11,017 research outputs found
Melatonin receptor expression in the zebra finch brain and peripheral tissues
The circadian endocrine hormone melatonin plays a significant role in many physiological processes such as modulating sleep/wake cycle and oxidative stress. Melatonin is synthesised and secreted during the night by the pineal gland and released into the circulatory system. It binds to numerous membrane, cytosolic and nuclear receptors in the brain and peripheral organs. Three G-protein linked membrane receptors (Mel-1A, Mel-1B and Mel-1C) have been identified in numerous species. Considering the importance of this hormone and its receptors, this study looks at the location and rhythmicity of three avian melatonin receptors Mel-1A, Mel-1B and Mel-1C using reserve transcription-polymerase chain reaction (RT-PCR) mRNA analysis techniques. This study shows successful partial cloning of the three receptors and gene expression analysis revealed significant rhythms of the Mel-1A receptor in the cerebellum, diencephalon, tectum opticum, telencephalon, and retina. Significant rhythms where found in the diencephalon, pineal gland, retina, tectum opticum and cerebellum of the Mel-1B receptor whereas Mel-1C appeared not to be rhythmically expressed in brain tissues studied. Mel-1A, Mel-1B and Mel-1C receptor mRNA where also present in peripheral tissues showing tissue-specific expression patterns
ATAMM analysis tool
Diagnostics software for analyzing Algorithm to Architecture Mapping Model (ATAMM) based concurrent processing systems is presented. ATAMM is capable of modeling the execution of large grain algorithms on distributed data flow architectures. The tool graphically displays algorithm activities and processor activities for evaluation of the behavior and performance of an ATAMM based system. The tool's measurement capabilities indicate computing speed, throughput, concurrency, resource utilization, and overhead. Evaluations are performed on a simulated system using the software tool. The tool is used to estimate theoretical lower bound performance. Analysis results are shown to be comparable to the predictions
Dietzia papillomatosis sp. nov., a novel actinomycete isolated from the skin of an immunocompetent patient with confluent and reticulated papillomatosis
An actinomycete isolated from an immunocompetent patient suffering from confluent and reticulated papillomatosis was characterized using a polyphasic taxonomic approach. The organism had chemotaxonomic and morphological properties that were consistent with its assignment to the genus Dietzia and it formed a distinct phyletic line within the Dietzia 16S rRNA gene tree. It shared a 16S rRNA gene sequence similarity of 98.3 % with its nearest neighbour, the type strain of Dietzia cinnamea, and could be distinguished from the type strains of all Dietzia species using a combination of phenotypic properties. It is apparent from genotypic and phenotypic data that the organism represents a novel species in the genus Dietzia. The name proposed for this taxon is Dietzia papillomatosis; the type strain is N 1280T (=DSM 44961T=NCIMB 14145T)
The role of the NFKB signalling pathway in the inflamed intestine
A Thesis submitted to the University of Luton for the degree of Doctor of PhilosophyThe nuclear factor kappa B (NFKB) signalling pathway is essential in the establishment and propagation of inflammation in the intestine. An increased number of cells, predominantly of the macrophage and intestinal epithelial cell (IEC) type, are known to contain the active form of the NF1d3-p65 subunit in inflamed and noninflamed intestinal tissue from Crahn's disease (CD) patients, though this remains to be confirmed. However the stimuli that induce NFKB activation in IECs and the mechanism of NFKB activation in macrophages, are only poorly understood. As such, this thesis has investigated the NFKB signalling pathway and its role in intestinal inflammation.
Increased levels of NFKB DNA-binding activity and inhibitor kappa B alpha (IKBa) protein levels were found in both inflamed and non-inflamed intestinal tissue from CD patients. However, Bcl-3 levels did not significantly change.
In HeLa Ohio cells, a human mucosal epithelial cell line, interleukin-l ~ (IL-l ~), lipopolysaccharide (LPS) and Phorbol 12-myritate I3-acetate (PMA) were shown to induce NFKB activation. However, when these same stimuli were used in another human IEC line, Caco-2, little NFKB-mediated gene expression was observed unless a combination of stimuli, IL-l~, LPS and tumour necrosis factor alpha (TNFa), was used. In RAW 264.7 cells, a murine macrophage cell line, LPS-stimulated NFKBmediated NO production was shown to involve protein kinase C epsilon (PKCc). Subsequently, PKC€ protein levels were also shown to be up-regulated in inflamed intestinal tissue from TNBS-treated rats. This was associated with increased NFlcB activation and IKBa protein levels, increases that were absent in non~inflamed tissue from TNBS-treated rats. In addition, IKB~ and Bcl-3 protein levels did not differ between inflamed and non-inflamed tissues, although they did vary with intestinal region.
In conclusion, this study shows that abnormal NFKB activation and IKBa expression occurs in CD, and also suggests increased NFKB activation IKBa expression can coexist within inflamed intestinal tissue. In addition, the IEC line Caco-2 is shown to be relatively unresponsive to NFKB activation. In the macrophage cell line, RAW 264.7, PKC£ is involved in NFKB-mediated gene expression, and PKC£ protein levels are increased in the inflamed, TNBS-treated, intestine
Development of a Spatial European Soil Property Data Set
For many applications of modelling environmental conditions or developing scenarios for environmental change analysis soil property data in form of spatial layers are needed. Raster data formats are widely used for the modelling of movements through space and the storage of parameters, which change constantly and without a pattern that could be described by a plain mathematical function. This study into providing spatial soil property layers uses a soil database where the soil properties are stored in tables of generalized combinations of attributes and linked to a spatial layer of delineated mapping units with the aim to investigate the potential of providing a measure of spatial positioning of attributes within spatial mapping units and options of mapping all attributes associated with the mapping unit to a raster layer.
The method developed in the course of the study resulted in a set of spatial data of major soil properties. It also indicates that linking soil morphological data with ancillary spatial information by a multi-criteria analysis could largely improve the mapping of typological soil properties.JRC.H.7-Land management and natural hazard
Magnetic substructure in the northern Fermi Bubble revealed by polarized WMAP emission
We report a correspondence between giant, polarized microwave structures
emerging north from the Galactic plane near the Galactic center and a number of
GeV gamma-ray features, including the eastern edge of the recently-discovered
northern Fermi Bubble. The polarized microwave features also correspond to
structures seen in the all-sky 408 MHz total intensity data, including the
Galactic center spur. The magnetic field structure revealed by the polarization
data at 23 GHz suggests that neither the emission coincident with the Bubble
edge nor the Galactic center spur are likely to be features of the local ISM.
On the basis of the observed morphological correspondences, similar inferred
spectra, and the similar energetics of all sources, we suggest a direct
connection between the Galactic center spur and the northern Fermi Bubble.Comment: Accepted for publication in The Astrophysical Journal Letters after
minor change
Cryo Propulsive Stage: HEFT Phase 2 Point of Departure
The CPS is an in-space high thrust propulsive stage based largely on state of the practice design for launch vehicle upper stages. However, unlike conventional propulsive stages, it also contains power generation and thermal control systems to limit the loss of liquid hydrogen and oxygen due to boil-off during extended in-space storage. The CPS provides high thrust GV for rapid transfer of in-space elements to their destinations or staging points (i.e., E-M L1). The CPS is designed around a block upgrade strategy to provide maximum mission/architecture flexibility: a) Block 1 CPS: Short duration flight times (hours), passive cryofluid management. b) Block 2 CPS: Long duration flight times (days/weeks/months), active and passive cryofluid management
A Demonstration of the Interrelating of Library and Base Education Services for Disadvantaged Adults: Final Report, Kentucky Model Center
1973 annual report of the Demonstration of the Interrelating of Library and Base Education Services for Disadvantaged Adults for Floyd County, Kentucky and published by the Appalachian Adult Education Center at Morehead State University
Wild at Heart:-The Particle Astrophysics of the Galactic Centre
We treat of the high-energy astrophysics of the inner ~200 pc of the Galaxy.
Our modelling of this region shows that the supernovae exploding here every few
thousand years inject enough power to i) sustain the steady-state, in situ
population of cosmic rays (CRs) required to generate the region's non-thermal
radio and TeV {\gamma}-ray emis-sion; ii) drive a powerful wind that advects
non-thermal particles out of the inner GC; iii) supply the low-energy CRs whose
Coulombic collisions sustain the temperature and ionization rate of the
anomalously warm, envelope H2 detected throughout the Cen-tral Molecular Zone;
iv) accelerate the primary electrons which provide the extended, non-thermal
radio emission seen over ~150 pc scales above and below the plane (the Galactic
centre lobe); and v) accelerate the primary protons and heavier ions which,
advected to very large scales (up to ~10 kpc), generate the recently-identified
WMAP haze and corresponding Fermi haze/bubbles. Our modelling bounds the
average magnetic field amplitude in the inner few degrees of the Galaxy to the
range 60 < B/microG < 400 (at 2 sigma confidence) and shows that even TeV CRs
likely do not have time to penetrate into the cores of the region's dense
molecular clouds before the wind removes them from the region. This latter
finding apparently disfavours scenarios in which CRs - in this star-burst-like
environment - act to substantially modify the conditions of star-formation. We
speculate that the wind we identify plays a crucial role in advecting
low-energy positrons from the Galactic nucleus into the bulge, thereby
explaining the extended morphology of the 511 keV line emission. (abridged)Comment: One figure corrected. Accepted for publication in MNRAS. 29 pages, 14
figure
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