38 research outputs found

    Collective Power to Create Political Change: Increasing the Political Efficacy and Engagement of Social Workers

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    Because social workers are called to challenge social injustices and create systemic change to support the well-being of individuals and communities, it is essential that social workers develop political efficacy: belief that the political system can work and they can influence the system. This study explored the impact of an intensive political social work curriculum on political efficacy and planned political engagement among social work students and practitioners. The findings suggest this model of delivering a political social work curriculum effectively increases internal, external, and overall political efficacy, and that increasing political efficacy has promise for increasing future political engagement

    COSMOS-Web: Intrinsically Luminous z≳\gtrsim10 Galaxy Candidates Test Early Stellar Mass Assembly

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    We report the discovery of 15 exceptionally luminous 10≲z≲1410\lesssim z\lesssim14 candidate galaxies discovered in the first 0.28 deg2^2 of JWST/NIRCam imaging from the COSMOS-Web Survey. These sources span rest-frame UV magnitudes of βˆ’20.5>MUV>βˆ’22-20.5>M_{\rm UV}>-22, and thus constitute the most intrinsically luminous z≳10z\gtrsim10 candidates identified by JWST to-date. Selected via NIRCam imaging with Hubble ACS/F814W, deep ground-based observations corroborate their detection and help significantly constrain their photometric redshifts. We analyze their spectral energy distributions using multiple open-source codes and evaluate the probability of low-redshift solutions; we conclude that 12/15 (80%) are likely genuine z≳10z\gtrsim10 sources and 3/15 (20%) likely low-redshift contaminants. Three of our z∼12z\sim12 candidates push the limits of early stellar mass assembly: they have estimated stellar masses ∼5Γ—109 MβŠ™\sim5\times10^{9}\,M_\odot, implying an effective stellar baryon fraction of Ο΅β‹†βˆΌ0.2βˆ’0.5\epsilon_{\star}\sim0.2-0.5, where ϡ⋆≑M⋆/(fbMhalo)\epsilon_{\star}\equiv M_{\star}/(f_{b}M_{halo}). The assembly of such stellar reservoirs is made possible due to rapid, burst-driven star formation on timescales <<100\,Myr where the star-formation rate may far outpace the growth of the underlying dark matter halos. This is supported by the similar volume densities inferred for Mβ‹†βˆΌ1010 MβŠ™M_\star\sim10^{10}\,M_\odot galaxies relative to Mβ‹†βˆΌ109 MβŠ™M_\star\sim10^{9}\,M_\odot -- both about 10βˆ’610^{-6} Mpcβˆ’3^{-3} -- implying they live in halos of comparable mass. At such high redshifts, the duty cycle for starbursts would be of order unity, which could cause the observed change in the shape of the UVLF from a double powerlaw to Schechter at zβ‰ˆ8z\approx8. Spectroscopic redshift confirmation and ensuing constraints of their masses will be critical to understanding how, and if, such early massive galaxies push the limits of galaxy formation in Ξ›\LambdaCDM.Comment: 30 pages, 9 figures; ApJ submitte

    Diversity of Murine Norovirus Strains Isolated from Asymptomatic Mice of Different Genetic Backgrounds within a Single U.S. Research Institute

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    Antibody prevalence studies in laboratory mice indicate that murine norovirus (MNV) infections are common, but the natural history of these viruses has not been fully established. This study examined the extent of genetic diversity of murine noroviruses isolated from healthy laboratory mice housed in multiple animal facilities within a single, large research institute- the National Institute of Allergy and Infectious Diseases of the National Institutes of Health (NIAID-NIH) in Bethesda, Maryland, U.S. Ten distinct murine norovirus strains were isolated from various tissues and feces of asymptomatic wild type sentinel mice as well as asymptomatic immunodeficient (RAG 2βˆ’/βˆ’) mice. The NIH MNV isolates showed little cytopathic effect in permissive RAW264.7 cells in early passages, but all isolates examined could be adapted to efficient growth in cell culture by serial passage. The viruses, although closely related in genome sequence, were distinguishable from each other according to facility location, likely due to the introduction of new viruses into each facility from separate sources or vendors at different times. Our study indicates that the murine noroviruses are widespread in these animal facilities, despite rigorous guidelines for animal care and maintenance

    Uncovering a Massive z~7.65 Galaxy Hosting a Heavily Obscured Radio-Loud QSO Candidate in COSMOS-Web

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    In this letter, we report the discovery of the highest redshift, heavily obscured, radio-loud QSO candidate selected using JWST NIRCam/MIRI, mid-IR, sub-mm, and radio imaging in the COSMOS-Web field. Using multi-frequency radio observations and mid-IR photometry, we identify a powerful, radio-loud (RL), growing supermassive black hole (SMBH) with significant spectral steepening of the radio SED (f1.32GHz∼2f_{1.32 \mathrm{GHz}} \sim 2 mJy, q24ΞΌm=βˆ’1.1q_{24\mu m} = -1.1, Ξ±1.32βˆ’3GHz=βˆ’1.2\alpha_{1.32-3\mathrm{GHz}}=-1.2, Δα=βˆ’0.4\Delta \alpha = -0.4). In conjunction with ALMA, deep ground-based observations, ancillary space-based data, and the unprecedented resolution and sensitivity of JWST, we find no evidence of QSO contribution to the UV/optical/NIR data and thus infer heavy amounts of obscuration (NH>1023_{\mathrm{H}} > 10^{23} cmβˆ’2^{-2}). Using the wealth of deep UV to sub-mm photometric data, we report a singular solution photo-z of zphotz_\mathrm{phot} = 7.65βˆ’0.3+0.4^{+0.4}_{-0.3} and estimate an extremely massive host-galaxy (log⁑M⋆=11.92Β±0.06 MβŠ™\log M_{\star} = 11.92 \pm 0.06\,\mathrm{M}_{\odot}). This source represents the furthest known obscured RL QSO candidate, and its level of obscuration aligns with the most representative but observationally scarce population of QSOs at these epochs.Comment: Submitted to ApJL, Comments welcom

    Does Respondent Driven Sampling Alter the Social Network Composition and Health-Seeking Behaviors of Illicit Drug Users Followed Prospectively?

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    Respondent driven sampling (RDS) was originally developed to sample and provide peer education to injection drug users at risk for HIV. Based on the premise that drug users' social networks were maintained through sharing rituals, this peer-driven approach to disseminate educational information and reduce risk behaviors capitalizes and expands upon the norms that sustain these relationships. Compared with traditional outreach interventions, peer-driven interventions produce greater reductions in HIV risk behaviors and adoption of safer behaviors over time, however, control and intervention groups are not similarly recruited. As peer-recruitment may alter risk networks and individual risk behaviors over time, such comparison studies are unable to isolate the effect of a peer-delivered intervention. This analysis examines whether RDS recruitment (without an intervention) is associated with changes in health-seeking behaviors and network composition over 6 months. New York City drug users (Nβ€Š=β€Š618) were recruited using targeted street outreach (TSO) and RDS (2006–2009). 329 non-injectors (RDSβ€Š=β€Š237; TSOβ€Š=β€Š92) completed baseline and 6-month surveys ascertaining demographic, drug use, and network characteristics. Chi-square and t-tests compared RDS- and TSO-recruited participants on changes in HIV testing and drug treatment utilization and in the proportion of drug using, sex, incarcerated and social support networks over the follow-up period. The sample was 66% male, 24% Hispanic, 69% black, 62% homeless, and the median age was 35. At baseline, the median network size was 3, 86% used crack, 70% used cocaine, 40% used heroin, and in the past 6 months 72% were tested for HIV and 46% were enrolled in drug treatment. There were no significant differences by recruitment strategy with respect to changes in health-seeking behaviors or network composition over 6 months. These findings suggest no association between RDS recruitment and changes in network composition or HIV risk, which supports prior findings from prospective HIV behavioral surveillance and intervention studies

    Unveiling the distant Universe: Characterizing zβ‰₯9z\ge9 Galaxies in the first epoch of COSMOS-Web

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    We report the identification of 15 galaxy candidates at zβ‰₯9z\ge9 using the initial COSMOS-Web JWST observations over 77 arcmin2^2 through four NIRCam filters (F115W, F150W, F277W, F444W) with an overlap with MIRI (F770W) of 8.7 arcmin2^2. We fit the sample using several publicly-available SED fitting and photometric redshift codes and determine their redshifts between z=9.3z=9.3 and z=10.9z=10.9 (⟨z⟩=10.0\langle z\rangle=10.0), UV-magnitudes between MUV_{\rm UV} = βˆ’-21.2 and βˆ’-19.5 (with ⟨\langle MUV⟩=βˆ’20.2_{\rm UV}\rangle=-20.2) and rest-frame UV slopes (⟨β⟩=βˆ’2.4\langle \beta\rangle=-2.4). These galaxies are, on average, more luminous than most zβ‰₯9z\ge9 candidates discovered by JWST so far in the literature, while exhibiting similar blue colors in their rest-frame UV. The rest-frame UV slopes derived from SED-fitting are blue (β∼\beta\sim[βˆ’-2.0, βˆ’-2.7]) without reaching extremely blue values as reported in other recent studies at these redshifts. The blue color is consistent with models that suggest the underlying stellar population is not yet fully enriched in metals like similarly luminous galaxies in the lower redshift Universe. The derived stellar masses with ⟨log⁑10(\langle \log_{\rm 10} (M⋆/_\star/MβŠ™)βŸ©β‰ˆ8βˆ’9_\odot)\rangle\approx8-9 are not in tension with the standard Ξ›\LambdaCDM model and our measurement of the volume density of such UV luminous galaxies aligns well with previously measured values presented in the literature at z∼9βˆ’10z\sim9-10. Our sample of galaxies, although compact, are significantly resolved.Comment: Submitted to Ap
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