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Categories: Anthropology: General, Physics: Optics

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A novel catalysis scheme enables chemical reactions that were previously virtually impossible. The method is also environmentally friendly and does not require rare and precious metals. The researchers recorded the exact course of the catalysis in a kind of high-speed film. They did this using special lasers that can make processes visible that last only fractions of a billionth of a second. The results allow them to further optimize the catalyst.

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A new study finds that past changes in atmospheric CO2 and corresponding shifts in climate and vegetation played a key role in determining when and where early human species interbred.

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A new study finds that around 1.12 million years ago a massive cooling event in the North Atlantic and corresponding shifts in climate, vegetation and food resources disrupted early human occupation of Europe.

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Bringing ultrafast physics to structural biology has revealed the dance of molecular 'coherence' in unprecedented clarity.

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Researchers have developed an easy-to-build, low-cost 3D nanoprinting system that can create arbitrary 3D structures with extremely fine features. The new 3D nanoprinting technique is precise enough to print metamaterials as well as a variety of optical devices and components such as microlenses, micro-optical devices and metamaterials.

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Researchers have reported the first 3D measurements acquired with quantum ghost imaging. The new technique enables 3D imaging on a single photon level, yielding the lowest photon dose possible for any measurement.

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Using ancient DNA, researchers have determined cattle were imported from Africa to the Americas much earlier in the process of European colonization than documented. The first records of African cattle in the Americas date back to the 1800s, leading some historians to conclude that early colonists relied entirely on a small stock of European cattle initially shipped to the Caribbean Islands. DNA from archaeological specimens pushes the introduction of African cattle back by more than 100 years.

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Defects often limit the performance of devices such as light-emitting diodes (LEDs). The mechanisms by which defects annihilate charge carriers are well understood in materials that emit light at red or green wavelengths, but an explanation has been lacking for such loss in shorter-wavelength (blue or ultraviolet) emitters.

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Researchers have unveiled an artificial intelligence-based model for computational imaging and microscopy without training with experimental objects or real data. The team introduced a self-supervised AI model nicknamed GedankenNet that learns from physics laws and thought experiments. Informed only by the laws of physics that universally govern the propagation of electromagnetic waves in space, the researchers taught their AI model to reconstruct microscopic images using only random artificial holograms -- synthesized solely from 'imagination' without relying on any real-world experiments, actual sample resemblances or real data.

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A population genetics team recently identified the genetic relationship between over 40,000 23andMe users and a population of enslaved and free African Americans that lived in Catoctin Furnace, Maryland between 1776--1850. Over the course of this study, the researchers considered how best to inform descendants and other genetic relatives of their genetic connection to the site.

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A research team recently developed a stable artificial photocatalytic system that is more efficient than natural photosynthesis. The new system mimics a natural chloroplast to convert carbon dioxide in water into methane, a valuable fuel, very efficiently using light. This is a promising discovery, which could contribute to the goal of carbon neutrality.

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New research has achieved a significant breakthrough in color switching for nanocrystals, unlocking exciting possibilities for a simple, energy efficient display design and for tunable light sources needed in numerous technologies. The discovery also has potential applications in sensitive sensors for various substances, including biological and neuroscience uses, as well as advancements in quantum communication technologies. This nanomaterial breakthrough holds the promise of inspiring exciting innovations in the future.

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New films inspired by butterfly wings circumvent the heating effect usually experienced by colored objects absorbing light on a hot day. The new films could be used on the outside of buildings, vehicles and equipment to reduce the energy needed for cooling while preserving vivid color properties.

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The same fiber optic networks that provide internet can simultaneously act as earthquake sensors, as demonstrated in a new study.

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Engineers have developed HADAR, or heat-assisted detection and ranging.

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Theoreticians report that they found no evidence of any universal topological signatures after performing the first ab initio investigation of high harmonic generation from topological insulators.

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Earth is rapidly warming and scientists are developing a variety of approaches to reduce the effects of climate change. An astronomer has proposed a novel approach -- a solar shield to reduce the amount of sunlight hitting Earth, combined with a tethered, captured asteroid as a counterweight. Engineering studies using this approach could start now to create a workable design that could mitigate climate change within decades.

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Bringing protons up to speed with strong laser pulses -- this still young concept promises many advantages over conventional accelerators. For instance, it seems possible to build much more compact facilities. Prototypes to date, however, in which laser pulses are fired at ultra-thin metal foils, show weaknesses -- especially in the frequency with which they can accelerate protons. An international working group has tested a new technique: In this approach, frozen hydrogen acts as a 'target' for the laser pulses.

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Researchers have developed a new technique that vastly improves readings of protein-to-ligand interactions through Raman spectroscopy.

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Researchers have developed a pioneering technological solution that counterfeiters have no response to.