Diseases, Conditions, Syndromes

Iran hits new COVID infection record for 2nd straight day

Iran recorded over 34,900 new coronavirus infections on Tuesday, setting the nation's single-day record for cases as vaccinations lag, public complacency deepens and the country's outbreak spirals further out of control.

Diseases, Conditions, Syndromes

Global warming may limit spread of dengue fever, new research finds

Infection with dengue virus makes mosquitoes more sensitive to warmer temperatures, according to new research led by Penn State researchers. The team also found that infection with the bacterium Wolbachia, which has recently ...

Health

3 tips for preventing heat stroke

As a primary care physician who often treats patients with heat-related illnesses, I know all too well how heat waves create spikes in hospitalizations and deaths related to "severe nonexertional hyperthermia," or what most ...

Health

At what temperature does the weather become a problem?

When extreme heat becomes more frequent and temperatures remain high for extended periods of time, as it is currently the case in Canada and the American Northwest, physiological stress increases in humans, animals and crops. ...

Pediatrics

Plastic drapes reduce hypothermia in premature babies

Most babies born prematurely or with health problems are quickly whisked away to the Neonatal Intensive Care Unit (NICU) where they might require assisted heating devices to regulate their temperature. A University of Houston ...

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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