Organometallic reagents are essential tools in synthetic chemistry. They work even better and more effectively in combination with alkali alkoxides. The exact nature of this effect has never been well understood. A team based in Switzerland has now performed a detailed study of the mechanism of reaction of aryl bromides with organo-magnesium reagents and lithium alkoxides. As reported in the journal Angewandte Chemie, a complex equilibrium of bimetallic intermediates plays a key role. Substituted aromatic ring systems are an important class of building block for the synthesis of many products, including pharmaceuticals, agrochemicals, and ...

Recently, the Laboratory of Micro and Nano Engineering, School of Engineering Science, University of Science and Technology of China (USTC) has made important progress in the field of structural chirality detection research using vortex light and found that photon orbital angular momentum can efficiently detect the optical chiral signal of structures. The achievement was published in an international well-known journal PNAS. Chiral structures are widely found in nature, such as DNA double helix structures, plant tendrils and shells. In addition to observing the geometry of objects, their chirality can also be distinguished by the interaction of light with matter. For example, the detection of circular ...

Aqueous free-radical precipitation polymerization is one of the most useful methods to prepare the uniformly sized hydrogel microspheres (microgels), and an understanding of the polymerization mechanism is crucial to control the structure or physicochemical properties of microgels. However, the details of the mechanism of precipitation polymerization remain unclear. Thus, first author Yuichiro Nishizawa, Prof. Daisuke Suzuki of the Graduate School of Textile Science & Technology, Shinshu University and Prof. Takayuki Uchihashi of Nagoya University set out to clarify the formation mechanism of microgels during precipitation polymerization by evaluating structural evolution and thermoresponsiveness of developing microgels during ...

The study examined the gender and affiliations of 1051 top-authors, those scientists with the most publications in 13 leading ecology and conservation journals. The results show that women and the Global South are barely represented on this list. "The overall list of top authors included only 11% women, while 75% of the articles were related to just five countries in the Global North," says Bea Maas, lead author from the University of Vienna. "This massive imbalance in scientific authorship is extremely concerning, especially in the field of ecology and conservation, ...

The formation of double bonds between two carbon atoms (C=C) is of central significance in natural organisms. The vast majority of natural substances therefore contain one or more of these double bonds. Compounds with C=C double bonds, the alkenes or olefins, also play a prominent role in the organic chemical industry. A great many chemical processes have therefore been developed over the years to control the formation of C=C bonds. One such process, olefin metathesis, has received particular attention over the last few decades and the 2005 Nobel Prize for Chemistry was awarded in recognition of its significance. Despite the many ...

A technological and biological development that is unprecedented in Israel and the world has been achieved at Tel Aviv University. For the first time, the ear of a dead locust has been connected to a robot that receives the ear's electrical signals and responds accordingly. The result is extraordinary: When the researchers clap once, the locust's ear hears the sound and the robot moves forward; when the researchers clap twice, the robot moves backwards. The interdisciplinary study was led by Idan Fishel, a joint master student under the joint supervision of Dr. Ben M. Maoz of the Iby and Aladar Fleischman ...

Removal of pollutants from the air, or atmospheric deposition, is a natural cleaning mechanism. However, the removed toxic matters don't just disappear on the Earth. China's Soil Pollution Survey released in 2014 shows that 19.4% of the Chinese farmland soil was polluted and 82% of pollutant was toxic heavy metals such as cadmium, which can cause chronic health problems. Atmospheric deposition is an important source of these heavy metals in the soil but it tends to be neglected. Unlike sources from irrigation water, sewage sludge, fertilizers and livestock manures, atmospheric deposition can't easily be perceived. And the paucity of measurements also makes it difficult to track what ...

Currently, the roles of free D-amino acids and D-amino acid residues in proteins are garnering extensive attention in biological fields such as molecular biology, physiology, microbiology, and pathophysiology. Because it is crucial to analyze these materials rapidly and accurately, many methods have been employed. However, samples for measurement are currently limited to solutions containing target molecules in the pure form. Hence, there is need for an analytical method for the in situ measurement of biological samples placed on a solid support. We report the construction of a multidimensional ...

Earth's surface environments are highly oxygenated - from the atmosphere to the deepest reaches of the oceans, representing a hallmark of active photosynthetic biosphere. However, the fundamental timescale of the oxygen-rich atmosphere on Earth remains uncertain, particularly for the distant future. Solving this question has great ramifications not only for the future of Earth's biosphere but for the search for life on Earth-like planets beyond the solar system. A new study published in Nature Geoscience this week tackles this problem using a numerical model of biogeochemistry and climate and reveals that the future lifespan ...

In the group of Prof. Karl Leo, physicists, material scientists and engineers are working jointly on the development of novel organic materials and devices for high performance, flexible and possibly even biocompatible electronics and optoelectronics of the future. Increasing the performance of organic devices is one of the key challenges in their research. It was only last year, when the team headed by Dr. Hans Kleemann announced an important breakthrough with the development of efficient, printable vertical organic transistors. Now Dr. Zhongbin Wu, Dr. Yuan Liu, and PhD student Erjuan Guo present the first electronic device that combines a vertical organic permeable base transistor (OPBT) and an OLED. With this novel device concept of an organic permeable base light-emitting ...

Active or voluntary learning is a major topic in education, psychology, and neuroscience. Over the years, numerous studies have shown that when learning occurs through voluntary action, there is a modulation of attention, motivation and cognitive control that makes the process much more effective. Consequently, memory is benefited. However, although the physiological processes underlying this reality had been identified in the brain of mice, their existence in our species had not been corroborated. Now, an international group of researchers led by ICREA Research Professor Paul Verschure from the SPECS laboratory at the Institute for Bioengineering of Catalonia (IBEC) and Professor Nikolai Axmacher from the Department of Neuropsychology at Ruhr-Universität ...

The first observations of a space hurricane have been revealed in Earth's upper atmosphere, confirming their existence and shedding new light on the relationship between planets and space. Hurricanes in the Earth's low atmosphere are known, but they had never before been detected in the upper atmosphere. An international team of scientists led by Shandong University in China analysed observations made by satellites in 2014 to reveal a long-lasting hurricane, resembling those in the lower atmosphere, in the polar ionosphere and magnetosphere with surprisingly large energy and momentum deposition despite otherwise extremely quiet geomagnetic conditions. The analysis ...

The Acheulean was estimated to have died out around 200,000 years ago but the new findings suggest it may have persisted for much longer, creating over 100,000 years of overlap with more advanced technologies produced by Neanderthals and early modern humans. The research team, led by Dr Alastair Key (Kent) alongside Dr David Roberts (Kent) and Dr Ivan Jaric (Biology Centre of the Czech Academy of Sciences), made the discovery whilst studying stone tool records from different regions across the world. Using statistical techniques new to archaeological science, the archaeologists and conservation experts were able to reconstruct the end of the Acheulean period and re-map the archaeological record. Previously, ...

An impressive body of evidence published this week reveals the answer to a mystery that has puzzled plant scientists for more than 30 years: the role of the molecule suberin in the leaves of some of our most productive crops. This discovery could be the key to engineering better crops and ensuring future food security. Highly productive crops such as sugarcane, sorghum and maize belong to the type of plants that use the more efficient C4 photosynthetic pathway to transform water, sunlight and carbon dioxide (CO2) into sugars. Scientists have known for a long time that one of key factors that makes C4 photosynthesis more efficient is that they have the capacity to ...

LOS ALAMOS, N.M., March 1, 2021-- A novel computer algorithm that could create a broadly reactive influenza vaccine for swine flu also offers a path toward a pan-influenza vaccine and possibly a pan-coronavirus vaccine as well, according to a new paper published in Nature Communications. "This work takes us a step closer to a pan-swine flu virus vaccine," said Bette Korber, a computational biologist at Los Alamos National Laboratory and a co-author on the paper. "The hope is to eventually be prepared with an effective and rapid response if another swine flu epidemic begins to spread in humans, but this swine flu vaccine could also be useful in a veterinary setting." The immune responses to the vaccine showed very promising breadth against diverse viral variants. "The same basic principles ...

Nearly everything author Malcolm Gladwell said about how information spreads in his 2000 bestseller "The Tipping Point" is wrong, according to a recent study led by UCLA professor of sociology Gabriel Rossman. "The main point of 'The Tipping Point' is if you want your idea to spread, you find the most popular person in the center of any given network and you sell them on your idea, and then they'll sell the rest of the world on it," Rossman said. But Rossman's latest study, recently published in Proceedings of the National Academy of Sciences, pokes holes in that widely accepted notion ...

Law enforcement seizures of drugs, particularly marijuana and methamphetamine, dropped at the beginning of the COVID-19 pandemic, then increased significantly in the following months--exceeding pre-pandemic seizure rates and providing clues about the impact of the crisis on substance use, according to a new study in the journal Drug and Alcohol Dependence. The research was conducted as part of the National Drug Early Warning System (NDEWS), which uses real-time surveillance to detect early signals of potential drug epidemics. NDEWS is led by a team of researchers at the University of Florida, New York University, and Florida Atlantic University, ...

While natural disasters and economic recessions traditionally unleash an uptick in child abuse, a new study suggests that cases may have declined in the first months of the pandemic, compared with the same timeframe in previous years. In the study, led by UCSF Benioff Children's Hospitals and Children's Mercy Kansas City, researchers tracked the number of pediatric inpatients ages 5 and under in 52 children's hospitals nationwide for the first eight months of 2020. They found a steep decline in the number of ER visits and hospital admissions, including those requiring treatment for physical abuse. This started in mid-March - around the time some states issued shelter-in-place ...

A Ludwig-Maximilians-Universitaet (LMU) in Munich team has shown that slight alterations in transfer-RNA molecules (tRNAs) allow them to self-assemble into a functional unit that can replicate information exponentially. tRNAs are key elements in the evolution of early life-forms. Life as we know it is based on a complex network of interactions, which take place at microscopic scales in biological cells, and involve thousands of distinct molecular species. In our bodies, one fundamental process is repeated countless times every day. In an operation known as replication, proteins duplicate the genetic ...

New research suggests that the ability of green algae to eat bacteria is likely much more widespread than previously thought, a finding that could be crucial to environmental and climate science. The work, led by scientists at the American Museum of Natural History, Columbia University, and the University of Arizona, found that five strains of single-celled green algae consume bacteria when they are "hungry," and only when those bacteria are alive. The study is published today in The ISME Journal. "Traditionally, we think of green algae as being purely photosynthetic organisms, producing their food by soaking in sunlight," said Eunsoo Kim, an associate curator at the American Museum of Natural History and one of the study's corresponding ...

An international team led by Prof. dr habil. Andrzej Niedzielski, an astronomer from the Nicolaus Copernicus University in Torun (Poland), has discovered yet another three extrasolar planets. These planets revolve around the stars that can be called elder sisters of our Sun. You can read about the astronomers' success in Astronomy and Astrophysics. The prestigious European journal will publish the paper: Tracking Advanced Planetary Systems (TAPAS) with HARPS-N. VII. Elder suns with low-mass companions. Apart from Prof. Andrzej Niedzielski from the NCU Institute of Astronomy, the team which worked on the discovery includes Prof. dr habil. Gracjan Maciejewski, also from the NCU Faculty of Physics, Astronomy and Informatics, Prof. Aleksander Wolszczan (Pennsylvania State ...

For several years now, the biofuels that power cars, jet airplanes, ships and big trucks have come primarily from corn and other mass-produced farm crops. Researchers at USC, though, have looked to the ocean for what could be an even better biofuel crop: seaweed. Scientists at the USC Wrigley Institute for Environmental Studies on Santa Catalina Island, working with private industry, report that a new aquaculture technique on the California coast dramatically increases kelp growth, yielding four times more biomass than natural processes. The technique employs a contraption called the "kelp elevator" ...

Australia's marine World Heritage Sites are among the world's largest stores of carbon dioxide according to a new report from the United Nations, co-authored by an ECU marine science expert. The UNESCO report found Australia's six marine World Heritage Sites hold 40 per cent of the estimated 5 billion tons of carbon dioxide stored in mangrove, seagrass and tidal marsh ecosystems within UNESCO sites. The report quantifies the enormous amounts of so-called blue carbon absorbed and stored by those ecosystems across the world's 50 UNESCO marine World Heritage Sites. Despite covering less ...

Rapid COVID-19 tests are on the rise to deliver results faster to more people, and scientists need an easy, foolproof way to know that these tests work correctly and the results can be trusted. Nanoparticles that pass detection as the novel coronavirus could be just the ticket. Such coronavirus-like nanoparticles, developed by nanoengineers at the University of California San Diego, would serve as something called a positive control for COVID-19 tests. Positive controls are samples that always test positive. They are run and analyzed right alongside patient samples to verify that COVID-19 tests are working consistently and as intended. The positive controls developed at UC San Diego offer several advantages over the ones currently used in COVID-19 testing: ...

Around the world there are currently more than 18 billion internet-connected mobile devices. In the next 10 years, anticipated growth in the Internet of Things (IoT) and in machine-type communication in general, will lead to a world of hundreds of billions of data-connected objects. Such growth poses two very challenging problems: How can we securely connect so many wireless devices to the Internet when the radio-frequency bandwidth has already become very scarce? How can all these devices be powered? Regular, manual charging of all mobile Internet-connected devices will not be feasible, and connection to ...