Menu

Blog

Page 1407

Jan 31, 2024

A Trojan approach to guide and trap light beams via Lagrange points

Posted by in categories: physics, space

Reliably guiding and capturing optical waves is central to the functioning of various contemporary technologies, including communication and information processing systems. The most conventional approach to guide light waves leverages the total internal reflection of optical fibers and other similar structures, yet recently physicists have been exploring the potential of techniques based on other physical mechanisms.

Researchers at University of Southern California recently devised a highly innovative approach for trapping light. This method, introduced in Nature Physics, exploits the exotic properties of Lagrange points, the same equilibrium points that govern the orbits of primordial celestial bodies, such as so-called Trojan asteroids in the sun-Jupiter system.

“The discovery of Lagrange points, which happens to be pivotal in this research, can be traced back to the early work of Leonhard Euler and Joseph-Louis Lagrange, which found that at these locations, the exerted by two large bodies can be precisely counterbalanced by centrifugal forces,” Mercedeh Khajavikhan and Demetrios N. Christodoulides, co-authors of the paper, told Phys.org.

Jan 31, 2024

Decay of sunspot pair elucidates properties of nearby moving magnetic features

Posted by in categories: evolution, satellites

Scientists studying sunspots have found important clues about magnetic features in their decay that will help understand the evolution and real origin of these mysterious magnetic phenomena. The findings are published in The Astrophysical Journal.

Understanding is crucial to understanding the , the approximately 11-year periodic change that changes the sun’s energy output and the frequency and intensity of flares it sends into space that can negatively influence satellites and electrical networks on Earth. (The solar “cycle” can range from eight to 14 years in length.)

Sunspots look rather simple from a distance but are complex areas where light from the sun is trapped by twisted magnetic fields. They are temporary regions of reduced temperature that appear as dark spots on the surface of the sun, where constricted suppresses convection that brings the inner heat of the sun to the surface. A sunspot is about the size of the Earth, and they often come in pairs.

Jan 31, 2024

A breath of fresh air in plasmonic catalysis: Black gold and solar light’s renaissance

Posted by in category: futurism

Prof. Polshettiwar’s group at Tata Institute of Fundamental Research (TIFR), Mumbai has developed a novel “plasmonic reduction catalyst stable in air,” defying the common instability of reduction catalysts in the presence of air. The catalyst merges platinum-doped ruthenium clusters, with “plasmonic black gold.” This black gold efficiently harvests visible light and generates numerous hot spots due to plasmonic coupling, enhancing its catalytic performance.

The team describes their work in a paper published in the journal Nature Communications.

What sets this catalyst apart is its remarkable performance in the semi-hydrogenation of acetylene, an important industrial process. In the presence of excess ethene, and using only illumination without any external heating, the catalyst achieved an ethene production rate of 320 mmol g−1 h−1 with around 90% selectivity. This efficiency surpasses all known plasmonic and traditional thermal catalysts.

Jan 31, 2024

Scientists build high power cladding-pumped Raman fiber laser at 1.2 μm waveband

Posted by in category: biotech/medical

Laser sources operating at the 1.2 μm wavelength band have some unique applications in photodynamic therapy, biomedical diagnosis and oxygen sensing. Additionally, they can be adopted as pump sources for mid-infrared optical parametric generation as well as visible light generation by frequency doubling.

Laser generation at 1.2 μm waveband has been achieved with different solid-state lasers including semiconductor lasers, diamond Raman lasers, and fiber lasers. Among these three types, the fiber laser thanks to its simple structure, good beam quality, and operation flexibility, is a great choice for 1.2 μm waveband laser generation.

Researchers led by Prof. Pu Zhou at National University of Defense Technology (NUDT), China, are interested in a fiber laser at 1.2 μm waveband. Current high power fiber lasers are mostly ytterbium-doped fiber lasers at 1 μm waveband, and the maximum output at 1.2 μm waveband is limited at 10-watt level.

Jan 31, 2024

Scientists pinpoint growth of brain’s cerebellum as key to evolution of bird flight

Posted by in categories: biotech/medical, evolution, neuroscience

Evolutionary biologists at Johns Hopkins Medicine report they have combined PET scans of modern pigeons along with studies of dinosaur fossils to help answer an enduring question in biology: How did the brains of birds evolve to enable them to fly?

The answer, they say, appears to be an adaptive increase in the size of the cerebellum in some fossil vertebrates. The cerebellum is a brain region responsible for movement and motor control.

The research findings are published in the Jan. 31 issue of the Proceedings of the Royal Society B.

Jan 31, 2024

Slow Walking Character Animation Made With Blender & Houdini

Posted by in category: futurism

Sun Somei continues sharing behind-the-scenes sneak peeks at their new commercial.

Jan 31, 2024

The CEO behind a Chinese startup says its AR glasses will blow Apple’s Vision Pro out of the water. Here’s why

Posted by in category: augmented reality

Nice!


XReal’s AR glasses aim to be an affordable alternative to Apple’s pricier Vision Pro, CEO Chi Xu told Bloomberg.

Jan 30, 2024

Cervical cancer is preventable, yet rising number of women in poor regions are getting it

Posted by in category: biotech/medical

The findings aren’t as simple as increased detection, seen with increases in late-stage cancer for white women and mortality among Black women.

Jan 30, 2024

YouTube: This CU Cancer Center’s Education Working Group Lunch and Learn features Stacy Grolnic

Posted by in categories: biotech/medical, education

https://www.youtube.com/watch?si\u003dGp5uRChnBm-OuMqT\u0026v\u003d1Kt58VJCt5c\u0026feature\u003dyoutu.be

RN, BSN, breelyn wilky, MD, denise castillo, tessa mcspadden, stephanie hill, MA, CCRP, and tiffany cull.

Jan 30, 2024

Forecasting Floods: Implications of Back-to-Back Atmospheric River Events

Posted by in categories: computing, economics, information science

How can back-to-back atmospheric rivers impact the economy? This is what a recent study published in Science Advances hopes to address as a team of researchers led by Stanford University investigates the economic toll of back-to-back atmospheric rivers compared to single events. This study holds the potential to help scientists, the public, and city planners better prepare for atmospheric rivers, as they can cause widespread flooding in short periods of time.

For the study, the researchers analyzed data from the Modern-Era Retrospective Analysis for Research and Applications, version 2, (MERRA-2) between 1981 and 2021 and computer algorithms to ascertain the economic impact of atmospheric rivers throughout California. The goal was to ascertain how much worse back-to-back atmospheric rivers were compared to single events. The study’s findings discovered that back-to-back atmospheric rivers caused three times greater economic damage than single events, which is also higher when the first atmospheric river exhibits greater strength.

“Our work really shows that we need to consider the likelihood for multiple, back-to-back events for predicting damages, because damage from multiple events could be far worse than from one event alone,” said Dr. Katy Serafin, who is a coastal scientists and assistant professor in the Department of Geography at the University of Florida and a co-author on the study.