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Categories: Anthropology: General, Physics: Optics
Published Neural networks made of light



Scientists propose a new way of implementing a neural network with an optical system which could make machine learning more sustainable in the future. In a new paper, the researchers have demonstrated a method much simpler than previous approaches.
Published 'A history of contact': Geneticists are rewriting the narrative of Neanderthals and other ancient humans



Using genomes from 2,000 living humans as well as three Neanderthals and one Denisovan, an international team mapped the gene flow between the hominin groups over the past quarter-million years.
Published Light-induced Meissner effect



Researchers have developed a new experiment capable of monitoring the magnetic properties of superconductors at very fast speeds.
Published Unveiling 1,200 years of human occupation in Canada's Arctic



A recent study provides new insights into ancient cultures in Canada's Arctic, focusing on Paleo-Inuit and Thule-Inuit peoples over thousands of years. Researchers detected human presence and settlements on Somerset Island, Nunavut, by analyzing sediment samples.
Published First ever 3D reconstruction of 52,000-year-old woolly mammoth chromosomes thanks to serendipitously freeze-dried skin



An international research team has assembled the genome and 3D chromosomal structures of a 52,000-year-old woolly mammoth -- the first time such a feat has been achieved for any ancient DNA sample. The fossilized chromosomes, which are around a million times longer than most ancient DNA fragments, provide insight into how the mammoth's genome was organized within its living cells and which genes were active within the skin tissue from which the DNA was extracted. This unprecedented level of structural detail was retained because the mammoth underwent freeze-drying shortly after it died, which meant that its DNA was preserved in a glass-like state.
Published High-speed electron camera uncovers a new 'light-twisting' behavior in an ultrathin material



Using an instrument for ultrafast electron diffraction (MeV-UED), researchers discovered how an ultrathin material can circularly polarize light. This discovery sets up a promising approach to manipulate light for applications in optoelectronic devices.
Published The plague may have caused the downfall of the Stone Age farmers



Ancient DNA from bones and teeth hints at a role of the plague in Stone Age population collapse. Contrary to previous beliefs, the plague may have diminished Europe's populations long before the major plague outbreaks of the Middle Ages, new research shows.
Published Archaeologists report earliest evidence for plant farming in east Africa



A trove of ancient plant remains excavated in Kenya helps explain the history of plant farming in equatorial eastern Africa, a region long thought to be important for early farming but where scant evidence from actual physical crops has been previously uncovered.
Published Moving from the visible to the infrared: Developing high quality nanocrystals



Awarded the 2023 Nobel Prize in Chemistry, quantum dots have a wide variety of applications ranging from displays and LED lights to chemical reaction catalysis and bioimaging. These semiconductor nanocrystals are so small -- on the order of nanometers -- that their properties, such as color, are size dependent, and they start to exhibit quantum properties. This technology has been really well developed, but only in the visible spectrum, leaving untapped opportunities for technologies in both the ultraviolet and infrared regions of the electromagnetic spectrum.
Published Implantable LED device uses light to treat deep-seated cancers



Certain types of light have proven to be an effective, minimally invasive treatment for cancers located on or near the skin when combined with a light-activated drug. But deep-seated cancers have been beyond the reach of light's therapeutic effects. To change this, engineers and scientists have devised a wireless LED device that can be implanted. This device, when combined with a light-sensitive dye, not only destroys cancer cells, but also mobilizes the immune system's cancer-targeting response.
Published Ancient dingo DNA shows modern dingoes share little ancestry with modern dog breeds



A study of ancient dingo DNA revealed that the distribution of modern dingoes across Australia, including those on K'gari (formerly Fraser Island), pre-dates European colonization and interventions like the dingo-proof fence.
Published Visualizing short-lived intermediate compounds produced during chemical reactions



Immobilizing small synthetic molecules inside protein crystals proves to be a promising avenue for studying intermediate compounds formed during chemical reactions, scientists report. By integrating this method with time-resolved serial femtosecond crystallography, they successfully visualized reaction dynamics and rapid structural changes occurring within reaction centers immobilized inside protein crystals. This innovative strategy holds significant potential for the intelligent design of drugs, catalysts, and functional materials.
Published Single atoms show their true color



A new technique reveals single atom misfits and could help design better semiconductors used in modern and future electronics.
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 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.