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Transport and release of insulin granules during biphasic insulin secretion

Glucose-evoked insulin secretion exhibits two phases: The first phase represents exocytosis of insulin granules situated at the plasma membrane, whereas the second phase reflects insulin release from granules continuously recruited to the plasma membrane. This thesis investigates different aspects of phasic insulin secretion, with the specific aims to elucidate the possible contribution of insulin

DYNAMIC MODELLING OF BIOGEOCHEMICAL PROCESSES IN FOREST ECOSYSTEMS

Popular Abstract in Swedish Under de senaste decennierna har våra skogar utsatts för en allt högre grad av stress som en följd av förändrade produktionsmönster och en hög deposition av gödande och försurande ämnen, såsom kväve ovh svavel. Kväve är det ämne som begränsar trädens tillväxt, och det höga nedfallet av detta ämne har resulterat i att träden växt mycket snabbbare. Deras behov av andra näForests in Sweden are undergoing rapid and considerable changes regarding both management methods and environmental conditions. To understand the effects of these changes and to be able to predict impending changes in forest ecosystems, a holistic understanding of the processes governing the ecosystem is needed. To gain such an understanding, the ForSAFE model of the biogeochemical cycles in a for

A method to determine the dynamic load distribution in a chain drive

This paper presents a method to calculate the forces in a chain and, thus, the resulting load distribution along the sprockets in a chain transmission working at a moderate or high speed. When the chain drive is loaded, the rollers that contact the sprockets will move along the flanks to different height positions. There are mainly two different ways to determine the actual positions: to assume th

Dictyostelium discoideum salvages purine deoxyribonucleosides by highly specific bacterial-like deoxyribonucleoside kinases

The salvage of deoxyribonucleosides in the social amoeba Dictyostelium discoideum, which has an extremely A + T-rich genome, was investigated. All native deoxyribonucleosides were phosphorylated by D. discoideum cell extracts and we subcloned three deoxyribonucleoside kinase (dNK) encoding genes. D. discoideum thymidine kinase was similar to the human thymidine kinase 1 and was specific for thymid

Direct electron transfer between ligninolytic redox enzymes and electrodes

The electrochemistry of the ligninolytic redox enzymes, which include lignin peroxidase, manganese peroxidase and laccase and possibly also cellobiose dehydrogenase, is reviewed and discussed in conjunction with their basic biochemical characteristics. It is shown that long-range electron transfer between these enzymes and electrodes can be established and their ability to degrade lignin through a

Dietary factors influence the recovery rates of Helicobacter pylori in a BALB/cA mouse model

The aim of this study was to assess the ability of different mouse diets to sustain an H. pylori infection in BALB/cA mice. Four commercially available mouse diets were compared. Experiment 1: Mice were fed the four diets for seven days before infection, infected three times at two-day intervals with 0.1 ml of 10(9) colony-forming units/ml H. pylori cells. H. pylori strains (n = 4) were cultured o

Petrographic classification of middle ordovician fossil meteorites from Sweden

The maximum diameter of chromite (FeCr2O4) grains within L chondrites reflects the petrographic type of the sample. On the basis of our measurements of nine recent L chondrites, L3 chromite D-mac = 34-50 mu m, L4 = 87-150 mu m, L5 = 76-158 mu m, and L6 = 253-638 mu m. This variation reflects the crystallization of the chromite grains during parent body thermal metamorphism.We use this calibration

If nuchal translucency screening is combined with first-trimester serum screening the need for fetal karyotyping decreases

Background. This case-control study was performed to evaluate whether adding first-trimester maternal serum testing to nuchal translucency measurement would improve the antenatal detection of Down's syndrome and decrease the number of women offered fetal karyotyping. Methods. In the Swedish Nuchal Translucency Trial 39,572 pregnant women were randomized to a routine scan at 12-14 gestational weeks

The hydration of a DNA-amphiphile complex

We present measurements of isothermal DNA-hexadecyltrimethylammonium (DNACTA) complex and pure DNA hydration at 25 degreesC using a sorption microcalorimeter. This calorimeter provides simultaneous measurement of (i) water activity (sorption isotherms) and (ii) the partial molar enthalpy of water as a function of water uptake. For pure DNA, hydration is exothermic over the studied concentration ra

Spatial distribution of polybrominated diphenyl ethers in southern Ontario as measured in indoor and outdoor window organic films

Organic films were collected from indoor and outdoor window surfaces, along an urban-rural transect extending northward from Toronto, Ontario, Canada, and analyzed for 41 polybrominated diphenyl ether congeners (PBDE). For exterior films, urban SigmaPBDE concentrations were similar to10x greater than rural concentrations, indicating an urban-rural gradient and greater PBDE sources in urban areas.

Effects of iso- and hypervolemic hemodilution on regional cerebral blood flow and oxygen delivery for patients with vasospasm after aneurysmal subarachnoid hemorrhage.

SUMMARY:BACKGROUND: Arterial vasospasm after subarachnoid hemorrhage may cause cerebral ischemia. Treatment with hemodilution, reducing blood viscosity, and hypervolemia, increasing cardiac performance and distending the vasospastic artery, are clinically established methods to improve blood flow through the vasospastic arterial bed.METHOD: Eight patients with transcranial Doppler verified vasospa

Problems associated with the determination of heterocyclic amines in cooked foods and human exposure.

Epidemiological studies have shown diet to be an important factor in the global variation of human cancer rates. The presence of mutagenic/carcinogenic heterocyclic aromatic amines (HAs) in cooked foods has attracted a great deal of interest for more than 20 years. Accurate assessment of the human exposure to HAs requires food questionnaires that address cooking methods and reliable methods for th

On Development and Characterisation of Continuous Ink Jet Nozzles

This thesis concerns nozzles and their impact on droplet formation and droplet flight in a continuous ink jet printer. Methods are suggested to characterise droplet formation and droplet flight stability (D.F.S.). A study about the influence of droplet flight stability on the quality of print out is presented. A method to assess the charging process for the continuous ink jet is described. The dev