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Categories: Anthropology: Early Humans, Physics: Acoustics and Ultrasound
Published Do wind instruments disperse COVID aerosol droplets?


Orchestral ensembles have faced many challenges when starting to perform again during the COVID pandemic, and contamination is a chief concern: specifically, whether wind instruments are vectors of contamination through aerosol dispersion. Researchers worked with musicians to deepen our understanding of how much aerosol is produced and dispersed by wind instruments. They used visualization to characterize the flow, tracked fog particles in the air, and measured aerosol concentration from wind instruments with a particle counter. Then they combined these to develop an equation to describe aerosol dispersion.
Published Using sound and bubbles to make bandages stickier and longer lasting


Researchers have discovered that they can control the stickiness of adhesive bandages using ultrasound waves and bubbles. This breakthrough could lead to new advances in medical adhesives, especially in cases where adhesives are difficult to apply such as on wet skin.
Published Ultrasound could save racehorses from bucked shins


When racehorses enter training at about 2 years old, they can develop tiny stress fractures and new bone formations in their legs. This condition, called bucked shin, occurs in about 70% of the animals. Researchers have now developed a method to screen for bucked shin using ultrasound. Axial transmission, in which an ultrasound emitter and receiver are placed on the skin to induce and measure wave velocities, is frequently used to study osteoporosis in humans. The method could detect bucked shin more easily and preserve the health and growth of young horses.
Published Leadership online: Charisma matters most in video communication


Managers need to make a consistent impression in order to motivate and inspire people, and that applies even more to video communication than to other digital channels. Researchers investigated the influence that charismatic leadership tactics used in text, audio and video communication channels have on employee performance. They focused on mobile work and the gig economy, in which jobs are flexibly assigned to freelancers via online platforms.
Published No, the human brain did not shrink 3,000 years ago


Did the 12th century B.C.E. -- a time when humans were forging great empires and developing new forms of written text -- coincide with an evolutionary reduction in brain size? Think again, says a team of researchers whose new paper refutes a hypothesis that's growing increasingly popular among the science community.
Published What's new under the sun? Offering an alternate view on how 'novel' structures evolve


New research provide evidence that the crustacean carapace, along with other plate-like structures in arthropods (crustaceans, insects, arachnids, and myriapods) all evolved from a lateral leg lobe in a common ancestor more than 500 million years ago. This work further supports their proposal for a new concept of how novel structures evolve -- one which suggests that they aren't so novel, after all.
Published Taking your time makes a difference


Researchers find that stem cells in the developing brain of modern humans take longer to divide and make fewer errors when distributing their chromosomes to their daughter cells, compared to those of Neanderthals.
Published Engineers develop stickers that can see inside the body


Engineers designed an adhesive patch that produces ultrasound images of the body. The stamp-sized device sticks to skin and can provide continuous ultrasound imaging of internal organs for 48 hours.
Published Ancient DNA clarifies the early history of American colonial horses


A newly identified 16th century horse specimen is among the oldest domestic horses from the Americas known to date, and its DNA helps clarify the history of horses in the Western Hemisphere, according to a new study.
Published Early hunting, farming homogenized mammal communities of North America


Whether by the spear or the plow, humans have been homogenizing the mammal communities of North America for 10,000-plus years, says a new analysis of 8,831 fossils representing 365 species.
Published Improving image sensors for machine vision


Researchers highlight the latest nanostructured components integrated on image sensor chips that are most likely to make the biggest impact in multimodal imaging and detailed a promising approach to detect multiple-band spectra by fabricating an on-chip spectrometer. The developments could enable autonomous vehicles to see around corners instead of just a straight line, biomedical imaging to detect abnormalities at different tissue depths, and telescopes to see through interstellar dust.
Published Flexible method for shaping laser beams extends depth-of-focus for OCT imaging


Researchers have developed a new method for flexibly creating various needle-shaped laser beams. These long, narrow beams can be used to improve optical coherence tomography (OCT), a noninvasive and versatile imaging tool that is used for scientific research and various types of clinical diagnoses.
Published When did the genetic variations that make us human emerge?


The study of the genomes of our closest relatives, the Neanderthals and Denisovans, has opened up new research paths that can broaden our understanding of the evolutionary history of Homo sapiens. A new study has made an estimation of the time when some of the genetic variants that characterize our species emerged. It does so by analyzing mutations that are very frequent in modern human populations, but not in these other species of archaic humans.
Published Music-making and the flow of aerosols


If simply breathing can spread the SARS-CoV-2 virus to others nearby, what about blowing into a tuba? Researchers used fluid mechanics to study the movement of aerosols generated by professional musicians.
Published DNA from ancient population in Southern China suggests Native Americans' East Asian roots


For the first time, researchers successfully sequenced the genome of ancient human fossils from the Late Pleistocene in southern China. The data suggests that the mysterious hominin belonged to an extinct maternal branch of modern humans that might have contributed to the origin of Native Americans.
Published Eco-friendly sound absorbers from seaweed


From airplanes to apartments, most spaces are now designed with sound-absorbing materials that help dampen the droning, echoing and murmuring sounds of everyday life. But most of the acoustic materials that can cancel out human voices, traffic and music are made from plastic foams that aren't easily recycled or degraded. Now, researchers have created a biodegradable seaweed-derived film that effectively absorbs sounds in this range.
Published The importance of elders


In a new paper, researchers challenge the longstanding view that the force of natural selection in humans must decline to zero once reproduction is complete. They assert that a long post-reproductive lifespan is not just due to recent advancements in health and medicine. The secret to our success? Our grandparents.
Published Scientists invent 'quantum flute' that can make particles of light move together


Physicists have invented a 'quantum flute' that, like the Pied Piper, can coerce particles of light to move together in a way that's never been seen before.
Published How placentas evolved in mammals


The fossil record tells us about ancient life through the preserved remains of body parts like bones, teeth and turtle shells. But how to study the history of soft tissues and organs, which can decay quickly, leaving little evidence behind? In a new study, scientists use gene expression patterns, called transcriptomics, to investigate the ancient origins of one organ: the placenta, which is vital to pregnancy.
Published Hearing better with skin than ears


A research team develops a sound-sensing skin-attachable acoustic sensor. The new sensor decreased in size and increased in flexibility and is applicable as auditory electronic skin.