Новости за 27.12.2021

An innovative approach could turn nanoparticles into simple reservoirs for storing hydrogen. The highly volatile gas is considered a promising energy carrier for the future, which could provide climate-friendly fuels for airplanes, ships and trucks, for example, as well as allowing climate-friendly steel and cement production—depending on how the hydrogen gas is generated. However, storing hydrogen is costly: Either the gas has to be kept in pressurized tanks, at up to 700 bar, or it must be liquified... Читать дальше...

Life is teeming nearly everywhere in the oceans, except in certain pockets where oxygen naturally plummets and waters become unlivable for most aerobic organisms. These desolate pools are "oxygen-deficient zones," or ODZs. And though they make up less than 1 percent of the ocean's total volume, they are a significant source of nitrous oxide, a potent greenhouse gas. Their boundaries can also limit the extent of fisheries and marine ecosystems.

Sediments in which archaeological finds are embedded have long been regarded by most archaeologists as unimportant by-products of excavations. However, in recent years it has been shown that sediments can contain ancient biomolecules, including DNA. "The retrieval of ancient human and faunal DNA from sediments offers exciting new opportunities to investigate the geographical and temporal distribution of ancient humans and other organisms at sites where their skeletal remains are rare or absent," says Matthias Meyer... Читать дальше...

Subduction zones, where a slab of oceanic plate is pushed beneath another tectonic plate down into the mantle, cause the world's largest and most destructive earthquakes. Reconstructing the geometry and stress conditions of the subducted slabs at subduction zones is crucial to understanding and preparing for major earthquakes. However, the tremendous depths of these slabs make this challenging—seismologists rely mainly on the rare windows into these deeply buried slabs provided by the infrequent but strong earthquakes... Читать дальше...

The concept of gamification is increasingly gaining popularity—tourists frequently traveling overseas earn frequent flier points from their preferred airline; customers purchasing apparel from their favorite fashion outlet accumulate customer loyalty points. Both of these examples involve gamification: The inclusion of game-like features (points) to increase the odds of a desired outcome (a future purchase). Although gamification has been used extensively by marketing professionals to entice customers... Читать дальше...

Strong, lightweight and biocompatible foams glow in the dark when ultraviolet light is shone on them, RIKEN chemists have discovered. This phosphorescence could have diverse applications, such as imaging biological samples under the microscope.

On 17 and 18 December 2021, a few hundred dead knots (Calidris canutus) were discovered on Schiermonnikoog and in Oost-Groningen. At the behest of the Netherlands Food and Consumer Product Safety Authority, Wageningen Bioveterinary Research (WBVR) examined a few dead knots, an oystercatcher, and a curlew who were found in the same location. The avian influenza H5N1 virus was detected in the birds examined. It is suspected to be the highly pathogenic variant, but this is under further investigation.

In a study published in Physical Review-Physics Education Research, a research team led by Academician Guo Guangcan from the University of Science and Technology of China (USTC) of the Chinese Academy of Sciences has successfully constructed a theoretical framework of Activation-Construction-Execution-Reflection as well as a thinking mechanism model based on Overgeneralization to help students solve bound and scattering state problems in quantum mechanics education.

Earth's ecosystems and human activities are threatened by a broad spectrum of hazards threatening ground infrastructures, space systems and space flight: Solar activity, earthquakes, atmospheric and climatic disturbances, changes in the geomagnetic field, fluctuations of the global electric circuit. These hazards leave distinguishable characteristic imprints on a critical layer of geospace: The Earth's ionosphere, middle and upper atmosphere (IMUA).

The pioneers of holography (Gabor, Leith, Upatnieks, and Denisyuk) predicted very early that the ultimate 3D display will be based on this technique. This conviction was rooted in the fact that holography is the only approach that can render all optical cues interpreted by the human visual system. Holographic 3D displays have been a dream chased after for many years, facing challenges on all fronts: Computation, transmission, and rendering. With numbers such as 6.6 × 1015 flops required for calculations... Читать дальше...

Blood flow velocity is an important parameter reflecting vascular function. Abnormal vascular function is closely related to the occurrence and development of many diseases, such as diabetes, arteriosclerosis, thrombosis and so on. Therefore, the monitoring of flow velocity is not only an important research target, but also an important clinical indicator.

The ability to quantify optical properties (i.e., absorption and scattering) of strongly turbid media has major impacts on the characterization of biological tissues, fluid fields, and many others. However, the task of quantitative imaging of optical properties for strongly turbid media is intrinsically challenging, as photon scattering hinders direct measurement over length scales larger than the mean free path. Few current imaging technologies can quantify absorption and scattering properties of... Читать дальше...

Developing low-cost and highly efficient electrocatalysts for oxygen reduction reaction (ORR) to replace commercial Pt/C has always been desired to greatly reduce the cost of polymer electrolyte membrane (PEM) fuel cells. The parameter of half-wave potential (E1/2) obtained from linear-sweep voltammetry (LSV) in O2-saturated acid/alkaline medium on a rotating disk electrode (RDE) is commonly used for characterizing the ORR performance of all kinds of new electrocatalysts. With higher value of E1/2, the ORR performance becomes better. Читать дальше...

Heavy metals have a reputation for being dangerous, but some are essential nutrients that you can't live without. In this week's episode of Reactions, we explore why:

By analyzing the acquisition-conservation tradeoff in root systems among different plants, ecologists have put forward the root economics spectrum (RES) hypothesis. Some plant species have finer and cost-effective absorptive roots that contribute to rapid nutrient uptake but have shorter lifespans, whereas others have thicker and less cost-effective absorptive roots marked by slower nutrient acquisition but longer lifespans. The RES hypothesis reflects the correlations among different root traits... Читать дальше...

Studies of the genomic DNA compaction in the cell nucleus and dynamic reorganization during physiologic processes or disease development in live cell environments are exceedingly challenging. This complexity stems from a high degree of compaction required to accommodate ~2 meters of genomic DNA within the cell nucleus, which typically is 5 to 10 micrometers in diameter. In addition, the chromatin compaction density is not static, but fluctuates over time accommodating for gene activities. Meanwhile... Читать дальше...

With the demand in real-time monitoring of endoplasmic variations and rapid detection of extracellular signals, a great number of approaches to bioimaging have been developed. The past few decades have witnessed a dramatic progress in optical imaging, especially with the emerging of microsphere-assisted techniques that have the excellent ability of signal collection and enable real-time and super-resolution imaging with conventional optical microscopic systems. However, as most of the microspheres... Читать дальше...

Comprised of judiciously engineered microscopic photonic structures with subwavelength features, the concepts of metasurface and metamaterials have proven fruitful results in the realm of meta-optics. Previous research attentions are mainly devoted to applying meta-structures to tailor light in free space and develop relevant devices and applications. However, recent research is revealing the prominent potential of leveraging subwavelength meta-structured waveguides to enable exotic waveguiding phenomena... Читать дальше...

Optical interference is not only a fundamental phenomenon that has enabled new theories of light to be derived, but it has also been used in interferometry for the measurement of small displacements, refractive index changes, and surface irregularities. The Michelson interferometer is a commonly used interferometer, by which the equal-inclination and equal-thickness interference fringes of light can be easily observed. Historically, this interferometer has been used in many famous physical experiments... Читать дальше...

Cylindrical vector beam (CVB) multiplexing has emerged as a powerful technique to boost signal channels. Coupling and separating CVBs are two pivotal elements in CVB multiplexing communication. Although off-axis control technologies such as miniature Dammann vortex gratings have been investigated to couple and separate light beams, it is usually limited to light beams with homogeneous polarization due to its phase-only grating structure. For CVBs with inhomogeneous polarization, a gradient phase... Читать дальше...

Reporting in Scientific Reports, an international research team of researchers from Kyoto University and University of Strasbourg has used drones to investigate the "multilevel societal structure" of the feral horses in Serra D'Arga, Portugal.

NUS chemists have developed a new "catalyst control" blueprint to overcome a longstanding challenge in the site-selective dicarbofunctionalization of unactivated alkenes, by enabling the reaction to proceed in the absence of directing or activating groups to access valuable sp3-hybridized carbon frameworks.

While fighting food waste is a year-round mission, it's more important than ever around the holidays. This is something to consider during this year's festivities, typically known for an abundance of food.