Body Temperature Changes: Significant alterations in temperature of the human body, above or below 98.6 degrees F. or 37 degrees C. when taken orally.Body Temperature: The measure of the level of heat of a human or animal.Body Temperature Regulation: The processes of heating and cooling that an organism uses to control its temperature.Temperature: The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.Thermography: Imaging the temperatures in a material, or in the body or an organ. Imaging is based on self-emanating infrared radiation (HEAT WAVES), or on changes in properties of the material or tissue that vary with temperature, such as ELASTICITY; MAGNETIC FIELD; or LUMINESCENCE.Skin Temperature: The TEMPERATURE at the outer surface of the body.Thermoreceptors: Cellular receptors which mediate the sense of temperature. Thermoreceptors in vertebrates are mostly located under the skin. In mammals there are separate types of thermoreceptors for cold and for warmth and NOCICEPTORS which detect cold or heat extreme enough to cause pain.Thermometers: Measuring instruments for determining the temperature of matter. Most thermometers used in the field of medicine are designed for measuring body temperature or for use in the clinical laboratory. (From UMDNS, 1999)Hot Temperature: Presence of warmth or heat or a temperature notably higher than an accustomed norm.Cold Temperature: An absence of warmth or heat or a temperature notably below an accustomed norm.Thermosensing: The sensation of cold, heat, coolness, and warmth as detected by THERMORECEPTORS.Thermometry: Measurement of the temperature of a material, or of the body or an organ by various temperature sensing devices which measure changes in properties of the material that vary with temperature, such as ELASTICITY; MAGNETIC FIELDS; or LUMINESCENCE.Fever: An abnormal elevation of body temperature, usually as a result of a pathologic process.Hypothermia: Lower than normal body temperature, especially in warm-blooded animals.Infrared Rays: That portion of the electromagnetic spectrum usually sensed as heat. Infrared wavelengths are longer than those of visible light, extending into the microwave frequencies. They are used therapeutically as heat, and also to warm food in restaurants.Telemetry: Transmission of the readings of instruments to a remote location by means of wires, radio waves, or other means. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Acclimatization: Adaptation to a new environment or to a change in the old.Thermal Conductivity: The heat flow across a surface per unit area per unit time, divided by the negative of the rate of change of temperature with distance in a direction perpendicular to the surface. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Tidal Waves: Water waves caused by the gravitational interactions between the EARTH; MOON; and SUN.Climate: The longterm manifestations of WEATHER. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Greenhouse Effect: The effect of GLOBAL WARMING and the resulting increase in world temperatures. The predicted health effects of such long-term climatic change include increased incidence of respiratory, water-borne, and vector-borne diseases.Seasons: Divisions of the year according to some regularly recurrent phenomena usually astronomical or climatic. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Heating: The application of heat to raise the temperature of the environment, ambient or local, or the systems for accomplishing this effect. It is distinguished from HEAT, the physical property and principle of physics.Hibernation: The dormant state in which some warm-blooded animal species pass the winter. It is characterized by narcosis and by sharp reduction in body temperature and metabolic activity and by a depression of vital signs.Climate Change: Any significant change in measures of climate (such as temperature, precipitation, or wind) lasting for an extended period (decades or longer). It may result from natural factors such as changes in the sun's intensity, natural processes within the climate system such as changes in ocean circulation, or human activities.Global Warming: Increase in the temperature of the atmosphere near the Earth's surface and in the troposphere, which can contribute to changes in global climate patterns.Cryotherapy: A form of therapy consisting in the local or general use of cold. The selective destruction of tissue by extreme cold or freezing is CRYOSURGERY. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Circadian Rhythm: The regular recurrence, in cycles of about 24 hours, of biological processes or activities, such as sensitivity to drugs and stimuli, hormone secretion, sleeping, and feeding.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Heat Stroke: A condition caused by the failure of body to dissipate heat in an excessively hot environment or during PHYSICAL EXERTION in a hot environment. Contrast to HEAT EXHAUSTION, the body temperature in heat stroke patient is dangerously high with red, hot skin accompanied by DELUSIONS; CONVULSIONS; or COMA. It can be a life-threatening emergency and is most common in infants and the elderly.Scrotum: A cutaneous pouch of skin containing the testicles and spermatic cords.Shivering: Involuntary contraction or twitching of the muscles. It is a physiologic method of heat production in man and other mammals.Humidity: A measure of the amount of WATER VAPOR in the air.Hyperthermia, Induced: Abnormally high temperature intentionally induced in living things regionally or whole body. It is most often induced by radiation (heat waves, infra-red), ultrasound, or drugs.Hypothermia, Induced: Abnormally low BODY TEMPERATURE that is intentionally induced in warm-blooded animals by artificial means. In humans, mild or moderate hypothermia has been used to reduce tissue damages, particularly after cardiac or spinal cord injuries and during subsequent surgeries.Visible Human Projects: Digital image data sets, consisting of complete, anatomically detailed, three-dimensional representations of the normal male and female human bodies.Tuna: Common name for various species of large, vigorous ocean fishes in the family Scombridae.