How cells 'eat' their own fluid components

Autophagy is a fundamental cellular process by which cells capture and degrade their own dysfunctional or superfluous components for degradation and recycling. Recent research has revealed that phase separated droplets have ...

Simple bioreactor makes 'gut check' more practical

Rice University and Baylor College of Medicine researchers have found a way to mimic conditions in intestines, giving them a mechanical model for the real-time growth of bacterial infections.

Masks block 99.9% of large COVID-linked droplets: study

Face masks reduce the risk of spreading large COVID-linked droplets when speaking or coughing by up to 99.9 percent, according to a lab experiment with mechanical mannequins and human subjects, researchers said Wednesday.

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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