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The theoretical and empirical links between bullying behavior and male sexual violence perpetration
Bullying experiences and male sexual violence (SV) perpetration are major public health problems, and while extant literature suggests that they may share some developmental correlates, there is no established empirical link between being a perpetrator or victim of bullying and SV perpetration in the literature. Nonetheless, some SV prevention programs in the U.S. include bullying prevention components for elementary and middle-school aged children. Research is needed to test the hypothesized links between bullying experiences and SV perpetration to determine whether bullying prevention programs are likely to prevent SV perpetration. The purpose of this paper is to present results from a review of research on each of these topics and to discuss the potential shared and unique risk and protective factors within a social-ecological framework. The paper concludes with suggested directions for future research
Jet production in charged current deep inelastic e⁺p scatteringat HERA
The production rates and substructure of jets have been studied in charged current deep inelastic e⁺p scattering for Q² > 200 GeV² with the ZEUS detector at HERA using an integrated luminosity of 110.5 pb⁻¹. Inclusive jet cross sections are presented for jets with transverse energies E_{T}^{jet} > 5 GeV. Measurements of the mean subjet multiplicity, 〈n_{sbj}〉, of the inclusive jet sample are presented. Predictions based on parton-shower Monte Carlo models and next-to-leading-order QCD calculations are compared to the measurements. The value of α_{s} (M_{z}), determined from 〈n_{sbj}〉 at y_{cut} = 10⁻² for jets with 25 < E_{T}^{jet} < 119 GeV, is α_{s} (M_{z}) = 0.1202 ± 0.0052 (stat.)_{-0.0019}^{+0.0060} (syst.)_{-0.0053}^{+0.0065} (th.). The mean subjet multiplicity as a function of Q² is found to be consistent with that measured in NC DIS
Multijet production in neutral current deep inelastic scattering at HERA and determination of α_{s}
Multijet production rates in neutral current deep inelastic scattering have been measured in the range of exchanged boson virtualities 10 5 GeV and –1 < η_{LAB}^{jet} < 2.5. Next-to-leading-order QCD calculations describe the data well. The value of the strong coupling constant α_{s} (M_{z}), determined from the ratio of the trijet to dijet cross sections, is α_{s} (M_{z}) = 0.1179 ± 0.0013 (stat.)_{-0.0046}^{+0.0028}(exp.)_{-0.0046}^{+0.0028}(th.)
The dependence of dijet production on photon virtuality in ep collisions at HERA
The dependence of dijet production on the virtuality of the exchanged photon,
Q^2, has been studied by measuring dijet cross sections in the range 0 < Q^2 <
2000 GeV^2 with the ZEUS detector at HERA using an integrated luminosity of
38.6 pb^-1.
Dijet cross sections were measured for jets with transverse energy E_T^jet >
7.5 and 6.5 GeV and pseudorapidities in the photon-proton centre-of-mass frame
in the range -3 < eta^jet <0. The variable xg^obs, a measure of the photon
momentum entering the hard process, was used to enhance the sensitivity of the
measurement to the photon structure. The Q^2 dependence of the ratio of low- to
high-xg^obs events was measured.
Next-to-leading-order QCD predictions were found to generally underestimate
the low-xg^obs contribution relative to that at high xg^obs. Monte Carlo models
based on leading-logarithmic parton-showers, using a partonic structure for the
photon which falls smoothly with increasing Q^2, provide a qualitative
description of the data.Comment: 35 pages, 6 eps figures, submitted to Eur.Phys.J.
Beauty photoproduction measured using decays into muons in dijet events in ep collisions at =318 GeV
The photoproduction of beauty quarks in events with two jets and a muon has
been measured with the ZEUS detector at HERA using an integrated luminosity of
110 pb. The fraction of jets containing b quarks was extracted from the
transverse momentum distribution of the muon relative to the closest jet.
Differential cross sections for beauty production as a function of the
transverse momentum and pseudorapidity of the muon, of the associated jet and
of , the fraction of the photon's momentum participating in
the hard process, are compared with MC models and QCD predictions made at
next-to-leading order. The latter give a good description of the data.Comment: 32 pages, 6 tables, 7 figures Table 6 and Figure 7 revised September
200
Search for a narrow charmed baryonic state decaying to D^*+/- p^-/+ in ep collisions at HERA
A resonance search has been made in the D^*+/- p^-/+ invariant-mass spectrum
with the ZEUS detector at HERA using an integrated luminosity of 126 pb^-1. The
decay channels D^*+ -> D^0 pi^+_s -> (K^- pi^+) pi^+_s and D^*+ -> D^0 pi^+_s
-> (K^- pi^+ pi^+ pi^-) pi^+_s (and the corresponding antiparticle decays) were
used to identify D^*+/- mesons. No resonance structure was observed in the
D^*+/- p^-/+ mass spectrum from more than 60000 reconstructed D^*+/- mesons.
The results are not compatible with a report of the H1 Collaboration of a
charmed pentaquark, Theta^0_c.Comment: 22 pages, 7 figures, 1 table; minor text revisions; 2 references
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Current drinking and health-risk behaviors among male high school students in central Thailand
<p>Abstract</p> <p>Background</p> <p>Alcohol drinking is frequently related to behavioral problems, which lead to a number of negative consequences. This study was to evaluate the characteristics of male high school students who drink, the drinking patterns among them, and the associations between current drinking and other health risk behaviors which focused on personal safety, violence-related behaviors, suicide and sexual behaviors.</p> <p>Method</p> <p>A cross-sectional study was conducted to explore current alcohol drinking and health-risk behaviors among male high school students in central Thailand. Five thousand one hundred and eighty four male students were classified into 2 groups according to drinking in the previous 30 days (yes = 631, no = 4,553). Data were collected by self-administered, anonymous questionnaire which consisted of 3 parts: socio-demographic factors, health-risk behaviors and alcohol drinking behavior during the past year from December 2007 to February 2008.</p> <p>Results</p> <p>The results showed that the percent of current drinking was 12.17. Most of them were 15-17 years (50.21%). Socio-demographic factors such as age, educational level, residence, cohabitants, grade point average (GPA), having a part time job and having family members with alcohol/drug problems were significantly associated with alcohol drinking (p < 0.05). Multiple logistic regression analysis, after adjusting for socio-demographic factors, revealed that health-risk behavioral factors were associated with current alcohol consumption: often drove after drinking alcohol (OR = 3.10, 95% CI = 1.88-5.12), often carried a weapon (OR = 3.51, 95% CI = 2.27-5.42), often got into a physical fight without injury (OR = 3.06, 95% CI = 1.99-4.70), dating violence (OR = 2.58, 95% CI = 1.79-3.71), seriously thought about suicide (OR = 2.07, 95% CI = 1.38-3.11), made a suicide plan (OR = 2.10, 95% CI = 1.43-3.08), ever had sexual intercourse (OR = 5.62, 95% CI = 4.33-7.29), alcohol or drug use before last sexual intercourse (OR = 2.55, 95% CI = 1.44-4.53), and got someone pregnant (OR = 3.99, 95% CI = 1.73-9.25).</p> <p>Conclusions</p> <p>An increased risk of health-risk behaviors, including driving vehicles after drinking, violence-related behaviors, sad feelings and attempted suicide, and sexual behaviors was higher among drinking students that led to significant health problems. Effective intervention strategies (such as a campaign mentioning the adverse health effects and social consequences to the risk groups, and encouraging parental and community efforts to prevent drinking) among adolescents should be implemented to prevent underage drinking and adverse consequences.</p
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