Search for dissertations about: "altitude"

Showing result 1 - 5 of 144 swedish dissertations containing the word altitude.

  2. 1. Protective Responses to Freediving Reveal High-Altitude Tolerance

    Author : Pontus Holmström; Erika Schagatay; Angelica Lodin-Sundström; Harald K. Engan; Ola Eiken; Mittuniversitetet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Acclimatization; Acute Mountain Sickness; Adaptation; Apnea; Breath-hold diving; Cardiovascular diving response; High-altitude; Hypoxia tolerance; Spleen; Acklimatisering; Andhållningsdykning; Anpassning; Apné; Kardiovaskulära dykresponsen; Hög höjd; Hypoxitolerans; Hög-höjdssjukdom; Mjälte; Syrebärande kapacitet;

    Abstract : High-altitude mountaineers - just as freedivers - are exposed to hypoxia. During freediving, the diving response leads to reduced oxygen consumption, and splenic contraction increases circulating hemoglobin concentration (Hb), which enhances freediving performance. READ MORE

  4. 2. Decompression strain during long-duration, high-altitude exposures : Effects of intermittent excursions to moderate altitude and inspired fractions of oxygen

    Author : Rickard Ånell; Ola Eiken; Mikael Gennser; Mikael Grönkvist; Ole Hyldegaard; KTH; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Teknik och hälsa; Technology and Health;

    Abstract : Today´s tactical demands and new technical solutions in fighter aircraft entail longer exposure periods at higher altitudes than before. A low cabin pressure protects pilots from pulmonary barotrauma in case of a sudden loss of cabin pressure, however it can also generate a supersaturation of nitrogen (N2) in the tissues, increasing the risks of bubble formation and decompression sickness (DCS). READ MORE

  5. 3. Initiation of spleen contraction resulting in natural blood boosting in humans

    Author : Angelica Lodin; Erika Schagatay; Mats H. Linér; Mittuniversitetet; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Acclimatization; altitude; apnea; breath-hold diving; hemoglobin; hypercapnia; hypoxia; triggers;

    Abstract : The spleen has been shown to contract in apneic situations in humans as well as in other diving mammals, expelling its stored red blood cell content into circulation. This natural blood boosting may increase the circulating hemoglobin concentration (Hb) by up to 10%, which would enhance the oxygen carrying capacity and likely increase performance. READ MORE

  6. 4. The role of herbivores in mediating responses of tundra ecosystems to climate change

    Author : Elina Kaarlejärvi; Johan Olofsson; Anu Eskelinen; Jon Moen; Eric Post; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Climate change; warming; grazer; Rangifer; Lemmus lemmus; species distribution; biotic interactions; altitude; Environmental Science; miljövetenskap;

    Abstract : The Arctic areas are warming more rapidly than other parts of the world. Increasing temperatures are predicted to result in shrubification, higher productivity, declining species diversity and new species invasions to the tundra. READ MORE

  7. 5. Biodiversity patterns and the processes regulating them along elevation gradients in the Swedish mountains

    Author : Johannes Måsviken; Love Dalén; Anne Bjorkman; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; biodiversity; elevation gradients; spiders; insects; plants; latitude; altitude; alpha diversity; beta diversity; taxonomic diversity; phylogenetic diversity; functional diversity; Systematic Zoology; zoologisk systematik och evolutionsforskning;

    Abstract : Biodiversity describes the total variation of life and includes the taxonomic, genetic, and phenotypic differences among organisms. Variations of biodiversity in space and time may be driven by ecological, evolutionary, or neutral processes. READ MORE