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.Cold Temperature: An absence of warmth or heat or a temperature notably below an accustomed norm.Hot Temperature: Presence of warmth or heat or a temperature notably higher than an accustomed norm.Skin Temperature: The TEMPERATURE at the outer surface of the body.Hypothermia: Lower than normal body temperature, especially in warm-blooded animals.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)Fever: An abnormal elevation of body temperature, usually as a result of a pathologic process.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.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)Shivering: Involuntary contraction or twitching of the muscles. It is a physiologic method of heat production in man and other mammals.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.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.Sciuridae: A family of the order Rodentia which contains 49 genera. Some of the more common genera are MARMOTA, which includes the marmot and woodchuck; Sciurus, the gray squirrel, S. carolinensis, and the fox squirrel, S. niger; Tamias, the eastern and western chipmunk; and Tamiasciurus, the red squirrel. The flying squirrels, except the scaly-tailed Anomaluridae, also belong to this family.Thermogenesis: The generation of heat in order to maintain body temperature. The uncoupled oxidation of fatty acids contained within brown adipose tissue and SHIVERING are examples of thermogenesis in MAMMALS.Sweating: The process of exocrine secretion of the SWEAT GLANDS, including the aqueous sweat from the ECCRINE GLANDS and the complex viscous fluids of the APOCRINE GLANDS.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.Humidity: A measure of the amount of WATER VAPOR in the air.Heat Stress Disorders: A group of conditions that develop due to overexposure or overexertion in excessive environmental heat.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.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.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Antipyretics: Drugs that are used to reduce body temperature in fever.Immersion: The placing of a body or a part thereof into a liquid.Pyrogens: Substances capable of increasing BODY TEMPERATURE and cause FEVER and may be used for FEVER THERAPY. They may be of microbial origin, often POLYSACCHARIDES, and may contaminate distilled water.Preoptic Area: Region of hypothalamus between the ANTERIOR COMMISSURE and OPTIC CHIASM.Motor Activity: The physical activity of a human or an animal as a behavioral phenomenon.Rectum: The distal segment of the LARGE INTESTINE, between the SIGMOID COLON and the ANAL CANAL.Thermosensing: The sensation of cold, heat, coolness, and warmth as detected by THERMORECEPTORS.Incubators, Infant: Electrically powered devices that are intended to assist in the maintenance of the thermal balance of infants, principally by controlling the air temperature and humidity in an enclosure. (from UMDNS, 1999)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.Energy Metabolism: The chemical reactions involved in the production and utilization of various forms of energy in cells.Hypothalamus: Ventral part of the DIENCEPHALON extending from the region of the OPTIC CHIASM to the caudal border of the MAMMILLARY BODIES and forming the inferior and lateral walls of the THIRD VENTRICLE.Heart Rate: The number of times the HEART VENTRICLES contract per unit of time, usually per minute.Basal Metabolism: Heat production, or its measurement, of an organism at the lowest level of cell chemistry in an inactive, awake, fasting state. It may be determined directly by means of a calorimeter or indirectly by calculating the heat production from an analysis of the end products of oxidation within the organism or from the amount of oxygen utilized.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.Behavior, Animal: The observable response an animal makes to any situation.Sleep: A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility.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.Hydrogen-Ion Concentration: The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Water: A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Oxygen Consumption: The rate at which oxygen is used by a tissue; microliters of oxygen STPD used per milligram of tissue per hour; the rate at which oxygen enters the blood from alveolar gas, equal in the steady state to the consumption of oxygen by tissue metabolism throughout the body. (Stedman, 25th ed, p346)Thermodynamics: A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)N-Methyl-3,4-methylenedioxyamphetamine: An N-substituted amphetamine analog. It is a widely abused drug classified as a hallucinogen and causes marked, long-lasting changes in brain serotonergic systems. It is commonly referred to as MDMA or ecstasy.Transition Temperature: The temperature at which a substance changes from one state or conformation of matter to another.Injections, Intraventricular: Injections into the cerebral ventricles.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.Eating: The consumption of edible substances.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)Cold Climate: A climate characterized by COLD TEMPERATURE for a majority of the time during the year.Adaptation, Physiological: The non-genetic biological changes of an organism in response to challenges in its ENVIRONMENT.Respiration: The act of breathing with the LUNGS, consisting of INHALATION, or the taking into the lungs of the ambient air, and of EXHALATION, or the expelling of the modified air which contains more CARBON DIOXIDE than the air taken in (Blakiston's Gould Medical Dictionary, 4th ed.). This does not include tissue respiration (= OXYGEN CONSUMPTION) or cell respiration (= CELL RESPIRATION).Clothing: Fabric or other material used to cover the body.Beluga Whale: The species Delphinapterus leucas, in the family Monodontidae, found primarily in the Arctic Ocean and adjoining seas. They are small WHALES lacking a dorsal fin.Rewarming: Application of heat to correct hypothermia, accidental or induced.Wakefulness: A state in which there is an enhanced potential for sensitivity and an efficient responsiveness to external stimuli.Climate: The longterm manifestations of WEATHER. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)LizardsCerebral Ventricles: Four CSF-filled (see CEREBROSPINAL FLUID) cavities within the cerebral hemispheres (LATERAL VENTRICLES), in the midline (THIRD VENTRICLE) and within the PONS and MEDULLA OBLONGATA (FOURTH VENTRICLE).Ear Canal: The narrow passage way that conducts the sound collected by the EAR AURICLE to the TYMPANIC MEMBRANE.Environment, Controlled: A state in which the environs of hospitals, laboratories, domestic and animal housing, work places, spacecraft, and other surroundings are under technological control with regard to air conditioning, heating, lighting, humidity, ventilation, and other ambient features. The concept includes control of atmospheric composition. (From Jane's Aerospace Dictionary, 3d ed)Adipose Tissue, Brown: A thermogenic form of adipose tissue composed of BROWN ADIPOCYTES. It is found in newborns of many species including humans, and in hibernating mammals. Brown fat is richly vascularized, innervated, and densely packed with MITOCHONDRIA which can generate heat directly from the stored lipids.Mytilus: A genus of marine mussels in the family MYTILIDAE, class BIVALVIA. The species MYTILUS EDULIS is the highly edible common mussel.Dimensional Measurement Accuracy: The closeness of a determined value of a physical dimension to the actual value.Kinetics: The rate dynamics in chemical or physical systems.Stress, Physiological: The unfavorable effect of environmental factors (stressors) on the physiological functions of an organism. Prolonged unresolved physiological stress can affect HOMEOSTASIS of the organism, and may lead to damaging or pathological conditions.Alligators and Crocodiles: Large, long-tailed reptiles, including caimans, of the order Loricata.Comb and Wattles: Fleshy and reddish outgrowth of skin tissue found on top of the head, attached to the sides of the head, and hanging from the mandible of birds such as turkeys and chickens.Carbon Dioxide: A colorless, odorless gas that can be formed by the body and is necessary for the respiration cycle of plants and animals.Air: The mixture of gases present in the earth's atmosphere consisting of oxygen, nitrogen, carbon dioxide, and small amounts of other gases.Cold-Shock Response: A constellation of responses that occur when an organism is exposed to excessive cold. In humans, a fall in skin temperature triggers gasping, hypertension, and hyperventilation.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.Water Loss, Insensible: Loss of water by diffusion through the skin and by evaporation from the respiratory tract.Calorimetry, Differential Scanning: Differential thermal analysis in which the sample compartment of the apparatus is a differential calorimeter, allowing an exact measure of the heat of transition independent of the specific heat, thermal conductivity, and other variables of the sample.Body Weight: The mass or quantity of heaviness of an individual. It is expressed by units of pounds or kilograms.Acclimatization: Adaptation to a new environment or to a change in the old.Environment: The external elements and conditions which surround, influence, and affect the life and development of an organism or population.Photoperiod: The time period of daily exposure that an organism receives from daylight or artificial light. It is believed that photoperiodic responses may affect the control of energy balance and thermoregulation.Analysis of Variance: A statistical technique that isolates and assesses the contributions of categorical independent variables to variation in the mean of a continuous dependent variable.Light: That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.Baths: The immersion or washing of the body or any of its parts in water or other medium for cleansing or medical treatment. It includes bathing for personal hygiene as well as for medical purposes with the addition of therapeutic agents, such as alkalines, antiseptics, oil, etc.Sleep, REM: A stage of sleep characterized by rapid movements of the eye and low voltage fast pattern EEG. It is usually associated with dreaming.Acetaminophen: Analgesic antipyretic derivative of acetanilide. It has weak anti-inflammatory properties and is used as a common analgesic, but may cause liver, blood cell, and kidney damage.Melatonin: A biogenic amine that is found in animals and plants. In mammals, melatonin is produced by the PINEAL GLAND. Its secretion increases in darkness and decreases during exposure to light. Melatonin is implicated in the regulation of SLEEP, mood, and REPRODUCTION. Melatonin is also an effective antioxidant.Rats, Sprague-Dawley: A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.Freezing: Liquids transforming into solids by the removal of heat.Tympanic Membrane: An oval semitransparent membrane separating the external EAR CANAL from the tympanic cavity (EAR, MIDDLE). It contains three layers: the skin of the external ear canal; the core of radially and circularly arranged collagen fibers; and the MUCOSA of the middle ear.Ear: The hearing and equilibrium system of the body. It consists of three parts: the EXTERNAL EAR, the MIDDLE EAR, and the INNER EAR. Sound waves are transmitted through this organ where vibration is transduced to nerve signals that pass through the ACOUSTIC NERVE to the CENTRAL NERVOUS SYSTEM. The inner ear also contains the vestibular organ that maintains equilibrium by transducing signals to the VESTIBULAR NERVE.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Brain: The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.Models, Biological: Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Whale, Killer: The species Orcinus orca, in the family Delphinidae, characterized by its black and white coloration, and huge triangular dorsal fin. It is the largest member of the DOLPHINS and derives its name from the fact that it is a fearsome predator.Heat-Shock Response: A constellation of responses that occur when an organism is exposed to excessive heat. Responses include synthesis of new proteins and regulation of others.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.Feeding Behavior: Behavioral responses or sequences associated with eating including modes of feeding, rhythmic patterns of eating, and time intervals.Species Specificity: The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.Dose-Response Relationship, Drug: The relationship between the dose of an administered drug and the response of the organism to the drug.Skin Physiological Phenomena: The functions of the skin in the human and animal body. It includes the pigmentation of the skin.Arousal: Cortical vigilance or readiness of tone, presumed to be in response to sensory stimulation via the reticular activating system.Escherichia coli: A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.Cattle: Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.Physical Exertion: Expenditure of energy during PHYSICAL ACTIVITY. Intensity of exertion may be measured by rate of OXYGEN CONSUMPTION; HEAT produced, or HEART RATE. Perceived exertion, a psychological measure of exertion, is included.Marsupialia: An infraclass of MAMMALS, also called Metatheria, where the young are born at an early stage of development and continue to develop in a pouch (marsupium). In contrast to Eutheria (placentals), marsupials have an incomplete PLACENTA.Injections: Introduction of substances into the body using a needle and syringe.Rabbits: The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.Protective Clothing: Clothing designed to protect the individual against possible exposure to known hazards.Hypothalamus, Anterior: The front portion of the HYPOTHALAMUS separated into the preoptic region and the supraoptic region. The preoptic region is made up of the periventricular GRAY MATTER of the rostral portion of the THIRD VENTRICLE and contains the preoptic ventricular nucleus and the medial preoptic nucleus. The supraoptic region contains the PARAVENTRICULAR HYPOTHALAMIC NUCLEUS, the SUPRAOPTIC NUCLEUS, the ANTERIOR HYPOTHALAMIC NUCLEUS, and the SUPRACHIASMATIC NUCLEUS.Rats, Wistar: A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.Analgesics, Non-Narcotic: A subclass of analgesic agents that typically do not bind to OPIOID RECEPTORS and are not addictive. Many non-narcotic analgesics are offered as NONPRESCRIPTION DRUGS.Forehead: The part of the face above the eyes.Serotonin: A biochemical messenger and regulator, synthesized from the essential amino acid L-TRYPTOPHAN. In humans it is found primarily in the central nervous system, gastrointestinal tract, and blood platelets. Serotonin mediates several important physiological functions including neurotransmission, gastrointestinal motility, hemostasis, and cardiovascular integrity. Multiple receptor families (RECEPTORS, SEROTONIN) explain the broad physiological actions and distribution of this biochemical mediator.Eccrine Glands: Simple sweat glands that secrete sweat directly onto the SKIN.TailMice, Inbred C57BLSwine: Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).Antelopes: Any of various ruminant mammals of the order Bovidae. They include numerous species in Africa and the American pronghorn.Sodium Chloride: A ubiquitous sodium salt that is commonly used to season food.Acrylamides: Colorless, odorless crystals that are used extensively in research laboratories for the preparation of polyacrylamide gels for electrophoresis and in organic synthesis, and polymerization. Some of its polymers are used in sewage and wastewater treatment, permanent press fabrics, and as soil conditioning agents.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.Ecosystem: A functional system which includes the organisms of a natural community together with their environment. (McGraw Hill Dictionary of Scientific and Technical Terms, 4th ed)Skin: The outer covering of the body that protects it from the environment. It is composed of the DERMIS and the EPIDERMIS.Calorimetry: The measurement of the quantity of heat involved in various processes, such as chemical reactions, changes of state, and formations of solutions, or in the determination of the heat capacities of substances. The fundamental unit of measurement is the joule or the calorie (4.184 joules). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Enzyme Stability: The extent to which an enzyme retains its structural conformation or its activity when subjected to storage, isolation, and purification or various other physical or chemical manipulations, including proteolytic enzymes and heat.Swimming: An activity in which the body is propelled through water by specific movement of the arms and/or the legs. Swimming as propulsion through water by the movement of limbs, tail, or fins of animals is often studied as a form of PHYSICAL EXERTION or endurance.Animals, Newborn: Refers to animals in the period of time just after birth.Ovulation Detection: Method to determine the occurrence of OVULATION by direct or indirect means. Indirect methods examine the effects of PROGESTERONE on cervical mucus (CERVIX MUCUS), or basal body temperature. Direct ovulation detection, generally used in fertility treatment, involves analyses of circulating hormones in blood and ULTRASONOGRAPHY.Apnea: A transient absence of spontaneous respiration.Scrotum: A cutaneous pouch of skin containing the testicles and spermatic cords.Respiratory Rate: The number of times an organism breathes with the lungs (RESPIRATION) per unit time, usually per minute.Hydrocortisone: The main glucocorticoid secreted by the ADRENAL CORTEX. Its synthetic counterpart is used, either as an injection or topically, in the treatment of inflammation, allergy, collagen diseases, asthma, adrenocortical deficiency, shock, and some neoplastic conditions.Echidna: An oviparous burrowing mammal of the order Monotremata native to Australia, Tasmania, and New Guinea. It has hair mingled with spines on the upper part of the body and is adapted for feeding on ants.TRPV Cation Channels: A subgroup of TRP cation channels named after vanilloid receptor. They are very sensitive to TEMPERATURE and hot spicy food and CAPSAICIN. They have the TRP domain and ANKYRIN repeats. Selectivity for CALCIUM over SODIUM ranges from 3 to 100 fold.Hedgehogs: The family Erinaceidae, in the order INSECTIVORA. Most are true hedgehogs possessing a coat of spines and a very short tail. Those members of the family found in Southeast Asia (moonrats or gymnures) have normal body hair and a long tail.Remote Sensing Technology: Observation and acquisition of physical data from a distance by viewing and making measurements from a distance or receiving transmitted data from observations made at distant location.Mytilidae: A family of marine MUSSELS in the class BIVALVIA.Activity Cycles: Bouts of physical irritability or movement alternating with periods of quiescence. It includes biochemical activity and hormonal activity which may be cellular. These cycles are shorter than 24 hours and include sleep-wakefulness cycles and the periodic activation of the digestive system.Ergotamines: A series of structurally-related alkaloids containing the ergotaman backbone structure.Body Size: The physical measurements of a body.Blood Pressure: PRESSURE of the BLOOD on the ARTERIES and other BLOOD VESSELS.Norepinephrine: Precursor of epinephrine that is secreted by the adrenal medulla and is a widespread central and autonomic neurotransmitter. Norepinephrine is the principal transmitter of most postganglionic sympathetic fibers and of the diffuse projection system in the brain arising from the locus ceruleus. It is also found in plants and is used pharmacologically as a sympathomimetic.Dilatation: The act of dilating.Sleep Stages: Periods of sleep manifested by changes in EEG activity and certain behavioral correlates; includes Stage 1: sleep onset, drowsy sleep; Stage 2: light sleep; Stages 3 and 4: delta sleep, light sleep, deep sleep, telencephalic sleep.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.Iguanas: Large herbivorous tropical American lizards.Receptor, Galanin, Type 3: A galanin receptor subtype with high affinity for GALANIN-LIKE PEPTIDE and low affinity for full length GALANIN and galanin peptide fragments.Seawater: The salinated water of OCEANS AND SEAS that provides habitat for marine organisms.Anesthesia: A state characterized by loss of feeling or sensation. This depression of nerve function is usually the result of pharmacologic action and is induced to allow performance of surgery or other painful procedures.Mouth: The oval-shaped oral cavity located at the apex of the digestive tract and consisting of two parts: the vestibule and the oral cavity proper.Hallucinogens: Drugs capable of inducing illusions, hallucinations, delusions, paranoid ideations, and other alterations of mood and thinking. Despite the name, the feature that distinguishes these agents from other classes of drugs is their capacity to induce states of altered perception, thought, and feeling that are not experienced otherwise.Oxygen: An element with atomic symbol O, atomic number 8, and atomic weight [15.99903; 15.99977]. It is the most abundant element on earth and essential for respiration.Galanin-Like Peptide: A neuropeptide that is highly homologous to GALANIN. It is produced by proteolytic processing of a larger protein that is unrelated to prepro-galanin and preferentially binds to GALANIN-2 RECEPTOR.Dehydration: The condition that results from excessive loss of water from a living organism.Protein Denaturation: Disruption of the non-covalent bonds and/or disulfide bonds responsible for maintaining the three-dimensional shape and activity of the native protein.Housing, AnimalMonitoring, Physiologic: The continuous measurement of physiological processes, blood pressure, heart rate, renal output, reflexes, respiration, etc., in a patient or experimental animal; includes pharmacologic monitoring, the measurement of administered drugs or their metabolites in the blood, tissues, or urine.Disease Models, Animal: Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.Pedophilia: A sexual disorder occurring in a person 16 years or older and that is recurrent with intense sexually arousing fantasies, sexual urges, or behaviors involving sexual activity with a prepubescent child (generally age 13 or younger). (from APA, DSM-IV, 1994).Phase Transition: A change of a substance from one form or state to another.Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Autonomic Agents: Agents affecting the function of, or mimicking the actions of, the autonomic nervous system and thereby having an effect on such processes as respiration, circulation, digestion, body temperature regulation, certain endocrine gland secretions, etc.Tropical Climate: A climate which is typical of equatorial and tropical regions, i.e., one with continually high temperatures with considerable precipitation, at least during part of the year. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Heat Exhaustion: A clinical syndrome caused by heat stress, such as over-exertion in a hot environment or excessive exposure to sun. It is characterized by SWEATING, water (volume) depletion, salt depletion, cool clammy skin, NAUSEA, and HEADACHE.Weather: The state of the ATMOSPHERE over minutes to months.Drinking: The consumption of liquids.Clinical Nursing Research: Research carried out by nurses in the clinical setting and designed to provide information that will help improve patient care. Other professional staff may also participate in the research.Desert Climate: A type of climate characterized by insufficient moisture to support appreciable plant life. It is a climate of extreme aridity, usually of extreme heat, and of negligible rainfall. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Urethane: Antineoplastic agent that is also used as a veterinary anesthetic. It has also been used as an intermediate in organic synthesis. Urethane is suspected to be a carcinogen.Methamphetamine: A central nervous system stimulant and sympathomimetic with actions and uses similar to DEXTROAMPHETAMINE. The smokable form is a drug of abuse and is referred to as crank, crystal, crystal meth, ice, and speed.Ibuprofen: A nonsteroidal anti-inflammatory agent with analgesic properties used in the therapy of rheumatism and arthritis.Dysmenorrhea: Painful menstruation.Serotonin Agents: Drugs used for their effects on serotonergic systems. Among these are drugs that affect serotonin receptors, the life cycle of serotonin, and the survival of serotonergic neurons.Chlormethiazole: A sedative and anticonvulsant often used in the treatment of alcohol withdrawal. Chlormethiazole has also been proposed as a neuroprotective agent. The mechanism of its therapeutic activity is not entirely clear, but it does potentiate GAMMA-AMINOBUTYRIC ACID receptors response and it may also affect glycine receptors.Laryngeal Nerves: Branches of the VAGUS NERVE. The superior laryngeal nerves originate near the nodose ganglion and separate into external branches, which supply motor fibers to the cricothyroid muscles, and internal branches, which carry sensory fibers. The RECURRENT LARYNGEAL NERVE originates more caudally and carries efferents to all muscles of the larynx except the cricothyroid. The laryngeal nerves and their various branches also carry sensory and autonomic fibers to the laryngeal, pharyngeal, tracheal, and cardiac regions.Refrigeration: The mechanical process of cooling.Ice: The solid substance formed by the FREEZING of water.Phenotype: The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.Suprachiasmatic Nucleus: An ovoid densely packed collection of small cells of the anterior hypothalamus lying close to the midline in a shallow impression of the OPTIC CHIASM.Chills: The sudden sensation of being cold. It may be accompanied by SHIVERING.Drug Stability: The chemical and physical integrity of a pharmaceutical product.Heat-Shock Proteins: Proteins which are synthesized in eukaryotic organisms and bacteria in response to hyperthermia and other environmental stresses. They increase thermal tolerance and perform functions essential to cell survival under these conditions.Cheirogaleidae: A family of the order PRIMATES, suborder Strepsirhini (PROSIMII), containing five genera. All inhabitants of Madagascar, the genera are: Allocebus, Cheirogaleus (dwarf lemurs), Microcebus (mouse lemurs), Mirza, and Phaner.Regional Blood Flow: The flow of BLOOD through or around an organ or region of the body.Myoxidae: A family of nocturnal rodents, similar in appearance to SQUIRRELS, but smaller. There are 28 species, half of which are found in Africa.Viscosity: The resistance that a gaseous or liquid system offers to flow when it is subjected to shear stress. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Convection: Transmission of energy or mass by a medium involving movement of the medium itself. The circulatory movement that occurs in a fluid at a nonuniform temperature owing to the variation of its density and the action of gravity. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed; Webster, 10th ed)Anterior Hypothalamic Nucleus: Loose heterogeneous collection of cells in the anterior hypothalamus, continuous rostrally with the medial and lateral PREOPTIC AREAS and caudally with the TUBER CINEREUM.Endotoxins: Toxins closely associated with the living cytoplasm or cell wall of certain microorganisms, which do not readily diffuse into the culture medium, but are released upon lysis of the cells.Magnetic Resonance Spectroscopy: Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).Locomotion: Movement or the ability to move from one place or another. It can refer to humans, vertebrate or invertebrate animals, and microorganisms.Gastropoda: A class in the phylum MOLLUSCA comprised of SNAILS and slugs. The former have coiled external shells and the latter usually lack shells.Rain: Water particles that fall from the ATMOSPHERE.ShrewsDarkness: The absence of light.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Antarctic Regions: The continent lying around the South Pole and the southern waters of the Atlantic, Pacific, and Indian Oceans. It includes the Falkland Islands Dependencies. (From Webster's New Geographical Dictionary, 1988, p55)Reptiles: Cold-blooded, air-breathing VERTEBRATES belonging to the class Reptilia, usually covered with external scales or bony plates.Jet Lag Syndrome: A chronobiologic disorder resulting from rapid travel across a number of time zones, characterized by insomnia or hypersomnolence, fatigue, behavioral symptoms, headaches, and gastrointestinal disturbances. (From Cooper, Sleep, 1994, pp593-8)Anesthesia, General: Procedure in which patients are induced into an unconscious state through use of various medications so that they do not feel pain during surgery.