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We are not alone: Our sun escaped together with stellar ‘twins’ from galaxy center

Researchers have uncovered evidence for our sun joining a mass migration of similar “twins” leaving the core regions of our galaxy, 4 to 6 billion years ago. The team created and studied an unprecedentedly accurate catalog of stars and their properties using data from the European Space Agency’s Gaia satellite. Their discovery sheds light on the evolution of our galaxy, particularly the development of the rotating bar-like structure at its center.

While archaeology on Earth studies the human past, galactic archaeology traces the vast journey of stars and galaxies. For example, scientists know that our sun was born around 4.6 billion years ago, more than 10,000 light years closer to the center of the Milky Way than we are today.

While studies of the composition of stars support this theory, this has long proven a conundrum for scientists. Observations reveal an enormous bar-like structure at our galactic center which creates a “corotation barrier,” which makes it difficult for stars to escape so far from the center.

Secondary bile acids as immune and metabolic mediators

The human liver makes two primary bile acids that are cholesterol derivates, while, intestinal microbiota is the source of hundreds of secondary bile acids and microbially conjugated bile acids.

A dysbiotic microbiota releases altered quantities and varieties of secondary bile acids, which contribute to intestinal and systemic immune dysregulation.

In this review the authors discuss recent advances in secondary bile acids, the intestinal microbiota generating them, and their role in immune disorders. sciencenewshighlights ScienceMission https://sciencemission.com/Secondary-bile-acids


Bile acids are cholesterol derivatives, generated by the coordinated intervention of human and bacterial genes, functioning as endogenous ligands for multiple transcription factors and receptors throughout the body. While only two primary bile acids are generated by the human liver, the intestinal microbiota is the source of hundreds of secondary bile acids and microbially conjugated bile acids. Secondary bile acids regulate immune function throughout the body, promote the conversion of thyroid hormone, and regulate energy expenditure in muscle and adipose tissues, ultimately contributing to the beneficial effects of calorie restriction on human health and longevity. Here, we discuss recent advances in our understanding of secondary bile acids, the intestinal microbiota generating them, and their role in immune disorders.

Diltiazem With Blood Thinners Tied to Bleeding Risk

Among patients with atrial fibrillation (AF) who initiated apixaban or rivaroxaban, the use of diltiazem was associated with a higher risk for serious bleeding complications than the use of metoprolol. The risk for bleeding was particularly elevated in patients who received diltiazem doses exceeding 120 mg daily.


Patients with atrial fibrillation who use diltiazem combined with apixaban or rivaroxaban face an increased risk for serious bleeding events compared with those who use metoprolol.

Human brain and AI speech recognition decode speech in similar step-by-step stages, study finds

Over the past decades, computer scientists have developed numerous artificial intelligence (AI) systems that can process human speech in different languages. The extent to which these models replicate the brain processes via which humans understand spoken language, however, has not yet been clearly determined.

Researchers at Columbia University, IBM Research and the Feinstein Institutes for Medical Research recently carried out a study aimed at comparing how automatic speech recognition (ASR) systems and the human brain decode speech. Their findings, published in Nature Machine Intelligence, suggest that activity in specific brain regions while people make sense of spoken language corresponds to specific stages in the processing of speech by AI models.

“The core mystery we wanted to solve is how the human brain performs the incredible computational feat of turning raw acoustic vibrations, the sounds of speech, into discrete linguistic meaning,” Nima Mesgarani, senior author of the paper, told Tech Xplore. “We now have AI systems that match human performance in transcribing speech, but we didn’t know if they were reaching those solutions independently or if they had converged on the same strategy as our biology.”

Molecular mechanisms of insulin resistance

1. Insulin stimulates tyrosine phosphorylation of the insulin receptor and of an endogenous substrate of approximately 185 kDa (insulin receptor substrate 1 or IRS-1). IRS-1 fulfills the criteria of a direct substrate of the insulin receptor, and tyrosine phosphorylation of IRS-1 leads to another step in insulin action, i.e., an association of phosphorylated IRS-1 with the enzyme PI3-kinase activating this enzyme. Using antipeptide antibodies to insulin receptor, to IRS-1 and to PI 3-kinase together with anti-phosphotyrosine antibodies it is possible to study insulin-stimulated insulin receptor phosphorylation, IRS-1 phosphorylation and the association/activation of IRS-1/PI 3-kinase. 2. In this review we describe alterations in these three early steps of insulin action after binding in animal models of insulin resistance, i.e., streptozotocin-induced diabetes (STZ diabetes), fasting, spontaneously hypertensive rats, the ob/ob mice, dexamethasone-treated rats, and the chronic effect of insulin on Fao cells in culture. 3. In states of insulin resistance with hypoinsulinemia (STZ diabetes and fasting) there is an increase in these early steps of insulin action. In animal models of insulin resistance with hyperinsulinemia there is a decrease in these steps of insulin action, indicating molecular post-receptor defects. Since we could reproduce the decrease in these three early steps of insulin action in cells in culture by chronic treatment with insulin, we postulate that these defects may be a consequence of the hyperinsulinemia of these animals.

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Targeted Remediation of the Ipsilesional Arm in Chronic Stroke: A Randomized Clinical Trial

Among patients with chronic stroke and severe contralesional impairment, targeted ipsilesional arm training supported significant and sustained improvements in ipsilesional motor performance vs best practice therapy.


Importance Ipsilesional upper-limb motor deficits after stroke are functionally important yet largely neglected in rehabilitation. Remediation may improve motor outcomes in individuals with severe contralesional arm hemiparesis.

Objective To determine whether training of the ipsilesional arm improves motor performance in chronic stroke with severe contralesional impairment and significant ipsilesional arm motor deficits.

Design, Setting, and Participants This 2-site, parallel-group randomized clinical trial with blinded outcome assessment was conducted from February 2019 to August 2024, with follow-up through 6 months posttreatment. Data analysis was performed from August 2024 through August 2025. The trial was conducted at outpatient research laboratories at Penn State College of Medicine and the University of Southern California among adults with radiologically confirmed unilateral middle cerebral artery stroke, severe contralesional upper-extremity impairment (Fugl-Meyer score ≤28), and ipsilesional motor deficits. Participants were randomly assigned with equal probability to 2 treatment groups and stratified by sex.

Light-guided evolution creates proteins that can switch, sense, and compute

Researchers have created a method called optovolution that uses light to guide the evolution of proteins with dynamic behaviors. By engineering yeast cells so their survival depended on proteins switching states at the right time, scientists could rapidly select the best-performing variants. The technique produced new light-sensitive proteins that respond to different colors and improved optogenetic systems. It even evolved a protein that behaves like a tiny logic gate, activating genes only when two signals are present.

Atom-thin material could help solve chip manufacturing problem

Making computer chips smaller is not just about better design. It also depends on a critical step in manufacturing called patterning, where nanoscale structures are carved into materials to form the circuits inside everything from smartphones to advanced sensors.

To create these patterns, engineers use a hard mask, a thin, durable material layer that protects selected regions while the exposed areas are etched away.

“As chips get smaller, the manufacturing process becomes much more demanding,” said Saptarshi Das, Penn State Ackley Professor of Engineering Science and professor of engineering science and mechanics. “The mask used to define these patterns must survive extremely harsh processing conditions. If the mask degrades, the patterns cannot be transferred reliably.”

Brain-inspired device could lead to faster, more energy-efficient AI hardware

A team led by engineers at the University of California San Diego has developed a new brain-inspired hardware platform that could help computer hardware keep pace with the explosive growth of artificial intelligence. By combining memory and computation on the same chip—and allowing its components to interact collectively like neurons in the brain—the brain-inspired platform improved the speed, accuracy, and energy efficiency of pattern recognition in two simulated tasks: recognizing spoken digits and detecting epileptic seizures early from brain-wave recordings.

The approach could lead to the development of compact, energy-efficient hardware for smaller AI systems such as those used in wearable health monitors, smart sensors, and other autonomous devices.

The work, published on March 9 in Nature Nanotechnology, falls within the field of neuromorphic computing, which aims to build machines that mimic how the brain processes information. The researchers emphasize that the technology is brain-inspired, rather than brain-like; it draws ideas from how neural networks interact but does not attempt to replicate the brain itself.

Scientists create slippery nanopores that supercharge blue energy

Scientists have found a way to significantly boost “blue energy,” which generates electricity from the mixing of saltwater and freshwater. By coating nanopores with lipid molecules that create a friction-reducing water layer, they enabled ions to pass through much more efficiently while keeping the process highly selective. Their prototype membrane produced about two to three times more power than current technologies. The discovery could help bring osmotic energy closer to becoming a practical renewable power source.

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