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Elusive tularemia proteins reveal possible treatment target in rare tick-borne disease

Tularemia is a rare but highly infectious disease caused by Francisella tularensis, a bacterium that can evade immune defenses. Symptoms of infection can include fever, swollen lymph nodes, and—in some cases—pneumonia. What makes the pathogen especially concerning is how little it takes to cause infection—fewer than 10 bacterial cells can be enough. Scientists at Arizona State University have taken a key step toward understanding how this bacterium survives inside the human body. For the first time, the team has isolated and studied a set of proteins that play a central role in infection, revealing a potential weakness that could eventually be targeted with new treatments. The study is published in the journal Biochimica et Biophysica Acta (BBA)–Biomembranes.

The proteins sit within the bacterium’s inner membrane and appear to work together, forming small assemblies that help it persist inside host cells. Until now, researchers had been unable to produce and stabilize these proteins in the lab, leaving a critical part of the pathogen’s biology unexplored. By developing a method to extract and analyze them, the team has opened the door to more detailed structural studies and eventually, new ways to disrupt the infection process.

The work builds on earlier studies of individual proteins, but advances the research by capturing a group of proteins that function together as a system—one that is essential for infection but had remained inaccessible.

Soundwaves settle debate about elusive quantum particle

It was a head-spinning discovery. In 2018, researchers in Japan claimed to find concrete evidence of an elusive particle, a Majorana fermion, in a quantum spin liquid called ruthenium trichloride. Majoranas are highly sought-after by quantum materials scientists because when a pair are localized, or trapped, they can securely encode information and form a stable qubit—the building block of quantum computing.

Some researchers heralded the finding and used it to launch their own studies, while others believed the breakthrough—which was made by measuring what’s called the thermal Hall effect—was actually a mirage caused by defects in the material sample.

Cornell researchers have now waded into the debate and their findings, published in Nature, show both camps were wrong. By measuring the movement of sound waves rather than the flow of heat, the team discovered the thermal Hall effect was caused by rotating lattice vibrations called chiral phonons.

Light-powered propulsion expands space exploration possibilities

Reaching the nearest star system, Alpha Centauri, would take hundreds of thousands of years using current rocket propulsion technology. Researchers in the J. Mike Walker ‘66 Department of Mechanical Engineering at Texas A&M University have demonstrated a new approach to light-driven motion, showing that lasers can be used to lift and steer objects in multiple directions without physical contact. This breakthrough may one day enable travel to Alpha Centauri within roughly 20 years.

Dr. Shoufeng Lan, assistant professor and director of the Lab for Advanced Nanophotonics, and his team published the work, “Optical propulsion and levitation of metajets,” in Newton. The study introduces micron-scale devices, termed “metajets,” that generate controlled motion when illuminated by laser light.

These metajets are composed of metasurfaces —ultrathin materials engineered with tiny patterns that enable scientists to control how light behaves, much like shaping a lens, but on a much smaller and more precise scale. By carefully designing these structures, the research team controlled how light transfers momentum to an object, enabling it to move.

Why does life prefer one ‘hand’ over the other? New study points to electron spin

A team of scientists has identified a new physical mechanism that could help explain one of the most persistent mysteries in science: why life consistently uses one “handed” version of its molecules and not the other. In a new study led by Prof. Yossi Paltiel of the Center for Nanoscience and Nanotechnology at Hebrew University and Prof. Ron Naaman of the Weizmann Institute, researchers show that electron spin, a fundamental quantum property, can cause mirror-image molecules to behave differently during dynamic processes, even though they are otherwise identical. The work appears in Science Advances.

Many molecules essential to life come in two mirror-image forms, known as enantiomers. Chemically, these forms are nearly indistinguishable. Yet in living systems, only one version is typically used: amino acids are almost exclusively one type, while sugars follow the opposite pattern.

This phenomenon, known as homochirality, has puzzled scientists for more than a century. Existing explanations have struggled to account for why one specific version was selected globally.

ATLAS sets record limits on Higgs boson’s self-interaction

One of the biggest open questions in particle physics today is how the Higgs boson interacts with itself. This “self-coupling” could help explain the evolution of the early universe and the mechanism that gives mass to elementary particles. To try to shed light on this fundamental interaction, the ATLAS Collaboration has recently studied one of the “golden” decay channels of a pair of Higgs bosons, where one Higgs boson decays into two photons and the other into a pair of bottom quarks.

The Universe Is Expanding Too Fast and Scientists Can’t Explain Why

The most precise measurement yet shows the Universe is expanding faster than expected, deepening the Hubble tension. The result hints that something may be missing from our current understanding of the cosmos.

An international team of astronomers has produced one of the most accurate measurements so far of how quickly the nearby Universe is expanding. Rather than settling a long-standing debate, the new result intensifies one of the biggest unresolved problems in cosmology. The collaboration includes John Blakeslee of NSF NOIRLab, which is funded by the U.S. National Science Foundation, and draws on data from telescopes across two NSF NOIRLab Programs.

Two competing ways to measure cosmic expansion.

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