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Categories: Anthropology: General, Physics: Optics

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In testing the genetic material of current populations in Africa and comparing against existing fossil evidence of early Homo sapiens populations there, researchers have uncovered a new model of human evolution -- overturning previous beliefs that a single African population gave rise to all humans.

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A new study has produced the most detailed genetic analysis of people living in the Canadian province of Newfoundland to date, demonstrating a unique founder population structure that could be used for the identification and study of health-related genetic variants.

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Scientists have precisely identified base pairs of the human genome that remained consistent over millions of years of mammalian evolution, and which play a crucial role in human disease. The team analyzed the genomes of 240 mammals, including humans and identified base pairs that were 'constrained' -- meaning they remained generally consistent -- across mammal species over the course of evolution. The most constrained base pairs in mammals were over seven times more likely to be causal for human disease and complex trait, and over 11 times more likely when researchers looked at the most constrained base pairs in primates alone.

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A new study shows that sand dunes can serve as repositories of fire history and aid in expanding scientific understanding of fire regimes around the world.

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A new study finds that early human species adapted to mosaic landscapes and diverse food resources, which would have increased our ancestor's resilience to past shifts in climate.

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Adapting a detector developed for space X-ray observation, researchers have successfully verify strong-field quantum electrodynamics with exotic atoms.

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Researchers are embarking on a groundbreaking project to mimic the natural process of photosynthesis using bacteria to deliver electrons to a nanocrystal semiconductor photocatalyst. By leveraging the unique properties of microorganisms and nanomaterials, the system has the potential to replace current approaches that derive hydrogen from fossil fuels, revolutionizing the way hydrogen fuel is produced and unlocking a powerful source of renewable energy.

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Researchers describe developing a super-resolution imaging platform technology to improve understanding of how nanoparticles interact within cells.

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Scientists have used mitochondrial DNA to trace a female lineage from northern coastal China to the Americas. By integrating contemporary and ancient mitochondrial DNA, the team found evidence of at least two migrations: one during the last ice age, and one during the subsequent melting period. Around the same time as the second migration, another branch of the same lineage migrated to Japan, which could explain Paleolithic archeological similarities between the Americas, China, and Japan.

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A team of researchers has improved a new generation of organic-inorganic hybrid materials that can improve image quality in X-ray machines, CT scans and other radiation detection and imaging technologies.

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Researchers have developed a new class of integrated photonic devices -- 'leaky-wave metasurfaces' -- that convert light initially confined in an optical waveguide to an arbitrary optical pattern in free space. These are the first to demonstrate simultaneous control of all four optical degrees of freedom. Because they're so thin, transparent, and compatible with photonic integrated circuits, they can be used to improve optical displays, LIDAR, optical communications, and quantum optics.

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Humans inherited genetic material from Neanderthals that affects the shape of our noses, finds a new study.

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Photovoltaics, the conversion of light to electricity, is a key technology for sustainable energy. Since the days of Max Planck and Albert Einstein, we know that light as well as electricity are quantized, meaning they come in tiny packets called photons and electrons. In a solar cell, the energy of a single photon is transferred to a single electron of the material, but no more than one. Only a few molecular materials like pentacene are an exception, where one photon is converted to two electrons instead. This excitation doubling, which is called exciton fission, could be extremely useful for high-efficiency photovoltaics, specifically to upgrade the dominant technology based on silicon. Researchers have now deciphered the first step of this process by recording an ultrafast movie of the photon-to-electricity conversion process, resolving a decades-old debate about the mechanism of the process.

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Researchers have captured one of the fastest movements of a molecule called ferricyanide for the first time by combining two ultrafast X-ray spectroscopy techniques. They think their approach could help map more complex chemical reactions like oxygen transportation in blood cells or hydrogen production using artificial photosynthesis.

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Scientists have used sub-surface imaging and aerial surveys to see through floodplains in the Red Lily Lagoon area of West Arnhem Land in Australia. These ground-breaking methods showed how this important landscape in the Northern Territory was altered as sea levels rose about 8,000 years ago.

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Researchers have demonstrated a prototype lidar system that uses quantum detection technology to acquire 3D images while submerged underwater. The high sensitivity of this system could allow it to capture detailed information even in extremely low-light conditions found underwater.

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Stone tools recovered from near the Senegalese coast extend occupation of the region back to 150 thousand years ago and are comparable to those seen across Africa at this time, but uniquely persist in the region until 10 thousand years ago.

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An international research team has for the first time successfully isolated ancient human DNA from a Paleolithic artefact: a pierced deer tooth discovered in Denisova Cave in southern Siberia. To preserve the integrity of the artefact, they developed a new, nondestructive method for isolating DNA from ancient bones and teeth. From the DNA retrieved they were able to reconstruct a precise genetic profile of the woman who used or wore the pendant, as well as of the deer from which the tooth was taken. Genetic dates obtained for the DNA from both the woman and the deer show that the pendant was made between 19,000 and 25,000 years ago. The tooth remains fully intact after analysis, providing testimony to a new era in ancient DNA research, in which it may become possible to directly identify the users of ornaments and tools produced in the deep past.

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Researchers have developed a new high-speed way to detect the location, size and category of multiple objects without acquiring images or requiring complex scene reconstruction. Because the new approach greatly decreases the computing power necessary for object detection, it could be useful for identifying hazards while driving.

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Researchers have proposed a new evolutionary model for the origin of a kingdom of viruses called Bamfordvirae, suggesting a billion-years evolutionary arms race between two groups within this kingdom and their hosts.