Views of young, rural African Americans of the role of community social institutions in HIV prevention.

BACKGROUND: We explored rural African American youths' perceptions about the role of community social institutions in addressing HIV. METHODS: We conducted four focus groups with African Americans aged 16 to 24 years in two rural counties in North Carolina. Groups were stratified by gender and risk status. We used a grounded theory approach to content analysis. RESULTS: Participants identified four social institutions as primary providers of HIV-related health promotion efforts: faith organizations, schools, politicians, and health agencies. They reported perceiving a lack of involvement in HIV prevention by faith-based organizations, constraints of abstinence-based sex education policies, politicians' lack of interest in addressing broader HIV determinants, and inadequacies in health agency services, and viewed all of these as being counter-productive to HIV prevention efforts. CONCLUSIONS: Youth have important insights about local social institutions that should be considered when designing HIV prevention interventions that partner with local organizations

Energy Flow in the Hadronic Final State of Diffractive and Non-Diffractive Deep-Inelastic Scattering at HERA

An investigation of the hadronic final state in diffractive and non--diffractive deep--inelastic electron--proton scattering at HERA is presented, where diffractive data are selected experimentally by demanding a large gap in pseudo --rapidity around the proton remnant direction. The transverse energy flow in the hadronic final state is evaluated using a set of estimators which quantify topological properties. Using available Monte Carlo QCD calculations, it is demonstrated that the final state in diffractive DIS exhibits the features expected if the interaction is interpreted as the scattering of an electron off a current quark with associated effects of perturbative QCD. A model in which deep--inelastic diffraction is taken to be the exchange of a pomeron with partonic structure is found to reproduce the measurements well. Models for deep--inelastic $ep$ scattering, in which a sizeable diffractive contribution is present because of non--perturbative effects in the production of the hadronic final state, reproduce the general tendencies of the data but in all give a worse description.Comment: 22 pages, latex, 6 Figures appended as uuencoded fil

A Search for Selectrons and Squarks at HERA

Data from electron-proton collisions at a center-of-mass energy of 300 GeV are used for a search for selectrons and squarks within the framework of the minimal supersymmetric model. The decays of selectrons and squarks into the lightest supersymmetric particle lead to final states with an electron and hadrons accompanied by large missing energy and transverse momentum. No signal is found and new bounds on the existence of these particles are derived. At 95% confidence level the excluded region extends to 65 GeV for selectron and squark masses, and to 40 GeV for the mass of the lightest supersymmetric particle.Comment: 13 pages, latex, 6 Figure

Forestry for a low carbon future. Integrating forests and wood products in climate change strategies

Following the introduction, Chapter 2 provides an overview of mitigation in the forest sector, addressing the handling of forests under UNFCCC. Chapters 3 to 5 focus on forest-based mitigation options – afforestation, reforestation, REDD+ and forest management – and Chapters 6 and 7 focus on wood-product based options – wood energy and green building and furnishing. The publication describes these activities in the context of UNFCCC rules, assessing their mitigation potential and economic attrac tiveness as well as opportunities and challenges for implementation. Chapter 8 discusses the different considerations involved in choosing the right mix of options as well as some of the instruments and means for implementation. Chapter 8 also highlights the co-benefits generated by forest-based mitigation and emphasizes that economic assessment of mitigation options needs to take these benefits into account. The concluding chapter assesses national commitments under UNFCCC involving forest miti gation and summarizes the challenges and opportunities

Viral nanomotors for packaging of dsDNA and dsRNA

While capsid proteins are assembled around single-stranded genomic DNA or RNA in rod-shaped viruses, the lengthy double-stranded genome of other viruses is packaged forcefully within a preformed protein shell. This entropically unfavourable DNA or RNA packaging is accomplished by an ATP-driven viral nanomotor, which is mainly composed of two components, the oligomerized channel and the packaging enzymes. This intriguing DNA or RNA packaging process has provoked interest among virologists, bacteriologists, biochemists, biophysicists, chemists, structural biologists and computational scientists alike, especially those interested in nanotechnology, nanomedicine, AAA+ family proteins, energy conversion, cell membrane transport, DNA or RNA replication and antiviral therapy. This review mainly focuses on the motors of double-stranded DNA viruses, but double-stranded RNA viral motors are also discussed due to interesting similarities. The novel and ingenious configuration of these nanomotors has inspired the development of biomimetics for nanodevices. Advances in structural and functional studies have increased our understanding of the molecular basis of biological movement to the point where we can begin thinking about possible applications of the viral DNA packaging motor in nanotechnology and medical applications

A Measurement of the Proton Structure Function F ⁣2(x,Q2)F_{\!2}(x,Q^2)

A measurement of the proton structure function $F_{\!2}(x,Q^2)$ is reported for momentum transfer squared $Q^2$ between 4.5 $GeV^2$ and 1600 $GeV^2$ and for Bjorken $x$ between $1.8\cdot10^{-4}$ and 0.13 using data collected by the HERA experiment H1 in 1993. It is observed that $F_{\!2}$ increases significantly with decreasing $x$, confirming our previous measurement made with one tenth of the data available in this analysis. The $Q^2$ dependence is approximately logarithmic over the full kinematic range covered. The subsample of deep inelastic events with a large pseudo-rapidity gap in the hadronic energy flow close to the proton remnant is used to measure the "diffractive" contribution to $F_{\!2}$.Comment: 32 pages, ps, appended as compressed, uuencoded fil