger, harmful, thread-like strands in the nerve cells.

How Botox enters our cells

Volodymyr M. Korkhov (left) and Richard Kammerer of the Center for Life Sciences at PSI have made important advances towards understanding how botulinum neurotoxin, botox for short, enters our nerve cells.
Photo Credit: © Paul Scherrer Institute PSI/Mahir Dzambegovic

Botulinum toxin A1, better known under the brand name Botox, is not only a popular cosmetic agent, but also a highly effective bacterial neurotoxin that – when carefully dosed – can be used as a drug. It blocks the transmission of signals from nerves to muscles: This can relax muscles under the skin, which in cosmetics is used to smooth facial features. It can also alleviate conditions that are caused by cramping muscles or faulty signals from nerves, such as spasticity, bladder weakness, or misalignment of the eyes. However, if the dose is too high, the use of Botox can be fatal due to paralysis of the respiratory muscles. This can happen as a result of bacterial meat poisoning and is called botulism.

To make the most effective use of botulinum toxin as a drug, to precisely control its action, and to expand the range of possible applications of the toxin, researchers want to better understand how the toxin enters nerve cells to exert its effect. Until now, little was known about this.  “This is mainly because we had no structural data on what the toxin looks like in its full-length form when binding to its nerve cell's receptor,” says Richard A. Kammerer of the PSI Center for Life Sciences. So far there had only been studies on the structure of individual domains of the toxin – that is, specific parts of its complex molecular structure – and on the structure of such domains in complex with the receptor or one of its domains. 

Collection of tiny antennas can amplify and control light polarized in any direction

New polarization-independent, highly resonant metasurfaces can precisely amplify and control light without requiring incoming light (top left) to be oriented and traveling in a certain direction.
Image Credit: Bo Zhao

Antennas receive and transmit electromagnetic waves, delivering information to our radios, televisions, cell phones and more. Researchers in the McKelvey School of Engineering at Washington University in St. Louis imagines a future where antennas reshape even more applications.

Their new metasurfaces, ultra-thin materials made of tiny nanoantennas that can both amplify and control light in very precise ways, could replace conventional refractive surfaces from eyeglasses to smartphone lenses and improve dynamic applications such as augmented reality/virtual reality and LiDAR.

While metasurfaces can manipulate light very precisely and efficiently, enabling powerful optical devices, they often suffer from a major limitation: Metasurfaces are highly sensitive to the polarization of light, meaning they can only interact with light that is oriented and traveling in a certain direction. While this is useful in polarized sunglasses that block glare and in other communications and imaging technologies, requiring a specific polarization dramatically reduces the flexibility and applicability of metasurfaces.

Influenza A viruses adapt shape in response to environmental pressures

Colorized transmission electron micrograph of influenza A virus particles, colorized red and gold, isolated from a patient sample and then propagated in cell culture. Influenza A can infect both humans and animals, including birds and pigs. More specifically, this image features the H3N2 influenza strain, isolated from a patient in Victoria, Australia, in 1975. Notable for forming both spheric
Image Credit: National Institute of Allergy and Infectious Diseases

Influenza A virus particles strategically adapt their shape—to become either spheres or larger filaments—to favor their ability to infect cells depending on environmental conditions, according to a new study from National Institutes of Health (NIH) scientists. This previously unrecognized response could help explain how influenza A and other viruses persist in populations, evade immune responses, and acquire adaptive mutations, the researchers explain in a new study published in Nature Microbiology.

The study, led by intramural researchers at NIH’s National Institute of Allergy and Infectious Diseases (NIAID), was designed to determine why many influenza A virus particles exist as filaments. The filament shape requires more energy to form than a sphere, they state, and its abundance has been previously unexplained. To find the answer, they developed a way to observe and measure real-time influenza A virus structure during formation.

Study reveals reasons for misdiagnosis of frontotemporal dementia

Researchers have discovered patterns in the misdiagnosis of frontotemporal dementia
Photo Credit: Anna Shvets

University of Queensland researchers discovered that nearly 70 per cent of suspected frontotemporal dementia patients ultimately did not have the disease, in a study aimed at identifying factors that contribute to misdiagnosis of this notoriously difficult to diagnose disorder.

Psychiatrist Dr Joshua Flavell, working with cognitive neurologist Professor Peter Nestor at the Mater Hospital Memory and Cognitive Disorders clinic and UQ’s Queensland Brain Institute, analyzed data from 100 patients suspected of having frontotemporal dementia who had been referred by specialist physicians like neurologists, psychiatrists or geriatricians.

“Of the 100 patients, 34 were true-positive, and 66 were false-positive for frontotemporal dementia,” Dr Flavell said.

“We found that misinterpretation of brain scans, particularly nuclear imaging, led to 32 patients being incorrectly diagnosed.

How Does the Brain Differentiate New Stimuli from Old Ones?

The illustration represents how sounds are encoded in the cerebral cortex, with neurons (at right) using "echoing" activity to track auditory stimuli to change and improve its predictions of the future.
Illustration Credit: Yuriy Shymkiv

The cerebral cortex is the largest part of a mammal’s brain, and by some measures the most important. In humans in particular, it’s where most things happen—like perception, thinking, memory storage, and decision-making. One current hypothesis suggests that the cortex’s primary role is to predict what’s going to happen in the future by identifying and encoding new information it receives from the outside world and comparing it with what was expected to occur.

A new study published today in the journal Neuron takes a big step toward proving that hypothesis. The paper’s lead author is Yuriy Shymkiv, a postdoctoral fellow in the lab of Professor Rafael Yuste.

“We found that the cortex acts like a memory machine, encoding new experiences, and predicting the very near future,” Shymkiv said.

Purdue biochemists discover self-repair function in key photosynthetic protein complex

Sujith Puthiyaveetil and Steve McKenzie look at a plant thylakoid in a lab at the biochemistry building at Purdue University.
Photo Credit: Purdue Agricultural Communications/Joshua Clark

Cyanobacteria began contributing oxygen to Earth’s mostly noxious atmosphere more than 2 billion years ago. The photosystem II protein complex now shared by various lineages of cyanobacteria, algae and land plants has served as a major site of oxygen production throughout the history of life on Earth ever since.

Ironically, receiving too much light can damage photosystem II and erode the photosynthetic efficiency of plants. Purdue University biochemists Steven McKenzie and Sujith Puthiyaveetil have gleaned new, long-hidden details about how photosystem II repairs itself. McKenzie and Puthiyaveetil’s findings have been published in the journal Plant Communications.

“The photosystem II splits water and extracts electrons and protons, leaving oxygen as a by-product. Photosystem II thereby powers life on Earth,” said Puthiyaveetil, associate professor of biochemistry. Even so, “it’s still fairly poorly understood how these huge protein complexes that use light energy to produce oxygen are able to be repaired and maintained so efficiently across different lineages of plants, algae and cyanobacteria.”

Rice scientists create tiny, water-based reactors for green chemistry

Researchers at Rice, including Ying Chen and Angel Martí, have developed a new method for performing chemical reactions using water instead of toxic solvents.
Photo Credit: Jeff Fitlow/Rice University.

Researchers at Rice University have developed a new method for performing chemical reactions using water instead of toxic solvents. The scientists created microscopic reactors capable of driving light-powered chemical processes by designing metal complex surfactants (MeCSs) that self-assemble into nanoscale spheres called micelles. This innovation could drastically reduce pollution in industries including pharmaceuticals and materials science, where harmful organic solvents are often necessary.

The new micellar technology represents a step forward in sustainable chemistry. These self-assembled micelles form in water, where their hydrophobic cores provide a unique environment for reactions, even with materials that are typically insoluble in water. The research team led by Angel Martí, professor and chair of chemistry at Rice, demonstrated that this system can efficiently perform photocatalytic reactions while eliminating the need for hazardous substances. The study was published in Chemical Science Feb. 10.

“Our findings show how powerful molecular design can be in tackling chemical sustainability challenges while maintaining high chemical performance,” Martí said. “We’ve created a tool that could transform how chemical reactions are performed, reducing environmental harm while increasing efficiency.”