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Suspended Animation
Suspended animation is the slowing or stopping of biological function so that physiological capabilities are preserved. States of suspended animation are common in micro-organisms and some plant tissue, such as seeds. Many animals, including large ones, may undergo hibernation, and most plants have periods of dormancy. This article focuses primarily on the potential of large animals, especially humans, to undergo suspended animation. In animals, suspended animation may be either hypometabolic or ametabolic in nature. It may be induced by either endogenous, natural or artificial biological, chemical or physical means. In its natural form, it may be spontaneously reversible as in the case of species demonstrating hypometabolic states of hibernation. When applied with therapeutic intent, as in deep hypothermic circulatory arrest (DHCA), usually technologically mediated revival is required. Basic principles Suspended animation is understood as the pausing of life processes b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Death
A molecule is a group of two or more atoms that are held together by attractive forces known as chemical bonds; depending on context, the term may or may not include ions that satisfy this criterion. In quantum physics, organic chemistry, and biochemistry, the distinction from ions is dropped and ''molecule'' is often used when referring to polyatomic ions. A molecule may be homonuclear, that is, it consists of atoms of one chemical element, e.g. two atoms in the oxygen molecule (O2); or it may be heteronuclear, a chemical compound composed of more than one element, e.g. water (two hydrogen atoms and one oxygen atom; H2O). In the kinetic theory of gases, the term ''molecule'' is often used for any gaseous particle regardless of its composition. This relaxes the requirement that a molecule contains two or more atoms, since the noble gases are individual atoms. Atoms and complexes connected by non-covalent interactions, such as hydrogen bonds or ionic bonds, are typically not ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryonics
Cryonics (from ''kryos'', meaning "cold") is the low-temperature freezing (usually at ) and storage of human remains in the hope that resurrection may be possible in the future. Cryonics is regarded with skepticism by the mainstream scientific community. It is generally viewed as a pseudoscience, and its practice has been characterized as quackery. Cryonics procedures can begin only after the "patients" are clinically and legally dead. Procedures may begin within minutes of death, and use cryoprotectants to try to prevent ice formation during cryopreservation. It is not possible to reanimate a corpse that has undergone vitrification, as this damages the brain, including its neural circuits. The first corpse to be frozen was that of James Bedford, in 1967. As of 2014, remains from about 250 bodies had been cryopreserved in the United States, and 1,500 people had made arrangements for cryopreservation of theirs. Even if the resurrection promised by cryonics were pos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arrhenius Equation
In physical chemistry, the Arrhenius equation is a formula for the temperature dependence of reaction rates. The equation was proposed by Svante Arrhenius in 1889, based on the work of Dutch chemist Jacobus Henricus van 't Hoff who had noted in 1884 that the Van 't Hoff equation for the temperature dependence of equilibrium constants suggests such a formula for the rates of both forward and reverse reactions. This equation has a vast and important application in determining the rate of chemical reactions and for calculation of Activation energy, energy of activation. Arrhenius provided a physical justification and interpretation for the formula.Keith J. Laidler, Laidler, K. J. (1987) ''Chemical Kinetics'', Third Edition, Harper & Row, p. 42 Currently, it is best seen as an empirical relationship.Kenneth Connors, Chemical Kinetics, 1990, VCH Publishers It can be used to model the temperature variation of Mass diffusivity, diffusion coefficients, population of Vacancy defect, crystal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Torpor
Torpor is a state of decreased physiological activity in an animal, usually marked by a reduced body temperature and metabolic rate. Torpor enables animals to survive periods of reduced food availability. The term "torpor" can refer to the time a hibernator spends at low body temperature, lasting days to weeks, or it can refer to a period of low body temperature and metabolism lasting less than 24 hours. The word comes from the early 13th century, originating from the Latin, ''torpor'', to be numb or sluggish. Animals that undergo torpor include birds (hummingbirds, notably strisores) and some mammals, including many marsupial species, rodent species (such as mice), and bats. During the active part of their day, such animals maintain normal body temperature and activity levels, but their metabolic rate and body temperature drop during a portion of the day (usually night) to conserve energy. Some animals seasonally go into long periods of inactivity, with reduced body temperat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heart-lung Machine
Cardiopulmonary bypass (CPB) or heart-lung machine, also called the pump or CPB pump, is a machine that temporarily takes over the function of the heart and lungs during open-heart surgery by maintaining the circulation of blood and oxygen throughout the body. As such it is an extracorporeal device. CPB is operated by a perfusionist. The machine mechanically circulates and oxygenates blood throughout the patient's body while bypassing the heart and lungs allowing the surgeon to work in a bloodless surgical field. Uses CPB is commonly used in operations or surgical procedures involving the heart. The technique allows the surgical team to oxygenate and circulate the patient's blood, thus allowing the surgeon to operate safely on the heart. In many operations, such as coronary artery bypass grafting (CABG), the heart is arrested, due to the degree of the difficulty of operating on a beating heart. Operations requiring the opening of the chambers of the heart, for example mitra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Juan Luis Arsuaga
Juan Luis Arsuaga Ferreras (born 1954 in Madrid) is a Spanish paleoanthropologist and author known for his work in the Archaeological Site of Atapuerca, Atapuerca Archaeological Site. He obtained a master's degree and a doctorate in Biology, Biological Sciences at the Complutense University of Madrid, Universidad Complutense de Madrid, where he is professor in the Paleontology Department of thFaculty of Geological Sciences As a child he already showed a great interest in prehistory after reading ''The Quest for Fire'' and visiting a dig in nearby Bilbao. Arsuaga is a Visiting scholar, visiting professor of the Department of Anthropology at the University College London and since 1982 he has been a member of the Research Team investigating Pleistocene deposits in the Atapuerca Mountains (Province of Burgos, Spain). He has been a co-director since 1991 with José María Bermúdez de Castro and Eudald Carbonell, Eudald Carbonell Roura of the Atapuerca Team, which was awarded the P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erika Nordby
Erika Nordby (born February 2000), also known as Baby Erika, Miracle Baby and Canada's Miracle Child, is a Canadian originally from Edmonton, Alberta known for having been revived after spending two hours without a heartbeat due to hypothermia. Nordby, then a 13-month-old toddler, had left her heated house nearly naked, while the air temperature was . Freezing Erika and her mother, 26-year-old Leyla Nordby, were spending the night of 22/23 February 2001 at a friend's home in Edmonton. Leyla and an unnamed friend had been out earlier in the night, leaving a relative of the friend to babysit. When the two returned to the home, the babysitter left through the back door, which had a broken latch. In the early hours of the morning, 13-month-old Erika left the house alone wearing only a diaper. The temperature outside was approximately . As the girl customarily had a bottle around 2 am, her mother became concerned when she awoke at 3 am and Erika was not beside her in bed. Leyla found h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypothermia
Hypothermia is defined as a body core temperature below in humans. Symptoms depend on the temperature. In mild hypothermia, there is shivering and mental confusion. In moderate hypothermia, shivering stops and confusion increases. In severe hypothermia, there may be hallucinations and paradoxical undressing, in which a person removes their clothing, as well as an increased risk of the heart stopping. Hypothermia has two main types of causes. It classically occurs from exposure to cold weather and cold water immersion. It may also occur from any condition that decreases heat production or increases heat loss. Commonly, this includes alcohol intoxication but may also include low blood sugar, anorexia and advanced age. Body temperature is usually maintained near a constant level of through thermoregulation. Efforts to increase body temperature involve shivering, increased voluntary activity, and putting on warmer clothing. Hypothermia may be diagnosed based on either a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
