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Categories: Anthropology: General, Chemistry: Thermodynamics

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Flexible compounds made with Nobel-winning click chemistry can be used in energy-storing capacitors at high temperatures and electric fields.

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Crocodiles were mummified in a unique way at the Egyptian site of Qubbat al-Hawa during the 5th Century BC, according to a new study.

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Neanderthals in Combe-Grenal (France) preferred to hunt in open environments, and their hunting strategies did not alter during periods of climatic change, according to a new study.

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While humans have been evolving for millions of years, the past 12,000 years have been among the most dynamic and impactful for the way we live today, according to an anthropologist.

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An international team of researchers achieves completely new insights into Bronze Age marriage rules and family structures in Greece. Analyses of ancient genomes show that the choice of marriage partners was determined by one's own kinship.

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Despite their huge potential, the way perovskite solar cells respond to external stimuli -- such as heat or moisture -- has a considerable impact on their stability. Researchers have identified the cause of degradation and developed a technique to improve stability, bringing us closer to widespread adoption of these cost-effective and efficient solar cells.

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The movement of people across the Bering Sea from North Asia to North America is a well-known phenomenon in early human history. Nevertheless, the genetic makeup of the  people who lived in North Asia during this time has remained mysterious due to a limited number of ancient genomes analyzed from this region. Now, researchers describe genomes from ten individuals up to 7,500 years old that help to fill the gap and show geneflow from people moving in the opposite direction from North America to North Asia.

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Synthesizing ammonia, the key ingredient in fertilizer, is energy intensive and a significant contributor to greenhouse gas warming of the planet. Chemists designed and synthesized porous materials -- metal-organic frameworks, or MOFs -- that bind and release ammonia at more moderate pressures and temperatures than the standard Haber-Bosch process for making ammonia. The MOF doesn't bind to any of the reactants, making capture and release of ammonia less energy intensive and greener.

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The analysis of ancient DNA allows scientists to trace human evolution and make important discoveries about modern populations. The data revealed by ancient DNA sampling can be valuable, but the human remains that carry this ancient DNA are often those of the ancestors of modern Indigenous groups, and some communities have expressed concerns about the ethics of sampling by outside parties. A group of scientists make the case for involvement of descendant communities in all aspects of the research process.

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Pyroelectric catalysis (pyro-catalysis) can convert environmental temperature fluctuations into clean chemical energy, like hydrogen. However, compared with the more common catalysis strategy, such as photocatalysis, pyro-catalysis is inefficient due to slow temperature changes in the ambient environment. Recently, a team has triggered a significantly faster and more efficient pyro-catalytic reaction using localized plasmonic heat sources to rapidly and efficiently heat up the pyro-catalytic material and allow it to cool down. The findings open up new avenues for efficient catalysis for biological applications, pollutant treatment and clean energy production.

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Smallpox was once one of humanity's most devastating diseases, but its origin is shrouded in mystery. For years, scientific estimates of when the smallpox virus first emerged have been at odds with historical records. Now, a new study reveals that the virus dates back 2,000 years further than scientists have previously shown, verifying historical sources and confirming for the first time that the disease has plagued human societies since ancient times.

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Using a new method based upon comparing DNA mutation rates between parents and offspring, evolutionary biologists have revealed the average age of mothers versus fathers over the past 250,000 years, including the discovery that the age gap is shrinking, with women's average age at conception increasing from 23.2 years to 26.4 years, on average, in the past 5,000 years.

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A new study based on 297 ancient Scandinavian genomes analysed together with the genomic data of 16,638 present day Scandinavians resolve the complex relations between geography, ancestry, and gene flow in Scandinavia -- encompassing the Roman Age, the Viking Age and later periods. A surprising increase of variation during the Viking period indicates that gene flow into Scandinavia was especially intense during this period.

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Multinuclear organometallic junctions might be the key to realizing high-performance thermoelectric devices at the nanoscale. The unique electronic structure of organometallic ruthenium alkynyl complexes allowed the researchers to achieve unprecedented heat-to-electricity conversion performance in molecular junctions, paving the way to molecular-scale temperature sensors and thermal energy harvesters.

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A new kind of solar panel has achieved 9% efficiency in converting water into hydrogen and oxygen--mimicking a crucial step in natural photosynthesis. Outdoors, it represents a major leap in the technology, nearly 10 times more efficient than solar water-splitting experiments of its kind.

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Researchers have developed a new kind of heating and cooling method that they have named the ionocaloric refrigeration cycle. They hope the technique will someday help phase out refrigerants that contribute to global warming and provide safe, efficient cooling and heating for homes.

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A new study that reconstructs the history of sea level at the Bering Strait shows that the Bering Land Bridge connecting Asia to North America did not emerge until around 35,700 years ago, less than 10,000 years before the height of the last ice age (known as the Last Glacial Maximum). The findings indicate that the growth of the ice sheets -- and the resulting drop in sea level -- occurred surprisingly quickly and much later in the glacial cycle than previous studies had suggested.

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Archaeologists have uncovered projectile points in Idaho that are thousands of years older than any previously found in the Americas, helping to fill in the history of how early humans crafted and used stone weapons.

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Analysis of more than 1,200 vessels from hunter-gatherer sites has shown that pottery-making techniques spread vast distances over a short period of time through social traditions being passed on.

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A new study demonstrates a new, counterintuitive way to protect atomically-thin electronics -- adding vibrations, to reduce vibrations. By squeezing a liquid-metal gallium droplet, graphene devices are painted with a protective coating of gallium-oxide that can cover millimeter-wide scales, making it potentially applicable for industrial large-scale fabrication. The new technique improves device performance as well as protecting 2D materials from thermal vibration in neighboring materials.