Toggle light / dark theme

Get the latest international news and world events from around the world.

Log in for authorized contributors

From engineered fungal molecules to drug leads, chem-bio hybrid synthesis enables antiparasitic drug discovery

Amebiasis is a parasitic disease caused by the microscopic protozoan Entamoeba histolytica. Infection occurs through the ingestion of cysts from contaminated water or food. Worldwide, approximately 50 million symptomatic cases are estimated annually, mainly in tropical and subtropical regions.

Fumagillin, a fungal natural product, has been studied for decades as a potential antiparasitic drug, but its more potent relative, ovalicin, was never developed. Now, a study published in the Journal of the American Chemical Society reveals why: although ovalicin is highly active against amebiasis, liver enzymes rapidly break it down in the body. Researchers used a chem-bio hybrid approach to turn that insight into metabolically stable drug candidates that worked in animal models of amebiasis, including liver infection with abscess formation.

The research team, led by scientists from the Graduate School of Bioagricultural Sciences at Nagoya University, identified the liver cytochrome P450 enzymes responsible for ovalicin breakdown, with CYP 2B1 and CYP 2C6 emerging as the main drivers. Blocking these enzymes with a chemical inhibitor significantly prolonged ovalicin survival, providing strong evidence that rapid liver metabolism limits its effectiveness.

Fieldoscopy reveals femtosecond optical switching in 15 nm indium tin oxide nanocrystals

Just as an antenna interacts with radio waves, light interacts with metallic nanostructures. Therefore, understanding how a structure influences field oscillations provides valuable insights into the structure’s physical properties. An international research team, including scientists from the Max Planck Institute for the Science of Light (MPL), is investigating the changes in field oscillations that occur when light interacts with indium tin oxide (ITO) nanocrystals. This will deepen our understanding of how the interaction between light and these nanocrystals depends on time.

Precise and high-speed control of light is crucial to optical communication. It opens up the possibility to transmit data more quickly and efficiently in the future. Optical switches, which can activate or deactivate light pulses selectively, are a key component in achieving this.

To ensure optimal performance and prevent delays caused by switching times, the switches must respond very fast. Ideally, they also have the highest possible modulation depth. This refers to the difference in brightness between the light transmitted in the “on” and “off” states. Additionally, a suitable switch exhibits the same predictable behavior each time it is used.

Novel measurement confirms a 50-year-old prediction: Dark points are faster than light

A research group from the Technion-Israel Institute of Technology reports in Nature an unprecedented achievement in electron microscopy: the direct measurement of “dark points” within light waves. By doing so, the researchers were able to confirm a prediction from the 1970s that the speed of these points exceeds the speed of light.

The “dark points” measured by the group are essentially tiny “holes” in the wave structure. Known as vortices, the holes are a common phenomenon in nature: We encounter them in ocean waves, in air currents, and even in coffee when we stir it or pour it into the sink. As early as the 1970s, a surprising theoretical prediction was proposed: Vortices may move faster than the wave in which they are formed. As strange as it sounds—imagine a vortex in a river overtaking the flow of water in which it exists—the phenomenon is real. Until now, this was based on theory. The research team’s achievement has now confirmed it experimentally.

Hubble detects first-ever spin reversal of tiny comet

Astronomers using NASA’s Hubble Space Telescope have found evidence that the spinning of a small comet slowed and then reversed its direction of rotation, offering a dramatic example of how volatile activity can affect the spin and physical evolution of small bodies in the solar system. This is the first time researchers have observed evidence of a comet reversing its spin.

The object, comet 41P/Tuttle-Giacobini-Kresák, or 41P for short, likely originated in the Kuiper Belt, and was flung into its current trajectory by Jupiter’s gravity, now visiting the inner solar system every 5.4 years.

After its 2017 close passage around the sun, scientists found that comet 41P experienced a dramatic slowdown in its rotation. Data from NASA’s Neil Gehrels Swift Observatory in May 2017 showed the object was spinning three times more slowly than it had in March 2017 when it was observed by the Discovery Channel Telescope at Lowell Observatory in Arizona.

Quantum experiment shows events may have no fixed order

For the first time, a team of physicists in Austria has carried out an experiment that appears to verify the principle of indefinite causal order: an idea that suggests that timelines of events can exist in multiple orders at the same time. Led by Carla Richter at the Vienna Center for Quantum Science and Technology, the researchers hope their result could finally allow physicists to verify a key prediction of quantum theory. The results have been published in PRX Quantum.

The basic principle of cause and effect underpins everything that happens in the classical world: for an event to occur, it must be triggered by another event in its past. Yet in the quantum world, physicists have long suspected that these rules may not always apply.

Just as quantum particles can exist in superpositions of multiple states which collapse to a single outcome when measured, indefinite causal order suggests something similar may apply to entire sequences of events. Until a measurement is made, multiple orders of cause and effect can exist in superposition.

Tiny LED design could power next-generation technology

From 3D movie screens to augmented-reality devices, many modern technologies rely on our ability to manipulate light. Doing so in a cost-effective and efficient way, however, is often a formidable task. In an article published in Optics Letters, researchers from the University of Osaka announced a new light-emitting diode (LED) design that may help shrink complex optical systems into much smaller devices. The LED produces circularly polarized light using a built-in nanostructured surface, eliminating the need for bulky external optical components.

Circularly polarized light, whose electric field rotates like a corkscrew as it travels, is essential for technologies such as 3D displays, advanced imaging systems, and quantum communication tools. Traditionally, generating this kind of light requires optical components such as polarizers and special plates that modify the light’s phase. However, these components make devices larger, more complex, and harder to integrate.

“Our goal is to simplify the way circularly polarized light is produced,” says corresponding author Shuhei Ichikawa. “By integrating polarization control directly into the LED with a specially designed metasurface, we remove the need for additional optical components.”

Experimental evidence shows how photons spread across multiple paths in an interferometer

The nature of quantum particles has long puzzled scientists. While single-particle interference suggests that a photon can behave like a spread-out wave, a whole photon is only ever detected in one specific place. Traditional interpretations of quantum mechanics often address this by suggesting the particle is in a superposition of being here and there at the same time. However, this tells us only where the particle is when it is measured, not where the particle physically is when no detector is present.

A research team led by Hiroshima University, led by Holger F. Hofmann, professor at the Graduate School of Advanced Science and Engineering, has now developed a method to measure this delocalization without disturbing the photon’s wave-like path.

In a study published in the New Journal of Physics, the researchers applied a modification of the well-established method of “weak measurements” to a two-path interferometer. As the photon traveled, they applied a tiny rotation by a positive angle in one path and a negative angle in the other. If the two paths interfere in the output, the average rotation angle is always zero. However, this is only a statistical average.

New synthetic origin of replication lets multiple plasmids coexist in one bacterial cell

“If it ain’t broke, don’t fix it,” goes the old adage, which Rice University professor James Chappell completely ignored in a recent Nature Communications publication. In the study, Chappell describes an innovation in plasmids, circular pieces of DNA that have been a workhorse of molecular biology research since the 1970s.

“For decades, we’ve been designing experiments around two major limitations of plasmids: fixed copy numbers and incompatibility,” said Chappell, the corresponding author on the study. “While functional, such workarounds are clunky. We created a synthetic version of a part of the plasmid called the origin of replication that allows us to modify the plasmid instead of modifying the experiment.”

Plasmids are typically put into bacterial cells, where they use the cell’s machinery to build proteins and create copies of themselves. Each plasmid generates tiny pieces of a stop signal, called a negative regulator, which binds to the origin of replication (ORI).

Quantum computer accurately simulates real magnetic materials, reproducing national laboratory data

Studying and designing novel materials is a central application of quantum mechanics. Chemists, materials scientists, and physicists focus on subtle interactions in quantum materials and to uncover them they rely on sophisticated computational and experimental techniques. Computer simulations that connect microscopic quantum interactions to measurable material properties complement experimental data to connect structure to function—but classical computers can struggle to simulate those properties. Fortunately, scientists today have a new tool in their toolbox: quantum computers.

In new preprint, a team of researchers from Oak Ridge National Lab’s (ORNL’s) Quantum Science Center (QSC), Purdue University, Los Alamos Laboratory, the University of Illinois at Urbana-Champaign, the University of Tennessee, and IBM used quantum simulation to compute the energy-momentum spectrum of a well-studied magnetic material, KCuF3, showing strong agreement with the spectra measured via neutron scattering. The research is published on the arXiv preprint server.

The quantum simulations employed the IBM Quantum Heron processor, while the experimental data was acquired from neutron sources at the Spallation Neutron Source (SNS) at ORNL and at the Rutherford Appleton Laboratory in the United Kingdom. This work serves as another realization of Richard Feynman’s vision: the use of a well-controlled, programmable quantum system to simulate the properties of a quantum system of interest.

Unlocking scalable entanglement will enable next-generation quantum computing

Quantum computing promises to transform our world in rapid, radical and revolutionary ways: solving in seconds problems that would take classical computers years, accelerating the discovery of new medicines, creating sustainable materials, optimizing complex systems, and strengthening cybersecurity. It does so using qubits, the quantum counterparts of classical bits, which can occupy multiple states simultaneously and enable a fundamentally new kind of computation.

For example, imagine 1,000 trucks need to arrive at 10,000 different locations, each, in different parts of the country. A traditional computation model would examine each of the 10 million possible routes one by one to evaluate their efficacy, but a quantum model would be able to evaluate all those millions of different routes instantaneously.

At the same time, quantum sensing is opening new frontiers in precision measurement, enabling technologies such as ultra-sensitive medical imaging and navigation systems that can detect minute changes in gravity or magnetic fields, capabilities that could allow doctors to identify diseases earlier or help vehicles navigate without GPS. UCF researchers believe the science of light, photonics, may hold the key to unlocking quantum computing’s true potential.

/* */