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Categories: Physics: Optics, Space: Structures and Features
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 Building materials for water-rich planets in the early solar system



Age data for certain classes of meteorite have made it possible to gain new findings on the origin of small water-rich astronomical bodies in the early solar system. These planetesimals continually supplied building materials for planets -- also for the Earth, whose original material contained little water. The Earth received its actual water through planetesimals, which emerged at low temperatures in the outer solar system, as shown by computational models carried out by an international research teach with participation by earth scientists.
Published Stench of a gas giant? Nearby exoplanet reeks of rotten eggs, and that's a good thing



An exoplanet infamous for its deadly weather has been hiding another bizarre feature -- it reeks of rotten eggs, according to a new study of data from the James Webb Space Telescope.
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 Fresh wind blows from historical supernova



A mysterious remnant from a rare type of supernova recorded in 1181 has been explained for the first time. Two white dwarf stars collided, creating a temporary 'guest star,' now labeled supernova (SN) 1181, which was recorded in historical documents in Japan and elsewhere in Asia. However, after the star dimmed, its location and structure remained a mystery until a team pinpointed its location in 2021. Now, through computer modeling and observational analysis, researchers have recreated the structure of the remnant white dwarf, a rare occurrence, explaining its double shock formation. They also discovered that high-speed stellar winds may have started blowing from its surface within just the past 20-30 years. This finding improves our understanding of the diversity of supernova explosions, and highlights the benefits of interdisciplinary research, combining history with modern astronomy to enable new discoveries about our galaxy.
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 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 '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 Tiny bright objects discovered at dawn of universe baffle scientists



A recent discovery by NASA's James Webb Space Telescope (JWST) confirmed that luminous, very red objects previously detected in the early universe upend conventional thinking about the origins and evolution of galaxies and their supermassive black holes.
Published Too many missing satellite galaxies found



Bringing us one step closer to solving the 'missing satellites problem,' researchers have discovered two new satellite galaxies.
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 The density difference of sub-Neptunes finally deciphered



The majority of stars in our galaxy are home to planets. The most abundant are the sub-Neptunes, planets between the size of Earth and Neptune. Calculating their density poses a problem for scientists: depending on the method used to measure their mass, two populations are highlighted, the dense and the less dense. Is this due to an observational bias or the physical existence of two distinct populations of sub-Neptunes? Recent work argues for the latter.
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.