3,553 research outputs found

    Thermal infrared spectroscopy of Europa and Callisto

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    The trailing hemispheres of Europa and Callisto were observed at 9–13 μm, and a spectrum of Europa with better spectral resolution and a better signal-to-noise ratio than was previously possible has been derived. The ratio spectrum of the two satellites has a signal-to-noise ratio of approximately 30 for a spectral resolving power of approximately 50. The disk-integrated, effective color temperature ratio for the two satellites is consistent with broadband, thermal infrared photometry from previous ground-based studies and from the Galileo photopolarimeter radiometer. The ratio spectrum was combined with the average Voyager 1 spectrum of Callisto to obtain a 9–13 μm spectrum of Europa with a signal-to-noise ratio that is a factor of 10 better than that in the average Voyager spectrum of Europa. After convolving the measured spectrum to the expected width of water ice emissivity features, ∼1 μm, no spectral features that could be attributed to water ice on the surface of Europa are apparent at the 0.6–0.7% level. The absence of spectral features attributable to water ice is consistent with the proposal that the equatorial region of Europa that was observed may be composed primarily of a heavily hydrated mineral. The absence of water ice features may also be the result of a large fractional abundance of fine particles, such as that found on the surface of the Moon

    Knowledge of Federal Regulations for Mental Health Research Involving Prisoners

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    BACKGROUND: Given their vulnerability to coercion and exploitation, prisoners who participate in research are protected by Office for Human Research Protections (OHRP) regulations designed to ensure their safety and wellbeing. Knowledge of these regulations is essential for researchers who conduct and institutional review boards (IRBs) that oversee mental healthresearch in correctional settings. METHODS: We explored depth of knowledge of OHRP regulations by surveying a nationwide sample of: (1) mental health researchers who have conducted research in correctional settings; (2) mental health researchers who have conducted research in non-correctional settings; (3) IRB members who have overseen mental health research in correctional settings; (4) IRB members who have overseen mental health research in in non-correctional settings; and (5) IRB prisoner representatives. Participants responded to a 10-item knowledge questionnaire based on OHRP regulations. RESULTS: 1,256 participants provided usable data (44.9% response rate). Results revealed limited knowledge of OHRP regulations, with a mean across groups of 44.1% correct answers. IRB Prisoner representatives, IRB members, and researchers with correctional experience demonstrated the highest levels of knowledge; however, even these participants were able to correctly answer only approximately 50% of the items. CONCLUSIONS: Although awareness that prisoners are a protected population and that different regulatory procedures apply to research with them is likely to be universal among researchers and IRB members, our findings reveal limited mastery of the specific OHRP regulations that are essential knowledge for researchers who conduct and IRB members who oversee mental health research in correctional settings. Given well-documented health and healthcare disparities, prisoners could potentially benefit greatly from mental health research; increasing knowledge of the OHRP regulations among researchers and IRB members is a crucial step toward meeting this important public health goal

    Atmospheric oxidation chemistry and ozone production: Results from SHARP 2009 in Houston, Texas

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    This study considers whether spikes in nitrate in snow sampled at Summit, Greenland, from August 2000 to August 2002 are related to solar proton events. After identifying tropospheric sources of nitrate on the basis of correlations with sulfate, ammonium, sodium, and calcium, we use the three-dimensional global Whole Atmosphere Community Climate Model (WACCM) to examine unaccounted for nitrate spikes. Model calculations confirm that solar proton events significantly impact HOx, NOx, and O3 levels in the mesosphere and stratosphere during the weeks and months following the major 9 November 2000 solar proton event. However, solar proton event (SPE)-enhanced NOy calculated within the atmospheric column is too small to account for the observed nitrate peaks in surface snow. Instead, our WACCM results suggest that nitrate spikes not readily accounted for by measurement correlations are likely of anthropogenic origin. These results, consistent with other recent studies, imply that nitrate spikes in ice cores are not suitable proxies for individual SPEs and motivate the need to identify alternative proxies

    Nitrate deposition to surface snow at Summit, Greenland, following the 9 November 2000 solar proton event

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    Abstract This study considers whether spikes in nitrate in snow sampled at Summit, Greenland, from August 2000 to August 2002 are related to solar proton events. After identifying tropospheric sources of nitrate on the basis of correlations with sulfate, ammonium, sodium, and calcium, we use the three-dimensional global Whole Atmosphere Community Climate Model (WACCM) to examine unaccounted for nitrate spikes. Model calculations confirm that solar proton events significantly impact HOx, NOx, and O3 levels in the mesosphere and stratosphere during the weeks and months following the major 9 November 2000 solar proton event. However, solar proton event (SPE)-enhanced NOy calculated within the atmospheric column is too small to account for the observed nitrate peaks in surface snow. Instead, our WACCM results suggest that nitrate spikes not readily accounted for by measurement correlations are likely of anthropogenic origin. These results, consistent with other recent studies, imply that nitrate spikes in ice cores are not suitable proxies for individual SPEs and motivate the need to identify alternative proxies. Key Points A global model simulates nitrate deposition from solar proton events Soluble ion correlations in Summit snow identify tropospheric sources of nitrate Nitrate ions in snow are found not to be a good proxy for solar proton events

    Psychiatric Symptomatology among Individuals in Alcohol Detoxification Treatment

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    The coexistence of psychiatric symptomatology among individuals receiving longer-term treatment for alcohol use disorders has been well-established; however, less is known about comorbidity among individuals receiving alcohol detoxification. Using the Brief Symptom Inventory (BSI; Derogatis, 1992), we compared psychiatric symptomatology among 815 individuals receiving short-term detoxification services with normative data from nonpatients, psychiatric patients, and out-of-treatment individuals using street drugs. Findings revealed that individuals in the current sample reported a wide range of psychiatric symptoms with over 80% meeting BSI criteria for diagnosable mental illness. These BSI scores were significantly more severe than those reported by out-of-treatment individuals using street drugs and most closely resembled BSI scores reported for adult psychiatric inpatients. Findings suggest that routine screening for severe mental health symptoms appears warranted in detoxification units. Such screening would greatly increase the chance that coexistence of substance use and other psychiatric disorders would be properly addressed in ongoing treatment

    Encyclopedia of Case Study Research

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    Michael Pagano is a contributing author Healthcare Practice Guidelines and Case Studies . Book description: The Encyclopedia of Case Study Research provides a compendium on the important methodological issues in conducting case study research and explores both the strengths and weaknesses of different paradigmatic approaches. These two volumes focus on the distinctive characteristics of case study research and its place within and alongside other research methodologies.https://digitalcommons.fairfield.edu/communications-books/1008/thumbnail.jp

    Measuring the Relative Phase of the Energy Gap in a High-Temperature Superconductor with EELS

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    A method of measuring the relative phase of the energy gap in a high-temperature superconductor is suggested for electron energy loss spectroscopy. Energy-resolved measurements of off-specular scattering should show a feature similar to the specular feature associated with the gap. Unlike the specular feature, which reflects an average of the gap over the (normal) Fermi surface, the energy loss of the off-specular feature depends on the superconducting energy gap at only two locations on the Fermi surface. The onset of the feature reflects the relative phase between these two points. This result is independent of surface characteristics. Such characteristics affect the {\it magnitude} of the off-specular feature, not its location or onset. The size of the feature is estimated for a simple surface model. Implications of specific measurements on Bi2Sr2CaCu2O8\rm Bi_2Sr_2CaCu_2O_8 are discussed

    Thermal degradation of new and aged urethane foam and epon 826 epoxy.

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    Thermal desorption spectroscopy was used to monitor the decomposition as a function of temperature for the foam and epoxy as a function of temperature in the range of 60C to 170C. Samples were studied with one day holds at each of the studied temperatures. Both new (FoamN and EpoxyN) and aged (FoamP and EpoxyP) samples were studied. During these ~10 day experiments, the foam samples lost 11 to 13% of their weight and the EpoxyN lost 10% of its weight. The amount of weight lost was difficult to quantify for EpoxyP because of its inert filler. The onset of the appearance of organic degradation products from FoamP began at 110C. Similar products did not appear until 120C for FoamN, suggesting some effect of the previous decades of storage for FoamP. In the case of the epoxies, the corresponding temperatures were 120C for EpoxyP and 110C for EpoxyN. Suggestions for why the aged epoxy seems more stable than newer sample include the possibility of incomplete curing or differences in composition. Recommendation to limit use temperature to 90-100C for both epoxy and foam
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