IatrogenesisIatrogenesis is the causation of a disease, a harmful complication, or other ill effect by any medical activity, including diagnosis, intervention, error, or negligence. First used in this sense in 1924, the term was introduced to sociology in 1976 by Ivan Illich, alleging that industrialized societies impair quality of life by overmedicalizing life. Iatrogenesis may thus include mental suffering via medical beliefs or a practitioner's statements.
Evolution of ageingEnquiry into the evolution of ageing, or aging, aims to explain why a detrimental process such as ageing would evolve, and why there is so much variability in the lifespans of organisms. The classical theories of evolution (mutation accumulation, antagonistic pleiotropy, and disposable soma) suggest that environmental factors, such as predation, accidents, disease, and/or starvation, ensure that most organisms living in natural settings will not live until old age, and so there will be very little pressure to conserve genetic changes that increase longevity.
BiogerontologyBiogerontology is the sub-field of gerontology concerned with the biological aging process, its evolutionary origins, and potential means to intervene in the process. The term "biogerontology" was coined by S. Rattan, and came in regular use with the start of the journal BIOGERONTOLOGY in 2000. It involves interdisciplinary research on the causes, effects, and mechanisms of biological aging. Biogerontologist Leonard Hayflick has said that the natural average lifespan for a human is around 92 years and, if humans do not invent new approaches to treat aging, they will be stuck with this lifespan.
Biological immortalityBiological immortality (sometimes referred to as bio-indefinite mortality) is a state in which the rate of mortality from senescence is stable or decreasing, thus decoupling it from chronological age. Various unicellular and multicellular species, including some vertebrates, achieve this state either throughout their existence or after living long enough. A biologically immortal living being can still die from means other than senescence, such as through injury, poison, disease, predation, lack of available resources, or changes to environment.
Sky burialSky burial (, "bird-scattered") is a funeral practice in which a human corpse is placed on a mountaintop to decompose while exposed to the elements or to be eaten by scavenging animals, especially carrion birds. It is a specific type of the general practice of excarnation. It is practiced in the Chinese provinces and autonomous regions of Tibet, Qinghai, Sichuan, and Inner Mongolia, as well as in Mongolia, Bhutan, and parts of India such as Sikkim and Zanskar.
Suspended animationSuspended animation is the temporary (short- or long-term) slowing or stopping of biological function so that physiological capabilities are preserved. It 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.
CadaverA cadaver or corpse is a dead human body. Cadavers are used by medical students, physicians and other scientists to study anatomy, identify disease sites, determine causes of death, and provide tissue to repair a defect in a living human being. Students in medical school study and dissect cadavers as a part of their education. Others who study cadavers include archaeologists and arts students. In addition, a cadaver may be used in the development and evaluation of surgical instruments.
Rigor mortisRigor mortis (Latin: rigor "stiffness", and mortis "of death"), or postmortem rigidity, is the fourth stage of death. It is one of the recognizable signs of death, characterized by stiffening of the limbs of the corpse caused by chemical changes in the muscles postmortem (mainly calcium). In humans, rigor mortis can occur as soon as four hours after death. Contrary to folklore and common belief, rigor mortis is not permanent and begins to pass within hours of onset. Typically, it lasts no longer than eight hours at "room temperature".
Livor mortisLivor mortis (Latin: līvor – "bluish color, bruise", mortis – "of death"), postmortem lividity (Latin: postmortem – "after death", lividity – "black and blue"), hypostasis (Greek: ὑπό, hypo, meaning "under, beneath"; στάσις, stasis, meaning "a standing") or suggillation, is the second stage of death and one of the signs of death. It is a settling of the blood in the lower, or dependent, portion of the body postmortem, causing a purplish red discoloration of the skin.
DisembowelmentDisembowelment, evisceration or gutting is the removal of some or all of the organs of the gastrointestinal tract (bowels or viscera), usually through a incision made across the abdominal area. Evisceration is a routine operation during the animal slaughter. In the ancient Rome, disembowelment of animals was practised for divination and was known as haruspicy. Disembowelment of humans may result from an accident but has also been used as a method of torture, execution or suicide.