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Categories: Paleontology: Fossils, Physics: Acoustics and Ultrasound
Published Geoscientists map changes in atmospheric carbon dioxide over past 66 million years



An international consortium of geoscientists has reconstructed atmosphereric levels of carbon dioxide going back 66 million years using proxies in the geoloogical record. Today's concenteration, 420 parts per million, is higher than it's ever been in 14 million years.
Published Soundwaves harden 3D-printed treatments in deep tissues



Engineers have developed a bio-compatible ink that solidifies into different 3D shapes and structures by absorbing ultrasound waves. Because the material responds to sound waves rather than light, the ink can be used in deep tissues for biomedical purposes ranging from bone healing to heart valve repair.
Published Baboons in captivity in Ancient Egypt: insights from collection of mummies



Baboons were raised in captivity before being mummified in Ancient Egyptian sites, according to a new study.
Published Teaching physics from the din of flying discs



The sound a disc makes while soaring through the air is full of information about how fast the disc is flying and how quickly it spins. This inspired Kyle S. Dalton of Penn State University to combine disc golf and acoustics into an interactive acoustic signal processing lesson. He set three microphones in a line and connected them to equipment that converts each microphone's signal to a data point. Then he threw a disc with a small whistle mounted on top and recorded the flying disc's acoustical signal. The resulting dataset can be used to learn basic processing tools and practice data visualization.
Published Earliest-known fossil mosquito suggests males were bloodsuckers too



Researchers have found the earliest-known fossil mosquito in Lower Cretaceous amber from Lebanon. What's more, the well-preserved insects are two males of the same species with piercing mouthparts, suggesting they likely sucked blood. That's noteworthy because, among modern-day mosquitoes, only females are hematophagous, meaning that they use piercing mouthparts to feed on the blood of people and other animals.
Published Crocodile family tree mapped: New light shed on croc evolution



Around 250 million years ago, 700 species of reptiles closely related to the modern-day crocodile roamed the earth, now new research reveals how a complex interplay between climate change, species competition and habitat can help explain why just 23 species of crocodile survive today.
Published Dishing the dirt on human evolution: Why scientific techniques matter in archaeology



Scientists should seek answers hidden in the dirt using proven and state-of-the-art archaeological science techniques to support new discoveries about human evolution following recent controversies at a cave site in Africa, says a group of international experts. Their recommendations follow claims published in June of this year that Homo naledi --a small-brained human species -- buried their dead in Rising Star Cave, South Africa, between 335,000 and 241,000 years ago, and may also have decorated the cave walls with engravings.
Published Unknown animals were leaving bird-like footprints in Late Triassic Southern Africa



Ancient animals were walking around on bird-like feet over 210 million years ago, according to a new study.
Published Landscape dynamics determine the evolution of biodiversity on Earth



A landmark study into the geological timescale distribution of sediment and nutrients over 500 million years shows that species biodiversity on Earth is driven by landscape dynamics.
Published Network of robots can successfully monitor pipes using acoustic wave sensors



An inspection design method and procedure by which mobile robots can inspect large pipe structures has been demonstrated with the successful inspection of multiple defects on a three-meter long steel pipe using guided acoustic wave sensors.
Published Earliest known European common hippopotamus fossil reveals their Middle Pleistocene dispersal



Modern hippos first dispersed in Europe during the Middle Pleistocene, according to a new study.
Published Curators and cavers: How a tip from a citizen scientist led to deep discoveries in Utah's caves



Scientists and colleagues from Utah's caving community have published the first research from their collaborative fieldwork effort deep in Utah's caves. The journal's feature article reveals why caves make such compelling research archives; what was uncovered in Boomerang Cave in northern Utah; why skeletal remains provide new access to hard-to-get data from the recent past; and offers a new zoological baseline for mammalian changes in an alpine community.
Published Trilobites rise from the ashes to reveal ancient map



Ten newly discovered species of trilobites, hidden for 490 million years in a little-studied part of Thailand, could be the missing pieces in an intricate puzzle of ancient world geography.
Published Looking for 'LUCA' and the timing of cellular evolution



LUCA, the 'last universal common ancestor' of all living organisms, lived 4.32 to at most 4.52 billion years ago. What LUCA looked like is unknown, but it must have been a cell with among others ribosomal proteins and an ATP synthase.
Published New percussion method to detect pipeline elbow erosion



An engineering research team is pioneering a new method, based on percussion, to detect pipeline elbow erosion to prevent economic losses, environmental pollution and other safety issues.
Published Like the phoenix, Australia's giant birds of prey rise again from limestone caves



Australia's only vulture, and a fearsome extinct eagle, are among the earliest recorded birds of prey from the Pleistocene period more than 50,000 years ago -- and now researchers are bringing them to 'life' again. Along with new scientific information, a bold new pictorial reconstruction of a newly named eagle and the only known Australian vulture will be unveiled at the World Heritage-listed Naracoorte Caves in South Australia's Limestone Coast this month.
Published Novel measurement technique for fluid mixing phenomena using selective color imaging method



A novel measurement technique has been developed to visualize the fluid flow and distribution within two droplets levitated and coalesced in space using fluorescence-emitting particles. This technique enabled the estimation of fluid motion within each droplet, thereby revealing the internal flow caused by surface vibration when the droplet merging promotes fluid mixing.
Published Research in Lake Superior reveals how sulfur might have cycled in Earth's ancient oceans



A scientists has sulfur on her mind. The yellow element is a vital macronutrient, and she's trying to understand how it cycles through the environment. Specifically, she's curious about the sulfur cycle in Earth's ancient ocean, some 3 billion years ago.
Published Radiocarbon dating meets Egyptology and Biblical accounts in the city of Gezer



New dates provide detailed insights into the timing of events in the ancient city of Gezer, according to a new study.
Published Birds set foot near South Pole in Early Cretaceous, Australian tracks show



The discovery of 27 avian footprints on the southern Australia coast -- dating back to the Early Cretaceous when Australia was still connected to Antarctica -- opens another window onto early avian evolution and possible migratory behavior.