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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 27, 2026
Feb. 27, 2026 Researchers at Nagoya University have created a more efficient iron-based photocatalyst that could reduce the need for rare and expensive metals in advanced chemistry. Unlike earlier designs, the new catalyst uses far fewer costly chiral ligands ...
Feb. 27, 2026 Scientists have unveiled a breakthrough way to turn natural gas—long burned as fuel—into valuable chemical building blocks for medicines and other high-demand products. By designing a clever iron-based catalyst powered by LED light, researchers ...
Feb. 27, 2026 Heart disease is on track to tighten its grip on American women. New projections from the American Heart Association warn that over the next 25 years, cardiovascular disease will rise sharply, driven ...
Feb. 26, 2026 “Forever chemicals” known as PFAS have quietly infiltrated everything from nonstick pans to food packaging—and now new research suggests some of them may be speeding up the aging process itself. In a nationally representative U.S. study, two ...
Feb. 26, 2026 A massive study of more than 270,000 people has uncovered a surprising link between a common amino acid and how long men live. Researchers found that higher levels of tyrosine—an amino acid found in protein-rich foods and often marketed as a ...
Feb. 26, 2026 Biomolecular condensates were long believed to be simple liquid blobs inside cells. Researchers have now uncovered that some are actually supported by fine protein filaments forming an internal ...
Feb. 26, 2026 Worrying about getting older—especially fearing future health problems—may actually speed up aging at the cellular level, according to new research from NYU. In a study of more than 700 women, those who felt more anxious about aging showed signs ...
Feb. 26, 2026 Popular acid reflux drugs such as Prilosec, Nexium, and Protonix may carry hidden risks when taken long term. A new study found that extended use disrupted iron and calcium levels in rats, changes associated with anemia and osteoporosis risk. ...
Feb. 26, 2026 Avoiding meat might slightly lower the odds of reaching 100 — but only for frail, underweight seniors. In very old age, staying strong and maintaining muscle matters more than long-term disease prevention. Older adults who included fish, eggs, or ...
Feb. 26, 2026 A shingles shot might do more than prevent a painful rash — it could actually help slow down the aging process. In a large national study of more than 3,800 Americans age 70 and older, those who received the shingles vaccine showed slower ...
Feb. 25, 2026 A gel-like sugar coating on immune cells has been found to play a starring role in psoriasis. Researchers discovered that immune cells shed this outer layer to help them exit the bloodstream and enter inflamed skin. This challenges the long-held ...
Feb. 25, 2026 A sweeping new analysis of the evidence suggests that exercise therapy — long promoted as a first-line treatment for osteoarthritis — may offer only small and short-lived relief, and in some cases might be no better than doing nothing at all. ...
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Feb. 25, 2026 Eating nothing but oatmeal for just two days might sound extreme, but it delivered a striking payoff in a new clinical trial. People with metabolic syndrome who followed a short, calorie-reduced ...
Feb. 25, 2026 Scientists have zeroed in on a critical weak spot behind a rare but devastating brain autoimmune disorder often known as “Brain on Fire.” The disease strikes when the immune system attacks NMDA ...
Feb. 25, 2026 A weeklong, high-intensity version of TMS may work nearly as well as the standard six-week treatment for depression. In a UCLA study, patients who received five sessions a day for five days ...
Feb. 25, 2026 Researchers have detected microplastics in nearly all prostate cancer tumors examined in a new study. Tumor tissue contained about 2.5 times more plastic than nearby healthy prostate tissue. ...
Feb. 24, 2026 Subtle changes in brain blood flow and oxygen use are closely linked to hallmark signs of Alzheimer’s, including amyloid plaques and memory-related brain shrinkage. Simple, noninvasive scans may ...
Feb. 24, 2026 Researchers are engineering bacteria to invade tumors and consume them from the inside. Because tumor cores lack oxygen, they’re the perfect breeding ground for these microbes. The team added a ...
Feb. 24, 2026 A sweeping nationwide study has found that U.S. counties located closer to operating nuclear power plants have higher cancer death rates than those farther away. Researchers analyzed data from every ...
Feb. 23, 2026 Training harder may do more than build muscle—it could transform your gut. Researchers found that intense workouts change the balance of bacteria and important compounds in athletes’ digestive ...
Feb. 23, 2026 A UCLA study in mice reveals that aging muscle stem cells accumulate a protein that slows repair but boosts survival. This protein, NDRG1, acts like a brake, preventing cells from activating quickly ...
Feb. 23, 2026 People whose sugar intake was restricted before birth and in early childhood had markedly lower rates of heart disease later in life. Compared to those never exposed to rationing, their risks of ...