4,866 research outputs found

    TOBACCO AND THE ECONOMY: FARMS, JOBS, AND COMMUNITIES

    Get PDF
    Public health policies intended to reduce the incidence of smoking-related disease adversely affect thousands of tobacco farmers, manufacturers, and other businesses that produce, distribute, and sell tobacco products. This report assesses the likely impacts of declining tobacco demand, and identifies the types of workers, farms, businesses, and communities that are most vulnerable to loss of tobacco income and jobs. The dollar impact on the farm sector of a reduction in cigarette demand will be smaller than that experienced by manufacturing, wholesale, retail, and transportation businesses, but tobacco farms and their communities may have the most difficulty adjusting. Many tobacco farmers lack good alternatives to tobacco, and they have tobacco-specific equipment, buildings, and experience. Most communities will make the transition to a smaller tobacco industry with little difficulty, because tobacco accounts for a small share of the local economy. However, a number of counties depend on tobacco for a significant share of local income.Community/Rural/Urban Development, Crop Production/Industries,

    Does the quark cluster model predict any isospin two dibaryon resonance?

    Get PDF
    We analyze the possible existence of a resonance in the JP=0J^P=0^- channel with isospin two by means of nucleon-Δ\Delta interactions based on the constituent quark model. We solve the bound state and the scattering problem using two different potentials, a local and a non-local one. The non-local potential results to be the more attractive, although not enough to generate the experimentally predicted resonance.Comment: 9 pages in Latex (revtex), 2 eps figures available under reques

    Quark Cluster Model Study of Isospin-Two Dibaryons

    Get PDF
    Based on a quark cluster model for the non-strange sector that reproduces reasonably well the nucleon-nucleon system and the excitation of the Δ\Delta isobar, we generate a nucleon-Δ\Delta interaction and present the predictions for the several isospin two channels. The only attractive channels are 0+0^+ and 00^-, but not attractive enough to generate a resonance. If a resonance is artificially generated and is required to have the observed experimental mass, then our model predicts a width that agrees with the experimental result.Comment: 12 pages, 5 poscript figures available under request. To appear in Phys. Rev.

    J/Psi Propagation in Hadronic Matter

    Full text link
    We study J/ψ\psi propagation in hot hadronic matter using a four-flavor chiral Lagrangian to model the dynamics and using QCD sum rules to model the finite size effects manifested in vertex interactions through form factors. Charmonium breakup due to scattering with light mesons is the primary impediment to continued propagation. Breakup rates introduce nontrivial temperature and momentum dependence into the J/ψ\psi spectral function.Comment: 6 Pages LaTeX, 3 postscript figures. Proceedings for Strangeness in Quark Matter 2003, Atlantic Beach, NC, March 12-17, 2003; minor corrections in version 2, to appear in J. Phys.

    A numerical investigation of a piezoelectric surface acoustic wave interaction with a one-dimensional channel

    Full text link
    We investigate the propagation of a piezoelectric surface acoustic wave (SAW) across a GaAs/AlX_XGa1X_{1-X}As heterostructure surface, on which there is fixed a metallic split-gate. Our method is based on a finite element formulation of the underlying equations of motion, and is performed in three-dimensions fully incorporating the geometry and material composition of the substrate and gates. We demonstrate attenuation of the SAW amplitude as a result of the presence of both mechanical and electrical gates on the surface. We show that the incorporation of a simple model for the screening by the two-dimensional electron gas (2DEG), results in a total electric potential modulation that suggests a mechanism for the capture and release of electrons by the SAW. Our simulations suggest the absence of any significant turbulence in the SAW motion which could hamper the operation of SAW based quantum devices of a more complex geometry.Comment: 8 pages, 8 figure

    Challenges of a simplified opt-out consent process in a neonatal randomised controlled trial: a qualitative study of parents’ and health professionals’ views and experiences

    Get PDF
    Background: More effective recruitment strategies like alternative approaches to consent are needed to facilitate adequately powered trials. WithHolding Enteral feeds Around Transfusion (WHEAT) was a multicentre, randomised, pilot trial that compared withholding and continuing feeds around transfusion. The primary clinical outcome was necrotising enterocolitis (NEC). The trial used simplified opt-out consent with concise parent information and no consent form. Objective: To explore the views and experiences of parents and health professionals on the acceptability and feasibility of opt-out consent in randomised comparative effectiveness trials. Methods: A qualitative, descriptive interview-based study nested within a randomised trial. Semi-structured interview transcripts were analysed using inductive thematic analysis. Setting: Eleven neonatal units in England. Participants: Eleven parents and ten health professionals with experience of simplified consent. Results: Five themes emerged: ‘Opt-out consent operationalised as verbal opt-in consent’, ‘Opt-out consent normalises participation while preserving parental choice’, ‘Opt-out consent as an ongoing process of informed choice’, ‘Consent without a consent form’ and ‘Choosing to opt out of a comparative effectiveness trial’, with two subthemes: ‘Wanting “normal care”’ and ‘A belief that feeding is better’. Conclusions: Introducing a novel form of consent proved challenging in practice. The principle of simplified, opt-out approach to consent was generally considered feasible and acceptable by health professionals for a neonatal comparative effectiveness trial. The priority for parents was having the right to decide about trial participation, and they did not see opt-out consent as undermining this. Describing a study as ‘opt-out’ can help to normalise participation and emphasise that parents can withdraw consent

    Aspects of meson properties in dense nuclear matter

    Get PDF
    We investigate the modification of meson spectral densities in dense nuclear matter at zero temperature. These effects are studied in a fully relativistic mean field model which goes beyond the linear density approximation and also includes baryon resonances. In particular, the role of N*(1520) and N*(1720) on the rho meson spectral density is highlighted. Even though the nucleon-nucleon loop and the nucleon-resonance loop contribute with the opposite sign, an overall reduction of rho meson mass is still observed at high density. Importantly, it is shown that the resonances cause substantial broadening of the rho meson spectral density in matter and also induces non-trivial momentum dependence. The spectral density of the a0 meson is also shown. We study the dispersion relations and collective oscillations induced by the rho meson propagation in nuclear matter together with the influence of the mixing of rho with the a0 meson. The relevant expression for the plasma frequency is also recovered analytically in the appropriate limit.Comment: 19 pages, 17 figure

    Possibilities for CO2 emission reduction using biomass in European integrated steel plants

    Get PDF
    Iron and steel plants producing steel via the blast furnace-basic oxygen furnace (BF-BOF) route constitute among the largest single point CO2 emitters within the European Union (EU). As the iron ore reduction process in the blast furnace is fully dependent on carbon mainly supplied by coal and coke, bioenergy is the only renewable that presents a possibility for their partial substitution. Using the BeWhere model, this work optimised the mobilization and use of biomass resources within the EU in order to identify the opportunities that bioenergy can bring to the 30 operating BF-BOF plants. The results demonstrate competition for the available biomass resources within existing industries and economically unappealing prices of the bio-based fuels. A carbon dioxide price of 60 € t−1 is required to substitute 20% of the CO2 emissions from the fossil fuels use, while a price of 140 € t−1 is needed to reach the maximum potential of 42%. The possibility to use organic wastes to produce hydrochar would not enhance the maximum emission reduction potential, but it would broaden the available feedstock during the low levels of substitution. The scope for bioenergy integration is different for each plant and so consideration of its deployment should be treated individually. Therefore, the EU-ETS (Emission Trading System) may not be the best policy tool for bioenergy as an emission reduction strategy for the iron and steel industry, as it does not differentiate between the opportunities across the different steel plants and creates additional costs for the already struggling European steel industry
    corecore