1,033 research outputs found

    Dry heat effects on survival of indigenous soil particle microflora and particle viability studies of Kennedy Space Center soil

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    Research efforts were concentrated on attempts to obtain data concerning the dry heat resistance of particle microflora in Kennedy Space Center soil samples. The in situ dry heat resistance profiles at selected temperatures for the aggregate microflora on soil particles of certain size ranges were determined. Viability profiles of older soil samples were compared with more recently stored soil samples. The effect of increased particle numbers on viability profiles after dry heat treatment was investigated. These soil particle viability data for various temperatures and times provide information on the soil microflora response to heat treatment and are useful in making selections for spacecraft sterilization cycles

    Logics, rhetoric and 'the blob': populist logic in the Conservative reforms to English schooling

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    A lot has been written about the lasting implications of the Conservative reforms to English schooling, particularly changes made by Michael Gove as Education Secretary (2010–2014). There is a lot less work, however, on studying the role that language, strategy and the broader political framework played in the process of instituting and winning consent for these reforms. Studying these factors is important for ensuring that any changes to education and schooling are not read in isolation from their political context. Speeches particularly capture moments where intellectual and strategic political traditions meet, helping us to form a richer understanding of the motives behind specific reform goals and where they fit into a political landscape. This article analyses speeches and policy documents from prominent politicians who led the Conservative education agenda between 2010–2014 to illustrate how politicians mobilised a deliberate populist strategy and argumentation to achieve specific educational goals, but which have had broader social and political implications. Concepts from interpretive political studies are used to develop a case analysis of changes to teacher training provision and curriculum reform, illustrating how politicians constructed a frontier between ‘the people’ (commonly teachers or parents) and an illegitimate ‘elite’ (an educational establishment) that opposed change. This anti‐elite populist rhetoric, arguably first tested in the Department for Education, has now become instituted more widely in our current British politics

    Nuclear shape dependence of Gamow-Teller distributions in neutron-deficient Pb isotopes

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    We study Gamow-Teller strength distributions in the neutron-deficient even isotopes (184-194)Pb in a search for signatures of deformation. The microscopic formalism used is based on a deformed quasiparticle random phase approximation (QRPA) approach, which involves a self-consistent quasiparticle deformed Skyrme Hartree-Fock (HF) basis and residual spin-isospin forces in both the particle-hole and particle-particle channels. By analyzing the sensitivity of the Gamow-Teller strength distributions to the various ingredients in the formalism, we conclude that the beta-decay of these isotopes could be a useful tool to look for fingerprints of nuclear deformation.Comment: 20 pages, 11 figures. To be published in Physical Review

    Solar Neutrinos from CNO Electron Capture

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    The neutrino flux from the sun is predicted to have a CNO-cycle contribution as well as the known pp-chain component. Previously, only the fluxes from beta+ decays of 13N, 15O, and 17F have been calculated in detail. Another neutrino component that has not been widely considered is electron capture on these nuclei. We calculate the number of interactions in several solar neutrino detectors due to neutrinos from electron capture on 13N, 15O, and 17F, within the context of the Standard Solar Model. We also discuss possible non-standard models where the CNO flux is increased.Comment: 4 pages, 1 figure, submitted to Phys. Rev. C; v2 has minor changes including integration over solar volume and addition of missing reference to previous continuum electron capture calculation; v3 has minor changes including addition of references and the correction of a small (about 1%) numerical error in the table

    Convergent evolution of an ant-plant mutualism across plant families, continents and time

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    Questions: How often has dispersal of seeds by ants evolved in monocots and is the timing of origins associated with changes in the ant community or instead with the rise of forests? Are patterns in the origin of elaiosomes (the trait associated with the dispersal of seeds by ants) through time similar to those for the origins of fleshy fruits? Data studied: We estimate the timing of the origin of elaiosomes and fleshy fruits respectivelyby mapping seed morphology onto a recent phylogeny based on ndhF sequence data forthe monocots (Givnish et al., 2005). For comparison, we use fossil data on ant relativeabundance through time and phylogenetic data for the timing of the origin of seed-dispersing ant lineages. Search method: We mapped origins of both elaiosomes and fleshy fruits onto the phylogenyusing parsimony in the program Mesquite (Maddison and Maddison, 2005). We analysed therelationship between ant relative abundances, the number of origins of seed-dispersing ants, and the rate of origination of elaiosomes using randomization-based Monte Carlo regression in the program R (Cliff and Ord, 1981). Using the program Discrete (Pagel, 2006), we test whether fleshy fruits or elaiosomes and shaded forest understoreys show correlated evolution.Conclusions: Morphological features for the dispersal of seeds by ants (myrmecochory) have evolved at least twenty times within the monocots. Origins of myrmecochory are not associated with the rise of forests during the Cretaceous or with subsequent transitions of plant lineages into closed canopy habitats, nor are they contemporaneous with the origins of fleshy fruits. Instead, the origins of myrmecochory are closely associated with the rise in relative abundanceof ants (proportion of all individual insects in fossils) towards the end of the Eocene and more recently

    ‘They Called Them Communists Then 
 What D'You Call ‘Em Now? 
 Insurgents?’. Narratives of British Military Expatriates in the Context of the New Imperialism

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    This paper addresses the question of the extent to which the colonial past provides material for contemporary actors' understanding of difference. The research from which the paper is drawn involved interview and ethnographic work in three largely white working-class estates in an English provincial city. For this paper we focus on ten life-history interviews with older participants who had spent some time abroad in the British military. Our analysis adopts a postcolonial framework because research participants' current constructions of an amorphous 'Other' (labelled variously as black people, immigrants, foreigners, asylum-seekers or Muslims) reveal strong continuities with discourses deployed by the same individuals to narrate their past experiences of living and working as either military expatriates or spouses during British colonial rule. Theoretically, the paper engages with the work of Frantz Fanon and Edward Said. In keeping with a postcolonial approach, we work against essentialised notions of identity based on 'race' or class. Although we establish continuity between white working-class military emigration in the past and contemporary racialised discourses, we argue that the latter are not class-specific, being as much the creations of the middle-class media and political elite

    Illness Labels and Social Distance

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    The authors examine a key proposition in the modified labeling theory—that a psychiatric label increases vulnerability to negative evaluation and social rejection—using an experimental design wherein female participants interact with a female teammate over a computer. The authors also evaluate a hypothesis derived from the disease-avoidance account of disgust by examining this same process for a nonpsychiatric illness: food poisoning. In addition, they introduce a composite measure of social distance behavior that is easy to implement in a laboratory experiment. The authors find, as predicted, that women seek greater social distance from teammates with a history of psychiatric or food poisoning hospitalization than they do from teammates with no hospitalization history. But, contrary to predictions, a teammate’s hospitalization history does not affect participants’ ratings of her likability. The results also do not vary significantly by psychiatric diagnosis (depression vs. schizophrenia), suggesting that the stigma of depression may be just as strong as the stigma of schizophrenia when information about symptoms is not available. The authors discuss the implications of these findings for the modified labeling theory of mental illness and for the literature on disgust and stigma. They also outline avenues for future research.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

    beta-decay in neutron-deficient Hg, Pb, and Po isotopes

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    The effect of nuclear deformation on the energy distributions of the Gamow-Teller strength is studied in neutron-deficient Hg, Pb, and Po even isotopes. The theoretical framework is based on a self-consistent deformed Skyrme Hartree-Fock mean field with pairing correlations between like nucleons in BCS approximation and residual spin-isospin interactions treated in the proton-neutron quasiparticle random phase approximation. After a systematic study of the Gamow-Teller strength distributions in the low excitation energy region, relevant for beta-decay, we have identified the best candidates to look for deformation signatures in their beta-decay patterns. beta+ half-lives and total Gamow-Teller strengths B(GT+) and B(GT-) are analyzed as well.Comment: 18 pages, 7 figures, to appear in Phys. Rev.

    Half-lives of rp-process waiting point nuclei

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    We give results of microscopic calculations for the half-lives of various proton-rich nuclei in the mass region A=60-90, which are involved in the astrophysical rp-process, and which are needed as input parameters of numerical simulations in Nuclear Astrophysics. The microscopic formalism consists of a deformed QRPA approach that involves a selfconsistent quasiparticle deformed Skyrme Hartree-Fock basis and residual spin-isospin separable forces in both the particle-hole and particle-particle channels. The strength of the particle-hole residual interaction is chosen to be consistent with the Skyrme effective force and mean field basis, while that of the particle-particle is globally fixed to 0.07 MeV after a judicious choice from comparison to experimental half-lives. We study and discuss the sensitivity of the half-lives to deformation and residual interactions.Comment: 8 pages, 4 figures, to be published in Eur. Phys. J.
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