Sökning: "iron"

Visar resultat 21 - 25 av 1581 avhandlingar innehållade ordet iron.

1. 21. Manganese and Iron Heterodimers and Homodimers in Enzymes : Insights from Density Functional Theory

   Författare :Katarina Roos; Per Siegbahn; Margareta R. A. Blomberg; Frank Neese; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Ribonucleotide reductase; manganese; iron; density functional theory; kemisk fysik; Chemical Physics;

   Sammanfattning : The enzyme ribonucleotide reductase (RNR) catalyzes the reduction of ribonucleotides to deoxyribonucleotides, the building blocks of DNA, and is essential for all organisms. Canonical class I RNR R2 proteins use a diiron cofactor to generate a tyrosyl radical, which is required for catalysis. LÄS MER

3. 22. Iron in the Lena River basin, NE Russia : Insights from microscopy, spectroscopy and isotope analysis

   Författare :Catherine Hirst; Carl-Magnus Mörth; Per Andersson; Mats Erik Åström; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; iron; reactivity; isotopes; permafrost; river; Arctic; Marine Geology; maringeologi;

   Sammanfattning : Iron is an important mediator of biotic and abiotic processes on the Earth’s surface, being an electron acceptor in organic matter degradation, a surface for organic matter and trace element adsorption, and a required element for enzymatic processes during primary production. Yet, the role of iron as a mediator of carbon and trace element cycling in high latitude, permafrost-dominated regions remains poorly investigated. LÄS MER

4. 23. Functional Models for Non-heme Mononuclear Iron Oxygenases

   Författare :Mainak Mitra; Kemisk fysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Bioinorganic chemistry; Iron; Oxygenases; Catalysis;

   Sammanfattning : Non-heme mononuclear iron oxygenases catalyze a large number of oxidation reactions in biological systems. The reactions are often proposed to proceed via the intermediacy of high valent Fe(IV) oxo (ferryl) or, Fe(V) oxo (perferryl) intermediates. LÄS MER

5. 24. Landskapsutnyttjande, bete och odling på Sydsvenska höglandet under äldre järnålder. Exemplet Öggestorp. : Land-use, grazing and cultivation in the south Swedish uplands. The Öggestorp case

   Författare :Leif Häggström; Göteborgs universitet; []
   Nyckelord :HUMANIORA; HUMANITIES; Agrarian practice; farming; cultivation; grazing; Pre-Roman Iron Age; Roman Iron Age; source criticism; Småland; south Swedish uplands; forest; woodland; iron; settlement; clearance cairn; crops; technical innovation; archaeological dating methods; centrality; periphery; contract archaeology; cultural heritage management;

   Sammanfattning : Land-use, grazing and cultivation in the south Swedish uplands. The Öggestorp case. Thesis for the degree of Doctor of Philosophy, Göteborg University, Department of Archaeology, 2005. Written in Swedish, with an English summary. LÄS MER

7. 25. Structural Insights into the Acquisition and Storage of Iron

   Författare :Ulrika Schagerlöf; Biokemi och Strukturbiologi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Strukturkemi; Molecular biophysics; Molekylär biofysik; Structure chemistry; single particle; ferric reductase; human phagocyte superoxide-generating NADPH oxidase; frataxin; cryo electron microscopy; FRO2; iron homeostasis; iron acquisition;

   Sammanfattning : It is of vital importance to understand the systems for iron metabolism and this thesis contributes to this by providing insights into the structure and function of the acquisition and homeostasis of iron. The two proteins that have been primarily investigated are a ferric reductase from Arabidopsis thaliana called FRO2 and a mitochondrial iron chaperone from Saccharomyces cerevisiae called frataxin. LÄS MER