Lifeboat Foundation

Brown dwarfs are curious celestial bodies that appear to straddle the mass divide between stars and planets. Often referred to as “failed stars,” brown dwarfs form in isolation from a collapsing cloud of gas and dust like a star.

However, while fully-fledged stars continue to gather material from the gas and dust cloud that births them, brown dwarfs are less successful at this mass harvesting. As a result, they don’t reach the masses of the smallest stars and can’t trigger the process that defines main sequence stars, like our sun.

Dwarf galaxies like the SMC are often un-evolved when it comes to their chemistry because their history of star formation isn’t very extensive, so they haven’t had a chance to build up many heavy elements, such as carbon, nitrogen, oxygen, silicon or iron. NGC 346, for instance, contains about 10% the abundance of heavy elements that star-forming regions in our Milky Way galaxy have. This makes clusters such as NGC 346 great proxies for studying conditions akin to those found in the early universe.

NGC 346 is still forming lots of stars, and JWST found that many of the young ones, with ages of 20 to 30 million years, still possess planet-forming disks around them. Their existence confounds expectations.

“With Webb, we have a strong confirmation of what we saw with Hubble, and we must rethink how we create computer models for planet formation and early evolution in the young universe,” said Guido De Marchi of the European Space Research and Technology Centre (ESTEC) in the Netherlands, who led the research.

Scientists plan to borrow nature’s tools to develop and study fungal compounds further, which could lead to the development of new drugs.

Correctly quantifying mass is more important than you think.

Almost 300 binary mergers have been detected so far, indicated by their passing gravitational waves. These measurements from the world’s gravitational wave observatories put constraints on the masses and spins of the merging objects such as black holes and neutron stars, and in turn this information is being used to better understand the evolution of massive stars.

Thus far, these models predict a paucity of black hole binary pairs where each black hole has around 10 to 15 times the mass of the sun. This “dip or mass gap” in the mass range where black holes seldom form depends on assumptions made in the models; in particular, the ratio of the two masses in the binary.

Now a new study of the distribution of the masses of existing black holes in binaries finds no evidence for such a dip as gleaned from the gravitational waves that have been detected to date. The work is published in The Astrophysical Journal.

An investigational therapy is demonstrating preclinical promise against non-Hodgkin lymphoma by boosting natural killer cells and efficiently annihilating the malignancy without toxicity to the patient, a team of cancer biologists in France has found.

The emerging therapy is for B cell non-Hodgkin lymphoma, the most common form of lymphoma worldwide. Current therapies target the CD20⁺ protein on the surface of cancerous B cells but with limited efficacy. A newly developed antibody-based molecule targets B-non-Hodgkin lymphoma by engaging natural killer cells, warriors of the immune system. The experimental therapeutic is expected to help patients whose disease rebounds and is difficult to treat.

“Non-Hodgkin lymphoma is the most frequent hematological malignancy in humans, comprising nearly 3% of all cancer diagnoses and oncology-related mortalities,” writes Dr. Olivier Demaria, lead author of the research published in Science Immunology.

Researchers at Rice University have made a meaningful advance in the simulation of molecular electron transfer—a fundamental process underpinning countless physical, chemical and biological processes. The study, published in Science Advances, details the use of a trapped-ion quantum simulator to model electron transfer dynamics with unprecedented tunability, unlocking new opportunities for scientific exploration in fields ranging from molecular electronics to photosynthesis.

Electron transfer, critical to processes such as cellular respiration and energy harvesting in plants, has long posed challenges to scientists due to the complex quantum interactions involved. Current computational techniques often fall short of capturing the full scope of these processes. The multidisciplinary team at Rice, including physicists, chemists and biologists, addressed these challenges by creating a programmable quantum system capable of independently controlling the key factors in electron transfer: donor-acceptor energy gaps, electronic and vibronic couplings and environmental dissipation.

Using an ion crystal trapped in a vacuum system and manipulated by laser light, the researchers demonstrated the ability to simulate real-time spin dynamics and measure transfer rates across a range of conditions. The findings not only validate key theories of quantum mechanics but also pave the way for novel insights into light-harvesting systems and molecular devices.

Reliably measuring the polarization state of light is crucial for various technological applications, ranging from optical communication to biomedical imaging. Yet conventional polarimeters are made of bulky components, which makes them difficult to reduce in size and limits their widespread adoption.

Researchers at the Shanghai Institute of Technical Physics (SITP) of the Chinese Academy of Sciences and other institutes recently developed an on-chip full-Stokes polarimeter that could be easier to deploy on a large scale. Their device, presented in a paper in Nature Electronics, is based on optoelectronic polarization eigenvectors, mathematical equations that represent the linear relationship between the incident Stokes vector and a detector’s photocurrent.

“This work was driven by the growing demand for compact, high-performance polarization analysis devices in optoelectronics,” Jing Zhou, corresponding author of the paper, told Phys.org. “Traditional polarimeters, which rely on discrete bulky optical components, present significant challenges to miniaturization and limit their broader applicability. Our main goal is to develop an on-chip solution capable of direct electrical readout to reconstruct full-Stokes polarization states.”

Colloidal gels are complex systems made up of microscopic particles dispersed in a liquid, ultimately producing a semi-solid network. These materials have unique and advantageous properties that can be tuned using external forces, which have been the focus of various physics studies.

Researchers at University of Copenhagen in Denmark and the UGC-DAE Consortium for Scientific Research in India recently ran simulations and performed analyses aimed at understanding how the injection of active particles, such as swimming bacteria, would influence colloidal gels.

Their paper, published in Physical Review Letters, shows that active particles can influence the structure of 3D colloidal gels, kneading them into porous and denser structures.