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Categories: Paleontology: Early Mammals and Birds, 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 Nearly a hundred genes have been lost during the woolly mammoth's evolution


A new study shows that 87 genes have been affected by deletions or short insertions during the course of the mammoth's evolution. The researchers note that their findings have implications for international efforts to resurrect extinct species, including the woolly mammoth.
Published CT scanner captures entire woolly mammoth tusk


Researchers successfully captured CT images of an entire woolly mammoth tusk. Researchers were able to do a full scan of the tusk in its entirety -- or in toto -- using a newer clinical CT scanner. The new technology allows for large-scale imaging without having to do multiple partial scans.
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 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 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 New study challenges old views on what's 'primitive' in mammalian reproduction


Which group of mammals has the more 'primitive' reproductive strategy -- marsupials, with their short gestation periods, or humans and other placental mammals, which have long gestation periods? For decades, biologists viewed marsupial reproduction as 'more primitive.' But scientists have discovered that a third group of mammals, the long-extinct multituberculates, had a long gestation period like placental mammals. Since multituberculates split off from the rest of the mammalian lineage before placentals and marsupials had even evolved, these findings question the view that marsupials were 'less advanced' than their placental cousins.
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 The size of mammal ancestors' ear canals reveal when warm-bloodedness evolved


Warm-bloodedness is a key mammal trait, but it's been a mystery when our ancestors evolved it. A new study points to an unlikely source for telling a fossil animal's body temperature: the size of tiny structures in their inner ears. The fluid in our ears becomes runnier at higher temperatures, so animals with warm bodies don't need as big of canals for it to flow through. Turns out, mammal ancestors became warm-blooded nearly 20 million years later than previously thought.
Published Australian vulture emerges from fossil record


Australia's first fossil vulture has been confirmed more than 100 years after it was first described as an eagle. The discovery highlights the diversity of Australian megafauna and other animals many thousands of years ago in the Pleistocene period.
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 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 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 Coevolution of mammals and their lice


According to a new study, the first louse to take up residence on a mammalian host likely started out as a parasite of birds. That host-jumping event tens of millions of years ago began the long association between mammals and lice, setting the stage for their coevolution and offering more opportunities for the lice to spread to other mammals.
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.
Published New kangaroo described -- from Papua New Guinea


Australian palaeontologists have described a new genus of giant fossil kangaroo from the mountains of central Papua New Guinea. The new description of the fossil kangaroo has found that, rather than being closely related to Australian kangaroos, it most likely belongs to a unique genus of more primitive kangaroo found only in PNG.