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Categories: Anthropology: General, Chemistry: Inorganic Chemistry

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Societies and political structures, like the humans they serve, appear to become more fragile as they age, according to an analysis of hundreds of pre-modern societies. A new study, which holds implications for the modern world, provides the first quantitative support for the theory that the resilience of political states decreases over time. 

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Researchers give medieval Cambridge residents the 'Richard III treatment' to reveal hard-knock lives of those in the city during its famous university's early years. Study of over 400 remains from a hospital cemetery shows spectrum of medieval poverty, and suggests that some of Cambridge University's earliest scholars ended up in penury.   

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Research suggests that Paleolithic humans in the Middle East selected flint for their cutting tools based on differences in the mechanical properties of the rock. They seem to have purposefully selected the most suitable rocks for fashioning into tools, even being able to distinguish rocks that were unsuitable.

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Hydrogen is a building block for the energy transition. To obtain it with the help of solar energy, researchers have developed new high-performance nanostructures. The material holds a world record for green hydrogen production with sunlight.

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Friction is hard to predict and control, especially since surfaces that come in contact are rarely perfectly flat. New experiments demonstrate that the amount of friction between two silicon surfaces, even at large scales, is determined by the forming and rupturing of microscopic chemical bonds between them. This makes it possible to control the amount of friction using surface chemistry techniques.

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A collaborative research team has discovered a new process for making anhydrides that promises improvements in costs and sustainability.

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Maize is one of the world's most widely grown crops. It is used for both human and animal foods and holds great cultural significance, especially for indigenous peoples in the Americas. Yet despite its importance, the origins of the grain have been hotly debated for more than a century. Now new research shows that all modern maize descends from a hybrid created just over 5000 years ago in central Mexico, thousands of years after the plant was first domesticated.

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Long before researchers discovered the electron and its role in generating electrical current, they knew about electricity and were exploring its potential. One thing they learned early on was that metals were great conductors of both electricity and heat. And in 1853, two scientists showed that those two admirable properties of metals were somehow related: At any given temperature, the ratio of electronic conductivity to thermal conductivity was roughly the same in any metal they tested. This so-called Wiedemann-Franz law has held ever since -- except in quantum materials. Now, a theoretical argument put forth by physicists suggests that the law should, in fact, approximately hold for one type of quantum material, the cuprate superconductors.

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A recent study demonstrates how dripstones can be crucial for reconstructing past climates. The new approach can provide a detailed picture of the climate around early human occupations in South Africa.

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To ensure that vaccines provide strong and lasting immunization, it is often necessary to supplement the actual vaccine (antigen) with additives that stimulate the immune system: adjuvants. Today, only a few substances have been approved for use as adjuvants. A research team has now introduced a spectrum of potential adjuvants. They started with the immune stimulant ?-glactosyl ceramide (?-GalCer) and synthesized many different variants from a set of four building blocks.

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Found in fishing nets, carpet, clothing, Nylon-6 is a major contributor to plastic pollution, including ocean pollution. Now, chemists have developed a new catalyst that quickly, cleanly and completely breaks down Nylon-6 in a matter of minutes -- without generating harmful byproducts. Even better: The process does not require toxic solvents, expensive materials or extreme conditions, making it practical for everyday applications. In experiments, the new process recovered 99% of the polymer's building blocks, which can then be upcycled into higher-value products.

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Scientists should seek answers hidden in the dirt using proven and state-of-the-art archaeological science techniques to support new discoveries about human evolution following recent controversies at a cave site in Africa, says a group of international experts. Their recommendations follow claims published in June of this year that Homo naledi --a small-brained human species -- buried their dead in Rising Star Cave, South Africa, between 335,000 and 241,000 years ago, and may also have decorated the cave walls with engravings.

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The Second Plague Pandemic of the mid-14th century, also known as the Black Death, killed 30-60 percent of the European population and profoundly changed the course of European history. New research suggests that this plague, potentially through resulting changes in diet and hygiene, may also be associated with a shift in the composition of the human oral microbiome toward one that contributes to chronic diseases in modern-day humans.  

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Researchers have developed an AI model that can predict where a drug molecule can be chemically altered.

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Used lithium-ion batteries from cell phones, laptops and a growing number of electric vehicles are piling up, but options for recycling them remain limited mostly to burning or chemically dissolving shredded batteries. Researchers have improved on approaches that dissolve the battery in a liquid solution in order to reduce the amount of hazardous chemicals used in the process. This simple, efficient and environmentally-friendly solution overcomes the main obstacles presented by previous approaches.

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Researchers have demonstrated a compact particle accelerator less than 20 meters long that produces an electron beam with an energy of 10 billion electron volts (10 GeV). There are only two other accelerators currently operating in the U.S. that can reach such high electron energies, but both are approximately 3 kilometers long. This type of accelerator is called a wakefield laser accelerator.

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The national park of Koli in eastern Finland is home to a famous, 34-metre-long crevice cave known as Pirunkirkko, or Devil's Church in English. A new study investigates the acoustics of the Devil's Church and explores whether the acoustic properties of the cave could explain the beliefs associated with it, and why it was chosen as a place for activities and rituals involving sound.

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Researchers have devised a way to produce chemicals used in medicine and agriculture for a fraction of the usual cost. Using oxygen as a reagent and copper as a catalyst to break organic molecules' carbon-carbon bonds and convert them into amines, which are widely used in pharmaceuticals. Traditional metal catalysis uses expensive metals such as platinum, silver, gold and palladium, but the researchers used oxygen and copper -- an abundant base metal.

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Modern hippos first dispersed in Europe during the Middle Pleistocene, according to a new study.

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Researchers create transistors combining silicon with biological silk, using common microprocessor manufacturing methods. The silk protein can be easily modified with other chemical and biological molecules to change its properties, leading to circuits that respond to biology and the environment.