Diseases, Conditions, Syndromes

Breakthrough paves way for new Lyme disease treatment

Virginia Tech biochemist Brandon Jutras has discovered the cellular component that contributes to Lyme arthritis, a debilitating and extremely painful condition that is the most common late stage symptom of Lyme disease.

Medical research

Engineered miniature kidneys come of age

In recent years, researchers have created mini-organs known as organoids in the culture dish that contain many of the cell types and complex microarchitectures found in human organs, such as the kidney, liver, intestine, ...

Alzheimer's disease & dementia

Midlife changes in Alzheimer's biomarkers may predict dementia

Studying brain scans and cerebrospinal fluid of healthy adults, scientists have shown that changes in key biomarkers of Alzheimer's disease during midlife may help identify those who will develop dementia years later, according ...

Medical research

Sperm crawl and collide on way to egg, researchers say

Scientists at the Universities of Birmingham and Warwick have shed new light on how sperm navigate the female reproductive tract, 'crawling' along the channel walls and swimming around corners; with frequent collisions.

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Fluid

In physics, a fluid is a substance that continually deforms (flows) under an applied shear stress, no matter how small. Fluids are a subset of the phases of matter and include liquids, gases, plasmas and, to some extent, plastic solids.

In common usage, "fluid" is often used as a synonym for "liquid", with no implication that gas could also be present. For example, "brake fluid" is hydraulic oil and will not perform its required function if there is gas in it. This colloquial usage of the term is also common in medicine and in nutrition ("take plenty of fluids").

Liquids form a free surface (that is, a surface not created by the container) while gases do not. The distinction between solids and fluid is not entirely obvious. The distinction is made by evaluating the viscosity of the substance. Silly Putty can be considered to behave like a solid or a fluid, depending on the time period over which it is observed. It is best described as a viscoelastic fluid. There are many examples of substances proving difficult to classify. A particularly interesting one is pitch, as demonstrated in the pitch drop experiment currently running at the University of Queensland.

This text uses material from Wikipedia, licensed under CC BY-SA