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We have monitored electrical activity, voltage-gated Ca2+ currents, and exocytosis in single rat glucagon-secreting pancreatic A-cells. The A-cells were electrically excitable and generated spontaneous Na+- and Ca2+-dependent action potentials. Under basal conditions, exocytosis was tightly linked to Ca2+ influx through omega-conotoxin-GVIA-sensitive (N-type) Ca2+ channels. Stimulation of the A-ce

The possibility to prepare fused tetrazole- and imidazole derivatives by iodocyclization in moderate to excellent yields is demonstrated. In some examples the cyclizations were not following Baldwin's rules entirely, i.e. exo-selectivity. Nucleophilic substitution of the formed iodides gave different results depending on the hardness of the nucleophile. Thus, elimination of the iodide could be a p

Abstract is not available

We have investigated spin accumulation in Ni/Au/Ni single-electron transistors assembled by atomic force microscopy. The fabrication technique is unique in that unconventional hybrid devices can be realized with unprecedented control, including real-time tunable tunnel resistances. A grid of Au disks, 30 nm in diameter and 30 nm thick, is prepared on a SiO2 surface by conventional e-beam writing.

An overview on activities to determine unintegrated parton density functions is given and the concept and need for unintegrated PDFs is discussed. It is also argued that it is important to reformulate perturbative QCD results in terms of fully unintegrated parton densities, differential in all components of the parton momentum. Also the need for non-linear BFKL evolution is discussed and results u

This thesis presents a study on performance analysis and optimal design of heat exchangers and heat exchanger networks. The study includes an experimental investigation of steam condensation in plate heat exchangers, optimal design of plate heat exchangers and plate-fin heat exchangers, and optimization of heat exchanger networks. In the experimental investigation of steam condensation in plate h

This paper describes flavour independent searches for hadronically decaying neutral Higgs bosons in the data collected by the DELPHI experiment at LEP, at centre-of-mass energies between 189 and 209 GeV. The collected data-set corresponds to an integrated luminosity of around 610 pb(-1). The e(+)e(-) -> hA and e(+)e(-) -> hZand processes are considered, with direct Higgs boson decays into hadrons.

Aim. Endovascular repair of complicated type B dissections has evolved as a promising alternative to open repair. Previous studies have indicated that continued false lumen flow is a predictor of continued aortic dilatation and risk of rupture during follow-up. This multicenter study was conducted to analyze the postoperative changes of the false lumen after endografting of complicated type B diss

To study the importance of estrogen availability to growth pattern and other tumor characteristic such as estrogen receptor (ER) and progesterone receptor (PgR) content and histopathology, we have used a human tumor-nude mouse model, in which an ER- and PgR-positive and estradiol-sensitive (stimulated) human endometrial adenocarcinoma was heterotransplanted and serially passed in female (non-oopho

Telemedicine is becoming a reality as a result of improvements in technology and telecommunications. The task of the otolaryngological part of the pilot international telemedicine Litmed project was devoted to the establishment of telemedicine training and demonstration facilities in cooperation between the Departments of Otolaryngology of the Kaunas University of Medicine (Lithuania) and the Lund

Popular Abstract in Swedish Två händelser i tumörutvecklingen för en tumörcell är att erhålla okontrollerad celltillväxt och invasiva egenskaper. Detta tillåter tumöran att växa in i den omkringliggande vävnaden. I denna avhandling har vi specifikt studerat p16 och ERK1/2 med speciell fokus på förhållandet mellan invasion och proliferation i hudcancer och bröstcancer. Basalcellscancer har ett disTwo key events in the oncogenic process of tumor cells are to acquire uncontrolled proliferation and invasive properties. This allows the tumor to grow and invade beyond the tissue from which the tumor cells originate. We here specifically studied p16 and ERK1/2 with special focus on and the relation to proliferation and invasion in non-melanoma skin cancer and in breast cancer. In a model system

A combined quantum mechanical-statistical mechanical method has been used to study the behavior of the hydroxyl ion in water. The system is divided into three parts, a quantum core (the ion), 89 classical water molecules, and a dielectric continuum. The water molecules are represented using a polarizable potential. The first solvation shell consists of four water molecules, two linked by hydrogen

Charge pair photogeneration was investigated by ultrafast absorption spectroscopy for different excitation photon energies in poly[3-(2(')-methoxy-5(')octylphenyl)thiophene] (POMeOPT) film with and without an external electric field. Electric field-assisted charge pair photogeneration in POMeOPT occurs from vibrationally relaxed singlet excitons during their entire lifetime and charge pair formati

Recension av Roger Gyllin, Ingvar Svanberg & Ingmar Söhrman (red.); Bröd och salt. Svenska kulturkontakter med öst. En vänbok till Sven Gustavsson.

Popular Abstract in Swedish Hårdvara och algoritmer för ett inbyggt videoövervakningssystem presenteras i denna avhandling. För att verifiera systemet så har en prototyp byggts.The demands on video surveillance systems are rapidly increasing regarding parameters such as frame rate and resolution. Furthermore, with an ever increasing number of video streams, an automated process for extracting relevant information is required. Due to the large amount of input data and the computational complexity of the algorithms, software implementations are not sufficient to sustain re

Characterization of soil respiration rates and δ13C values of soil-respired CO2 are often based on measurements at a particular time of day. A study by Gower et al. (2001) in a boreal forest demonstrated diurnal patterns of soil CO2 flux using transparent measurement chambers that included the understory vegetation. It is unclear whether these diurnal patterns were solely the result of photosynthe

The Wilms' tumor gene 1 (WT1) protein is a transcriptional regulator that is highly expressed in immature hematopoietic progenitor cells and in the majority of patients with acute and chronic myeloid leukemia. However, it is still unclear how WT1 exerts its function(s) in hematopoietic cells. The aim of this work was to investigate the function of WT1 as a transcription factor in human hematopoiet