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Categories: Paleontology: Fossils, Physics: Acoustics and Ultrasound
Published Rare 3D fossils show that some early trees had forms unlike any you've ever seen
(via sciencedaily.com) Original source In the fossil record, trees typically are preserved with only their trunks. They don't usually include any leaves to show what their canopies and overall forms may have looked like. In a new study, researchers describe fossilized trees from New Brunswick, Canada with a surprising and unique three-dimensional crown shape.
Published Photonics-based wireless link breaks speed records for data transmission
(via sciencedaily.com) Original source Researchers demonstrated a 300 GHz-band wireless link that was able to transmit data over a single channel at a rate of 240 gigabits per second. The wireless communication system employs signal generators based on lasers that have ultra-low phase noise in the sub-terahertz band. This rate is the highest so far reported at these frequencies and is a substantial step forward in 300 GHz-band communications for 6G networks.
Published Did dementia exist in ancient Greek and Rome?
(via sciencedaily.com) Original source 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.
Published Scientists pinpoint growth of brain's cerebellum as key to evolution of bird flight
(via sciencedaily.com) Original source Evolutionary biologists report they have combined PET scans of modern pigeons along with studies of dinosaur fossils to help answer an enduring question in biology: How did the brains of birds evolve to enable them to fly?
Published How did humans learn to walk? New evolutionary study offers an earful
(via sciencedaily.com) Original source 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.
Published Sound-powered sensors stand to save millions of batteries
(via sciencedaily.com) Original source 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.
Published Virtual noise assessment for passenger jet of the future
(via sciencedaily.com) Original source 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?
Published DNA from preserved feces reveals ancient Japanese gut environment
(via sciencedaily.com) Original source 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.
Published Ancient brown bear genomes sheds light on Ice Age losses and survival
(via sciencedaily.com) Original source 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?
Published New pieces in the puzzle of first life on Earth
(via sciencedaily.com) Original source Microorganisms were the first forms of life on our planet. The clues are written in 3.5 billion-year-old rocks by geochemical and morphological traces, such as chemical compounds or structures that these organisms left behind. However, it is still not clear when and where life originated on Earth and when a diversity of species developed in these early microbial communities. Evidence is scarce and often disputed. Now, researchers have uncovered key findings about the earliest forms of life. In rock samples from South Africa, they found evidence dating to around 3.42 billion years ago of an unprecedentedly diverse carbon cycle involving various microorganisms. This research shows that complex microbial communities already existed in the ecosystems during the Palaeoarchaean period.
Published Uncovering the secrets behind the silent flight of owls
(via sciencedaily.com) Original source 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.
Published Complex green organisms emerged a billion years ago
(via sciencedaily.com) Original source Of all the organisms that photosynthesize, land plants have the most complex form. How did this morphology emerge? A team of scientists has taken a deep dive into the evolutionary history of morphological complexity in streptophytes, which include land plants and many green algae. Their research allowed them to go back in time to investigate lineages that emerged long before land plants existed.
Published Student discovers 200-million-year-old flying reptile
(via sciencedaily.com) Original source Gliding winged-reptiles were amongst the ancient crocodile residents of the Mendip Hills in Somerset, England, researchers at the have revealed.
Published Low-frequency ultrasound can improve oxygen saturation in blood
(via sciencedaily.com) Original source 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.
Published The megalodon was less mega than previously believed
(via sciencedaily.com) Original source A new study shows the Megalodon, a gigantic shark that went extinct 3.6 million years ago, was more slender than earlier studies suggested. This finding changes scientists' understanding of Megalodon behavior, ancient ocean life, and why the sharks went extinct.
Published Towards the quantum of sound
(via sciencedaily.com) Original source 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.
Published Why animals shrink over time explained with new evolution theory
(via sciencedaily.com) Original source The new theoretical research proposes that animal size over time depends on two key ecological factors.
Published Pushing the boundaries of ultrasound imaging: Breaking new ground with ultrafast technology
(via sciencedaily.com) Original source Researchers have achieved a successful contrast agent-free imaging of complex structure of kidney vessels.
Published Woolly mammoth movements tied to earliest Alaska hunting camps
(via sciencedaily.com) Original source 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.
Published Pacific kelp forests are far older that we thought
(via sciencedaily.com) Original source Fossils of kelp along the Pacific Coast are rare. Until now, the oldest fossil dated from 14 million years ago, leading to the view that today's denizens of the kelp forest -- marine mammals, urchins, sea birds -- coevolved with kelp. A recent amateur discovery pushes back the origin of kelp to 32 million years ago, long before these creatures appeared. A new analysis suggests the first kelp grazers were extinct, hippo-like animals called desmostylians.