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Categories: Anthropology: Early Humans, Physics: Acoustics and Ultrasound
Published Actively reducing noise by ionizing air
(via sciencedaily.com) Original source Scientists show that a thin layer of plasma, created by ionizing air, could be promising as an active sound absorber, with applications in noise control and room acoustics.
Published Source-shifting metastructures composed of only one resin for location camouflaging
(via sciencedaily.com) Original source Acoustic source-shifters make observers mis-perceive the location of sound by reproducing a sound emanating from a location different from the actual location of a sound source. Researchers have now developed a design approach to produce high-performance source-shifters using a common polymer for location camouflage. Utilizing inverse design based on topology optimization, this development could pave the way for advanced augmented reality and holography technology.
Published Propellers are louder over ground
(via sciencedaily.com) Original source The effects of the ground on propeller noise have now been measured experimentally.
Published A giant leap forward in wireless ultrasound monitoring for subjects in motion
(via sciencedaily.com) Original source Engineers have developed the first fully integrated wearable ultrasound system for deep-tissue monitoring, including for subjects on the go.
Published Humanity's earliest recorded kiss occurred in Mesopotamia 4,500 years ago
(via sciencedaily.com) Original source Written sources from Mesopotamia suggest that kissing in relation to sex was practiced by the peoples of the ancient Middle East 4,500 years ago.
Published Homo sapiens likely arose from multiple closely related populations
(via sciencedaily.com) Original source 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.
Published Researcher uses mammal DNA to zoom into the human genome with unprecedented resolution
(via sciencedaily.com) Original source 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.
Published Human ancestors preferred mosaic landscapes and high ecosystem diversity
(via sciencedaily.com) Original source 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.
Published Evidence of Ice Age human migrations from China to the Americas and Japan
(via sciencedaily.com) Original source 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.
Published A cocktail party of 3D-printed robot heads
(via sciencedaily.com) Original source Imagine a cocktail party full of 3D-printed, humanoid robots listening and talking to each other. That seemingly sci-fi scene is the goal of an augmented listening laboratory. With precise control over the simulated subjects, the researchers can adjust the parameters of the experiment and even set the machines in motion to simulate neck movements.
Published Nose shape gene inherited from Neanderthals
(via sciencedaily.com) Original source Humans inherited genetic material from Neanderthals that affects the shape of our noses, finds a new study.
Published Scientists recover an ancient woman's DNA from a 20,000-year-old pendant
(via sciencedaily.com) Original source 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.
Published Wearable ultrasound patch provide non-invasive deep tissue monitoring
(via sciencedaily.com) Original source Engineers have developed a stretchable ultrasonic array capable of serial, non-invasive, three-dimensional imaging of tissues as deep as four centimeters below the surface of human skin, at a spatial resolution of 0.5 millimeters. This new method provides a non-invasive, longer-term alternative to current methods, with improved penetration depth.
Published Scientists present evidence for a billion-years arms race between viruses and their hosts
(via sciencedaily.com) Original source 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.
Published Sensor enables high-fidelity input from everyday objects, human body
(via sciencedaily.com) Original source Couches, tables, sleeves and more can turn into a high-fidelity input device for computers using a new sensing system.
Published Information 'deleted' from the human genome may be what made us human
(via sciencedaily.com) Original source What the human genome is lacking compared with the genomes of other primates might have been as crucial to the development of humankind as what has been added during our evolutionary history, according to a new study led by researchers at Yale and the Broad Institute of MIT and Harvard. The new findings, published April 28 in the journal Science, fill an important gap in what is known about historical changes to the human genome.
Published Mammalian evolution provides hints for understanding the origins of human disease
(via sciencedaily.com) Original source Even though it is important to know where these variations are located in the genome, it's also useful to know how or why these genetic variations happened in the first place.
Published Lead vocal tracks in popular music go quiet
(via sciencedaily.com) Original source Scientists carried out an analysis of hundreds of popular song recordings from 1946 to 2020 to determine the lead vocal to accompaniment ratio, or LAR. The study considered the four highest-ranked songs from the Billboard Hot 100 chart for each year and the results show that, contrary to expectations, the LAR for popular music decreased over the decades in question. This means that, relative to their bands, lead singers are getting quieter.
Published Searching for ancient bears in an Alaskan cave led to an important human discovery
(via sciencedaily.com) Original source Genetic analysis links 3,000-year-old bone found in cave to modern Alaska Natives.
Published It's not as difficult as you think to shout upwind
(via sciencedaily.com) Original source Why does it feel so difficult to shout upwind? The sensation is common enough to have found its way into an idiom about not being understood. Researchers wanted a scientific explanation for the phenomenon -- and there wasn't been one. They have now shown that our common sense understanding of this situation is wrong. It isn't harder to shout into the wind; it's just harder to hear yourself.