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Categories: Archaeology: General, Physics: Acoustics and Ultrasound

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Did the ancient Greeks and Romans experience Alzheimer's? Medical texts from 2,500 years ago rarely mention severe memory loss, suggesting today's widespread dementia stems from modern environments and lifestyles, a new analysis shows.

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Rickets ran rife in children following the Industrial Revolution, but new research has found factory work and polluted cities aren't entirely to blame for the period's vitamin D deficiencies.

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Archaeologists have debated whether Neanderthals or modern humans made stone tools that are found at sites across northern Europe and date from about 40,000 years ago. A new excavation at one site in Germany turned up 45,000-year-old bone fragments that, when analyzed for mitochondrial DNA, proved to be from Homo sapiens. This is the earliest evidence that modern humans overlapped with Neanderthals in northwest Europe, thousands of years before Neanderthals went extinct.

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A new study, which centers on evidence from skulls of a 6-million-year-old fossil ape, Lufengpithecus, offers important clues about the origins of bipedal locomotion courtesy of a novel method: analyzing its bony inner ear region using three-dimensional CT-scanning. The inner ear appears to provide a unique record of the evolutionary history of ape locomotion.

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Researchers are developing a new type of sensor that reacts to certain sound waves, causing it to vibrate. The sensor is a metamaterial that acquires its special properties through the structuring of the material. Passive sound-sensitive sensors could be used to monitor buildings, earthquakes or certain medical devices and save millions of batteries.

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Instead of tubular commercial aircraft, other designs could be used in the future: Jets with a blended wing body would fly more efficiently and make less noise -- but how would the noise emissions from these new types of aircraft affect people?

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Analysis of the remains of 24 individuals from the Wilamaya Patjxa and Soro Mik'aya Patjxa burial sites in Peru shows that early human diets in the Andes Mountains were composed of 80 percent plant matter and 20 percent meat.

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DNA from ancient feces can offer archaeologists new clues about the life and health of Japanese people who lived thousands of years ago, according to a new study.

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The brown bear is one of the largest living terrestrial carnivores, and is widely distributed across the Northern Hemisphere. Unlike many other large carnivores that went extinct at the end of the last Ice Age (cave bear, sabretoothed cats, cave hyena), the brown bear is one of the lucky survivors that made it through to the present. The question has puzzled biologists for close to a century -- how was this so?

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Owls produce negligible noise while flying. While many studies have linked the micro-fringes in owl wings to their silent flight, the exact mechanisms have been unclear. Now, a team of researchers has uncovered the effects of these micro-fringes on the sound and aerodynamic performance of owl wings through computational fluid dynamic simulations. Their findings can inspire biomimetic designs for the development of low-noise fluid machinery.

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Scientists have revealed that low-frequency ultrasound influences blood parameters. The findings suggest that ultrasound's effect on haemoglobin can improve oxygen's transfer from the lungs to bodily tissues. The research was undertaken on 300 blood samples collected from 42 pulmonary patients.

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A team of scientists has succeeded in cooling traveling sound waves in wave-guides considerably further than has previously been possible using laser light. This achievement represents a significant move towards the ultimate goal of reaching the quantum ground state of sound in wave-guides. Unwanted noise generated by the acoustic waves at room temperature can be eliminated. This experimental approach both provides a deeper understanding of the transition from classical to quantum phenomena of sound and is relevant to quantum communication systems and future quantum technologies.

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For almost 200 years, archaeologists have been puzzled by a mysterious brown stain on the ancient Greek Parthenon temple in Greece. Now, researchers have conducted new scientific analyses, and their verdict is clear: The mystery remains.

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Researchers have achieved a successful contrast agent-free imaging of complex structure of kidney vessels.

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When combined with data from tree-ring records, stalagmites can open up a unique archive to study natural climate fluctuations, a research team has demonstrated. The researchers analyzed the isotopic composition of oxygen in a stalagmite formed from calcareous water in a cave in southern Germany. In conjunction with the data acquired from tree rings, they were able to reconstruct short-term climate fluctuations over centuries and correlate them with historically documented environmental events.

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Researchers have linked the travels of a 14,000-year-old woolly mammoth with the oldest known human settlements in Alaska, providing clues about the relationship between the iconic species and some of the earliest people to travel across the Bering Land Bridge. Isotopic data, along with DNA from other mammoths at the site and archaeological evidence, indicates that early Alaskans likely structured their settlements to overlap with areas where mammoths congregated. Those findings, highlighted in the new issue of the journal Science Advances, provide evidence that mammoths and early hunter-gatherers shared habitat in the region. The long-term predictable presence of woolly mammoths would have attracted humans to the area.

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New research has precisely dated some of the oldest fossils of complex multicellular life in the world, helping to track a pivotal moment in the history of Earth when the seas began teeming with new lifeforms -- after four billion years of containing only single-celled microbes.

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The world is filled with a myriad of sounds and vibrations -- the gentle tones of a piano drifting down the hall, the relaxing purr of a cat laying on your chest, the annoying hum of the office lights. Imagine being able to selectively tune out noises of a certain frequency. Researchers have now synthesized polymer networks with two distinct architectures and crosslink points capable of dynamically exchanging polymer strands to understand how the network connectivity and bond exchange mechanisms govern the overall damping behavior of the network. The incorporation of dynamic bonds into the polymer network demonstrates excellent damping of sound and vibrations at well-defined frequencies.

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Researchers have identified a 3D fragment of fossilized skin that is at least 21 million years than previously described skin fossils. The skin, which belonged to an early species of Paleozoic reptile, has a pebbled surface and most closely resembles crocodile skin. It's the oldest example of preserved epidermis, the outermost layer of skin in terrestrial reptiles, birds, and mammals, which was an important evolutionary adaptation in the transition to life on land.

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A new study shows how state-of-the-art methods and perspectives from archaeology, history, and palaeoecology are shedding new light on 5,500 years of urban life.