Reference Terms
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Transmission electron microscopy
Transmission electron microscopy (TEM) is an imaging technique whereby a beam of electrons is focused onto a specimen causing an enlarged version to appear on a fluorescent screen or layer of photographic film, or to be detected by a CCD camera. In the past, light microscopes have been used mostly for imaging due to their relative ease of use. However, the maximum resolution that one can image is determined by the wavelength of the photons that are being used to probe the sample. In the early days of microscopy nothing smaller than the wavelength being used could be resolved, whereas nowadays the law of RESOLFT sets the limit for optical microscopes employing such concepts.
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Health & Medicine News
July 29, 2025
July 29, 2025 — A global study of over 88,000 adults reveals that poor sleep habits—like going to bed inconsistently or having disrupted circadian rhythms—are tied to dramatically higher risks for dozens of diseases, including liver cirrhosis and gangrene. ...
July 29, 2025 — Scientists at Columbia Engineering have developed an injectable hydrogel made from yogurt-derived extracellular vesicles (EVs) that could revolutionize regenerative medicine. These EVs serve both as healing agents and as structural components, ...
July 29, 2025 — Fast walking, even just 15 minutes a day, can dramatically reduce the risk of death, especially from heart disease, according to a large study involving nearly 80,000 low-income and predominantly Black Americans in the South. The findings not only ...
July 29, 2025 — A mysterious gut hormone may be behind many cases of chronic diarrhea, especially in people with undiagnosed bile acid malabsorption, a condition often mistaken for irritable bowel syndrome. Researchers from the University of Cambridge identified ...
July 28, 2025 — Walking just a bit faster could be the key to aging well. Researchers found that older adults who upped their walking pace by just 14 steps per minute significantly improved their physical abilities—even those who were already frail. A new, ...
July 28, 2025 — Eggs are finally being vindicated after decades of cholesterol-related blame. New research from the University of South Australia reveals that eggs, despite their cholesterol content, aren't the dietary villains they've long been made out to be. ...
July 28, 2025 — Over-the-counter (OTC) products like St John’s Wort and omega-3s have long been touted for helping with depression, but new research reveals that 64 different OTC products have been tested in ...
July 28, 2025 — Many people with dementia endure long delays often over 3 years before receiving a diagnosis, with even longer waits for younger patients. A global review of over 30,000 cases reveals that age, dementia type, and systemic healthcare issues like ...
July 27, 2025 — A team of scientists has developed a remarkable new approach to modeling how cells behave over time—using a digital "forecast" much like predicting the weather. By combining patient genomics with a groundbreaking plain-language “hypothesis ...
July 27, 2025 — Between 2020 and 2024, COVID-19 vaccines saved 2.5 million lives globally, preventing one death for every 5,400 doses. A groundbreaking worldwide study led by researchers from Università Cattolica and Stanford University reveals that most lives ...
July 27, 2025 — Scientists at UCSF have uncovered how certain immune cells in the brain, called microglia, can effectively digest toxic amyloid beta plaques that cause Alzheimer’s. They identified a key receptor, ...
July 27, 2025 — Scientists at the University of Toronto have developed a new non-stick material that rivals the performance of traditional PFAS-based coatings while using only minimal amounts of these controversial ...
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July 27, 2025 — Air pollution isn't just bad for your lungs—it may be eroding your brain. In a sweeping review covering nearly 30 million people, researchers found ...
July 27, 2025 — Walking 7000 steps a day may be just as powerful as hitting the much-hyped 10,000-step goal when it comes to reducing the risk of early death and disease. A sweeping global review of 57 studies shows ...
July 26, 2025 — A groundbreaking study has revealed that the mass administration of ivermectin—a drug once known for treating river blindness and scabies—can significantly reduce malaria transmission when used ...
July 25, 2025 — Fermenting stevia with a banana leaf-derived probiotic turns it into a powerful cancer-fighting agent that kills pancreatic cancer cells while sparing healthy ones. The secret lies in a metabolite ...
July 25, 2025 — What if we could predict obesity before it ever takes hold? A global team has created a genetic test that forecasts a child’s risk of adult obesity before age five—years before other factors kick ...
July 25, 2025 — A breakthrough AI system is revolutionizing cancer immunotherapy by enabling scientists to design protein-based keys that train a patient s immune cells to attack cancer with extreme precision. This ...
July 25, 2025 — Millipedes, often dismissed as creepy crawlies, may hold the secret to future painkillers and neurological drugs. Researchers at Virginia Tech discovered unique alkaloid compounds in the defensive ...
July 25, 2025 — A virus from humble black-eyed peas is showing extraordinary promise in the fight against cancer. Unlike other plant viruses, the cowpea mosaic virus (CPMV) can awaken the human immune system and ...
July 24, 2025 — A new study reveals that swapping a typical nighttime carbohydrate snack for pistachios may beneficially alter gut bacteria in people with prediabetes. Conducted by Penn State researchers, the ...
July 24, 2025 — Scientists at Princeton and the Simons Foundation have identified four biologically distinct subtypes of autism, using data from over 5,000 children ...