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Categories: Archaeology: General, Engineering: Graphene
Published Using paleogenomics to elucidate 10,000 years of immune system evolution
(via sciencedaily.com) Scientists have used paleogenomics to trace 10,000 years of human immune system evolution. They analyzed the genomes of more than 2,800 individuals who lived in Europe over the past ten millennia. They were able to date the increase in frequency of most of the mutations that are advantageous in defending against pathogens to after the Bronze Age, 4,500 years ago. The scientists also observed that mutations conferring a higher risk of developing inflammatory disorders have become more frequent over the past 10,000 years.
Published Ancient Siberian genomes reveal genetic backflow from North America across the Bering Sea
(via sciencedaily.com) 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.
Published Discovery of a new form of carbon called Long-range Ordered Porous Carbon (LOPC)
(via sciencedaily.com) The most well-known forms of carbon include graphite and diamond, but there are other more exotic nanoscale allotropes of carbon as well. These include graphene and fullerenes, which are sp2 hybridized carbon with zero (flat-shaped) or positive (sphere-shaped) curvatures. Researchers now report the discovery of a new form of carbon formed by heating fullerenes with lithium nitride.
Published Ethical ancient DNA research must involve descendant communities, say researchers
(via sciencedaily.com) 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.
Published Humidity may be the key to super-lubricity 'switch'
(via sciencedaily.com) A material state known as super-lubricity, where friction between two contacting surfaces nearly vanishes, is a phenomenon that materials researchers have studied for years due to the potential for reducing the energy cost and wear and tear on devices, two major drawbacks of friction. However, there are times when friction is needed within the same device, and the ability to turn super-lubricity on and off would be a boon for multiple practical engineering applications.
Published Smallpox has plagued humans since ancient Egyptian times, new evidence confirms
(via sciencedaily.com) Original source 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.
Published Riddle solved: Why was Roman concrete so durable?
(via sciencedaily.com) An unexpected ancient manufacturing strategy may hold the key to designing concrete that lasts for millennia.
Published DNA from archaeological remains shows that immigration to Scandinavia was exceptional during the Viking period
(via sciencedaily.com) 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.
Published How evolution works
(via sciencedaily.com) Original source What genetic changes are responsible for the evolution of phenotypic traits? This question is not always easy to answer. A newly developed method now makes the search much easier.
Published Mayas utilized market-based economics
(via sciencedaily.com) More than 500 years ago in the midwestern Guatemalan highlands, Maya people bought and sold goods with far less oversight from their rulers than many archeologists previously thought. Overtime, the availability of obsidian resources and the prevalence of craftsmen to shape it resulted in a system that is in many ways suggestive of contemporary market-based economies.
Published Researchers discover new process to create freestanding membranes of 'smart' materials
(via sciencedaily.com) A team has developed a new method for making nano-membranes of 'smart' materials, which will allow scientists to harness their unique properties for use in devices such as sensors and flexible electronics.
Published Human brain organoids implanted into mouse cortex respond to visual stimuli for first time
(via sciencedaily.com) A team of engineers and neuroscientists has demonstrated for the first time that human brain organoids implanted in mice have established functional connectivity to the animals' cortex and responded to external sensory stimuli. The implanted organoids reacted to visual stimuli in the same way as surrounding tissues, an observation that researchers were able to make in real time over several months thanks to an innovative experimental setup that combines transparent graphene microelectrode arrays and two-photon imaging.
Published Bering Land Bridge formed surprisingly late during last ice age
(via sciencedaily.com) 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.
Published Archaeologists uncover oldest known projectile points in the Americas
(via sciencedaily.com) 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.
Published At the edge of graphene-based electronics
(via sciencedaily.com) Researchers developed a new graphene-based nanoelectronics platform compatible with conventional microelectronics manufacturing, paving the way for a successor to silicon.
Published New theory on timing for human settlement of some parts of tropical Pacific
(via sciencedaily.com) Spread across vast distances, the islands of the tropical Pacific Ocean are thought to have been populated by humans in two distinct migrations beginning approximately 3,330 years ago. The first followed a northern route out of what is today the Philippines and the second followed a southern route from Taiwan and New Guinea. People arrived on the islands between these routes -- now making up the Federated States of Micronesia -- about 1,000 years later. But a new finding by sea-level researchers suggests that the islands in Micronesia were possibly settled much earlier than supposed and that voyagers on the two routes may have interacted with one another.
Published Lucky find! How science behind epidemics helped physicists to develop state-of-the-art conductive paint
(via sciencedaily.com) Scientists demonstrate how a highly conductive paint coating that they have developed mimics the network spread of a virus through a process called 'explosive percolation' -- a mathematical process which can also be applied to population growth, financial systems and computer networks, but which has not been seen before in materials systems. The finding was a serendipitous development as well as a scientific first for the researchers.
Published A shield for 2D materials that adds vibrations to reduce vibration problems
(via sciencedaily.com) 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.
Published Drought encouraged Attila's Huns to attack the Roman empire, tree rings suggest
(via sciencedaily.com) Hunnic peoples migrated westward across Eurasia, switched between farming and herding, and became violent raiders in response to severe drought in the Danube frontier provinces of the Roman empire, a new study argues.
Published True giant wombat gives Diprotodon podium a wobble
(via sciencedaily.com) While the Diprotodon -- the extinct megafauna species that is distantly related to wombats but was the size of a small car -- is commonly (but incorrectly) thought of as Australia's 'giant wombat', researchers have shed light on a large species that does belong in the modern-day wombat family. The complete skull of this true fossil giant wombat, found in a Rockhampton cave in Queensland, Australia and estimated to be around 80,000 years old, has been described for the first time.