Sökning: "Per Roos"
Visar resultat 1 - 5 av 11 avhandlingar innehållade orden Per Roos.
1. 231Pa and Th isotopes as tracers of deep water ventilation and scavenging in the Mediterranean Sea
Sammanfattning : The naturally occurring isotopes 231Pa and 230Th are used as tracers of marine biogeochemical processes. They are both produced from the radioactive decay of their uniformly distributed uranium parents (235U and 234U) in seawater. LÄS MER
Sammanfattning : Water column and sediment profiles of plutonium, americium, thorium and uranium have been obtained in the superanoxic Framvaren fjord, southern Norway. The concentrations of bomb test fallout Pu, Am as well as 'dissolved' Th in the bottom water are the highest recorded in the marine environment. LÄS MER
Sammanfattning : A slow but steady increase in neurodegenerative disorders has been noted in recent decades. Degenerations in the nervous system are found in Alzheimer´s disease, Parkinson´s disease and motor neuron diseases. Amyotrophic lateral sclerosis (ALS) is the most common of the motor neuron diseases. LÄS MER
4. Manganese and Iron Heterodimers and Homodimers in Enzymes : Insights from Density Functional Theory
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
5. Iodine Isotopes and their Species in Surface Water from the North Sea to the Northeastern Atlantic Ocean
Sammanfattning : Huge amounts of anthropogenic 129I have been and still are released to the environment through liquid and gaseous discharges from the nuclear fuel reprocessing facilities worldwide and in particular the ones in Europe. Most of this 129I signal has been accumulated in the marine environment which plays a major role in the iodine natural pool. LÄS MER