Diseases, Conditions, Syndromes

COVID-19: Distancing and masks are not enough

Wear a mask, keep your distance, avoid crowds—these are the common recommendations to contain the COVID-19 epidemic. However, the scientific foundations on which these recommendations are based are decades old and no longer ...

Psychology & Psychiatry

New cause of chronic stress identified in the brain

In an international collaboration between MedUni Vienna, Semmelweis University in Budapest, the Karolinska Institute in Stockholm and Yale University, researchers have identified a new process in the brain that is responsible ...

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.

Autism spectrum disorders

High levels of estrogen in the womb linked to autism

Scientist have identified a link between exposure to high levels of oestrogen sex hormones in the womb and the likelihood of developing autism. The findings are published today in the journal Molecular Psychiatry.

Pediatrics

Delaying newborn baths increases rates of breastfeeding

While it has been standard practice for decades to whisk newborns off to a bath within the first few hours of their birth, a new Cleveland Clinic study found that waiting to bathe a healthy newborn 12 or more hours after ...

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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