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Categories: Paleontology: General, Physics: Optics
Published Extinct humans survived on the Tibetan plateau for 160,000 years



Bone remains found in a Tibetan cave 3,280 m above sea level indicate an ancient group of humans survived here for many millennia.
Published Mighty floods of the Nile River during warmer and wetter climates



Global warming as well as recent droughts and floods threaten large populations along the Nile Valley. Sediment cores off the Nile mouth reveal insights into the effects and causes of heavy rainfall episodes about 9,000 years ago. That will help to prepare for weather extremes in a changing climate.
Published Using visible light to make pharmaceutical building blocks



Chemists have discovered a way to use visible light to synthesize a class of compounds particularly well suited for use in pharmaceuticals. The class of compounds, called azetidines, had been previously identified as a good candidate to build therapeutic drugs, but the compounds are difficult to produce in chemical reactions. Now, a team has developed a method to produce a specific class of azetidines called monocyclic azetidines using visible light and a photocatalyst.
Published Precise and less expensive 3D printing of complex, high-resolution structures



Researchers have developed a new two-photon polymerization technique that uses two lasers to 3D print complex high-resolution structures. The advance could make this 3D printing process less expensive, helping it find wider use in a variety of applications, from consumer electronics to the biomedical field.
Published Giant clams may hold the answers to making solar energy more efficient



Solar panel and biorefinery designers could learn a thing or two from iridescent giant clams living near tropical coral reefs, according to a new study. This is because giant clams have precise geometries -- dynamic, vertical columns of photosynthetic receptors covered by a thin, light-scattering layer -- that may just make them the most efficient solar energy systems on Earth.
Published Nuclear spectroscopy breakthrough could rewrite the fundamental constants of nature



Raising the energy state of an atom's nucleus using a laser, or exciting it, would enable development of the most accurate atomic clocks ever to exist. This has been hard to do because electrons, which surround the nucleus, react easily with light, increasing the amount of light needed to reach the nucleus. By causing the electrons to bond with fluorine in a transparent crystal, UCLA physicists have finally succeeded in exciting the neutrons in a thorium atom's nucleus using a moderate amount of laser light. This accomplishment means that measurements of time, gravity and other fields that are currently performed using atomic electrons can be made with orders of magnitude higher accuracy.
Published Optoelectronics gain spin control from chiral perovskites and III-V semiconductors



A research effort has made advances that could enable a broader range of currently unimagined optoelectronic devices.
Published Light targets cells for death and triggers immune response with laser precision



A new method of precisely targeting troublesome cells for death using light could unlock new understanding of and treatments for cancer and inflammatory diseases.
Published The evidence is mounting: humans were responsible for the extinction of large mammals



Human hunting, not climate change, played a decisive role in the extinction of large mammals over the last 50,000 years. This conclusion comes from researchers who reviewed over 300 scientific articles from many different fields of research.
Published Sixty-million-year-old grape seeds reveal how the death of the dinosaurs may have paved the way for grapes to spread



Scientists discovered the oldest fossil grapes in the Western Hemisphere, which help show how after the death of the dinosaurs, grapes spread across the world.
Published 'World record' for data transmission speed



Researchers have sent data at a record rate of 402 terabits per second using commercially available optical fiber. This beats their previous record, announced in March 2024, of 301 terabits or 301,000,000 megabits per second using a single, standard optical fiber.
Published New computational microscopy technique provides more direct route to crisp images



A new computational microscopy technique solves for true high-resolution images without the guesswork that has limited the precision of other techniques.
Published Light-controlled artificial maple seeds could monitor the environment even in hard-to-reach locations



Researchers have developed a tiny robot replicating the aerial dance of falling maple seeds. In the future, this robot could be used for real-time environmental monitoring or delivery of small samples even in inaccessible terrain such as deserts, mountains or cliffs, or the open sea. This technology could be a game changer for fields such as search-and-rescue, endangered species studies, or infrastructure monitoring.
Published Ammonites' fate sealed by meteor strike that wiped out dinosaurs



Ammonites were not in decline before their extinction, scientists have found.
Published Last surviving woolly mammoths were inbred but not doomed to extinction



The last population of woolly mammoths was isolated on Wrangel Island off the coast of Siberia 10,000 years ago, when sea levels rose and cut the mountainous island off from the mainland. A new genomic analysis reveals that the isolated mammoths, who lived on the island for the subsequent 6,000 years, originated from at most 8 individuals but grew to 200--300 individuals within 20 generations. The researchers report that the Wrangel Island mammoths' genomes showed signs of inbreeding and low genetic diversity but not to the extent that it can explain their ultimate (and mysterious) extinction.
Published Common plastics could passively cool and heat buildings with the seasons



By restricting radiant heat flows between buildings and their environment to specific wavelengths, coatings engineered from common materials can achieve energy savings and thermal comfort that goes beyond what traditional building envelopes can achieve.
Published Prehistoric 'Pompeii' discovered: Most pristine trilobite fossils ever found shake up scientific understanding of the long extinct group



Researchers have described some of the best-preserved three-dimensional trilobite fossils ever discovered. The fossils, which are more than 500 million years old, were collected in the High Atlas of Morocco and are being referred to by scientists as 'Pompeii' trilobites due to their remarkable preservation in ash.
Published Why the harsh Snowball Earth kick-started our earliest multicellular ancestors



Why did multicellularity arise? Solving that mystery may help pinpoint life on other planets and explain the vast diversity and complexity seen on Earth today, from sea sponges to redwoods to human society. A new article shows how specific physical conditions -- especially ocean viscosity and resource deprivation -- during the global glaciation period known as Snowball Earth could have driven eukaryotes to turn multicellular.
Published Solar technology: Innovative light-harvesting system works very efficiently



Researchers are reporting progress on the road to more efficient utilization of solar energy: They have developed an innovative light-harvesting system.
Published A chip-scale Titanium-sapphire laser



With a single leap from tabletop to the microscale, engineers have produced the world's first practical Titanium-sapphire laser on a chip, democratizing a once-exclusive technology.