622 research outputs found

    Heavy quark free energies and screening at finite temperature and density

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    We study the free energies of heavy quarks calculated from Polyakov loop correlation functions in full 2-flavour QCD using the p4-improved staggered fermion action. A small but finite Baryon number density is included via Taylor expansion of the fermion determinant in the Baryo-chemical potential mu. For temperatures above Tc we extract Debye screening masses from the large distance behaviour of the free energies and compare their mu-dependence to perturbative results.Comment: 6 pages, Presented at 23rd International Symposium on Lattice Field Theory (Lattice 2005), Trinity College, Dublin, Ireland, 25-30 Jul 200

    Assessment of pulmonary antibodies with induced sputum and bronchoalveolar lavage induced by nasal vaccination against Pseudomonas aeruginosa: a clinical phase I/II study

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    <p>Abstract</p> <p>Background</p> <p>Vaccination against <it>Pseudomonas aeruginosa </it>is a desirable albeit challenging strategy for prevention of airway infection in patients with cystic fibrosis. We assessed the immunogenicity of a nasal vaccine based on the outer membrane proteins F and I from <it>Pseudomonas aeruginosa </it>in the lower airways in a phase I/II clinical trial.</p> <p>Methods</p> <p>N = 12 healthy volunteers received 2 nasal vaccinations with an OprF-OprI gel as a primary and a systemic (n = 6) or a nasal booster vaccination (n = 6). Antibodies were assessed in induced sputum (IS), bronchoalveolar lavage (BAL), and in serum.</p> <p>Results</p> <p>OprF-OprI-specific IgG and IgA antibodies were found in both BAL and IS at comparable rates, but differed in the predominant isotype. IgA antibodies in IS did not correlate to the respective serum levels. Pulmonary antibodies were detectable in all vaccinees even 1 year after the vaccination. The systemic booster group had higher IgG levels in serum. However, the nasal booster group had the better long-term response with bronchial antibodies of both isotypes.</p> <p>Conclusion</p> <p>The nasal OprF-OprI-vaccine induces a lasting antibody response at both, systemic and airway mucosal site. IS is a feasible method to non-invasively assess bronchial antibodies. A further optimization of the vaccination schedule is warranted.</p

    Inspiring Farmers For Healthy Farming

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    "The health and nutritional value of agricultural food products is strongly linked to, and inherently dependent on the production process and farm system. However, there are currently only limited options for transferring and measuring farm-health principles at farm level (Vieweger and Döring, 2015). In our previous work we have shown how organic farmers have developed their own strategies and philosophies for running healthy farming systems and increase the health of soils, plants, animals and humans. Such tacit farmer knowledge and awareness of a holistic systems-approach to health in food production can contribute crucial information and practical understanding for food system sustainability. The current project builds on these earlier findings, using participatory multi-actor approaches to collaborate with the established international network. The farmer groups in Germany, Austria and the UK aimed to 1) conceptualize health criteria on farms, such as ‘Is a nutrient or humus balance calculated?‘, ‘How much time is spent for observation and reflection?’, ‘Are regionally adapted breeds and varieties used?’; and 2) develop a concept for farmer-to-farmer learning, defining most appropriate conditions and methodologies for the multiplication of this knowledge. With a co-learning approach, we aim to allow a flexible integration of farmer knowledge and experience, thereby inspiring farmers to reflect on the potential ways they can improve health in their system, and further develop their individual methods over time; this approach also aims to help research identify general drivers of farm health.

    On the background in the γp→ω(π0γ)p\gamma p \to \omega(\pi^0\gamma) p reaction and mixed event simulation

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    In this paper we evaluate sources of background for the γp→ωp\gamma p \to \omega p, with the ω\omega detected through its π0γ\pi^0 \gamma decay channel, to compare with the experiment carried out at ELSA. We find background from γp→π0π0p\gamma p \to \pi^0 \pi^0 p followed by decay of a π0\pi^0 into two γ\gamma, recombining one π0\pi^0 and one γ\gamma, and from the γp→π0ηp\gamma p \to \pi^0 \eta p reaction with subsequent decay of the η\eta into two photons. This background accounts for the data at π0γ\pi^0 \gamma invariant masses beyond 700 MeV, but strength is missing at lower invariant masses which was attributed to photon misidentification events, which we simulate to get a good reproduction of the experimental background. Once this is done, we perform an event mixing simulation to reproduce the calculated background and we find that the method provides a good description of the background at low π0γ\pi^0 \gamma invariant masses but fakes the background at high invariant masses, making background events at low invariant masses, which are due to γ\gamma misidentification events, responsible for the background at high invariant masses which is due to the γp→π0π0p\gamma p \to \pi^0 \pi^0 p and γp→π0ηp\gamma p \to \pi^0 \eta p reactions.Comment: 10 pages, 5 figure

    Quantum Histories and Quantum Gravity

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    This paper reviews the histories approach to quantum mechanics. This discussion is then applied to theories of quantum gravity. It is argued that some of the quantum histories must approximate (in a suitable sense) to classical histories, if the correct classical regime is to be recovered. This observation has significance for the formulation of new theories (such as quantum gravity theories) as it puts a constraint on the kinematics, if the quantum/classical correspondence principle is to be preserved. Consequences for quantum gravity, particularly for Lorentz symmetry and the idea of "emergent geometry", are discussed.Comment: 35 pages (29 pages main body), two figure

    The DNDN, πΣc\pi \Sigma_c interaction in finite volume and the Λc(2595)\Lambda_c(2595) resonance

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    In this work the interaction of the coupled channels DNDN and πΣc\pi \Sigma_c in an SU(4) extrapolation of the chiral unitary theory, where the Λc(2595)\Lambda_c(2595) resonance appears as dynamically generated from that interaction, is extended to produce results in finite volume. Energy levels in the finite box are evaluated and, assuming that they would correspond to lattice results, the inverse problem of determining the phase shifts in the infinite volume from the lattice results is solved. We observe that it is possible to obtain accurate πΣc\pi \Sigma_c phase shifts and the position of the Λc(2595)\Lambda_c(2595) resonance, but it requires the explicit consideration of the two coupled channels. We also observe that some of the energy levels in the box are attached to the closed DNDN channel, such that their use to induce the πΣc\pi \Sigma_c phase shifts via L\"uscher's formula leads to incorrect results.Comment: 10 pages, 13 figures, accepted for publication in Eur. Phys. J.
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