Sökning: "Lena Ma"

Hittade 5 avhandlingar innehållade orden Lena Ma.

  1. 1. Arsenic accumulation in plants for food and phytoremediation : Influence by external factors

    Författare :Claes Bergqvist; Maria Greger; Sylvia Lindberg; Lena Ma; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Arsenic; accumulation; availability; distribution; habitat; phy-toremediation; rhizosphere; redox potential; speciation; Plant Physiology; växtfysiologi;

    Sammanfattning : Arsenic (As) appears in the environment as various As species, which may vary in plant uptake and toxicity. Moreover, As exposure may vary between habitat due to availability and speciation, both of which are influenced by redox potential. To decrease As uptake, addition of silicate may be a tool. LÄS MER

  3. 2. Geochronology of the Oklo and Bangombé fossil natural fission reactors : tracing the effects of geological events

    Författare :Lena Zetterström Evins; Ian Williams; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Historisk geologi; Geology; geologi; geokemi; Geochemistry;

    Sammanfattning : Thesis to be publicly defended for the degree of Doctor of Philosophy, in lecture room De Geersalen, Svante Arrhenius väg 8a, Stockholm, Friday February 1, 2002 at 10.00 am. Two billion years ago, natural fission reactions took place in the Oklo and Bangombé uranium ores in Gabon, West Equatorial Africa. LÄS MER

  4. 3. Early structural and metamorphic evolution of the Scandinavian Caledonides: a study of the eclogite-bearing Seve Nappe Complex at the Arctic Circle, Sweden

    Författare :Lena Gunlög Albrecht; Berggrundsgeologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; oblique compression.; C -type shear bands; anastomozing shear zones; tubular folds; lineation-parallel folds; northern Sweden; Grapesvare Nappe; Seve Nappe Complex; Finnmarkian; Eclogite; corona dolerite; Petrology; mineralogy; geochemistry; Petrologi; mineralogi; geokemi;

    Sammanfattning : In the Seve Nappe Complex of the Swedish Caledonides, coronitic diabases pass into eclogites; sometimes the transition occurs within one and the same boudin. Calculated pressure-temperature conditions for the eclogite facies stage are 20-27 kbar and 650-750°. LÄS MER

  5. 4. Factors influencing the metabolism of inorganic arsenic in humans

    Författare :Anna-Lena Lindberg; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :Arsenic; AS3MT; Gender differences; GSTO1; Metabolism; Methylation; MTHFR; Nutrition; Polymorphisms;

    Sammanfattning : Inorganic arsenic (iAs), a naturally occurring drinking water contaminant, is a potent human carcinogen and toxicant. It is believed that in humans, as well as in most mammals, inorganic arsenic is biotransformed via reduction and methylation using one-carbon metabolism with S-adenosyl methionine (SAM) as methyl donor, and is excreted mainly in urine as dimethylarsinate (DMA) and methylarsonate (MA) as well as some unmethylated iAs (arsenate (As(V)) and arsenite (As(III)). LÄS MER

  7. 5. Acupuncture for labour pain

    Författare :Linda Vixner; Lena Mårtensson; Erica Schytt; Elisabet Stener-Victorin; Ulla Waldenström; Mats Hammar; Högskolan Dalarna; Karolinska Institutet; Karolinska Institutet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; acupuncture; labour pain; randomised controlled trial; Hälsa och välfärd; Health and Welfare;

    Sammanfattning : Background: Acupuncture involves puncturing the skin with thin sterile needles at defined acupuncture points. Previous studies are inconclusive regarding the effect of acupuncture on labour pain, but some studies have found a reduction in the use of pharmacological pain relief when acupuncture is administered. LÄS MER