19,530 research outputs found
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Will I Be Victimized at School Today? How Schools Influence the Victimization Experiences of Asian American Teenagers
Schools can play an influential role in the victimization experiences of Asian American youth. We investigated the extent to which characteristics of schools—their disciplinary structure, guardianship role, and the opportunities for exposure to victimization they provide—related to whether Asian American adolescents were physically or socially victimized. Our sample included 1,303 adolescents (M
age = 14.8 years) from six waves of the School Crime Supplement of the National Crime Victimization Survey. Results from logistic regression models show that disciplinary structure and guardianship, in the form of school security measures, were unrelated to victimization. Asian American adolescents with supportive peers had lower odds of physical victimization (odds ratio [OR] = 0.16; p < .01) while those exposed to school gangs and physical fights had higher odds of social victimization (OR = 2.90; p < .001 and OR = 4.97; p < .01, respectively). Our findings underscore the need for schools to consider strategies beyond commonplace school disciplinary structures and security measures to protect Asian American adolescents from victimization
Investigating the Relationship between Environment and Active Galactic Nuclei activity at High Redshift
This thesis presents an investigation into the relationship between large-scale structure
environment and Active Galactic Nuclei (AGN) activity at high redshift. To accomplish
this, the environments of AGN are studied from two complementary perspectives.
Firstly, various observations of a specific large-scale structure at z = 2.3 are used to assess
the level of AGN activity in relation to the field. The main result of this study is that
both the emission-line and X-ray selected AGN populations are significantly enhanced;
X-ray detected Lyman Alpha Emitters (LAEs), however, are not found to be significantly
enhanced.
The host galaxy properties of z ~ 1 X-ray sources are then derived and studied
in detail. Confirming previous results, X-ray sources are found in optically luminous
(MB ~< −20.5mag), massive (log(M∗/ M⊙) ≥ 10.5) red and blue hosts. A larger fraction of
red/green hosts harbour obscured (log(NH) ≥ 22) AGN than blue, with the most obscured
sources (log(NH) ≥ 23.5) also being more frequently found in red/green host galaxies
than blue.
The second approach used the 3rd-nearest neighbour measure to study the environment
of X-ray hosts at z ~ 1, accounting for their optical colour, luminosity and stellar
mass. A main new and important result is that X-ray hosts are found in regions of enhanced
density compared to optical galaxies of equivalent mass, which is not due to the
observed colour-density relation at z ~ 1. The enhancement is found to be most significant
at the reddest colours, brightest luminosities, and highest stellar masses.
The results from this thesis show that the dense environments probed in this work
generally promote AGN activity. This is probably not due to major mergers, but could be
due to an increased probability of minor mergers/interactions and/or milder environmental
processes triggering nuclear activity. Alternatively, perhaps there is some other galaxy
property (e.g., residing in higher mass haloes) which is conducive to AGN activity
Performance, physiological, and oculometer evaluation of VTOL landing displays
A methodological approach to measuring workload was investigated for evaluation of new concepts in VTOL aircraft displays. Physiological, visual response, and conventional flight performance measures were recorded for landing approaches performed in the NASA Visual Motion Simulator (VMS). Three displays (two computer graphic and a conventional flight director), three crosswind amplitudes, and two motion base conditions (fixed vs. moving base) were tested in a factorial design. Multivariate discriminant functions were formed from flight performance and/or visual response variables. The flight performance variable discriminant showed maximum differentation between crosswind conditions. The visual response measure discriminant maximized differences between fixed vs. motion base conditions and experimental displays. Physiological variables were used to attempt to predict the discriminant function values for each subject/condition trial. The weights of the physiological variables in these equations showed agreement with previous studies. High muscle tension, light but irregular breathing patterns, and higher heart rate with low amplitude all produced higher scores on this scale and thus represent higher workload levels
ON THE FACILITATIVE ROLE OF THE ECONOMIST IN ECONOMIC DEVELOPMENT - CASE STUDY OF A GEORGIA SHRIMP HARBOR INVESTMENT
Community/Rural/Urban Development,
The Potential Impact of a Proposed Ban on the Sale of U.S. Horses for Slaughter and Human Consumption
Both federal and state governments in the United States are being asked to enact laws that would make slaughtering of horses for human consumption illegal. In the past, the United States was one of the principal exporters of horsemeat to Europe. This paper examines the impacts of a proposed ban on the U.S. horse industry and the U.S. export market for horsemeat. Findings indicate a loss of approximately $300 per horse in the United States as a result of such a ban. The supply of U.S. exported horsemeat has declined during the past decade. The results suggest that the most significant factors influencing this decline are lower real prices and competing imports.horse slaughter, horsemeat, meat exports, Agricultural and Food Policy, Livestock Production/Industries,
Domestic work, learning and literacy practices across transnational space
This paper explores the learning experiences and literacy practices of a group of female migrant domestic workers from Nepal, reporting on ethnographic data collected between 2008 and 2013. Drawing on the conceptualisation of literacy as a social practice, as well as the notion of translocational positionality, it examines the way in which the women’s emerging literacy practices in English interacted with their experiences as migrant workers. It argues that understanding the transnational nature of the women’s lives is essential to understanding the complex ways in which literacy was threaded through their social and material practices. In doing so it points to the need for a more complex conceptualisation of context and of the relationship between the local and global within literacy research, which pays attention to the way in which literacy practices interact with processes entailing movement and positioning across boundaries and between different transnational spaces
The effect of a scanning flat fold mirror on a CMB B-mode experiment
We investigate the possibility of using a flat-fold beam steering mirror for
a CMB B-mode experiment. An aluminium flat-fold mirror is found to add
0.075% polarization, which varies in a scan synchronous way. Time-domain
simulations of a realistic scanning pattern are performed, and the effect on
the power-spectrum illustrated and a possible method of correction applied.Comment: 8 pages, 5 figures. Accepted for publication in Rev Sci Ins
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The human silent information regulator (Sir)2 homologue hSIRT3 is a mitochondrial nicotinamide adenine dinucleotide-dependent deacetylase.
The yeast silent information regulator (Sir)2 protein links cellular metabolism and transcriptional silencing through its nicotinamide adenine dinucleotide (NAD)-dependent histone deacetylase activity. We report that mitochondria from mammalian cells contain intrinsic NAD-dependent deacetylase activity. This activity is inhibited by the NAD hydrolysis product nicotinamide, but not by trichostatin A, consistent with a class III deacetylase. We identify this deacetylase as the nuclear-encoded human Sir2 homologue hSIRT3, and show that hSIRT3 is located within the mitochondrial matrix. Mitochondrial import of hSIRT3 is dependent on an NH2-terminal amphipathic alpha-helix rich in basic residues. hSIRT3 is proteolytically processed in the mitochondrial matrix to a 28-kD product. This processing can be reconstituted in vitro with recombinant mitochondrial matrix processing peptidase (MPP) and is inhibited by mutation of arginines 99 and 100. The unprocessed form of hSIRT3 is enzymatically inactive and becomes fully activated in vitro after cleavage by MPP. These observations demonstrate the existence of a latent class III deacetylase that becomes catalytically activated upon import into the human mitochondria
Assessing somatization in urologic chronic pelvic pain syndrome
BACKGROUND: This study examined the prevalence of somatization disorder in Urological Chronic Pelvic Pain Syndrome (UCPPS) and the utility of two self-report symptom screening tools for assessment of somatization in patients with UCPPS.
METHODS: The study sample included 65 patients with UCPPS who enrolled in the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Study at Washington University. Patients completed the PolySymptomatic PolySyndromic Questionnaire (PSPS-Q) (n = 64) and the Patient Health Questionnaire-15 Somatic Symptom Severity Scale (PHQ-15) (n = 50). Review of patient medical records found that only 47% (n = 30) contained sufficient documentation to assess Perley-Guze criteria for somatization disorder.
RESULTS: Few (only 6.5%) of the UCPPS sample met Perley-Guze criteria for definite somatization disorder. Perley-Guze somatization disorder was predicted by definite PSPS-Q somatization with at least 75% sensitivity and specificity. Perley-Guze somatization disorder was predicted by severe (\u3e 15) PHQ-15 threshold that had \u3e 90% sensitivity and specificity but was met by only 16% of patients. The moderate (\u3e 10) PHQ-15 threshold had higher sensitivity (100%) but lower specificity (52%) and was met by 52% of the sample.
CONCLUSIONS: The PHQ-15 is brief, but it measures symptoms constituting only one dimension of somatization. The PSPS-Q uniquely captures two conceptual dimensions inherent in the definition of somatization disorder, both number of symptoms and symptom distribution across multiple organ systems, with relevance for UCPPS as a syndrome that is not just a collection of urological symptoms but a broader syndrome with symptoms extending beyond the urological system
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