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May 15, 2024

Ancient stars could make elements with atomic masses greater than 260

Posted by in categories: cosmology, particle physics

The first stars of the universe were monstrous beasts. Comprised only of hydrogen and helium, they could be 300 times more massive than the sun. Within them, the first of the heavier elements were formed, then cast off into the cosmos at the end of their short lives. They were the seeds of all the stars and planets we see today. A new study published in Science suggests these ancient progenitors created more than just the natural elements.

Except for , , and a few traces of other light elements, all of the atoms we see around us were created through astrophysical processes, such as supernovae, collisions of neutron , and high-energy particle collisions. Together they created heavier elements up to Uranium-238, which is the heaviest naturally occurring element. Uranium is formed in supernova and neutron star collisions through what is known as the r-process, where neutrons are rapidly captured by atomic nuclei to become a heavier element. The r-process is complex, and there is still much we don’t understand about just how it occurs, or what its upper mass-limit might be. This new study, however, suggests that the r-process in the very first stars could have produced much heavier elements with atomic masses greater than 260.

The team looked at 42 stars in the Milky Way for which the elemental composition is well understood. Rather than simply looking for the presence of heavier elements, they looked at the relative abundances of elements across all the stars. They found that the abundance of some elements such as silver and rhodium doesn’t agree with the predicted abundance from known r-process nucleosynthesis. The data suggests that these elements are the decay remnants from much heavier nuclei of more than 260 atomic mass units.

May 15, 2024

Beta-decay measurements in mirror nuclei pin down the weak nuclear force

Posted by in category: particle physics

The Standard Model of Particle Physics is scientists’ best understanding of the forces that describe how subatomic particles interact. The Standard Model encompasses four forces: the strong nuclear force, the weak nuclear force, the electromagnetic force, and the gravitational force. All four forces govern the way our universe works. However, the weak nuclear force is exceptionally difficult to study as it is overshadowed by the much greater effects of the strong nuclear and electromagnetic forces.

May 15, 2024

The limits of nuclear stability change in stellar environments where temperatures reach billions of degrees Celsius

Posted by in category: futurism

New research is challenging the scientific status quo on the limits of the nuclear chart in hot stellar environments where temperatures reach billions of degrees Celsius.

The nuclear chart is a way to map out different kinds of atomic nuclei based on their number of protons and neutrons, and the “drip lines” can be viewed as the boundaries or edges of this map. Researchers from the University of Surrey and the University of Zagreb have found that these drip lines, which define the maximum number of protons and neutrons within a nucleus, change dynamically with temperature.

The findings challenge the view that drip lines and the number of bound nuclei are not sensitive to the temperature.

May 15, 2024

Scientists from Prague are expanding the possibilities of using RNA in gene medicine

Posted by in category: biotech/medical

Dr. Petr Cígler and his collaborators are working on refining molecular systems for transporting ribonucleic acid (RNA) molecules into cells. The question of how to effectively deliver RNA to a designated place in the body in order to silence a malfunctioning gene is one of the greatest challenges of the rapidly developing field of gene medicine.

May 15, 2024

A thousand times smaller than a grain of sand—glass sensors 3D-printed on optical fiber

Posted by in categories: innovation, internet

In a first for communications, researchers in Sweden 3D printed silica glass micro-optics on the tips of optic fibers—surfaces as small as the cross section of a human hair. The advance could enable faster internet and improved connectivity, as well as innovations like smaller sensors and imaging systems.

May 15, 2024

Multi-scale, nanomaterial-based ice inhibition platform enables full-cycle cryogenic protection for mouse oocytes

Posted by in categories: biotech/medical, chemistry, nanotechnology

Safe and high-quality fertility preservation is of growing significance for women in clinical trials. Current primary methods for cryopreserving human oocytes are slow freezing and vitrification, but existing techniques pose risks of biochemical toxicity and are restricted in large-scale clinical practice.

May 15, 2024

Uneven strain distribution induces detwinning in penta-twinned nanoparticles

Posted by in category: nanotechnology

Twinned nanoparticles have regions of clear symmetry that share the same crystal lattice, separated by a clear boundary. Changing the twin structure can affect the properties of the nanoparticles, which makes controlling twinning to create tailored nanomaterials an active area of research.

May 15, 2024

Physicists demonstrate first metro-area quantum computer network in Boston

Posted by in categories: computing, internet, quantum physics

It’s one thing to dream up a quantum internet that could send hacker-proof information around the world via photons superimposed in different quantum states. It’s quite another to physically show it’s possible.

May 15, 2024

A Groundbreaking Scientific Discovery Just Created the Instruction Manual for Light-Speed Travel

Posted by in categories: physics, space travel

In a first for warp drives, this research actually obeys the laws of physics.

May 15, 2024

SamuelSchmidgall/AgentClinic: Agent benchmark for medical diagnosis

Posted by in categories: biotech/medical, robotics/AI

From Stanford, Albert Einstein, & Johns Hopkins U: a multimodal agent benchmark to evaluate AI in simulated clinical environments.

From stanford, albert einstein, & johns hopkins U

AgentClinic: a multimodal agent benchmark to evaluate AI in simulated clinical environments abs: project page: code:

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