644 research outputs found

    Using evolutionary demography to link life history theory, quantitative genetics and population ecology

    Get PDF
    1. There is a growing number of empirical reports of environmental change simultaneously influencing population dynamics, life history and quantitative characters. We do not have a well-developed understanding of links between the dynamics of these quantities

    Determination of the Gamow-Teller Quenching Factor from Charge Exchange Reactions on 90Zr

    Full text link
    Double differential cross sections between 0-12 degrees were measured for the 90Zr(n,p) reaction at 293 MeV over a wide excitation energy range of 0-70 MeV. A multipole decomposition technique was applied to the present data as well as the previously obtained 90Zr(p,n) data to extract the Gamow-Teller (GT) component from the continuum. The GT quenching factor Q was derived by using the obtained total GT strengths. The result is Q=0.88+/-0.06 not including an overall normalization uncertainty in the GT unit cross section of 16%.Comment: 11 papes, 4 figures, submitted to Physics Letters B (accepted), gzipped tar file, changed content

    Trust, openness and continuity of care influence acceptance of antibiotics for children with respiratory tract infections: a four country qualitative study

    Get PDF
    Background. Clinician–parent interaction and health system influences on parental acceptance of prescribing decisions for children with respiratory tract infections (RTIs) may be important determinants of antibiotic use. Objective. To achieve a deeper understanding of parents’ acceptance, or otherwise, of clinicians’ antibiotic prescribing decisions for children with RTIs. Methods. Qualitative interviews with parents of child patients who had recently consulted in primary care with a RTI in four European countries, with a five-stage analytic framework approach (familiarization, developing a thematic framework from interview questions and emerging themes, indexing, charting and interpretation). Results. Fifty of 63 parents accepted clinicians’ management decisions, irrespective of antibiotic prescription. There were no notable differences between networks. Parents ascribed their acceptance to a trusting and open clinician–patient relationship, enhanced through continuity of care, in which parents felt able to express their views. There was a lack of congruence about antibiotics between parents and clinicians in 13 instances, mostly when parents disagreed about clinicians’ decision to prescribe (10 accounts) rather than objecting to withholding antibiotics (three accounts). All but one parent adhered to the prescribing decision, although some modified how the antibiotic was administered. Conclusions. Parents from contrasting countries indicated that continuity of care, open communication in consultations and clinician–patient trust was important in acceptance of management of RTI in their children and in motivating adherence. Interventions to promote appropriate antibiotic use in children should consider a focus on eliciting parents’ perspectives and promoting and building on continuity of care within a trusting clinician–patient relationship

    Young people today: news media, policy and youth justice

    Get PDF
    The new sociology of childhood sees children as competent social agents with important contributions to make. And yet the phase of childhood is fraught with tensions and contradictions. Public policies are required, not only to protect children, but also to control them and regulate their behaviour. For children and young people in the UK, youth justice has become increasingly punitive. At the same time, social policies have focused more on children's inclusion and participation. In this interplay of conflict and contradictions, the role the media play is critical in contributing to the moral panic about childhood and youth. In this article, we consider media representations of “antisocial” children and young people and how this belies a moral response to the nature of contemporary childhood. We conclude by considering how a rights-based approach might help redress the moralised politics of childhood representations in the media

    Light Hadron Masses from Lattice QCD

    Get PDF
    This article reviews lattice QCD results for the light hadron spectrum. We give an overview of different formulations of lattice QCD, with discussions on the fermion doubling problem and improvement programs. We summarize recent developments in algorithms and analysis techniques, that render calculations with light, dynamical quarks feasible on present day computer resources. Finally, we summarize spectrum results for ground state hadrons and resonances using various actions.Comment: 53 pages, 24 figures, one table; Rev.Mod.Phys. (published version); v2: corrected typ

    Damping mechanisms of the Delta resonance in nuclei

    Full text link
    The damping mechanisms of the Delta(1232) resonance in nuclei are studied by analyzing the quasi-free decay reactions 12C(pi+,pi+ p)11B and 12C(3He,t pi+ p)11B and the 2p emission reactions 12C(pi+,pp)10B and 12C(3He,t pp)10B. The coincidence cross sections are calculated within the framework of the isobar-hole model. It is found that the 2p emission process induced by the decay of the Delta resonance in the nucleus can be consistently described by a pi+rho+g' model for the Delta+N -> N+N decay interaction.Comment: 9 pages, 5 Postscript figures, uses RevTex, psfig.sty. Accepted by Physical Review

    Postcopulatory sexual selection

    Get PDF
    The female reproductive tract is where competition between the sperm of different males takes place, aided and abetted by the female herself. Intense postcopulatory sexual selection fosters inter-sexual conflict and drives rapid evolutionary change to generate a startling diversity of morphological, behavioural and physiological adaptations. We identify three main issues that should be resolved to advance our understanding of postcopulatory sexual selection. We need to determine the genetic basis of different male fertility traits and female traits that mediate sperm selection; identify the genes or genomic regions that control these traits; and establish the coevolutionary trajectory of sexes

    Measurement of the Generalized Forward Spin Polarizabilities of the Neutron

    Full text link
    The generalized forward spin polarizabilities γ0\gamma_0 and δLT\delta_{LT} of the neutron have been extracted for the first time in a Q2Q^2 range from 0.1 to 0.9 GeV2^2. Since γ0\gamma_0 is sensitive to nucleon resonances and δLT\delta_{LT} is insensitive to the Δ\Delta resonance, it is expected that the pair of forward spin polarizabilities should provide benchmark tests of the current understanding of the chiral dynamics of QCD. The new results on δLT\delta_{LT} show significant disagreement with Chiral Perturbation Theory calculations, while the data for γ0\gamma_0 at low Q2Q^2 are in good agreement with a next-to-lead order Relativistic Baryon Chiral Perturbation theory calculation. The data show good agreement with the phenomenological MAID model.Comment: 5 pages, 2 figures, corrected typo in author name, published in PR

    Risk factors for delayed presentation and referral of symptomatic cancer: Evidence for common cancers

    Get PDF
    Background:It has been suggested that the known poorer survival from cancer in the United Kingdom, compared with other European countries, can be attributed to more advanced cancer stage at presentation. There is, therefore, a need to understand the diagnostic process, and to ascertain the risk factors for increased time to presentation.Methods:We report the results from two worldwide systematic reviews of the literature on patient-mediated and practitioner-mediated delays, identifying the factors that may influence these.Results:Across cancer sites, non-recognition of symptom seriousness is the main patient-mediated factor resulting in increased time to presentation. There is strong evidence of an association between older age and patient delay for breast cancer, between lower socio-economic status and delay for upper gastrointestinal and urological cancers and between lower education level and delay for breast and colorectal cancers. Fear of cancer is a contributor to delayed presentation, while sanctioning of help seeking by others can be a powerful mediator of reduced time to presentation. For practitioner delay, ‘misdiagnosis’ occurring either through treating patients symptomatically or relating symptoms to a health problem other than cancer, was an important theme across cancer sites. For some cancers, this could also be linked to inadequate patient examination, use of inappropriate tests or failing to follow-up negative or inconclusive test results.Conclusion:Having sought help for potential cancer symptoms, it is therefore important that practitioners recognise these symptoms, and examine, investigate and refer appropriately. © 2009 Cancer Research UK All rights reserved
    corecore