3,210 research outputs found

    Beyond the Numbers: Data Use for Continuous Improvement of Programs Serving Disconnected Youth

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    The American Youth Policy Forum (AYPF) conducted a series of in-depth case studies to examine how three programs which serve a disconnected youth population are utilizing data as a tool for continuous program improvement and ongoing accountability. The resulting publication, Beyond the Numbers: Data Use for Continuous Improvement of Programs Serving Disconnected Youth, describes data collection and use at three successful programs, and distills the key lessons learned and issues to consider both for practitioners and policymakers aiming to improve outcomes for the disconnected youth population

    Replicating Test Track Protocols in a Simulator; What Needs to be Matched?

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    Many different experimental methods are used to evaluate driving performance as well as to evaluate the effectiveness of various vehicle safety systems but the results often do not match between different experimental approaches. This study aimed to determine the extent to which results can be matched between a driving simulator and a test track when carefully designed studies are used to replicate findings. This study collected simulator data on the National Advanced Driving Simulator (NADS) at the University of Iowa to replicate findings concerning Forward-Crash-Warning interface effectiveness at the Vehicle Research and Test Center (VRTC), East Liberty Ohio. The simulator used a virtual replica of the test track as well as a road course. Event choreography and scanning behavior were compared. Results indicate that results from the simulator were similar to those obtained on the test track. This indicates simulators can replicate findings for the test track and are a valuable tool. Careful experimental design is required to match the event choreography to insure an appropriate comparison. An exact match of the driving environment was not needed for this interface evaluation to obtain comparable results. The extent to which matching motion cues was not evaluated and may prove challenging in simulators without motion systems

    Phonon gap and localization lengths in floppy materials

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    Gels of semi-flexible polymers, network glasses made of low valence elements, softly compressed ellipses and dense suspensions under flow are examples of floppy materials. These systems present collective motions with almost no restoring force. We study theoretically and numerically the frequency-dependence of the response of these materials, and the length scales that characterize their elasticity. We show that isotropic floppy elastic networks present a phonon gap for frequencies smaller than a frequency ω∗\omega^* governed by coordination, and that the elastic response is localized on a length scale lc∌1/ω∗l_c\sim 1/\sqrt{\omega^*} that diverges as the phonon gap vanishes (with a logarithmic correction in the two dimensional case). lcl_c also characterizes velocity correlations under shear, whereas another length scale l∗∌1/ω∗l^*\sim 1/\omega^* characterizes the effect of pinning boundaries on elasticity. We discuss the implications of our findings for suspensions flows, and the correspondence between floppy materials and amorphous solids near unjamming, where lcl_c and l∗l^* have also been identified but where their roles are not fully understood

    Shwartzman reaction after human renal homotransplantation.

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    In three human recipients, five renal homografts were destroyed within a few minutes to hours after their revascularization in the new host. The kidneys, removed one to 54 days later, had cortical necrosis. The major vessels were patent, but the arterioles and glomeruli were the site of fibrin deposition. There was little or no fixation of host immunoglobulins in the homografts. The findings were characteristic of a generalized Shwartzman reaction. Although the cause (or causes) of the Shwartzman reaction in our patients is not known, they may have been conditioned by the bacterial contamination and hemolysis that often attend hemodialysis, by immunosuppression and by the transplantation itself. Some of the patients have preformed lymphocytotoxic antibodies. Thus, certain patients may be predisposed. High-risk patients should be recognized and treated prophylactically with anticoagulants

    Direct and indirect effects of mood on risk decision making in safety-critical workers

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    The study aimed to examine the direct influence of specific moods (fatigue, anxiety, happiness) on risk in safety-critical decision making. It further aimed to explore indirect effects, specifically, the potential mediating effects of information processing assessed using a goodness-of-simulation task. Trait fatigue and anxiety were associated with an increase in risk taking on the Safety-Critical Personal Risk Inventory (S-CPRI), however the effect of fatigue was partialled out by anxiety. Trait happiness, in contrast was related to less risky decision making. Findings concerning the ability to simulate suggest that better simulators made less risky decisions. Anxious workers were generally less able to simulate. It is suggested that in this safety-critical environment happiness had a direct effect on risk decision making while the effect of trait anxiety was mediated by goodness-of-simulation

    Spin polarization and magneto-luminescence of confined electron-hole systems

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    A BCS-like variational wave-function, which is exact in the infinite field limit, is used to study the interplay among Zeeman energies, lateral confinement and particle correlations induced by the Coulomb interactions in strongly pumped neutral quantum dots. Band mixing effects are partially incorporated by means of field-dependent masses and g-factors. The spin polarization and the magneto-luminescence are computed as functions of the number of electron-hole pairs present in the dot and the applied magnetic field.Comment: To appear in Phys. Rev.

    Youth sport during the COVID-19 pandemic: The influence of race and affluence on parents’ perspectives of youth participation

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    COVID-19 restrictions led to a nearly 50% decline in youth sport participation across the United States (Dorsch et al., 2021). Today, communities and sport organizations have resumed sport. However, research has yet to fully elucidate how COVID-19 restrictions impacted youth participation across different sociodemographic groups during the pandemic. The present study explored the association between race and affluence and their relationship with parents' attitudes toward children's youth sport participation before, during, and after the COVID-19 pandemic. Online questionnaires were completed by a nationally representative sample of 3706 parents (Mage = 39.57 ± 9.03 years) who had a child regularly participating in youth sport before COVID-19. Multivariate Analyses of Variance using Tukey post-hoc tests were conducted to examine the main effect differences by race and affluence and the interactive effects of race and affluence. Results suggest that race and affluence -- independently and in combination -- were salient categorical variables of children's weekly hours of sport participation during the COVID-19 pandemic. Findings highlight that White*high affluent groups had the highest rates of sport participation during the COVID-19 pandemic and that these families desire to invest more time and money at greater rates upon returning. Theoretically, designed intersectionality research is recommended to explore further effects of race and affluence in youth sport

    Perceptions of the intergroup structure and anti-Asian prejudice amongst white Australians

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    Proof oSubjective intergroup beliefs and authoritarianism were assessed in a field study (N= 255) of White Australians’ anti-Asian stereotyping and prejudice. A social identity analysis of intergroup prejudice was adopted, such that perceptions of the intergroup structure (instability, permeability, legitimacy and higher ingroup status) were proposed as predictors of higher prejudice (blatant and covert) and less favorable stereotyping. Consistent with the social identity approach, both independent and interacting roles for sociostructural predictors of Anti-Asian bias were observed, even after demographic and personality variables were controlled. For example, perceived legitimacy was associated with higher prejudice when White Australians’ status position relative to Asian Australians was valued. Moreover, when participants evaluated Whites’ position as unstable and high status or legitimate, perceptions of permeable intergroup boundaries were associated with anti-Asian bias. The present findings demonstrate status protection responses in advantaged group members in a field setting, lending weight to the contention that perceptions of sociostructural threat interact to predict outgroup derogation. Implications for theories of intergroup relations are discussed
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