5,154 research outputs found
Effective Hamiltonian Approach to Hyperon Beta Decay with Final-State Baryon Polarization
Using an effective Hamiltonian approach, we obtain expressions for hyperon
beta decay final-state baryon polarization. Terms through second order in the
energy release are retained. The resulting approximate expressions are much
simpler and more compact than the exact expressions, and they agree closely
with them.Comment: 1 Figure Will appear in Phys Rev D 60 Article 117505 (Dec 1, 1999
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Capacity planning in a transitional economy: What issues? Which models?
This paper is devoted to an exploration of the important issues facing the Russian power generation system and its evolution in the foreseeable future and the kinds of modeling approaches that capture those issues. These issues include, for example, (1) trade-offs between investments in upgrading and refurbishment of existing thermal (fossil-fired) capacity and safety enhancements in existing nuclear capacity versus investment in new capacity, (2) trade-offs between investment in completing unfinished (under construction) projects based on their original design versus investment in new capacity with improved design, (3) incorporation of demand-side management options (investments in enhancing end-use efficiency, for example) within the planning framework, (4) consideration of the spatial dimensions of system planning including investments in upgrading electric transmission networks or fuel shipment networks and incorporating hydroelectric generation, (5) incorporation of environmental constraints and (6) assessment of uncertainty and evaluation of downside risk. Models for exploring these issues include low power shutdown (LPS) which are computationally very efficient, though approximate, and can be used to perform extensive sensitivity analyses to more complex models which can provide more detailed answers but are computationally cumbersome and can only deal with limited issues. The paper discusses which models can usefully treat a wide range of issues within the priorities facing decision makers in the Russian power sector and integrate the results with investment decisions in the wider economy
Total column CO_2 measurements at Darwin, Australia – site description and calibration against in situ aircraft profiles
An automated Fourier Transform Spectroscopic (FTS) solar observatory was established in Darwin, Australia in August 2005. The laboratory is part of the Total Carbon Column Observing Network, and measures atmospheric column abundances of CO_2 and O_2 and other gases. Measured CO_2 columns were calibrated against integrated aircraft profiles obtained during the TWP-ICE campaign in January–February 2006, and show good agreement with calibrations for a similar instrument in Park Falls, Wisconsin. A clear-sky low airmass relative precision of 0.1% is demonstrated in the CO2 and O2 retrieved column-averaged volume mixing ratios. The 1% negative bias in the FTS X_(CO_2) relative to the World Meteorological Organization (WMO) calibrated in situ scale is within the uncertainties of the NIR spectroscopy and analysis
NOAA Coastal Change Analysis Program (C-CAP): Guidance for Regional Implementation
EXECUTIVE SUMMARY:
The Coastal Change Analysis Programl (C-CAP) is developing
a nationally standardized database on landcover and habitat change in the coastal regions of the United States. C-CAP is part of the Estuarine Habitat Program (EHP) of NOAA's Coastal Ocean Program (COP). C-CAP inventories coastal submersed habitats, wetland habitats, and adjacent uplands and monitors changes in these habitats on a one- to five-year cycle. This type of information and frequency of detection are required to improve scientific understanding of the linkages of coastal and submersed wetland habitats with adjacent uplands and with the distribution, abundance,
and health of living marine resources. The monitoring
cycle will vary according to the rate and magnitude of
change in each geographic region. Satellite imagery
(primarily Landsat Thematic Mapper), aerial photography,
and field data are interpreted, classified, analyzed,
and integrated with other digital data in a geographic
information system (GIS). The resulting landcover
change databases are disseminated in digital form
for use by anyone wishing to conduct geographic analysis
in the completed regions. C-CAP spatial information on coastal change will be input to EHP conceptual and predictive models to support coastal resource policy planning and analysis. CCAP products will include 1) spatially registered digital databases and images, 2) tabular summaries by state, county, and hydrologic unit, and 3) documentation. Aggregations to larger areas (representing habitats, wildlife refuges, or management districts) will be provided on a case-by-case basis. Ongoing C-CAP research will continue to explore techniques for remote determination of biomass, productivity, and functional status of wetlands and will evaluate new technologies (e.g. remote sensor systems, global positioning systems, image processing algorithms) as they become available. Selected hardcopy land-cover change maps will be produced at local (1:24,000) to regional scales (1:500,000) for distribution. Digital land-cover change data will be provided to users for the cost of reproduction.
Much of the guidance contained in this document was developed through a series of professional workshops
and interagency meetings that focused on a) coastal wetlands and uplands; b) coastal submersed habitat including aquatic beds; c) user needs; d) regional
issues; e) classification schemes; f) change detection
techniques; and g) data quality. Invited participants
included technical and regional experts and representatives
of key State and Federal organizations. Coastal habitat managers and researchers were given an opportunity for review and comment. This document summarizes C-CAP protocols and procedures that are to be used by scientists throughout the United States to develop consistent and reliable coastal change information for input to the C-CAP nationwide database. It also provides useful guidelines for contributors working on related projects. It is considered a working document subject to periodic review and revision.(PDF file contains 104 pages.
Identification of pathogen genomic variants through an integrated pipeline
Background: Whole-genome sequencing represents a powerful experimental tool for pathogen research. We present methods for the analysis of small eukaryotic genomes, including a streamlined system (called Platypus) for finding single nucleotide and copy number variants as well as recombination events. Results: We have validated our pipeline using four sets of Plasmodium falciparum drug resistant data containing 26 clones from 3D7 and Dd2 background strains, identifying an average of 11 single nucleotide variants per clone. We also identify 8 copy number variants with contributions to resistance, and report for the first time that all analyzed amplification events are in tandem. Conclusions: The Platypus pipeline provides malaria researchers with a powerful tool to analyze short read sequencing data. It provides an accurate way to detect SNVs using known software packages, and a novel methodology for detection of CNVs, though it does not currently support detection of small indels. We have validated that the pipeline detects known SNVs in a variety of samples while filtering out spurious data. We bundle the methods into a freely available package
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The working alliance in stuttering treatment: a neglected variable?
Background
Multiple factors can influence the working alliance and treatment outcome in speech and language therapy. The ‘working alliance’ is an important concept in treatment and can be described as the degree to which a treatment dyad is engaged in collaborative, purposive work. To date, relatively little attention has been paid to this concept within speech and language treatment in general, and within stuttering treatment research in particular.
Aims
To investigate the role of the working alliance within stuttering treatment, and to evaluate whether the quality of the working alliance correlated with clients’ concept of motivation and treatment outcomes 6 months post‐therapy.
Methods & Procedures
Eighteen adults (21‐61 years) participated in this multiple single‐case treatment study, with treatment facilitated by an experienced speech and language therapist. The working alliance was investigated using the Working Alliance Inventory—Short Version Revised (WAI‐SR), an Extended version of the Client Preferences for Stuttering Treatment (CPST‐E), the Overall Assessment of Speakers’ Experience of Stuttering—Adult version (OASES‐A), the Wright & Ayre Stuttering Self‐Rating Profile (WASSP) and the Hospital Anxiety and Depression Scale (HADS).
Outcomes & Results
Analyses demonstrated significant associations between the working alliance and client motivation (r = 0.781) and treatment outcomes (r = 0.644) 6 months post‐treatment. The association between client‐led goals and therapy tasks appeared particularly important.
Conclusions & Implications
The working alliance between speech and language therapists and persons who stutter matters. Within the alliance, the level of client–clinician agreement on treatment goals and therapy tasks may be of greater importance than the bond between client and clinician. Further research with greater numbers of participants is warranted
Cascade and anti-Cascade Polarization Measurements at 800 GeV/c
The polarization of neutral Cascade and anti-Cascade hyperons produced by 800
GeV/c protons on a BeO target at a fixed targeting angle of 4.8 mrad is
measured by the KTeV experiment at Fermilab. Our result of 9.7% for the neutral
Cascade polarization shows no significant energy dependence when compared to a
result obtained at 400 GeV/c production energy and at twice our targeting
angle. The polarization of the neutral anti-Cascade is measured for the first
time and found to be consistent with zero. We also examine the dependence of
polarization on transverse production momentum.Comment: 4 page PR
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