544 research outputs found
Phase diagram at finite temperature and quark density in the strong coupling limit of lattice QCD for color SU(3)
We study the phase diagram of quark matter at finite temperature (T) and
finite chemical potential (mu) in the strong coupling limit of lattice QCD for
color SU(3). We derive an analytical expression of the effective free energy as
a function of T and mu, including baryon effects. The finite temperature
effects are evaluated by integrating over the temporal link variable exactly in
the Polyakov gauge with anti-periodic boundary condition for fermions. The
obtained phase diagram shows the first order phase transition at low
temperatures and the second order phase transition at high temperatures
separated by the tri-critical point in the chiral limit. Baryon has effects to
reduce the effective free energy and to extend the hadron phase to a larger mu
direction at low temperatures.Comment: 18 pages, 10 figure
MarvelD3 regulates the c-Jun N-terminal kinase pathway during eye development in Xenopus.
Ocular morphogenesis requires several signalling pathways controlling the expression of transcription factors and cell-cycle regulators. However, despite a well-known mechanism, the dialogue between those signals and factors remains to be unveiled. Here, we identify a requirement for MarvelD3, a tight junction transmembrane protein, in eye morphogenesis in Xenopus MarvelD3 depletion led to an abnormally pigmented eye or even an eye-less phenotype, which was rescued by ectopic MarvelD3 expression. Altering MarvelD3 expression led to deregulated expression of cell-cycle regulators and transcription factors required for eye development. The eye phenotype was rescued by increased c-Jun terminal Kinase activation. Thus, MarvelD3 links tight junctions and modulation of the JNK pathway to eye morphogenesis
PRELP secreted from mural cells protects the function of blood brain barrier through regulation of endothelial cell-cell integrity
INTRODUCTION:
Proline/arginine-rich end leucine-rich repeat protein (PRELP), is a small secreted proteoglycan expressed by pericytes and vascular smooth muscle cells surrounding the brain vasculature of adult mouse.
METHODS:
We utilised a Prelp knockout (Prelpâ/â) mouse model to interrogate vasculature integrity in the brain alongside performing in vitro assays to characterise PRELP application to endothelial cells lines. Our findings were supplemented with RNA expression profiling to elucidate the mechanism of how PRELP maintains neurovasculature function.
RESULTS:
Prelpâ/â mice presented with neuroinflammation and reducedneurovasculature integrity, resulting in IgG and dextran leakage in the cerebellum and cortex. Histological analysis of Prelpâ/â mice revealed reducedcell-cell integrity of the blood brain barrier, capillary attachment of pericytes andastrocyte end-feet. RNA-sequencing analysis found that cell-cell adhesion andinflammation are affected in Prelpâ/â mice and gene ontology analysis as well as gene set enrichment analysis demonstrated that inflammation related processes and adhesion related processes such as epithelial-mesenchymal transition and apical junctions were significantly affected, suggesting PRELP is a regulator of cell-cell adhesion. Immunofluorescence analysis showed that adhesion junction protein expression levels of cadherin, claudin-5, and ZO-1, was suppressed in Prelpâ/â mice neurovasculature. Additionally, in vitro studies revealed that PRELP application to endothelial cells enhances cell-cell integrity, induces mesenchymal-endothelial transition and inhibits TGF-ÎČ mediated damage to cell-cell adhesion.
DISCUSSION:
Our study indicates that PRELP is a novel endogenous secreted regulator of neurovasculature integrity and that PRELP application may be a potential treatment for diseases associated with neurovascular damage
Prominin-1 Modulates Rho/ROCK-Mediated Membrane Morphology and Calcium-Dependent Intracellular Chloride Flux
Membrane morphology is an important structural determinant as it reflects cellular functions. The pentaspan membrane protein Prominin-1 (Prom1/CD133) is known to be localised to protrusions and plays a pivotal role in migration and the determination of cellular morphology; however, the underlying mechanism of its action have been elusive. Here, we performed molecular characterisation of Prom1, focussing primarily on its effects on cell morphology. Overexpression of Prom1 in RPE-1 cells triggers multiple, long, cholesterol-enriched fibres, independently of actin and microtubule polymerisation. A five amino acid stretch located at the carboxyl cytosolic region is essential for fibre formation. The small GTPase Rho and its downstream Rho-associated coiled-coil-containing protein kinase (ROCK) are also essential for this process, and active Rho colocalises with Prom1 at the site of initialisation of fibre formation. In mouse embryonic fibroblast (MEF) cells we show that Prom1 is required for chloride ion efflux induced by calcium ion uptake, and demonstrate that fibre formation is closely associated with chloride efflux activity. Collectively, these findings suggest that Prom1 affects cell morphology and contributes to chloride conductance
Cosmogenic 11C production and sensitivity of organic scintillator detectors to pep and CNO neutrinos
Several possible background sources determine the detectability of pep and
CNO solar neutrinos in organic liquid scintillator detectors. Among such
sources, the cosmogenic 11C nuclide plays a central role. 11C is produced
underground in reactions induced by the residual cosmic muon flux. Experimental
data available for the effective cross section for 11C by muons indicate that
11C will be the dominant source of background for the observation of pep and
CNO neutrinos. 11C decays are expected to total a rate 2.5 (20) times higher
than the combined rate of pep and CNO neutrinos in Borexino (KamLAND) in the
energy window preferred for the pep measurement, between 0.8 and 1.3 MeV.
This study examines the production mechanism of 11C by muon-induced showers
in organic liquid scintillators with a novel approach: for the first time, we
perform a detailed ab initio calculation of the production of a cosmogenic
nuclide, 11C, taking into consideration all relevant production channels.
Results of the calculation are compared with the effective cross sections
measured by target experiments in muon beams.
This paper also discusses a technique for reduction of background from 11C in
organic liquid scintillator detectors, which allows to identify on a one-by-one
basis and remove from the data set a large fraction of 11C decays. The
background reduction technique hinges on an idea proposed by Martin Deutsch,
who suggested that a neutron must be ejected in every interaction producing a
11C nuclide from 12C. 11C events are tagged by a three-fold coincidence with
the parent muon track and the subsequent neutron capture on protons.Comment: 11 pages, 6 figures; added one section detailing comparison with
previous estimates; added reference
- âŠ