Reference Terms
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Ultrasound
Ultrasound is sound with a frequency greater than the upper limit of human hearing, approximately 20 kilohertz (20,000 hertz). Some animals, such as dogs, dolphins, bats, and mice have an upper limit that is greater than that of the human ear and thus can hear ultrasound.
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Health & Medicine News
February 13, 2026
Feb. 13, 2026 Fish oil’s cancer-fighting reputation may hinge on a little-known gene. Researchers discovered that omega-3s like EPA and DHA help curb colorectal cancer only when the enzyme ALOX15 is present. Without it, fish oil sometimes increased tumor growth ...
Feb. 13, 2026 Scientists at Cedars-Sinai have uncovered a surprising repair system in the spinal cord that could open new doors for treating paralysis, stroke, and diseases like multiple sclerosis. They found that special support cells called astrocytes—located ...
Feb. 13, 2026 Microplastics and nanoplastics are now found everywhere on Earth, from ocean depths to agricultural soils and even inside the human body. Yet scientists still struggle to understand what these particles actually do once they enter living organisms. ...
Feb. 13, 2026 A low-fat vegan diet—without cutting calories or carbs—may help people with type 1 diabetes significantly reduce how much insulin they need, and how much they spend on it. In a new analysis published in BMC Nutrition, participants following the ...
Feb. 13, 2026 A robotic arm that moves too quickly can feel creepy. One that moves too slowly feels awkward and unhelpful. In a VR study, researchers found that AI-powered prosthetic arms were best accepted when they moved at a natural, human-like speed—about ...
Feb. 12, 2026 A protein called HIF1 may be the missing link behind painful tendon injuries like jumper’s knee and tennis elbow. Researchers showed that high levels of HIF1 actually cause harmful changes that make tendons brittle and prone to pain. In ...
Feb. 12, 2026 A newly identified protein may hold the key to rejuvenating aging brain cells. Researchers found that boosting DMTF1 can restore the ability of neural stem cells to regenerate, even when age-related damage has set in. Without it, these cells ...
Feb. 12, 2026 Swapping just an hour of TV a day for something more active could significantly lower the risk of developing major depression—especially in middle age. A large Dutch study tracking more than 65,000 adults over four years found that replacing 60 ...
Feb. 11, 2026 A six-week study from the University of Nottingham suggests that pairing fermented kefir with a diverse prebiotic fiber mix may deliver a powerful anti-inflammatory boost. This “synbiotic” combination outperformed omega-3 supplements and fiber ...
Feb. 11, 2026 A simple brain-training program that sharpens how quickly older adults process visual information may have a surprisingly powerful long-term payoff. In a major 20-year study of adults 65 and older, those who completed five to six weeks of adaptive ...
Feb. 11, 2026 A new clinical trial suggests that changing when you eat could make a meaningful difference for people living with Crohn’s disease. Researchers found that time-restricted feeding, a form of intermittent fasting that limits meals to an 8-hour daily ...
Feb. 11, 2026 Three major reviews commissioned by the World Health Organization find that GLP-1 drugs including tirzepatide (sold as Mounjaro and Zepbound), semaglutide (Ozempic and Wegovy), and liraglutide ...
Latest Headlines
updated 12:56 pm ET
Feb. 11, 2026 Depression in older adults may sometimes signal the early stages of Parkinson’s disease or Lewy body dementia. Researchers found that depression ...
Feb. 11, 2026 A cooler bedroom might be better for older sleepers than previously thought. Researchers found that keeping nighttime temperatures at 75°F reduced stress responses and helped the heart work more ...
Feb. 11, 2026 Blood vessels twist, branch, narrow, and balloon in ways that dramatically affect how blood flows — but most lab models have long treated them like straight pipes. Researchers at Texas A&M have now ...
Feb. 11, 2026 Why does the same virus barely faze one person while sending another to the hospital? New research shows the answer lies in a molecular record etched into our immune cells by both our genes and our ...
Feb. 10, 2026 Ultra-processed foods are everywhere in the American diet, and researchers are finding alarming consequences. Using national health data, scientists found that adults with the highest intake of these ...
Feb. 10, 2026 Scientists have uncovered a surprising way tumors turn the immune system to their advantage. Researchers at the University of Geneva found that neutrophils—normally frontline defenders against ...
Feb. 10, 2026 Human evolution has long been tied to growing brain size, and new research suggests prenatal hormones may have played a surprising role. By studying the relative lengths of index and ring fingers — ...
Feb. 10, 2026 Autism has long been thought of as a condition that mostly affects boys, but a massive study from Sweden suggests that idea may be misleading. Tracking nearly 3 million people over decades, ...
Feb. 10, 2026 A large U.S. study suggests that not getting enough lycopene—the antioxidant that gives tomatoes their red color—may seriously raise the risk of severe gum disease in older adults. Researchers ...
Feb. 10, 2026 A sweeping new review of ADHD treatments—drawing on more than 200 meta-analyses—cuts through years of mixed messaging and hype. To make sense of it all, researchers have launched an interactive, ...