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Northern Europe was capped by ice during Weichsel (Wurm), the maximum of which occurred approximately 18,000 years before present. When in the latter part of the 19(th) century the view of an all-devastating land ice (the tabula rasa hypothesis) was generally adopted by natural scientists, plant biogeographers used a simple model predicting a post-glacial, northwards re-migration of species in con

Antigenic variation of surface proteins allows microorganisms to evade the immune system of the infected host. This phenomenon represents an apparent paradox, because the variable protein must retain an important function, while its antigenic properties vary extensively. The surface associated M protein of Streptococcus pyogenes, a common human pathogen, exhibits antigenic variation due to an N-te

Climate warming is more pronounced in the Arctic than in other parts of the world. This warming affects the terrestrial cryosphere including permafrost with consequences ranging from societal impacts to changes in hydrology and feedbacks in the climate system such as those imposed by changing greenhouse gas exchanges. Permafrost dynamics in a marginal zone for its very existence is in this context

The plant plasma membrane H⁺-ATPase is a predominant membrane enzyme that provides the energy for secondary active transport across the plasma membrane. Consequently, the H⁺-ATPase is thought to play a major role in many cell processes, and it is implicated to be regulated by a number of factors, including hormones, blue light, and fungal toxins The plant plasma membrane H

Popular Abstract in Swedish Sammanfattning Mänskliga aktiviteter och klimatförändringar påverkar vegetationen över hela jorden, idag och i framtiden. Denna påverkan kan studeras och kvantifieras med hjälp av observationer från satelliter vilka förmedlar information om vegetationsförändringar i tid och rum. I denna doktorsavhandling har metoder för analys av vegetationsförändringar utvecklats och Abstract This thesis aims to advance the analysis of nonlinear trends in time series of vegetation data from Earth observation satellite sensors. This is accomplished by developing fast, efficient methods suitable for large volumes of data. A set of methods, tools, and a framework are developed and verified using data from regions containing vegetation change hotspots. First, a polynomial-fittin

An effective uptake/absorption of drug formulations involve many processes; one being the transport of the active molecule through the mucus layer. The mucus layer is a complex mixture of biological molecules. Among them, mucin is the molecule that mainly provides the gel properties of the layer. Thus, the in-vivo physico-chemical properties of the mucus can to a first approximation be mimicked by

Popular Abstract in Swedish En studie av hur glokokortikoider hämmar inflammation Glukokortikosteroider, varav kortison är den mest kända, är hormoner som reglerar många funktioner i kroppen och även används som läkemedel för att dämpa inflammatoriska tillstånd som t.ex. astma och reumatiska sjukdomar. Glukokortikosteroider är mycket potenta läkemedel och används flitigt med mycket goda effekter.The aim of this investigation has been to study mechanisms by which glucocorticoids inhibit inflammatory processes in vitro. Type IV cytosolic 85 kDa phospholipase A2 (cPLA2) is an important modulator of inflammatory responses that is present in macrophages as well as in other cell types. In macrophages, the synthetic glucocorticoid dexamethasone (dex) was found to reduce the expression of cPLA2 a

Skogar har en positiv inverkan på halten av växthusgaser i atmosfären eftersom de binder koldioxid via fotsyntesen och lagrar kol i marken. Dessutom utgör många skogar en betydande sänka för växthusgasen metan. Upptaget av metan sker i väl syresatta marker genom oxidation utförd av metanotrofa bakterier. Däremot sker en nettoproduktion av metan i syrefattiga skogsmarker när mikroorganismer, s.k. aPopular Abstract in English Forests have a positive impact on the level of greenhouse gases in the atmosphere because they absorb carbon dioxide through photosynthesis and store carbon in the soil. Moreover, many forests function as a sink for the greenhouse gas methane (CH4). The uptake of CH4 takes place in well-aerated soils through oxidation by methanotrophic bacteria. However, there is a net

During the latest years the research on the effects of moisture on clothing system has been boosted. New information has revealed phenomena, e.g. “heat pipe” effect with its condensation-evaporation cycle(s) that has not been considered earlier in prediction of physiological reactions or evaluating clothing properties. Considering the material properties, e.g. the evaporative resistance measuremen

Atmospheric organic aerosols are generally classified as primary and secondary (POA and SOA) according to their formation processes. An actual separation, however, is challenging when the timescales of emission and gas-to-particle formation overlap. The presence of SOA formation in biomass burning plumes leads to scientific questions about whether the oxidized fraction of biomass burning aerosol i

Background Acute pyelonephritis is a common infection in adult women, but there is a paucity of controlled trials of its treatment and the optimum duration of antibiotic treatment has not been properly defined. We compared the efficacy of ciprofloxacin for 7 days and 14 days in women with community-acquired acute pyelonephritis. Methods In a prospective, non-inferiority trial undertaken at 21 cent

The levels of heavy metals in surface water and their potential origin (natural and anthropogenic) were respectively determined and analysed for the Obuasi mining area in Ghana. Using Hawth's tool an extension in ArcGIS 9.2 software, a total of 48 water sample points in Obuasi and its environs were randomly selected for study. The magnitude of As, Cu, Mn, Fe, Pb, Hg, Zn and Cd in surface water fro

Expanding hypoxia in the Baltic Sea over the past century has led to the development of anoxic and sulfidic (euxinic) deep basins that are only periodically ventilated by inflows of oxygenated waters from the North Sea. In this study, we investigate the potential consequences of the expanding hypoxia for manganese (Mn) burial in the Baltic Sea using a combination of pore water and sediment analyse

Objectives The study sought to evaluate the relationship between procedural volume and outcomes with radial and femoral approach. Background RIVAL (RadIal Vs. femorAL) was a randomized trial of radial versus femoral access for coronary angiography/intervention (N = 7,021),which overall did not show a difference in primary outcome of death, myocardial infarction, stroke, or non-coronary artery bypa

Thermal-optical analysis is a conventional method for determining the carbonaceous aerosol fraction and for classifying it into organic carbon, OC, and elemental carbon, EC. Unfortunately, the different thermal evolution protocols in use can result in a wide elemental carbon-to-total carbon variation by up to a factor of five. In Europe, there is currently no standard procedure for determining the

PURPOSE:: To describe a family with an 18-year-old woman with fundus albipunctatus and compound heterozygous mutations in RPE65 whose unaffected parents and 1 female sibling harbored single heterozygous RPE65 mutations. DESIGN:: Observational study. PARTICIPANTS:: Four family members. METHODS:: Clinical examinations included full-field electroretinogram (ffERG) after standard (30-minute) and prolo

General obesity, as reflected by BMI, is an established risk factor for esophageal adenocarcinoma (EAC), a suspected risk factor for gastric cardia adenocarcinoma (GCC) and appears unrelated to gastric non-cardia adenocarcinoma (GNCC). How abdominal obesity, as commonly measured by waist circumference (WC), relates to these cancers remains largely unexplored. Using measured anthropometric data fro

Traumatic brain injury (TBI) is one of the leading causes of death in children worldwide. Emerging evidence suggests that alterations in mitochondrial function are critical components of secondary injury cascade initiated by TBI that propogates neurodegeneration and limits neuroregeneration. Unfortunately, there is very little known about the cerebral mitochondrial bioenergetic response from the i