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Categories: Ecology: Trees, Physics: Optics

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Highly reducing or oxidizing photocatalysts are a fundamental challenge in photochemistry. Only a few transition metal complexes with Earth-abundant metal ions have so far advanced to excited state oxidants, including chromium, iron, and cobalt. All these photocatalysts require high energy light for excitation and their oxidizing power has not yet been fully exploited. Furthermore, precious and hence expensive metals are the decisive ingredients in most cases. A team of researchers has now developed a new molecular system based on the element manganese. Manganese, as opposed to precious metals, is the third most abundant metal after iron and titanium and hence widely available and very cheap.

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A new technique can control a larger number of microscopic defects in a diamond. These defects can be used as qubits for quantum sensing applications, and being able to control a greater number of qubits would improve the sensitivity of such devices.

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The Greenland ice sheet lies thousands of miles from North America yet holds clues to the distant continent's environmental history. Nearly two miles thick in places, the ice sheet grows as snow drifts from the sky and builds up over time. But snow isn't the only thing carried in by air currents that swirl around the atmosphere, with microscopic pollen grains and pieces of ash mixing with snowfall and preserving records of the past in the ice. A new study examined these pollen grains and identified how eastern Canada's forests grew, retreated, and changed through time.

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Researchers have developed a spiral-shaped lens that maintains clear focus at different distances in varying light conditions. The new lens works much like progressive lenses used for vision correction but without the distortions typically seen with those lenses. It could help advance contact lens technologies, intraocular implants for cataracts and miniaturized imaging systems.

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Extreme events wipe out entire forests, dramatically eliminating complex ecosystems as well as local communities. Researchers have become quite familiar with such attention-grabbing events over the years. They know less, however, about the more common moderate-severity disturbances, such as relatively small fires, ice storms, and outbreaks of pests or pathogens.

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Researchers pioneer dynamic manipulation and the generation principles of trion at the nanoscale using tip-enhanced cavity-spectroscopy.

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Scientists completed several successful attempts to fire 28 kilojoules of laser energy at small capsules filled with deuterium and tritium fuel, causing the capsules to implode and produce a plasma hot enough to initiate fusion reactions between the fuel nuclei. These results demonstrate an effective 'spark plug' for direct-drive methods of inertial confinement fusion.

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Many people are familiar with facial recognition systems that unlock smartphones and game systems or allow access to our bank accounts online. But the current technology can require boxy projectors and lenses. Now, researchers report on a sleeker 3D surface imaging system with flatter, simplified optics. In proof-of-concept demonstrations, the new system recognized the face of Michelangelo's David just as well as an existing smartphone system.

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Researchers have succeeded in generating a logical qubit from a single light pulse that has the inherent capacity to correct errors.

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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.

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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.

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Researchers have gained new insights into the development of the light-induced ferroelectric state in SrTiO3. They exposed the material to mid-infrared and terahertz frequency laser pulses and found that the fluctuations of its atomic positions are reduced under these conditions. This may explain why the dipolar structure is more ordered than in equilibrium and why the laser pulses induce a ferroelectric state in the material.

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Researchers have discovered a change in what scientists already knew about global warming dynamics. It had been widely accepted since the 1950s that global temperature rises were not consistent throughout the day and night, with greater nighttime warming being observed. However, the recent study reveals a shift in dynamics: with greater daytime warming taking place since the 1990s. This shift means that the temperature difference between day and night is widening, potentially affecting all life on Earth.

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Researchers have successfully developed a new time-resolved atomic force microscopy (AFM) technique, integrating AFM with a unique laser technology. This method enables the measurement of ultrafast photoexcitation phenomena in both conductors and insulators, observed through changes in the forces between the sample and the AFM probe tip after an extremely short time irradiation of laser light. This advancement promises substantial contributions to the creation of new scientific and technological principles and fields.

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Researchers have developed a pioneering method to precisely manipulate ultrafast spin waves in antiferromagnetic materials using tailored light pulses.

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How is a beech leaf constructed? What determines the appearance of an asparagus? A new 'encyclopaedia' helps us learn more about the building blocks of plants. The encyclopaedia, probably the largest of its kind, could be used to improve targeted plant breeding efforts, to make them both more climate-resilient and more easily digestible.

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Plasmonics are unique light-matter interactions in the nanoscale regime. Now, a team of researchers has highlighted advances in shadow growth techniques for plasmonic materials, which have the potential to give rise to nanoparticles with diverse shapes and properties. They also introduce a method for large-scale production of nano-rotamers of magnesium with programmable polarization behavior, opening avenues for novel research applications.

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Scientists have developed a new system for imaging nanoparticles. It consists of a high-precision, short-wave infrared imaging technique capable of capturing the photoluminescence lifetimes of rare-earth doped nanoparticles in the micro- to millisecond range.

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Our built environment is aging and failing faster than we can maintain it. Recent building collapses and structural failures of roads and bridges are indicators of a problem that's likely to get worse, according to experts, because it's just not possible to inspect every crack, creak and crumble to parse dangerous signs of failure from normal wear and tear. In hopes of playing catch-up, researchers are trying to give robotic assistants the tools to help inspectors with the job.

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A new way of creating color uses the scattering of light of specific wavelengths around tiny, almost perfectly round silicon crystals. This development enables non-fading structural colors that do not depend on the viewing angle and can be printed. The material has a low environmental and biological impact and can be applied extremely thinly, promising significant weight improvements over conventional paints.