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Structure and stress of Re(11%21); chiral terraces at a racemic surface
The surface structure and morphology of the clean Re(11%21) surface has been investigated through combined low energy electron diffraction intensity analysis of data taken at multiple angles of incidence, scanning tunneling microscopy, and first-principles density functional calculations. The results show how this globally racemic surface terminates in two chirally distinct terraces, which show largescale out-of-plane atomic relaxations and in-plane lateral movement of the uppermost atoms. We further identify and discuss the initial stages of step bunching upon adsorption of oxygen that leads ultimately to the large-scale faceting of the surface. Finally, we present calculations of surface stress and the response to applied surface strain, which suggest routes to the exertion of control over the expression of chirality at the surface
A Specially Constructed Metallograph for Use at Elevated Temperatures
A Metallographic microscope was developed with provision for heating a specimen to 1800 F in protective atmospheres, that is, vacuum or gas. A special objective was constructed of reflecting elements with an unusually long working distance (7/16 in.) and a high numerical aperture (0.5). Changes in specimen microstructure were observed and recorded on 35-millimeter motion-picture film. The resulting pictures were projected as motion pictures and individual frames were cut and enlargements made for close observation. Structural changes upon heating a 0.35-percent annealed carbon steel and a 5-percent tin phosphor bronze specimen were observed and recorded. Newly formed microstructure were revealed by selective vacuum etching and specimen relief resulting from recrystallization and varying grain orientation
Biliary Duct Granular Cell Tumor: A Rare But Surgically Curable Benign Tumor
Granulosa cell tumors are rare benign tumors which may be found throughout the body. Rare cases are
isolated within the biliary tree. If completely resected, surgical excision is curative
High Temperature Superconducting Magnets with Active Control for Attraction Levitation Transport Applications
A research program, involving 3 British universities, directed at quantifying the controllability of High Temperature Superconducting (HTS) magnets for use in attraction levitation transport systems will be described. The work includes measurement of loss mechanisms for iron cored HTS magnets which need to produce a flux density of approx. 1 tesla in the airgap between the magnet poles and a ferromagnetic rail. This flux density needs to be maintained and this is done by introducing small variations of the magnet current using a feedback loop, at frequencies up to 10 Hz to compensate for load changes, track variation etc. The test magnet assemblies constructed so far will be described and the studies and modelling of designs for a practical levitation demonstrator (using commercially obtained HTS tape) will be discussed with particular emphasis on how the field distribution and its components, e.g., the component vector normal to the broad face of the tape, can radically affect design philosophy compared to the classical electrical engineering approach. Although specifically aimed at levitation transport the controllability data obtained have implications for a much wider range of applications
Does clinical management improve outcomes following self-Harm? Results from the multicentre study of self-harm in England
Background
Evidence to guide clinical management of self-harm is sparse, trials have recruited selected samples, and psychological treatments that are suggested in guidelines may not be available in routine practice.
Aims
To examine how the management that patients receive in hospital relates to subsequent outcome.
Methods
We identified episodes of self-harm presenting to three UK centres (Derby, Manchester, Oxford) over a 10 year period (2000 to 2009). We used established data collection systems to investigate the relationship between four aspects of management (psychosocial assessment, medical admission, psychiatric admission, referral for specialist mental health follow up) and repetition of self-harm within 12 months, adjusted for differences in baseline demographic and clinical characteristics.
Results
35,938 individuals presented with self-harm during the study period. In two of the three centres, receiving a psychosocial assessment was associated with a 40% lower risk of repetition, Hazard Ratios (95% CIs): Centre A 0.99 (0.90–1.09); Centre B 0.59 (0.48–0.74); Centre C 0.59 (0.52–0.68). There was little indication that the apparent protective effects were mediated through referral and follow up arrangements. The association between psychosocial assessment and a reduced risk of repetition appeared to be least evident in those from the most deprived areas.
Conclusion
These findings add to the growing body of evidence that thorough assessment is central to the management of self-harm, but further work is needed to elucidate the possible mechanisms and explore the effects in different clinical subgroups
Modeling regional-scale wildland fire emissions with the wildland fire emissions information system
As carbon modeling tools become more comprehensive, spatial data are needed to improve quantitative maps of carbon emissions from fire. The Wildland Fire Emissions Information System (WFEIS) provides mapped estimates of carbon emissions from historical forest fires in the United States through a web browser. WFEIS improves access to data and provides a consistent approach to estimating emissions at landscape, regional, and continental scales. The system taps into data and tools developed by the U.S. Forest Service to describe fuels, fuel loadings, and fuel consumption and merges information from the U.S. Geological Survey (USGS) and National Aeronautics and Space Administration on fire location and timing. Currently, WFEIS provides web access to Moderate Resolution Imaging Spectroradiometer (MODIS) burned area for North America and U.S. fire-perimeter maps from the Monitoring Trends in Burn Severity products from the USGS, overlays them on 1-km fuel maps for the United States, and calculates fuel consumption and emissions with an open-source version of the Consume model. Mapped fuel moisture is derived from daily meteorological data from remote automated weather stations. In addition to tabular output results, WFEIS produces multiple vector and raster formats. This paper provides an overview of the WFEIS system, including the web-based system functionality and datasets used for emissions estimates. WFEIS operates on the web and is built using open-source software components that work with open international standards such as keyhole markup language (KML). Examples of emissions outputs from WFEIS are presented showing that the system provides results that vary widely across the many ecosystems of North America and are consistent with previous emissions modeling estimates and products
Spatial Variability in the Ratio of Interstellar Atomic Deuterium to Hydrogen. II. Observations toward Gamma2 Velorum and Zeta Puppis by the Interstellar Medium Absorption Profile Spectrograph
To measure interstellar atomic deuterium abundances, we used the Interstellar
Medium Absorption Profile Spectrograph (IMAPS) to obtain spectra of gamma2 Vel
and zeta Pup over the wavelength interval 930-1150 A at a resolving power of
80,000. The interstellar D I features are resolved and cleanly separated from
interstellar H I in the Ly-delta and Ly-epsilon profiles of both sight lines,
and also in the Ly-gamma profile of zeta Pup. The D I profiles were modeled
using a velocity template derived from several N I lines in the IMAPS spectra
recorded at higher S/N. To find the best D I column density, we minimized
chi-squares for model D I profiles that included not only the N(D I) as a free
parameter, but also the effects of several potential sources of systematic
error which could also be varied. For both stars, H I column densities were
measured by analyzing Ly-alpha absorption profiles in a large number of IUE
high dispersion spectra. Ultimately we found that D/H = 2.18(+0.36,-0.31)e-5
for gamma2 Vel and 1.42(+0.25,-0.23)e-5 for zeta Pup, values that contrast
markedly with D/H derived in Paper I for delta Ori (the stated errors are 90%
confidence limits). Evidently, the atomic D/H ratio in the ISM, averaged over
path lengths of 250 to 500 pc, exhibits significant spatial variability.
Furthermore, variations in D/H do not appear to be anticorrelated with N/H.
Within the framework of standard Big Bang Nucleosynthesis, the large value of
D/H found toward gamma2 Vel is equivalent to a cosmic baryon density of Omega_B
h^2 = 0.023 (+-0.002), which we regard as an upper limit since there is no
correction for the destruction of deuterium in stars.Comment: 37 pages, 10 figures, to appear in the Astrophysical Journa
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