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The stars of the Galactic center

We consider the origin of the so-called S stars orbiting the supermassive black hole at the very center of the Galaxy. These are usually assumed to be massive main-sequence stars. We argue instead that they are the remnants of low-to-intermediate mass red giants that have been scattered into near-radial orbits and tidally stripped as they approach the central black hole. Such stars retain only low

Lysophosphatidic Acid Binds to and Activates GPR92, a G Protein-Coupled Receptor Highly Expressed in Gastrointestinal Lymphocytes

Here, the ligand binding, activation, and tissue distribution of the orphan G protein-coupled receptor (GPCR) GPR92 were studied. GPR92 binds and is activated by compounds based on the lysophosphatidic acid (LPA) backbone. The binding of LPA to GPR92 was of high affinity (K(D) = 6.4 +/- 0.9 nM) and led to an increase in both phosphoinositide hydrolysis and cAMP production. GPR92 is atypical in tha

A focused antibody library for improved hapten recognition

The topography of the antigen-binding site as well as the number and the positioning of the antigen contact residues are strongly correlated with the size of the antigen with which the antibody interacts. On the basis of these considerations, we have designed a focused scFv repertoire biased for haptens, designated the cavity library. The hapten-specific scFv, FITC8, was used as a scaffold for lib

Charge Sampling Circuits and A/D Converters - Theory and Experiments

The analysis of general charge sampling technique is presented in this thesis. Charge sampling integrates input current instead of tracking input voltage to realize high speed and low voltage sampling. The analysis focuses on the performance of general charge sampling circuits for signal capture. The theoretical analysis here can be applied not only for the weak signal capture, but also for the no

CHICSi - a compact ultra-high vacuum compatible detector system for nuclear reaction experiments at storage rings. III. readout system

(CHICSi) Celsius Heavy Ion Collaboration Si detector system is a high granularity, modular detector telescope array for operation around the cluster-jet target/circulating beam intersection of the CELSIUS storage ring at the The. Svedberg Laboratory in Uppsala, Sweden. It is able to provide identity and momentum vector of up to 100 charged particles and fragments from proton-nucleus and nucleus-nu

Nano-scale Schottky contacts: ultrafast drift-diffusion dynamics studied in the optical near field

We present direct measurements of the ultrafast carrier dynamics around buried nano-scale Schottky contacts with high spatial and time resolution, performed with a novel fermosecond near-field scanning optical microscope, It is shown that high optically excited carrier densities screen the built-in field around a Schottky contact and allow for efficient transport of electrons towards the contact,

Clinical impact of breakpoint position within M-bcr in chronic myeloid leukemia

We have analyzed the M-bcr breakpoint position in 133 Philadelphia-positive chronic myeloid leukemia patients and correlated the findings with clinical, hematologic, and cytogenetic data. We also investigated the splicing pattern of the BCR-ABL mRNA in 30 patients, using reverse transcriptase PCR. No statistically significant differences were found between breakpoint position within M-bcr and clin

Tight coupling between electrical activity and exocytosis in mouse glucagon-secreting alpha-cells

alpha-Cells were identified in preparations of dispersed mouse islets by immunofluorescence microscopy. A high fraction of alpha-cells correlated with a small cell size measured as the average cell diameter (10 microm) and whole-cell capacitance (<4 pF). The alpha-cells generated action potentials at a low frequency (1 Hz) in the absence of glucose. These action potentials were reversibly inhibite

Oscillator strengths for transitions in As II

Theoretical oscillator strengths for transitions between the even 4s(2) 4p(2) and the three odd {4s4p(3), 4s(2)4p4d, 4s(2)4p5s} configurations of As+ are reported. Both ab initio, multiconfiguration Hartree-Fock and semiempirical configuration interaction techniques are used. The uncertainty of the results are estimated, by considering the reproduced energy structure, the agreement of results from

Intracellular signaling and cellular plasticity in a rat model of L-DOPA-induced dyskinesia

Popular Abstract in Swedish Parkinsons sjukdom beror på att de dopamin-producerande cellerna i hjärnan dör. Detta leder till minskad rörlighet, svårigheter i att påbörja och avsluta en rörelse, balanssvårigheter och darrningar (tremor) hos de drabbade patienterna. Varför dopamincellerna dör är oklart och i nulägat kan man inte bota Parkinsons sjukdom, men man kan lindra symptomen med mediciner. PaParkinson's disease (PD) is a neurodegenerative disorder where the midbrain dopaminergic neurons are lost. Presently there is no cure for PD, and the most common treatment is to replace the lost dopamine pharmacologically by administration of the dopamine precursor L-DOPA. This works very well during the initial treatment period, but unfortunately a majority of the patients develop abnormal involu

Outcomes following a programme for lifestyle changes with people with hypertension

AIM: The purpose of the study was to explore the effects of using a structured nursing intervention programme in hypertension care. BACKGROUND: Counselling on lifestyle changes to address hypertension helps patients reduce risk factors such as smoking, high alcohol consumption, overweight, dyslipidemia, negative stress and physical inactivity. DESIGN: The study was performed as a pre-test-post-tes

The evolution of n-player cooperation—threshold games and ESS bifurcations

An evolutionary game of individuals cooperating to obtain a collective benefit is here modelled as an n-player Prisoner's Dilemma game. With reference to biological situations, such as group foraging, we introduce a threshold condition in the number of cooperators required to obtain the collective benefit. In the simplest version, a three-player game, complex behaviour appears as the replicator dy

The Alevi-Bektasi Legacy: Problems of Acquisition and Explanation

Popular Abstract in Swedish Det mystika arvet: om konsten att erhålla och förklara det (och förstå litegrann): Ett turkiskt exempel.Mystics and amateur politicians in the margin of Turkish society. The specific case of marginalisation in the specific context of my choice provides a wealth of details to be accounted for. All details taken together are real life itself and can thus not be accounted for in a book. Enough can be said, however, about marginalisation in general in order for a meaningful discussion to take place. Bu

Investigations into the BFKL mechanism with a running QCD coupling

We present approximations of varying degree of sophistication to the integral equations for the (gluon) structure functions of a hadron ("the partonic flux factor") in a model valid in the leading log approximation with a running coupling constant. The results are all of the BFKL type, i.e., a power in the Bjorken variable x(B)(-lambda) with the parameter lambda determined from the size alpha(0) o

Comparison of xylose fermentation by Saccharomyces cerevisiae strains carrying either xylose reductase and xylitol dehydrogenase or xylose isomerase

Background: Two heterologous pathways have been used to construct recombinant xylose-fermenting Saccharomyces cerevisiae strains: i) the xylose reductase ( XR) and xylitol dehydrogenase (XDH) pathway and ii) the xylose isomerase (XI) pathway. In the present study, the Pichia stipitis XR-XDH pathway and the Piromyces XI pathway were compared in an isogenic strain background, using a laboratory host

Expression and regulation of CCL25 and its role in T cell localization to and function within the small intestine

Earlier studies have demonstrated an important role for the chemokine CCL25, and its receptor CCR9, in the generation of the small intestinal lymphocyte compartment. The work in this thesis was aimed at determining how CCL25 is regulated within the small intestinal mucosa, and what potential role it plays in T cell localization to and function within this site. We have identified epithelial cells