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 ...

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 ...

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.

Neuroscience

Sleep problems may be early sign of Alzheimer's

Poor sleep may be a sign that people who are otherwise healthy may be more at risk of developing Alzheimer's disease later in life than people who do not have sleep problems, according to a study published in the July 5, ...

Alzheimer's disease & dementia

Minimally invasive blood test for Alzheimer's disease

Scientists from Japan and Australia have teamed up to develop and validate a blood test for Alzheimer's disease, with the potential to massively ramp up the pace of Alzheimer's disease drug trials.

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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