|
High Altitude Medicine
The effects of high altitude on humans are mostly the consequences of reduced partial pressure of oxygen in the atmosphere. The oxygen saturation of hemoglobin determines the content of oxygen in blood. After the human body reaches around above sea level, the saturation of oxyhemoglobin begins to decrease rapidly. However, the human body has both short-term and long-term adaptations to altitude that allow it to partially compensate for the lack of oxygen. There is a limit to the level of adaptation; mountaineers refer to the altitudes above as the death zone, where it is generally believed that no human body can acclimatize. At extreme altitudes, the ambient pressure can drop below the vapor pressure of water at body temperature, but at such altitudes even pure oxygen at ambient pressure cannot support human life, and a pressure suit is necessary. A rapid depressurisation to the low pressures of high altitudes can trigger altitude decompression sickness. Effects as a func ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
M Rainier
M, or m, is the thirteenth Letter (alphabet), letter in the Latin alphabet, used in the English alphabet, modern English alphabet, the alphabets of other western European languages and others worldwide. Its name in English is English alphabet#Letter names, ''em'' (pronounced ), plural ''ems''. History The letter M is derived from the Phoenician alphabet, Phoenician Mem, via the Greek alphabet, Greek Mu (letter), Mu (Μ, μ). Semitic alphabets, Semitic Mem is most likely derived from a "Proto-Sinaitic script, Proto-Sinaitic" (Bronze Age) adoption of the N-water ripple (n hieroglyph), "water" ideogram in Egyptian hieroglyphs, Egyptian writing. The Egyptian sign had the acrophonic value , from the Egyptian word for "water", ''nt''; the adoption as the Semitic letter for was presumably also on acrophonic grounds, from the Semitic languages, Semitic word for "water", '':wikt:Reconstruction:Proto-Semitic/maʾ-, *mā(y)-''. Use in writing systems The letter represents the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Red Blood Cells
Red blood cells (RBCs), also referred to as red cells, red blood corpuscles (in humans or other animals not having nucleus in red blood cells), haematids, erythroid cells or erythrocytes (from Greek language, Greek ''erythros'' for "red" and ''kytos'' for "hollow vessel", with ''-cyte'' translated as "cell" in modern usage), are the most common type of blood cell and the vertebrate's principal means of delivering oxygen (O2) to the body tissue (biology), tissues—via blood flow through the circulatory system. RBCs take up oxygen in the lungs, or in fish the gills, and release it into tissues while squeezing through the body's capillary, capillaries. The cytoplasm of a red blood cell is rich in hemoglobin, an iron-containing biomolecule that can bind oxygen and is responsible for the red color of the cells and the blood. Each human red blood cell contains approximately 270 million hemoglobin molecules. The cell membrane is composed of proteins and lipids, and this structure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mountaineering
Mountaineering or alpinism, is a set of outdoor activities that involves ascending tall mountains. Mountaineering-related activities include traditional outdoor climbing, skiing, and traversing via ferratas. Indoor climbing, sport climbing, and bouldering are also considered variants of mountaineering by some. Unlike most sports, mountaineering lacks widely applied formal rules, regulations, and governance; mountaineers adhere to a large variety of techniques and philosophies when climbing mountains. Numerous local alpine clubs support mountaineers by hosting resources and social activities. A federation of alpine clubs, the International Climbing and Mountaineering Federation (UIAA), is the International Olympic Committee-recognized world organization for mountaineering and climbing. The consequences of mountaineering on the natural environment can be seen in terms of individual components of the environment (land relief, soil, vegetation, fauna, and landscape) and location/z ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Everest Kalapatthar Crop
Mount Everest (; Tibetan: ''Chomolungma'' ; ) is Earth's highest mountain above sea level, located in the Mahalangur Himal sub-range of the Himalayas. The China–Nepal border runs across its summit point. Its elevation (snow height) of was most recently established in 2020 by the Chinese and Nepali authorities. Mount Everest attracts many climbers, including highly experienced mountaineers. There are two main climbing routes, one approaching the summit from the southeast in Nepal (known as the "standard route") and the other from the north in Tibet. While not posing substantial technical climbing challenges on the standard route, Everest presents dangers such as altitude sickness, weather, and wind, as well as hazards from avalanches and the Khumbu Icefall. , over 300 people have died on Everest, many of whose bodies remain on the mountain. The first recorded efforts to reach Everest's summit were made by British mountaineers. As Nepal did not allow foreigners t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
La Rinconada, Peru
La Rinconada is a town in the Peruvian Andes near a gold mine. At up to above sea level, it is the highest permanent settlement in the world. Between 2001 and 2009, the population was estimated by ''National Geographic'' to have increased to 30,000 people from just a small gold prospector camp because the price of gold rose 235% over that period, although this number has not been reflected by the 2007 or 2017 censuses. Location La Rinconada is a populated center, within the jurisdiction of Ananea District, in San Antonio de Putina Province, Puno Department, Peru. La Rinconada is located in the Janca region, according to the classification of Pulgar Vidal, thus being the highest permanent town in the world. According to the May 2003 issue of ''National Geographic'' magazine, La Rinconada is 5,100 meters above sea level. Occasionally sources claim falsely that it is almost 5,300 meters above sea level. Etymology "La Rinconada" means "The Corner" in Spanish. Geography Topog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dexamethasone
Dexamethasone is a glucocorticoid medication used to treat rheumatic problems, a number of skin diseases, severe allergies, asthma, chronic obstructive lung disease, croup, brain swelling, eye pain following eye surgery, superior vena cava syndrome (a complication of some forms of cancer), and along with antibiotics in tuberculosis. In adrenocortical insufficiency, it may be used in combination with a mineralocorticoid medication such as fludrocortisone. In preterm labor, it may be used to improve outcomes in the baby. It may be given by mouth, as an injection into a muscle, as an injection into a vein, as a topical cream or ointment for the skin or as a topical ophthalmic solution to the eye. The effects of dexamethasone are frequently seen within a day and last for about three days. The long-term use of dexamethasone may result in thrush, bone loss, cataracts, easy bruising, or muscle weakness. It is in pregnancy category C in the United States, meaning that it should ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HACE
High-altitude cerebral edema (HACE) is a medical condition in which the brain swells with fluid because of the physiological effects of traveling to a high altitude. It generally appears in patients who have acute mountain sickness and involves disorientation, lethargy, and nausea among other symptoms. It occurs when the body fails to acclimatize while ascending to a high altitude. It appears to be a vasogenic edema (fluid penetration of the blood–brain barrier), although cytotoxic edema (cellular retention of fluids) may play a role as well. Individuals with the condition must immediately descend to a lower altitude or coma and death can occur. Patients are usually given supplemental oxygen and dexamethasone as well. HACE can be prevented by ascending to heights slowly to allow the body more time to acclimatize. Acetazolamide also helps prevent the condition. Untreated patients usually die within 48 hours. Those who receive treatment may take weeks to fully recover. It is a rar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High-altitude Cerebral Edema
High-altitude cerebral edema (HACE) is a medical condition in which the brain swells with fluid because of the physiological effects of traveling to a high altitude. It generally appears in patients who have acute mountain sickness and involves disorientation, lethargy, and nausea among other symptoms. It occurs when the body fails to acclimatize while ascending to a high altitude. It appears to be a vasogenic edema (fluid penetration of the blood–brain barrier), although cytotoxic edema (cellular retention of fluids) may play a role as well. Individuals with the condition must immediately descend to a lower altitude or coma and death can occur. Patients are usually given supplemental oxygen and dexamethasone as well. HACE can be prevented by ascending to heights slowly to allow the body more time to acclimatize. Acetazolamide also helps prevent the condition. Untreated patients usually die within 48 hours. Those who receive treatment may take weeks to fully recover. It is a rar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HAPE
High-altitude pulmonary edema (HAPE) is a life-threatening form of non-cardiogenic pulmonary edema that occurs in otherwise healthy people at altitudes typically above . However, cases have also been reported between in more vulnerable subjects. Classically, HAPE occurs in persons normally living at low altitude who travel to an altitude above 2,500 meters (8,200 feet). Re-entry HAPE is also an entity that has been described in persons who normally live at high altitude but who develop pulmonary edema after returning from a stay at low altitude. It is severe presentation of altitude sickness. There are many factors that can make a person more susceptible to developing HAPE, including genetic factors, but detailed understanding is lacking and currently under investigation. HAPE remains the major cause of death related to high-altitude exposure, with a high mortality rate in the absence of adequate emergency treatment. Signs and symptoms Physiological and symptomatic changes ofte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High-altitude Pulmonary Edema
High-altitude pulmonary edema (HAPE) is a life-threatening form of non-cardiogenic pulmonary edema that occurs in otherwise healthy people at altitudes typically above . However, cases have also been reported between in more vulnerable subjects. Classically, HAPE occurs in persons normally living at low altitude who travel to an altitude above 2,500 meters (8,200 feet). Re-entry HAPE is also an entity that has been described in persons who normally live at high altitude but who develop pulmonary edema after returning from a stay at low altitude. It is severe presentation of altitude sickness. There are many factors that can make a person more susceptible to developing HAPE, including genetic factors, but detailed understanding is lacking and currently under investigation. HAPE remains the major cause of death related to high-altitude exposure, with a high mortality rate in the absence of adequate emergency treatment. Signs and symptoms Physiological and symptomatic changes ofte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acute Mountain Sickness
Altitude sickness, the mildest form being acute mountain sickness (AMS), is the harmful effect of high altitude, caused by rapid exposure to low amounts of oxygen at high elevation. People can respond to high altitude in different ways. Symptoms may include headaches, vomiting, tiredness, confusion, trouble sleeping, and dizziness. Acute mountain sickness can progress to high-altitude pulmonary edema (HAPE) with associated shortness of breath or high-altitude cerebral edema (HACE) with associated confusion. Chronic mountain sickness may occur after long-term exposure to high altitude. Altitude sickness typically occurs only above , though some are affected at lower altitudes. Risk factors include a prior episode of altitude sickness, a high degree of activity, and a rapid increase in elevation. Diagnosis is based on symptoms and is supported in those who have more than a minor reduction in activities. It is recommended that at high altitude any symptoms of headache, nausea, s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
USARIEM
The U.S. Army Research Institute of Environmental Medicine (USARIEM) is the U.S Army’s main institution and facility for military environmental medicine and exercise physiology research. It is located at Natick, Massachusetts, within the U.S. Army Soldier Systems Center (SSC) installation, but is a subordinate lab of the U.S. Army Medical Research and Materiel Command (USAMRMC), headquartered at Fort Detrick, Maryland, USA. Mission USARIEM’s ''Mission Statement'' mandates that the Institute: The Institute has four divisions, each relating to military human performance as it relates to the environment — Biophysical and Biomedical Modeling, Military Nutrition, Military Performance, and Thermal and Mountain Medicine. Research in the divisions focuses on three elements: the ''servicemember'' (acclimation; body size; gender; race; age; health; hydration; nutrition; fitness; and sleep status), the ''environment'' (temperature; wind; humidity; and altitude), and the ''missi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
