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Visar resultat 16 - 20 av 201 avhandlingar som matchar ovanstående sökkriterier.

1. 16. Holocene climate and atmospheric circulation changes in northern Fennoscandia : Interpretations from lacustrine oxygen isotope records

   Författare :Christina E. Jonsson; Gunhild Rosqvist; Jan Seibert; Philip Barker; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; oxygen isotope; diatom silica; lake sediment; atmospheric circulation; North Atlantic Oscillation; northern Fennoscandia; The Holocene; Little Ice Age; Physical geography; Naturgeografi; Physical Geography; naturgeografi;

   Sammanfattning : This thesis investigates how variations in the oxygen isotopic composition of lake waters in northern Fennoscandia are recorded in lake sediment archives, especially diatoms, and how these variations can be used to infer past changes in climate and atmospheric circulation. Results from analyses of the oxygen isotopic composition of lake water samples (δ18Olakew) collected between 2001 and 2006 show that δ18O of northern Fennoscandian lakes is mainly controlled by the isotopic composition of the precipitation (δ18Op). LÄS MER

3. 17. Obstructive sleep apnea syndrome. Treatment outcome, psychiatric aspects, neuropsychology and quality of life

   Författare :Pia Dahlöf; Göteborgs universitet; []
   Nyckelord :obstructive sleep apnea syndrome; uvulopalatopharyngoplasty; oxygen desaturation index; psychiatric morbidity; depression; dexamethasone suppression test; verbal learning and recall; executive functions; quality of life; spouses; long-term follow-up;

   Sammanfattning : Background: Obstructive sleep apnea syndrome (OSAS) is characterized by snoring and apneas during sleep leading to oxygen desaturation, sleep fragmentation and excessive daytime sleepiness. Prior reports have indicated that psychiatric morbidity associated with sleep apnea might be reversed by intervention correcting the sleep related breathing disorder. LÄS MER

4. 18. Causes and treatment of chronic respiratory failure : experience of a national register

   Författare :Torbjörn Gustafson; Kerstin Ström; Karl Franklin; Kjell Torén; Kurt Boman; Leif Bjermer; Umeå universitet; []
   Nyckelord :Internal medicine; Invärtesmedicin; chronic obstructive pulmonary disease; pulmonary fibrosis; kyphoscoliosis; respiratory failure; sex; smoking; occupation; survival; long-term oxygen therapy; mechanical ventilation; lungmedicin; Lung Medicine;

   Sammanfattning : Long-term oxygen therapy (LTOT) or home mechanical ventilation (HMV) can improve survival time in chronic respiratory failure. A national quality register could be an aid to identifying risk markers and optimizing therapy for respiratory failure. LÄS MER

5. 19. Short and long-term effects of exposure to low dose and low dose rate of gamma radiation : using in vitro and in vivo models

   Författare :Traimate Sangsuwan; Siamak Haghdoost; Eva Forssell-Aronsson; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Low dose; Low dose rate; High dose rate; Ionizing radiation; Adaptive response; Senescence; Premature senescence; Oxidative stress; Drosophila embryo; Mutation; DNA repair; molekylär biovetenskap; Molecular Bioscience;

   Sammanfattning : Assessment of human health risks from exposure to ionizing radiation (IR) is mainly based on the extrapolation of results from epidemiological studies on populations exposed to relatively high doses and often at high dose rates (HDR). Risk estimates after exposure to low doses and in particular at low dose rates (LDR) remain controversial due to a lack of epidemiological evidence. LÄS MER

7. 20. Modified oxygen and hydrogen transport in Zr-based oxides

   Författare :Clara Anghel; Gunnar Hultquist; Magnus Limbäck; Truls Norby; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Zirconia; Zirconium; Zircaloy; hydrogen and oxygen diffusion; SPP; oxygen dissociating elements; oxidation; dissociation; hydration; CO adsorption; molecular transport; porosity.; Materials science; Teknisk materialvetenskap;

   Sammanfattning : Most metals and alloys in the presence of oxygen and moisture will instantaneously react and form a thin (2-5 nm) surface oxide layer. For further reaction to occur, oxygen ions and/or metal cations often diffuse through the already formed oxide layer. LÄS MER