8,899 research outputs found
The effect of flight line spacing on radioactivity inventory and spatial feature characteristics of airborne gamma-ray spectrometry data
Airborne Gamma Spectrometry (AGS) is well suited to the mapping of radioactivity in the environment. Flight parameters (e.g. speed and line spacing) directly affect the rate of area coverage, cost, and data quality of any survey. The influences of line spacing have been investigated for data from interâtidal, coastal and upland environments with a range of <sup>137</sup>Cs activity concentrations and depositional histories. Estimates of the integrated <sup>137</sup>Cs activity (âinventoryâ) within specified areas and the shapes of depositional features were calculated for subsets of the data at different line spacings. Features with dimensions greater than the line spacing show variations in inventory and area of less than 3%, and features with dimensions less than the line spacing show larger variations and a decreased probability of detection. The choice of line spacing for a task is dependent on the dimensions of the features of interest and required edge definition. Options for line spacing for different tasks are suggested. It is noted that for regional mapping, even 5â10 km line spacing can produce useful data
Experiences of diagnosis, stigma, culpability, and disclosure in male patients with hepatitis C virus: an interpretative phenomenological analysis
The current study aimed to explore the lived experience of patients with hepatitis C virus infection. Semi-structured interviews were conducted with seven male participants living with hepatitis C virus and were analysed using interpretative phenomenological analysis. Two master themes were identified: (1) diagnosis and the search for meaning and (2) impact of stigma on disclosure. Participants reported fears of contaminating others, feelings of stigma and concerns of disclosing the condition to others. Response to diagnosis, stigma and disclosure among the participants appeared to be interrelated and directly related to locus of blame for virus contraction. More specifically, hepatitis C virus transmission via medical routes led to an externalisation of culpability and an openness to disclosure. Transmission of hepatitis C virus as a direct result of intravenous drug use led to internalised blame and a fear of disclosure. The inter- and intra-personal consequences of hepatitis C virus explored in the current study have potential implications for tailoring future psychological therapy and psychoeducation to the specific needs of the hepatitis C virus population
A Common Eider Ă King Eider Hybrid Captured on the Kent Peninsula, Nunavut
On 25 June 2002, we captured and recorded measurements of a male common eider (Somateria mollissima) Ă king eider (S. spectabilis) hybrid at Nauyak Lake, on the Kent Peninsula, Nunavut. This is the first documented capture of a hybrid eider, rarely observed in North America. Structural body measurements and mass of the hybrid were intermediate compared to those of Pacific common eiders (S. m. v-nigrum) at the same study site and king eiders at a nearby study site during the same time of year. The plumage of the captured hybrid had characteristics of both parent species. Mate pairing on overlapping spring staging or wintering areas of common and king eiders may occasionally result in hybrid offspring.Le 25 juin 2002, nous avons capturĂ© un hybride composĂ© dâun eider Ă duvet (Somateria mollissima) Ă un eider Ă tĂȘte grise (S. spectabilis) au lac Nauyak, dans la pĂ©ninsule de Kent, au Nunavut, puis nous avons pris note de ses mesures. Il sâagit de la premiĂšre capture rĂ©pertoriĂ©e dâun eider hybride, ce qui est rarement observĂ© en AmĂ©rique du Nord. Les mesures et la masse de la structure corporelle de lâhybride Ă©taient intermĂ©diaires comparativement Ă celles des eiders Ă duvet du Pacifique (S. m. v-nigrum) du mĂȘme lieu dâĂ©tude et Ă celles des eiders Ă tĂȘte grise dâun lieu dâĂ©tude avoisinant pendant la mĂȘme pĂ©riode de lâannĂ©e. Le plumage de lâhybride que nous avons capturĂ© prĂ©sentait des caractĂ©ristiques des deux espĂšces. Il arrive parfois que les accouplements aux haltes migratoires du printemps ou aux aires dâhivernage partagĂ©es par les eiders Ă duvet et les eiders Ă tĂȘte grise donnent lieu Ă une progĂ©niture hybride
Arterial pathology in canine mucopolysaccharidosis-I and response to therapy.
Mucopolysaccharidosis-I (MPS-I) is an inherited deficiency of α-L-iduronidase (IdU) that causes lysosomal accumulation of glycosaminoglycans (GAG) in a variety of parenchymal cell types and connective tissues. The fundamental link between genetic mutation and tissue GAG accumulation is clear, but relatively little attention has been given to the morphology or pathogenesis of associated lesions, particularly those affecting the vascular system. The terminal parietal branches of the abdominal aorta were examined from a colony of dogs homozygous (MPS-I affected) or heterozygous (unaffected carrier) for an IdU mutation that eliminated all enzyme activity, and in affected animals treated with human recombinant IdU. High-resolution computed tomography showed that vascular wall thickenings occurred in affected animals near branch points, and associated with low endothelial shear stress. Histologically these asymmetric 'plaques' entailed extensive intimal thickening with disruption of the internal elastic lamina, occluding more than 50% of the vascular lumen in some cases. Immunohistochemistry was used to show that areas of sclerosis contained foamy (GAG laden) macrophages, fibroblasts and smooth muscle cells, with loss of overlying endothelial basement membrane and claudin-5 expression. Lesions contained scattered cells expressing nuclear factor-ÎșÎČ (p65), increased fibronectin and transforming growth factor ÎČ-1 signaling (with nuclear Smad3 accumulation) in comparison to unaffected vessels. Intimal lesion development and morphology was improved by intravenous recombinant enzyme treatment, particularly with immune tolerance to this exogenous protein. The progressive sclerotic vasculopathy of MPS-I shares some morphological and molecular similarities to atherosclerosis, including formation in areas of low shear stress near branch points, and can be reduced or inhibited by intravenous administration of recombinant IdU
The Jet of 3C 17 and the Use of Jet Curvature as a Diagnostic of the X-ray Emission Process
We report on the X-ray emission from the radio jet of 3C 17 from Chandra
observations and compare the X-ray emission with radio maps from the VLA
archive and with the optical-IR archival images from the Hubble Space
Telescope. X-ray detections of two knots in the 3C 17 jet are found and both of
these features have optical counterparts. We derive the spectral energy
distribution for the knots in the jet and give source parameters required for
the various X-ray emission models, finding that both IC/CMB and synchrotron are
viable to explain the high energy emission. A curious optical feature (with no
radio or X-ray counterparts) possibly associated with the 3C 17 jet is
described. We also discuss the use of curved jets for the problem of
identifying inverse Compton X-ray emission via scattering on CMB photons.Comment: 6 pages, 6 figure (3 in color), 4 tables, ApJ accepte
Elliptic Solitons and Groebner Bases
We consider the solution of spectral problems with elliptic coefficients in
the framework of the Hermite ansatz. We show that the search for exactly
solvable potentials and their spectral characteristics is reduced to a system
of polynomial equations solvable by the Gr\"obner bases method and others. New
integrable potentials and corresponding solutions of the Sawada-Kotera,
Kaup-Kupershmidt, Boussinesq equations and others are found.Comment: 18 pages, no figures, LaTeX'2
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