Cold Shock Response - Wikipedia

Physiological response to sudden exposure to cold

Cold shock response is a series of neurogenic cardio-respiratory responses caused by sudden immersion in cold water.

In cold water immersions, such as by falling through thin ice, cold shock response is perhaps the most common cause of death.[1] Also, the abrupt contact with very cold water may cause involuntary inhalation, which, if underwater, can result in fatal drowning.

Death which occurs in such scenarios is complex to investigate and there are several possible causes and phenomena that can take part. The cold water can cause heart attack due to severe vasoconstriction,[2] where the heart has to work harder to pump the same volume of blood throughout the arteries. For people with pre-existing cardiovascular disease, the additional workload can result in myocardial infarction and/or acute heart failure, which ultimately may lead to a cardiac arrest. A vagal response to an extreme stimulus as this one, may, in very rare cases, render per se a cardiac arrest. Hypothermia and extreme stress can both precipitate fatal tachyarrhythmias. A more modern view suggests that an autonomic conflict — sympathetic (due to stress) and parasympathetic (due to the diving reflex) coactivation — may be responsible for some cold water immersion deaths. Gasp reflex and uncontrollable tachypnea can severely increase the risk of water inhalation and drowning.[3]

Some people are much better prepared to survive sudden exposure to very cold water due to body and mental characteristics and due to conditioning.[1] In fact, cold water swimming (also known as ice swimming or winter swimming) is a sport and an activity that reportedly can lead to several health benefits when done regularly.[4]

Physiological response

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Cold water immersion syndrome — four-stage model

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The physiological response to a sudden immersion in cold water may be divided in three or four discrete stages, with different risks and physiological changes, all being part of an entity labelled as Cold Water Immersion Syndrome. Although this process is a continuum, the 4 phases were initially described in the 1980s as follows:[3][4]

Phase	Time	Physiological Changes
Initial (cold shock)	First 2 – 3 minutes	Cooling of the skin, hyperventilation, tachycardia, gasp reflex
Short-term	After 3 minutes	Superficial neuromuscular cooling
Long-term	After 30 min	Hypothermia, later collapse
Circum-rescue collapse (afterdrop)	Immediately before, during or after rescue	Cardiac arrhythmia, hemostasis, unconsciousness

The first stage of cold water immersion syndrome, the cold shock response, includes a group of reflexes lasting under 5 min in laboratory volunteers and initiated by thermoreceptors sensing rapid skin cooling. Water has a thermal conductivity 25 times and a volume-specific heat capacity over 3000 times that of air; subsequently, surface cooling is precipitous. The primary components of the cold shock reflex include gasping, tachypnea, reduced breath-holding time, and peripheral vasoconstriction, the latter effect highlighting the presumed physiologic principle (i.e., warmth preservation via central blood shunting). The magnitude of the cold shock response parallels the cutaneous cooling rate, and its termination is likely due to reflex baroreceptor responses or thermoreceptor habituation.

Diving reflex

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The diving reflex is a set of physiological responses that occur in response to cold water immersion, particularly when the face or body is exposed to cold water. It is an evolutionary adaptation that helps mammals, including humans, manage the challenges of being submerged in cold water. The diving reflex is more pronounced in aquatic mammals and is thought to have originated as a way to conserve oxygen and enhance the ability to stay underwater for longer periods.

Key components of the diving reflex include:

1. Bradycardia: The heart rate decreases significantly when the face is exposed to cold water. This helps to conserve oxygen by slowing down the heartbeat. The degree of bradycardia can vary among individuals, but it is a common and well-documented response.
2. Peripheral Vasoconstriction: Blood vessels in the extremities constrict, reducing blood flow to the limbs. This shunting of blood helps to redirect it to essential organs, such as the heart and brain, preserving oxygen for vital functions.
3. Apnea: The diving reflex triggers an involuntary breath-holding response (apnea). This allows individuals to hold their breath for longer periods, enhancing their ability to stay submerged without the immediate need to breathe.
4. Blood Redistribution: The body redistributes blood flow, prioritizing essential organs and minimizing blood flow to non-essential areas, such as the skin and muscles. This redistribution helps to conserve heat and oxygen.

While the diving reflex is more pronounced in some mammals, its presence in humans is well-documented, particularly in cold water situations. The reflex is more prominent in infants and young children but can be observed in individuals of all ages.[3]

Cardiac arrhythmias and autonomic conflict

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Early models of cold water immersion syndrome focused primarily on sympathetic responses, however recent research suggests sympathetic and parasympathetic coactivation (leading to a conflict of the autonomic system response) may be responsible for some cold water immersion deaths. Although reciprocal activation between sympathetic (cold shock) and parasympathetic (diving response) systems is commonly adaptive (follow one another), simultaneous activation appears to be associated with arrythmya. Cold water induced rhythm disturbances are common, albeit frequently asymptomatic. In most humans, head-out cold-water immersion results in sympathetically driven tachycardia with variable disturbances. These cold water immersion induced arrhythmias appear to be accentuated by parasympathetic stimulation resulting from facial submersion or breath holding. Even vagally dominant diving bradycardia caused by isolated cold water facial immersion frequently is interrupted by supraventricular arrhythmias or premature beats. In theory, atrioventricular blockade or sinus arrest due to profound parasympathetic dominance might result in syncope or sudden cardiac death, but these rhythms tend to be rapidly reversed by lung stretch receptor activation associated with breathing. As such, a vagally produced arrest scenario is likelier during entrapment submersion than in flush drowning.[3][4]

Conditioning against cold shock

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It is possible to undergo physiological conditioning to reduce the cold shock response, and some people are naturally better suited to swimming in very cold water. Beneficial adaptations include the following:

1. having an insulating layer of body fat covering the limbs and torso;[1]
2. ability to experience immersion without involuntary physical shock or mental panic;[1]
3. ability to resist shivering;[1]
4. ability to raise metabolism (and, in some cases, increase blood temperature slightly above the normal level);[citation needed]
5. a generalized delaying of metabolic shutdown (including slipping into unconsciousness) as central and peripheral body temperatures fall.[citation needed]

Benefits and Risks of cold water immersion

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Cold water immersion tactics are often employed by athletes to speed up muscle recovery and reduce inflammation and soreness after intense exercise or after trauma.[5]

There are several reported benefits from regular ice swimming, namely:[4]

• Cardiovascular system: Lowering blood pressure
• Endocrine system: Decrease in triglycerides, Increase in insulin sensitivity, Decrease in norepinephrine, Increase in cortisol
• Psychiatric: Antidepressant effect
• Immune system: Increase in leucocytes, Increase in monocytes, Fewer infections

Cold water swimming still poses a significant health risk for inexperienced and untrained swimmers. It is recommended that in order to fully benefit from the metabolic and thermogenic effects of cold water swimming, a grade and progressive acclimatization program is required and preferably done under supervisor.

Cold shock response in other organisms

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Cold shock in mammals

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Cold shock has been described in several species and at least part of the physiology is similar, as described above in the Diving Reflex.

Cold shock in bacteria

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A cold shock is when bacteria undergo a significant reduction in temperature, likely due to their environment dropping in temperature. To constitute as a cold shock the temperature reduction needs to be both significant, for example dropping from 37 °C to 20 °C, and it needs to happen over a short period of time, traditionally in under 24 hours.[6] Both prokaryotic and eukaryotic cells are capable of undergoing a cold shock response.[7] The effects of a cold shock in bacteria include:[8]

• Decreased cell membrane fluidity
• Decreased enzyme activity
• Decreased efficiency of transcription and translation
• Decreased efficiency of protein folding
• Decreased ribosome function

The bacteria uses the cytoplasmic membrane, RNA/DNA, and ribosomes as cold sensors in the cell, placing them in charge of monitoring the cell's temperature.[7] Once these sensors send the signal that a cold shock is occurring, the bacteria will pause the majority of protein synthesis in order to redirect its focus to producing what are called cold shock proteins (Csp).[9] The volume of the cold shock proteins produced will depend on the severity of the temperature decrease.[10] The function of these cold shock proteins is to assist the cell in adapting to the sudden temperature change, allowing it to maintain as close to a normal level of function as possible.[7]

One way cold shock proteins are thought to function is by acting as nucleic acid chaperones. These cold shock proteins will block the formation of secondary structures in the mRNA during the cold shock, leaving the bacteria with only single strand RNA.[8] Single strand is the most efficient form of RNA for the facilitation of transcription and translation. This will help to counteract the decreased efficiency of transcription and translation brought about by the cold shock.[10] Cold shock proteins also affect the formation of hairpin structures in the RNA, blocking them from being formed. The function of these hairpin structures is to slow down or decrease the transcription of RNA. So by removing them, this will also help to increase the efficiency of transcription and translation.[10]

Once the initial shock of the temperature decrease has been dealt with, the production of cold shock proteins is slowly tapered off.[8] Instead, other proteins are synthesized in their place as the cell continues to grow at this new lower temperature. However, the rate of growth seen by these bacterial cells at colder temperatures is often lower than the rates of growth they exhibit at warmer temperatures.[6]

Transcriptional response of Escherichia coli to cold shock

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Cold shocks cause the repression of several hundreds of genes in the bacterium E. coli. Many of these genes are repressed quickly after the decrease in temperature, while others are only affected several hours after this event.[11] The repression mechanism is described in.[12] Shortly, during cold-shocks, cellular energy levels decrease. This hampers the efficiency by which DNA gyrases remove positive supercoils produced by transcription events, whose accumulation eventually blocks future transcription events.

Many of the genes repressed during cold shock are involved in cell metabolism. By knowing the mechanism by which these genes respond, one can potentially tune it, in genetically modified bacteria, to modify at which temperature is the response to cold shock activated. This modification could reduce the energy costs of bioreactors.[12]

See also

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• Diving reflex – The physiological responses to immersion of air-breathing vertebrates
• Hypothermia – Human body core temperature below 35 °C (95 °F)
• Cold water immersion – Respiratory impairment caused by submersion in liquid

References

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1. ^ a b c d e "Exercise in the Cold: Part II - A physiological trip through cold water exposure". The science of sport. www.sportsscientists.com. 29 January 2008. Retrieved 2010-04-23.
2. ^ Staff. "4 Phases of Cold Water Immersion". Beyond Cold Water Bootcamp. Canadian Safe Boating Council. Archived from the original on 3 December 2013. Retrieved 8 November 2013.
3. ^ a b c d Farstad, David J.; Dunn, Julie A. (September 2019). "Cold Water Immersion Syndrome and Whitewater Recreation Fatalities". Wilderness & Environmental Medicine. 30 (3): 321–327. doi:10.1016/j.wem.2019.03.005. ISSN 1545-1534. PMID 31178366. S2CID 182948780.
4. ^ a b c d Knechtle, Beat; Waśkiewicz, Zbigniew; Sousa, Caio Victor; Hill, Lee; Nikolaidis, Pantelis T. (December 2020). "Cold Water Swimming—Benefits and Risks: A Narrative Review". International Journal of Environmental Research and Public Health. 17 (23): 8984. doi:10.3390/ijerph17238984. ISSN 1661-7827. PMC 7730683. PMID 33276648.
5. ^ Tipton, M. J.; Collier, N.; Massey, H.; Corbett, J.; Harper, M. (2017-11-01). "Cold water immersion: kill or cure?: Cold water immersion: kill or cure?". Experimental Physiology. 102 (11): 1335–1355. doi:10.1113/EP086283. PMID 28833689.
6. ^ a b Shires, K.; Steyn, L. (2001). "The cold-shock stress response in Mycobacterium smegmatis induces the expression of a histone-like protein". Molecular Microbiology. 39 (4): 994–1009. doi:10.1046/j.1365-2958.2001.02291.x. ISSN 1365-2958. PMID 11251819.
7. ^ a b c Phadtare, S., Alsina, J., & Inouye, M. (1999). “Cold-shock response and cold-shock proteins”. Current Opinion in Microbiology. 2(2), 175-180. doi:10.1016/S1369-5274(99)80031-9
8. ^ a b c Phadtare, Sangita (2004). "Recent developments in bacterial cold-shock response". Current Issues in Molecular Biology. 6 (2): 125–136. ISSN 1467-3037. PMID 15119823.
9. ^ Di Pietro, Fabio; Brandi, Anna; Dzeladini, Nadire; Fabbretti, Attilio; Carzaniga, Thomas; Piersimoni, Lolita; Pon, Cynthia L; Giuliodori, Anna Maria (2013). "Role of the ribosome-associated protein PY in the cold-shock response of Escherichia coli". MicrobiologyOpen. 2 (2): 293–307. doi:10.1002/mbo3.68. ISSN 2045-8827. PMC 3633353. PMID 23420694.
10. ^ a b c Keto-Timonen, Riikka; Hietala, Nina; Palonen, Eveliina; Hakakorpi, Anna; Lindström, Miia; Korkeala, Hannu (2016). "Cold Shock Proteins: A Minireview with Special Emphasis on Csp-family of Enteropathogenic Yersinia". Frontiers in Microbiology. 7: 1151. doi:10.3389/fmicb.2016.01151. ISSN 1664-302X. PMC 4956666. PMID 27499753.
11. ^ Phadtare, Sangita; Inouye, Masayori (October 2004). "Genome-wide transcriptional analysis of the cold shock response in wild-type and cold-sensitive, quadruple-csp-deletion strains of Escherichia coli". Journal of Bacteriology. 186 (20): 7007–7014. doi:10.1128/JB.186.20.7007-7014.2004. ISSN 0021-9193. PMC 522181. PMID 15466053.
12. ^ a b Dash, Suchintak; Palma, Cristina S D; Baptista, Ines S C; Almeida, Bilena L B; Bahrudeen, Mohamed N M; Chauhan, Vatsala; Jagadeesan, Rahul; Ribeiro, Andre S (2022-08-03). "Alteration of DNA supercoiling serves as a trigger of short-term cold shock repressed genes of E. coli". Nucleic Acids Research. 50 (15): 8512–8528. doi:10.1093/nar/gkac643. ISSN 0305-1048. PMC 9410904. PMID 35920318.

Sources

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• Introduction to Frozen Mythbusters and Myth #1. Wilderness Medicine Newsletter. Sourced 2008-05-17.

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History of underwater diving History of decompression research and development History of dive computers History of Diving Museum History of scuba diving List of researchers in underwater diving Lyons Maritime Museum Man in the Sea Museum Timeline of atmospheric diving suits Timeline of diving technology Pearling in Western Australia US Navy decompression models and tables Archeologicalsites SS Commodore USS Monitor Queen Anne's Revenge Whydah Gally Underwater artand artists The Diver Jason deCaires Taylor Engineersand inventors Jerónimo de Ayanz y Beaumont William Beebe Georges Beuchat Giovanni Alfonso Borelli Joseph-Martin Cabirol John R. Clarke Jacques Cousteau Charles Anthony Deane John Deane Louis de Corlieu Auguste Denayrouze Ted Eldred Henry Fleuss Émile Gagnan Karl Heinrich Klingert Peter Kreeft Christian J. Lambertsen Yves Le Prieur John Lethbridge Ernest William Moir Joseph Salim Peress Auguste Piccard Joe Savoie Willard Franklyn Searle Gordon Smith Augustus Siebe Pierre-Marie Touboulic Jacques Triger Historicalequipment Aqua-Lung RV Calypso SP-350 Denise Magnesium torch Nikonos Porpoise regulator Standard diving dress Sub Marine Explorer Vintage scuba Diverpropulsionvehicles Advanced SEAL Delivery System Cosmos CE2F series Dry Combat Submersible Human torpedo Motorised Submersible Canoe Necker Nymph R-2 Mala-class swimmer delivery vehicle SEAL Delivery Vehicle Shallow Water Combat Submersible Siluro San Bartolomeo Welfreighter Wet Nellie Military andcovert operations Raid on Alexandria (1941) Sinking of the Rainbow Warrior Scientific projects 1992 cageless shark-diving expedition Mission 31 Awards and events Hans Hass Award International Scuba Diving Hall of Fame London Diving Chamber Dive Lectures NOGI Awards Women Divers Hall of Fame Incidents Dive boat incidents Sinking of MV Conception Diver rescues Alpazat cave rescue Tham Luang cave rescue Early diving John Day (carpenter) Charles Spalding Ebenezer Watson Freediving fatalities Stephen Keenan Loïc Leferme Audrey Mestre Nicholas Mevoli Natalia Molchanova Offshorediving incidents Byford Dolphin diving bell accident Drill Master diving accident Star Canopus diving accident Stena Seaspread diving accident Venture One diving accident Waage Drill II diving accident Wildrake diving accident Professionaldiving fatalities Roger Baldwin John Bennett Victor F. Guiel Jr. Francis P. Hammerberg Craig M. Hoffman Peter Henry Michael Holmes Johnson Sea Link accident Edwin Clayton Link Gerard Anthony Prangley Per Skipnes Robert John Smyth Albert D. Stover Richard A. Walker Lothar Michael Ward Joachim Wendler Bradley Westell Arne Zetterström Scuba divingfatalities 1973 Mount Gambier cave diving accident Ricardo Armbruster Allan Bridge David Bright Berry L. Cannon Cotton Coulson Cláudio Coutinho E. Yale Dawson Deon Dreyer Milan Dufek Sheck Exley Maurice Fargues Fernando Garfella Palmer Guy Garman Steve Irwin death Jim Jones Henry Way Kendall Artur Kozłowski Yuri Lipski Kirsty MacColl Linnea Mills Agnes Milowka François de Roubaix Chris and Chrissy Rouse Dave Shaw Wesley C. Skiles Dewey Smith Rob Stewart Esbjörn Svensson Josef Velek
Publications Manuals NOAA Diving Manual U.S. Navy Diving Manual Basic Cave Diving: A Blueprint for Survival Underwater Handbook Bennett and Elliott's physiology and medicine of diving Encyclopedia of Recreational Diving The new science of skin and scuba diving Professional Diver's Handbook Basic Scuba Standards andCodes of Practice Code of Practice for Scientific Diving (UNESCO) DIN 7876 IMCA Code of Practice for Offshore Diving ISO 24801 Recreational diving services — Requirements for the training of recreational scuba divers General non-fiction The Darkness Beckons Goldfinder The Last Dive Shadow Divers The Silent World: A Story of Undersea Discovery and Adventure Research List of Divers Alert Network publications Dive guides
Training and registration Divertraining Competence and assessment Competency-based learning Refresher training Skill assessment Diver training standard Diving instructor Diving school Occupational diver training Commercial diver training Military diver training Public safety diver training Scientific diver training Recreational diver training Introductory diving ISO training standards Teaching method Muscle memory Overlearning Stress exposure training Skills Combat sidestroke Diver navigation Diver trim Ear clearing Frenzel maneuver Valsalva maneuver Finning techniques Scuba skills Buddy breathing Low impact diving Diamond Reef System Surface-supplied diving skills Underwater searches Recreationalscubacertificationlevels Core diving skills Advanced Open Water Diver Autonomous diver CMAS* scuba diver CMAS** scuba diver Introductory diving Low Impact Diver Master Scuba Diver Open Water Diver Supervised diver Leadership skills Dive leader Divemaster Diving instructor Master Instructor Specialist skills Rescue Diver Solo diver Diver trainingcertificationand registrationorganisations European Underwater Federation (EUF) International Diving Regulators and Certifiers Forum (IDRCF) International Diving Schools Association (IDSA) International Marine Contractors Association (IMCA) List of diver certification organizations National Oceanic and Atmospheric Administration (NOAA) Nautical Archaeology Society Recreational diver course referral World Recreational Scuba Training Council (WRSTC) Commercial divercertificationauthorities Australian Diver Accreditation Scheme (ADAS) Commercial diver registration in South Africa Divers Institute of Technology Health and Safety Executive (HSE) Department of Employment and Labour Commercial divingschools Divers Academy International Norwegian diver school Free-divingcertificationagencies AIDA International (AIDA) Confédération Mondiale des Activités Subaquatiques (CMAS) Performance Freediving International (PI) Scuba Schools International (SSI) Recreationalscubacertificationagencies American Canadian Underwater Certifications (ACUC) American Nitrox Divers International (ANDI) Association nationale des moniteurs de plongée (ANMP) British Sub-Aqua Club (BSAC) Comhairle Fo-Thuinn (CFT) Confédération Mondiale des Activités Subaquatiques (CMAS) Federación Española de Actividades Subacuáticas (FEDAS) Fédération Française d'Études et de Sports Sous-Marins (FFESSM) Federazione Italiana Attività Subacquee (FIAS) Global Underwater Explorers (GUE) International Association for Handicapped Divers (IAHD) International Association of Nitrox and Technical Divers (IANTD) International Life Saving Federation (ILS) Israeli Diving Federation (TIDF) National Academy of Scuba Educators (NASE) National Association of Underwater Instructors (NAUI) Nederlandse Onderwatersport Bond (NOB) Professional Association of Diving Instructors (PADI) Professional Diving Instructors Corporation (PDIC) Professional Technical and Recreational Diving (ProTec) Rebreather Association of International Divers (RAID) Sub-Aqua Association (SAA) Scuba Diving International (SDI) Scuba Educators International (SEI) Scottish Sub Aqua Club (ScotSAC) Scuba Schools International (SSI) Türkiye Sualtı Sporları Federasyonu (TSSF) United Diving Instructors (UDI) YMCA SCUBA Program Scientific divercertificationauthorities American Academy of Underwater Sciences (AAUS) CMAS Scientific Committee Technical divercertificationagencies American Nitrox Divers International (ANDI) British Sub-Aqua Club (BSAC) Confédération Mondiale des Activités Subaquatiques (CMAS) Diving Science and Technology (DSAT) Federazione Italiana Attività Subacquee (FIAS) International Association of Nitrox and Technical Divers (IANTD) Professional Association of Diving Instructors (PADI) Professional Diving Instructors Corporation (PDIC) Professional Technical and Recreational Diving (ProTec) Rebreather Association of International Divers (RAID) Trimix Scuba Association (TSA) Technical Extended Range (TXR) Cavediving Cave Divers Association of Australia (CDAA) Cave Diving Group (CDG) Global Underwater Explorers (GUE) National Speleological Society#Cave Diving Group (CDG) National Association of Underwater Instructors (NAUI) Technical Diving International (TDI) Military divertraining centres Defence Diving School Navy Diving Salvage and Training Center Underwater Escape Training Unit Military divertraining courses United States Marine Corps Combatant Diver Course
Underwater sports Surface snorkeling Finswimming Snorkeling/breath-hold Spearfishing Underwater football Underwater hockey Australia Turkey Underwater rugby Colombia United States Underwater target shooting Breath-hold Aquathlon Apnoea finswimming Freediving Open Circuit Scuba Immersion finswimming Sport diving Underwater cycling Underwater orienteering Underwater photography Rebreather Underwater photography Sports governingorganisations and federations International AIDA International Confédération Mondiale des Activités Subaquatiques) National AIDA Hellas Australian Underwater Federation British Freediving Association British Octopush Association British Underwater Sports Association Comhairle Fo-Thuinn Federación Española de Actividades Subacuáticas Fédération Française d'Études et de Sports Sous-Marins South African Underwater Sports Federation Türkiye Sualtı Sporları Federasyonu Underwater Society of America) Competitions 14th CMAS Underwater Photography World Championship Underwater Hockey World Championships Underwater Orienteering World Championships Underwater Rugby World Championships
Underwater divers Pioneersof diving Eduard Admetlla i Lázaro Aquanaut Mary Bonnin Amelia Behrens-Furniss James F. Cahill Jacques Cousteau Billy Deans Dottie Frazier Trevor Hampton Hans Hass Dick Rutkowski Teseo Tesei Arne Zetterström Underwaterscientistsarchaeologists andenvironmentalists Michael Arbuthnot Robert Ballard George Bass Mensun Bound Louis Boutan Jeffrey Bozanic Hugh Bradner Cathy Church Eugenie Clark James P. Delgado Sylvia Earle John Christopher Fine George R. Fischer Anders Franzén Honor Frost Fernando Garfella Palmer David Gibbins Graham Jessop Swietenia Puspa Lestari Pilar Luna Robert F. Marx Anna Marguerite McCann Innes McCartney Charles T. Meide Mark M. Newell Lyuba Ognenova-Marinova John Peter Oleson Mendel L. Peterson Richard Pyle Andreas Rechnitzer William R. Royal Margaret Rule Gunter Schöbel Stephanie Schwabe Myriam Seco E. Lee Spence Robert Sténuit Peter Throckmorton Cristina Zenato Scuba recordholders Pascal Bernabé Jim Bowden Mark Ellyatt Sheck Exley Nuno Gomes Claudia Serpieri Krzysztof Starnawski Underwaterfilmmakersand presenters Samir Alhafith David Attenborough Ramón Bravo Jean-Michel Cousteau Richie Kohler Paul Rose Andy Torbet Ivan Tors Andrew Wight James Cameron Underwaterphotographers Doug Allan Tamara Benitez Georges Beuchat Adrian Biddle Jonathan Bird Eric Cheng Neville Coleman Jacques Cousteau John D. Craig Ben Cropp Bernard Delemotte David Doubilet Candice Farmer John Christopher Fine Rodney Fox Ric Frazier Stephen Frink Peter Gimbel Monty Halls Hans Hass Henry Way Kendall Rudie Kuiter Joseph B. MacInnis Luis Marden Agnes Milowka Noel Monkman Pete Oxford Steve Parish Zale Parry Pierre Petit Leni Riefenstahl Peter Scoones Brian Skerry Wesley C. Skiles E. Lee Spence Philippe Tailliez Ron Taylor Valerie Taylor Albert Tillman John Veltri Stan Waterman Michele Westmorland John Ernest Williamson J. Lamar Worzel Underwaterexplorers Caves Graham Balcombe Sheck Exley Martyn Farr Jochen Hasenmayer Jill Heinerth Jarrod Jablonski William Hogarth Main Tom Mount Jack Sheppard Bill Stone Reefs Arthur C. Clarke Wrecks Leigh Bishop John Chatterton Clive Cussler Bill Nagle Valerie van Heest Aristotelis Zervoudis Aquanauts Andrew Abercromby Joseph M. Acaba Clayton Anderson Richard R. Arnold Serena Auñón-Chancellor Michael Barratt (astronaut) Robert A. Barth Robert L. Behnken Randolph Bresnik Timothy J. Broderick Justin Brown Berry L. Cannon Scott Carpenter Gregory Chamitoff Steve Chappell Catherine Coleman Robin Cook Craig B. Cooper Fabien Cousteau Philippe Cousteau Timothy Creamer Jonathan Dory Pedro Duque Sylvia Earle Jeanette Epps Sheck Exley Albert Falco Andrew J. Feustel Michael Fincke Satoshi Furukawa Ronald J. Garan Jr. Michael L. Gernhardt Christopher E. Gerty David Gruber Chris Hadfield Jeremy Hansen José M. Hernández John Herrington Paul Hill Akihiko Hoshide Mark Hulsbeck Emma Hwang Norishige Kanai Les Kaufman Scott Kelly Karen Kohanowich Timothy Kopra Dominic Landucci Jon Lindbergh Kjell N. Lindgren Michael López-Alegría Joseph B. MacInnis Sandra Magnus Thomas Marshburn Matthias Maurer K. Megan McArthur Craig McKinley Jessica Meir Simone Melchior Dorothy Metcalf-Lindenburger Andreas Mogensen Karen Nyberg John D. Olivas Takuya Onishi Luca Parmitano Nicholas Patrick Tim Peake Thomas Pesquet Marc Reagan Garrett Reisman Kathleen Rubins Dick Rutkowski Tara Ruttley David Saint-Jacques Josef Schmid Robert Sheats Dewey Smith Steve Squyres Heidemarie Stefanyshyn-Piper Robert Sténuit Hervé Stevenin Nicole Stott James Talacek Daniel M. Tani Robert Thirsk Bill Todd Mark T. Vande Hei Koichi Wakata Rex J. Walheim Shannon Walker John Morgan Wells Joachim Wendler Douglas H. Wheelock Peggy Whitson Dafydd Williams Jeffrey Williams Sunita Williams Reid Wiseman Kimiya Yui Writers and journalists Michael C. Barnette Victor Berge Philippe Diolé Gary Gentile Bret Gilliam Bob Halstead Hillary Hauser Trevor Jackson Steve Lewis John Mattera Rescuers Craig Challen Richard Harris Rick Stanton John Volanthen Frogmen Lionel Crabb Ian Edward Fraser Sydney Knowles James Joseph Magennis Commercial salvors Keith Jessop
Science of underwater diving List of researchers in underwater diving Divingphysics Metre sea water Neutral buoyancy Underwater acoustics Modulated ultrasound Underwater vision Underwater computer vision Divingphysiology Blood shift Cold shock response Diving reflex Equivalent narcotic depth Maximum operating depth Physiological response to water immersion Thermal balance of the underwater diver Underwater vision Work of breathing Decompressiontheory Decompression models: Bühlmann decompression algorithm Haldane's decompression model Reduced gradient bubble model Thalmann algorithm Thermodynamic model of decompression Varying Permeability Model Equivalent air depth Oxygen window Physiology of decompression Divingenvironments Underwater exploration Deep-sea exploration Classification List of diving environments by type Altitude diving Benign water diving Confined water diving Deep diving Inland diving Inshore diving Muck diving Night diving Open-water diving Black-water diving Blue-water diving Penetration diving Cave diving Torricellian chamber Ice diving Wreck diving Recreational dive sites Underwater environment Underwater diving environment Impact Environmental impact of recreational diving Low impact diving
Other Bathysphere Defense against swimmer incursions Diver detection sonar Offshore survey Rugged compact camera Underwater domain awareness Underwater vehicle Deep-submergencevehicle Aluminaut DSV Alvin American submarine NR-1 Bathyscaphe Archimède FNRS-2 FNRS-3 Harmony class bathyscaphe Sea Pole-class bathyscaphe Trieste II Deepsea Challenger Ictineu 3 JAGO Jiaolong Konsul-class submersible Limiting Factor Russian submarine Losharik Mir Nautile Pisces-class deep submergence vehicle DSV Sea Cliff DSV Shinkai DSV Shinkai 2000 DSV Shinkai 6500 DSV Turtle DSV-5 Nemo Submarine rescue International Submarine Escape and Rescue Liaison Office Submarine Escape and Rescue system (Royal Swedish Navy) McCann Rescue Chamber Submarine rescue ship Deep-submergencerescue vehicle LR5 LR7 MSM-1 Mystic-class deep-submergence rescue vehicle DSRV-1 Mystic DSRV-2 Avalon NATO Submarine Rescue System Priz-class deep-submergence rescue vehicle Russian deep submergence rescue vehicle AS-28 Russian submarine AS-34 ASRV Remora SRV-300 Submarine Rescue Diving Recompression System Type 7103 DSRV URF (Swedish Navy) Submarine escape Escape trunk Submarine escape training facility Submarine Escape Training Facility (Australia) Escape set Davis Submerged Escape Apparatus Momsen lung Steinke hood Submarine Escape Immersion Equipment Specialinterestgroups Artificial Reef Society of British Columbia CMAS Europe Coral Reef Alliance Divers Alert Network Green Fins Finger Lakes Underwater Preserve Association Karst Underwater Research Nautical Archaeology Program Nautical Archaeology Society Naval Air Command Sub Aqua Club PADI AWARE Reef Check Reef Life Survey Rubicon Foundation Save Ontario Shipwrecks SeaKeys Sea Research Society Society for Underwater Historical Research Society for Underwater Technology Underwater Archaeology Branch, Naval History & Heritage Command Neutral buoyancyfacilities forAstronaut training Neutral Buoyancy Laboratory Neutral buoyancy pool Neutral buoyancy simulation as a training aid Neutral Buoyancy Simulator Space Systems Laboratory Yuri Gagarin Cosmonaut Training Center Other Nautilus Productions Helicopter Aircrew Breathing Device Scuba diving therapy Seabed mining
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