1,934 research outputs found
Velocity Dependence of the Differential Cross Sections for the Scattering of Atomic Beams of K and Cs by Hg
Measurements of the velocity dependence of the angular intensity distribution of potassium and cesium beams scattered by a crossed beam of mercury are presented. The alkali beam was velocity selected, with a triangular velocity distribution (halfâintensity width 4.7% of peak velocity); the velocity was varied over the range 185â1000 m/sec. The Hg beam had a thermal distribution; the average Hg speed was âŒ235 meters per second. The scattering data have been converted to the centerâofâmass system. The angular distributions show the expected strong forward scattering and evidence the phenomenon of rainbow scattering. The energy dependence of the rainbow angle is used to evaluate the interatomic potential well depth, interpreted as the dissociation energy De of the 2ÎŁ+ molecular ground state. Values (in ergĂ1014) thus obtained (±5%) are 7.46 for KHg and 7.72 for CsHg. Absolute values of differential cross sections could not be obtained; only relative cross sections D(Ξ) are reported. The observed lowâangle behavior D(Ξ) âΞâ 7/3 serves as direct experimental confirmation of the râ6 dependence of the longârange attractive potential for KâHg and CsâHg systems.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/69910/2/JCPSA6-37-9-2019-1.pd
C13 and Deuterium Isotope Effects in the Photolysis of Methyl and Ethyl Bromide
Relative rates of formation of isotopic radicals in the photolysis of gaseous methyl and ethyl bromide have been measured. Photolyses (2537 A) were carried out in a large excess of cyclopentane. Methyl (or ethyl) radicals formed in the primary CâBr bond scission abstract H from cyclopentane to form methane (or ethane). For methyl bromide, the C12/C13 enrichment factor for the first fraction of the methane was 1.039±0.003. The corresponding factor for the αâcarbonâBr rupture in ethyl bromide was 1.041±0.004. In the deuterium experiments, CH3BrâCD3Br mixtures in excess cyclopentane were photolyzed. The H/D fractionation factor (based on CH4/CD3H) was 1.41±0.01.The difference in rates of formation of isotopic radicals is due to the difference in ultraviolet absorption coefficients of the isotopic alkyl bromides. At 2537 A the observed ratio of the extinction coefficient of CH3Br relative to that of CD3Br is 1.38±0.05.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/71079/2/JCPSA6-30-4-973-1.pd
Development of a tailored, telehealth intervention to address chronic pain and heavy drinking among people with HIV infection: integrating perspectives of patients in HIV care.
BACKGROUND:
Chronic pain and heavy drinking commonly co-occur and can infuence the course of HIV. There have been no interventions designed to address both of these conditions among people living with HIV (PLWH), and none that have used telehealth methods. The purpose of this study was to better understand pain symptoms, patterns of alcohol use, treatment experiences, and technology use among PLWH in order to tailor a telehealth intervention that addresses these conditions
SUBJECTS:
Ten participants with moderate or greater chronic pain and heavy drinking were recruited from a cohort of patients engaged in HIV-care (Boston Alcohol Research Collaborative on HIV/AIDS Cohort) and from an integrated HIV/primary care clinic at a large urban hospital.
METHODS:
One-on-one interviews were conducted with participants to understand experiences and treatment
of HIV, chronic pain, and alcohol use. Participantsâ perceptions of the infuence of alcohol on HIV and chronic pain were explored as was motivation to change drinking. Technology use and treatment preferences were examined in the fnal section of the interview. Interviews were recorded, transcribed and uploaded into NVivoÂź v12 software for analysis. A codebook was developed based on interviews followed by thematic analysis in which specifc meanings were assigned to codes.
RESULTS:
A number of themes were identifed that had implications for intervention tailoring including: resilience
in coping with HIV; autonomy in health care decision-making; coping with pain, stress, and emotion; understanding treatment rationale; depression and social withdrawal; motives to drink and refrain from drinking; technology use and capacity; and preference for intervention structure and style. Ratings of intervention components indicated that participants viewed each of the proposed intervention content areas as âhelpfulâ to âvery helpfulâ. Videoconferencing was viewed as an acceptable modality for intervention delivery
CONCLUSIONS:
Results helped specify treatment targets and provided information about how to enhance intervention
delivery. The interviews supported the view that videoconferencing is an acceptable telehealth method of addressing chronic pain and heavy drinking among PLWH.UH2 AA026192 - NIAAA NIH HHSPublished versio
SEPARATION OF EPIDERMAL LAYERS OF THE NEWBORN RAT
A method is presented for the separation of epidermal strata by the successive elimination of either the basal or basal and spinous cells with 0.24 M NH4Cl at pH 9.5. Histologic evidence suggests that the residual epidermal strata obtained after incubation of the skin with NH4Cl are reproducible; hence, this technique circumvents loss of granular layer histidine-rich protein inherent with trypsin separation and provides an effective procedure for biochemical analysis of arginine-rich and lysine-rich proteins in the various differentiating epidermal cells
SNANA: A Public Software Package for Supernova Analysis
We describe a general analysis package for supernova (SN) light curves,
called SNANA, that contains a simulation, light curve fitter, and cosmology
fitter. The software is designed with the primary goal of using SNe Ia as
distance indicators for the determination of cosmological parameters, but it
can also be used to study efficiencies for analyses of SN rates, estimate
contamination from non-Ia SNe, and optimize future surveys. Several SN models
are available within the same software architecture, allowing technical
features such as K-corrections to be consistently used among multiple models,
and thus making it easier to make detailed comparisons between models. New and
improved light-curve models can be easily added. The software works with
arbitrary surveys and telescopes and has already been used by several
collaborations, leading to more robust and easy-to-use code. This software is
not intended as a final product release, but rather it is designed to undergo
continual improvements from the community as more is learned about SNe. Below
we give an overview of the SNANA capabilities, as well as some of its
limitations. Interested users can find software downloads and more detailed
information from the manuals at http://www.sdss.org/supernova/SNANA.html .Comment: Accepted for publication in PAS
Embedding initial data for black hole collisions
We discuss isometric embedding diagrams for the visualization of initial data
for the problem of the head-on collision of two black holes. The problem of
constructing the embedding diagrams is explicitly presented for the best
studied initial data, the Misner geometry. We present a partial solution of the
embedding diagrams and discuss issues related to completing the solution.Comment: (27pp text, 11 figures
Residue currents associated with weakly holomorphic functions
We construct Coleff-Herrera products and Bochner-Martinelli type residue
currents associated with a tuple of weakly holomorphic functions, and show
that these currents satisfy basic properties from the (strongly) holomorphic
case, as the transformation law, the Poincar\'e-Lelong formula and the
equivalence of the Coleff-Herrera product and the Bochner-Martinelli type
residue current associated with when defines a complete intersection.Comment: 28 pages. Updated with some corrections from the revision process. In
particular, corrected and clarified some things in Section 5 and 6 regarding
products of weakly holomorphic functions and currents, and the definition of
the Bochner-Martinelli type current
- âŠ