Tribonucleation

	Tribonucleation Tribonucleation is a mechanism that creates small gas bubbles by the action of making and breaking contact between solid surfaces immersed in a liquid containing dissolved gas. These small bubbles may then act as nuclei for the growth of bubbles when the pressure is reduced. As the formation of the nuclei occurs quite easily, the effect may occur in a human body engaged in light exercise, yet produce no symptoms. However tribonucleation may be a source of growing bubbles affecting scuba divers when ascending to the surface and is a potential cause of decompression sickness. The process has also been described as the basis for the cracking sound produced by the manipulation of human synovial joints. References {{reflist , refs= {{cite journal , last1= Hugon , first1= J. , last2= Barthelemy , first2= L. , last3= Rostain , first3= J.C. , last4= Gardette , first4= B. , title=The pathway to drive decompression microbubbles from the tissues to the blood and the lymphatic system ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Decompression Sickness Decompression sickness (DCS; also called divers' disease, the bends, aerobullosis, and caisson disease) is a medical condition caused by dissolved gases emerging from Solution (chemistry), solution as bubbles inside the body tissues during Decompression (diving), decompression. DCS most commonly occurs during or soon after a decompression ascent from underwater diving, but can also result from other causes of depressurisation, such as emerging from a Caisson (engineering), caisson, decompression from Saturation diving, saturation, flying in an Cabin pressurization, unpressurised aircraft at high altitude, and extravehicular activity from spacecraft. DCS and Air embolism, arterial gas embolism are collectively referred to as decompression illness. Since bubbles can form in or migrate to any part of the body, DCS can produce many symptoms, and its effects may vary from joint pain and rashes to paralysis and death. DCS often causes air bubbles to settle in major joints like knee ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Cracking Joints Joint cracking is the manipulation of joints to produce a sound and related "popping" sensation. It is sometimes performed by physical therapists, chiropractors, and osteopaths pursuing a variety of outcomes. The cracking mechanism and the resulting sound is caused by dissolved gas (nitrogen gas) cavitation bubbles suddenly collapsing inside the joints. This happens when the joint cavity is stretched beyond its normal size. The pressure inside the joint cavity drops and the dissolved gas suddenly comes out of solution and takes gaseous form which makes a distinct popping noise. To be able to crack the same knuckle again requires waiting about 20 minutes before the bubbles dissolve back into the synovial fluid and will be able to form again. It is possible for voluntary joint cracking by an individual to be considered as part of the obsessive–compulsive disorders spectrum. Causes For many decades, the physical mechanism that causes the cracking sound as a result of bending ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Nucleation In thermodynamics, nucleation is the first step in the formation of either a new Phase (matter), thermodynamic phase or Crystal structure, structure via self-assembly or self-organization within a substance or mixture. Nucleation is typically defined to be the process that determines how long an observer has to wait before the new phase or self-organized structure appears. For example, if a volume of water is cooled (at atmospheric pressure) significantly below 0°C, it will tend to Freezing, freeze into ice, but volumes of water cooled only a few degrees below 0°C often stay completely free of ice for long periods (supercooling). At these conditions, nucleation of ice is either slow or does not occur at all. However, at lower temperatures nucleation is fast, and ice crystals appear after little or no delay. Nucleation is a common mechanism which generates first-order phase transitions, and it is the start of the process of forming a new thermodynamic phase. In contrast, new phas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Scuba Diver Scuba, originally SCUBA, often expanded to scuba set, is any self contained underwater breathing apparatus, a source of breathing gas used for underwater diving which is carried by the diver. Scuba may also refer to: * Scuba diving Scuba diving is a Diving mode, mode of underwater diving whereby divers use Scuba set, breathing equipment that is completely independent of a surface breathing gas supply, and therefore has a limited but variable endurance. The word ''scub ..., swimming underwater while breathing from a gas supply carried by the diver, * Scuba, an in-memory database developed by Facebook * Submillimetre Common-User Bolometer Array, either of two instruments used on the James Clerk Maxwell Telescope * Scuba (musician) * ''Scuba'' (album), 1984 P-Model album See also * Scooba (other) {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Undersea And Hyperbaric Medical Society The Undersea and Hyperbaric Medical Society (UHMS) is an organization based in the US which supports research on matters of hyperbaric medicine and physiology, and provides a certificate of added qualification for physicians with an unrestricted license to practice medicine and for limited licensed practitioners, at the completion of the Program for Advanced Training in Hyperbaric Medicine. They support an extensive library and are a primary source of information for diving and hyperbaric medicine physiology worldwide. History The Undersea Medical Society (UMS) grew from the close associations of a small group of scientists. These men realized after a series of ''International Symposia on Underwater Physiology'', initiated by the University of Pennsylvania and the Office of Naval Research that there was a need to stimulate in the field of undersea medicine. This group consisted of diving and aerospace Dr's Edward L. Beckman, Jack L. Kinsey, Christian J. Lambertsen, Walter F. Ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Mechanisms (engineering) Mechanism may refer to: Mechanism (economics), a set of Game form, rules for a game designed to achieve Social choice function, a certain outcome Mechanism design, the study of such mechanisms Mechanism (engineering), rigid bodies connected by joints in order to accomplish a desired force and/or motion transmission Mechanism (biology), explaining how a feature is created Mechanism (philosophy), a theory that all natural phenomena can be explained by physical causes Mechanism (sociology), a theory that all social phenomena can be explained by the existence of a deterministic mechanism Arts, films, and music "The Mechanism", song by Disclosure * "Mechanism", song by Front Line Assembly from ''WarMech'' * The Mechanism (TV series), ''The Mechanism'' (TV series), a Netflix TV series See also Machine Machine (mechanical) Linkage (mechanical) Mechanism of action, the means by which a drug exerts its biological effects Defence mechanism, unconscious mechanisms aimed a ... [...More Info...] [...Related Items...] OR:* [Wikipedia] [Google] [Baidu]
picture info	Underwater Diving Physiology Human physiology of underwater diving is the physiological influences of the underwater environment on the human diver, and adaptations to operating underwater, both during breath-hold dives and while breathing at ambient pressure from a suitable breathing gas supply. It, therefore, includes the range of physiological effects generally limited to human ambient pressure divers either freediving or using underwater breathing apparatus. Several factors influence the diver, including immersion, exposure to the water, the limitations of breath-hold endurance, variations in ambient pressure, the effects of breathing gases at raised ambient pressure, effects caused by the use of breathing apparatus, and sensory impairment. All of these may affect diver performance and safety. Immersion affects fluid balance, circulation and work of breathing. Exposure to cold water can result in the harmful cold shock response, the helpful diving reflex and excessive loss of body heat. Breath-hold dur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]