News tagged with heat

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Stress could help activate brown fat

Mild stress stimulates the activity and heat production by brown fat associated with raised cortisol, according to a study published today in Experimental Physiology.

Feb 09, 2016
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Take care in the bitter cold

(HealthDay)—As frigid temperatures send much of the northern half of the United States into a deep freeze, doctors say people need to take steps to avoid dangerous drops in body temperature, or hypothermia.

Jan 19, 2016
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Targeting HIV in semen to shut down AIDS

There may be two new ways to fight AIDS—using a heat shock protein or a small molecule - to attack fibrils in semen associated with the human immunodeficiency virus (HIV) during the initial phases of infection, according ...

Aug 18, 2015
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Heat

In physics and thermodynamics, heat is the process of energy transfer from one body or system to another due to a difference in temperature. In thermodynamics, the quantity TdS is used as a representative measure of the (inexact) heat differential δQ, which is the absolute temperature of an object multiplied by the differential quantity of a system's entropy measured at the boundary of the object.

A related term is thermal energy, loosely defined as the energy of a body that increases with its temperature. Heat is also loosely referred to as thermal energy, although many definitions require this thermal energy to actually be in the process of movement between one body and another to be technically called heat (otherwise, many sources prefer to continue to refer to the static quantity as "thermal energy"). Heat is also known as "Energy".

Energy transfer by heat can occur between objects by radiation, conduction and convection. Temperature is used as a measure of the internal energy or enthalpy, that is the level of elementary motion giving rise to heat transfer. Energy can only be transferred by heat between objects - or areas within an object - with different temperatures (as given by the zeroth law of thermodynamics). This transfer happens spontaneously only in the direction of the colder body (as per the second law of thermodynamics). The transfer of energy by heat from one object to another object with an equal or higher temperature can happen only with the aid of a heat pump, which does work.

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

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