1,017 research outputs found

    Testing a simple recipe for estimating galaxy masses from minimal observational data

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    The accuracy and robustness of a simple method to estimate the total mass profile of a galaxy is tested using a sample of 65 cosmological zoom-simulations of individual galaxies. The method only requires information on the optical surface brightness and the projected velocity dispersion profiles and therefore can be applied even in case of poor observational data. In the simulated sample massive galaxies (σ≃200−400\sigma \simeq 200-400 \kms) at redshift z=0z=0 have almost isothermal rotation curves for broad range of radii (RMS ≃5\simeq 5% for the circular speed deviations from a constant value over 0.5Reff<r<3Reff0.5R_{\rm eff} < r < 3R_{\rm eff}). For such galaxies the method recovers the unbiased value of the circular speed. The sample averaged deviation from the true circular speed is less than ∼1\sim 1% with the scatter of ≃5−8\simeq 5-8% (RMS) up to R≃5ReffR \simeq 5R_{\rm eff}. Circular speed estimates of massive non-rotating simulated galaxies at higher redshifts (z=1z=1 and z=2z=2) are also almost unbiased and with the same scatter. For the least massive galaxies in the sample (σ<150\sigma < 150 \kms) at z=0z=0 the RMS deviation is ≃7−9\simeq 7-9% and the mean deviation is biased low by about 1−21-2%. We also derive the circular velocity profile from the hydrostatic equilibrium (HE) equation for hot gas in the simulated galaxies. The accuracy of this estimate is about RMS ≃4−5\simeq 4-5% for massive objects (M>6.5×1012M⊙M > 6.5\times 10^{12} M_\odot) and the HE estimate is biased low by ≃3−4\simeq 3-4%, which can be traced to the presence of gas motions. This implies that the simple mass estimate can be used to determine the mass of observed massive elliptical galaxies to an accuracy of 5−85-8 % and can be very useful for galaxy surveys.Comment: 15 pages, 14 figures, 1 tabl

    A Longitudinal Analysis of the Impact of Child Custody Loss on Drug Use and Crime Among a Sample of African American Mothers

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    This study examines the influence of child custody loss on drug use and crime among a sample of African American mothers. Two types of custody loss are examined: informal custody loss (child living apart from mother but courts not involved), and official loss (child removed from mother’s care by authorities). Methods—Using data from 339 African American women, longitudinal random coefficient models analyzed the effects of each type of custody loss on subsequent drug use and crime. Results—Results indicated that both informal and official custody loss predicted increased drug use, and informal loss predicted increased criminal involvement. Findings demonstrate that child custody loss has negative health implications for African American mothers, potentially reducing their likelihood of regaining or retaining custody of their children. Conclusions—This study highlights the need to integrate drug treatment and other types of assistance into family case plans to improve reunification rates and outcomes among mothers, children, and families. Additionally, the finding that informal loss predicts increased drug use suggests that community-based efforts within the mother’s social network could be implemented to intervene before child welfare system involvement becomes necessary

    Racism and Illicit Drug Use among African American Women: The Protective Effects of Ethnic Identity, Affirmation, and Behavior

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    Though recent evidence indicates that rates of illicit drug use among African American women are now higher than the national average, little is known about the etiology of substance use in this population. In addition, the effects of racism and other cultural factors are understudied and may be unique amongst African American women. This cross-sectional study explores risk and protective factors for drug use among 204 African American women. More specifically, associations between racism experiences and drug use are investigated in the context of potential moderating influences (i.e., psychosocial resources, social safety net variables, and cultural identity and practices). Findings suggest that racism is associated with drug use, but that its effects diminish with age. In addition, results suggest that psychosocial resources, social safety net factors and culturally specific factors like ethnic community membership and engagement in cultural practices afford African American women some protection against the detrimental effects of racism

    African American Female Offender\u27s Use of Alternative and Traditional Health Services After Re-Entry: Examining the Behavioral Model for Vulnerable Populations

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    This is the first known study to use the Gelberg-Andersen Behavioral Model for Vulnerable Populations to predict African American women\u27s use of three types of health services (alternative, hospitalization, and ambulatory) in the 18 months after release from prison. In the multivariate models, the most robust predictors of all three types of service utilization were in the vulnerable theoretical domains. Alternative health services were predicted by ethnic community membership, higher religiosity, and HIV/HCV. Hospitalizations were predicted by the lack of barriers to health care and disability. Ambulatory office visits were predicted by more experiences of gendered racism, a greater number of physical health problems, and HIV/HCV. Findings highlight the importance of cultural factors and HIV/HCV in obtaining both alternative and formal health care during community re-entry. Clinicians and policymakers should consider the salient role that the vulnerable domain plays in offender\u27s accessing health services

    Examining the Associations of Racism, Sexism, and Stressful Life Events on Psychological Distress among African-American Women

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    African-American women may be susceptible to stressful events and adverse health outcomes as a result of their distinct social location at the intersection of gender and race. Here, racism and sexism are examined concurrently using survey data from 204 African-American women residing in a southeastern U.S. urban city. Associations among racism, sexism, and stressful events across social roles and contexts (i.e., social network loss, motherhood and childbirth, employment and finances, personal illness and injury, and victimization) are investigated. Then, the relationships among these stressors on psychological distress are compared, and a moderation model is explored. Findings suggest that racism and sexism are a significant source of stress in the lives of African-American women and are correlated with one another and with other stressful events. Implications for future research and clinical considerations are discussed. (APA PsycInfo Database Record (c) 2016 APA, all rights reserved

    Adaptation of a Standard Extended-Release Naltrexone (XR-NTX) Protocol for Rural Re-Entering Offenders with OUD

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    BACKGROUND: Despite a growing body of empirical support for the effectiveness of extended-release naltrexone (XR-NTX) to reduce opioid relapse among people with opioid use disorder (OUD) transitioning from a correctional facility to the community, continuity of care following release remains challenging. This paper describes a research-based adaptation of a state\u27s standard of care XR-NTX protocol using the ADAPT-ITT framework for delivery in a non-traditional, non-treatment, community criminal justice setting (P&P office), as well as the expansion of services by a local Federally Qualified Health Center (FQHC) provider who would, for the first time, be going to the jail and P&P office to provide XR-NTX and related treatment. METHOD: The present study focuses on the first seven phases (Assessment through Training) of the ADAPT-ITT framework in the adaptation of the Department of Corrections (DOC) protocol in preparation for a pilot trial for induction in a rural jail and during the transition to a rural community. Expert clinical review and focus groups with key stakeholders in criminal justice supervision and the local providers in the FQHC informed the needed adaptations to the existing XR-NTX protocol for initiation at the jail and ongoing administrations in the community. RESULTS: Findings from stakeholder focus groups, study team review, topical expert review, and a theater test suggested that there were critical adaptations needed in both content and context at the patient and clinic level. CONCLUSION: Health and justice officials should consider the need to tailor and adapt evidence-based approaches for real-world locations that high-risk, justice-involved individuals visit in order to reduce barriers and increase access to critically needed treatment for OUD

    The ATLAS3D project - XXV: Two-dimensional kinematic analysis of simulated galaxies and the cosmological origin of fast and slow rotators

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    We present a detailed two-dimensional stellar dynamical analysis of as ample of 44 cosmological hydrodynamical simulations of individual central galaxies with stellar masses of 2 x 1010Msun ∼≤ Mstar ∼≤ 6x 1011Msun. Kinematic maps of the stellar line-of-sight velocity, velocity dispersion, and higher-order Gauss-Hermite moments h3 and h4 are constructed for each central galaxy and for the most massive satellites. The amount of rotation is quantified using the λR-parameter. The velocity, velocity dispersion, h3, and h4 fields of the simulated galaxies show a diversity similar to observed kinematic maps of early-type galaxies in the ATLAS3D survey. This includes fast (regular), slow, and misaligned rotation, hot spheroids with embedded cold disk components as well as galaxies with counter-rotating cores or central depressions in the velocity dispersion. We link the present-day kinematic properties to the individual cosmological formation histories of the galaxies. In general, major galaxy mergers have a significant influence on the rotation properties resulting in both a spin-down as well as a spin-up of the merger remnant. Lower mass galaxies with significant in-situ formation of stars, or with additional gas-rich major mergers - resulting in a spin-up - in their formation history, form elongated fast rotators with a clear anti-correlation of h3 and v/σ. An additional formation path for fast rotators includes gas-poor major mergers leading to a spin-up of the remnants. This formation path does not result in anti-correlated h3 and v/σ. The galaxies most consistent with the rare class of non-rotating round early-type galaxies grow by gas-poor minor mergers alone. In general, more massive galaxies have less in-situ star formation since z ∼ 2, rotate slower and have older stellar populations. (shortened)PostprintPeer reviewe

    Increasing Employee Awareness of the Signs and Symptoms of Heart Attack and the Need to Use 911 in a State Health Department

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    INTRODUCTION: Early recognition of the signs and symptoms of a heart attack can lead to reduced morbidity and mortality. METHODS: A workplace intervention was conducted among 523 Montana state health department employees in 2003 to increase awareness of the signs and symptoms of heart attack and the need to use 911. All employees received an Act in Time to Heart Attack Signs brochure and wallet card with their paychecks. Act in Time posters were placed in key workplace areas. A weekly e-mail message, including a contest entry opportunity addressing the signs and symptoms of heart attack, was sent to all employees. Baseline and follow-up telephone surveys were conducted to evaluate intervention effectiveness. RESULTS: Awareness of heart attack signs and symptoms and the need to call 911 increased significantly among employees from baseline to follow-up: pain or discomfort in the jaw, neck, or back (awareness increased from 69% to 91%); feeling weak, light-headed, or faint (awareness increased from 79% to 89%); call 911 if someone is having a heart attack or stroke (awareness increased from 84% to 90%). Awareness of chest pain, pain or discomfort in the arms or shoulders, and shortness of breath were more than 90% at baseline and did not increase significantly at follow-up. At baseline, 69% of respondents correctly reported five or more of the signs and symptoms of heart attack; 89% reported correctly at follow-up. CONCLUSION: This low-cost workplace intervention increased awareness of the signs and symptoms of heart attack and the need to call 911
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