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Categories: Anthropology: General, Chemistry: General

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Between 1840 and 1867, thousands of enslaved Africans who had been 'liberated' from slave ships intercepted by the British Royal Navy were taken to the South Atlantic island of St Helena. But little is written in history books or otherwise known about the lives of these individuals. Now, ancient DNA analyses offer the first direct evidence for the origins of St Helena's liberated Africans.

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From the Middle Ages to the Enlightenment, 'monstrous births' -- malformed or anomalous fetuses -- were, to Western medicine, an object of superstition. In 19th-century America, they became instead an object of the 'modern scientific study of monstrosity,' a field formalized by French scientist Isidore Geoffroy Saint-Hilaire. This clinical turn was positioned against the backdrop of social, political, and economic activity that codified laws governing slavery, citizenship, immigration, family, wealth, and access to resources.

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Sulfinate esters, a type of organosulfur compounds, are typically synthesized using thiols. However, these substances are difficult to work with due to their unpleasant smell and oxidizability in air. Now, a research team has found a way to produce sulfinate esters through the direct oxidation of thioesters, which are easily accessible and stable. Their findings will help expand the field of organosulfur chemistry and hopefully lead to new applications in pharmaceuticals.

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Chemists have extended a powerful molecule-building method -- called C-H activation -- to the broad class of chemicals known as alcohols.

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A recent study has unveiled a significant breakthrough in photoelectrode development.

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Researchers report that the flexible shoulders and elbows that allow us to throw a football or reach a high shelf may have evolved as a natural braking system that let our primate ancestors get out of trees without dying. The researchers used sports-analysis software to compare the climbing movements of chimpanzees and small monkeys called mangabeys. While the animals climb up trees similarly, the researchers found that the shallow, rounded shoulder joints and shortened elbow bones that chimps have -- similar to humans -- allow them to fully extend their arms above their heads when climbing down, holding onto branches like a person going down a ladder to support their greater weight. When early humans left forests for the grassy savanna, these versatile appendages would have been essential for gathering food and using tools for hunting and defense. The findings are among the first to identify the significance of 'downclimbing' in the evolution of apes and early humans.

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If the region surrounding Chicago -- North America's largest freight hub -- shifted just 30% of its current on-road heavy-duty vehicles to electric versions, it would substantially reduce pollution and save hundreds of lives per year, with the benefits largely concentrated in disadvantaged communities, according to a new study. The study authors highlight that neighborhoods with predominantly Black, Hispanic and Latinx residents would benefit the most -- potentially reducing disproportionate pollution and health burdens in historically marginalized areas.

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A new study has uncovered intriguing insights into the evolution of plant biology, effectively rewriting the history of how they evolved over the past billion years.

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Important progress for RNA research: A team has discovered a new ribozyme that can label RNA molecules in living cells.

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Urban stormwater particles from tire wear were the most prevalent microplastic a new study has found. The study showed that in stormwater runoff during rain approximately 19 out of every 20 microplastics collected were tire wear particles with anywhere from 2 to 59 particles per liter of water. Tire rubber contains up to 2500 chemicals with the contaminants that leach from tires considered more toxic to bacteria and microalgae than other plastic polymers.

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Carbon dioxide can be electrocatalytically reduced to useful resources using conventional catalysts such as gold or lead supported on conductive carbon. However, the high pH environment near electrodes often degrades the catalyst support, rendering them ineffective. Now, researchers have developed novel in-liquid plasma-treated titanium dioxide electrode decorated with silver nanoparticles as an alternate catalyst support, facilitating enhanced conversion of carbon dioxide to useful products, such as syngas, a clean alternative to fossil fuels.

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Lithium-ion batteries (LIBs) provide our portable devices like tablets and mobiles -- and increasingly also vehicles -- with power. As the share of volatile renewable energy needing electricity storage increases, more and more LIBs are needed, lithium prices rise, resources dwindle, and the amount of depleted batteries that contain toxic substances increases. Researchers introduce a novel approach for the recovery of lithium from used LIBs.

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A 'living material,' made of a natural polymer combined with genetically engineered bacteria, could offer a sustainable and eco-friendly solution to clean pollutants from water. Researchers developed their living material using a seaweed-based polymer and bacteria that have been programmed to produce an enzyme that transforms various organic pollutants into harmless compounds. In tests, heir material decontaminated water solutions tainted with a pollutant from textile manufacturing: indigo carmine, a blue dye that is used to color denim.

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The Qing Dynasty in China, after over 250 years, crumbled in 1912. An international research team has pinpointed key reasons behind the collapse, revealing parallels to modern instability and offering vital lessons for the future.

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Hydrogen spillover is exactly what it sounds like. Small metal nanoparticles anchored on a thermally stable oxide, like silica, comprise a major class of catalysts, which are substances used to accelerate chemical reactions without being consumed themselves. The catalytic reaction usually occurs on the reactive -- and expensive -- metal, but on some catalysts, hydrogen atom-like equivalents literally spill from the metal to the oxide. These hydrogen-on-oxide species are called 'hydrogen spillover.'

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A main crux of neuroscience is learning how our senses translate light into sight, sound into hearing, food into taste, and texture into touch. Smell is where these sensory relationships get more complex and perplexing. To address this question, a research team are investigating how airborne chemicals connect to odor perception in the brain. They discovered that a machine-learning model has achieved human-level proficiency at describing, in words, what chemicals smell like.

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By controlling the arrangement of multiple inorganic and organic layers within crystals using a novel technique, researchers have shown they can control the energy levels of electrons and holes (positive charge carriers) within a class of materials called perovskites. This tuning influences the materials' optoelectronic properties and their ability to emit light of specific energies, demonstrated by their ability to function as a source of lasers.

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A team of researchers has recreated one of the scents used in the mummification of an important Egyptian woman more than 3500 years ago.

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Researchers have been able to substantially improve photoclick chemistry. They were able to boost the reactivity of the photoclick compound in the popular PQ-ERA reaction through strategic molecular substitution. They now report a superb photoreaction quantum yield, high reaction rates and notable oxygen tolerance.

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Machine learning model provides quick method for determining the composition of solid chemical mixtures using only photographs of the sample.