Neuroscience

Distinctive inflammatory signature found in a genetic form of ALS

Amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig's disease, is a neurodegenerative disease that strikes nearly 5,000 people in the U.S. every year. About 10% of ALS cases are inherited or familial, often caused ...

Neuroscience

Investigators examine brain tests of patients with COVID-19

In a Journal of Neuroimaging analysis of data obtained from 193 patients with COVID-19 who had brain and/or spine imaging and a lumbar puncture because of neurologic symptoms, investigators found that imaging results were ...

Medical research

New algorithm for the diagnostics of dementia

Researchers from the University of Eastern Finland and the University of Oulu in collaboration with an international team have created a new diagnostic biomarker-based algorithm for the diagnostics of dementia. The team is ...

Diseases, Conditions, Syndromes

Containing the coronavirus effects on the nervous system

A number of studies have shown that human coronaviruses, including SARS-CoV-2 which causes COVID-19, appear to attack neurons and the nervous system in vulnerable populations. This neuroinvasion through the nasal cavity leads ...

Diseases, Conditions, Syndromes

Innovative blood test based on infrared light

The molecular composition of the blood provides information regarding one's state of health, and may be compared to an individual fingerprint. In principle, changes in the constituents of blood can serve as early signs of ...

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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