82 research outputs found

    The hard X-ray and Ti-44 emission of Cas A

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    We present an analysis of the BeppoSAX high X-ray energy spectrum of the supernova remnant Cassiopeia A with an observation time of 83 ks. We measure a flux upper limit of 4.1E-5 ph/cm^2/s (99.7% confidence) of the nuclear decay lines of Ti-44 at 68 keV and 78 keV that is lower and inconsistent with the flux of an accompanying line at 1157 keV measured by CGRO's Comptel. However, if the underlying X-ray continuum is lower, because the spectrum is steepening, the actual Ti-44 flux may be higher and consistent with the Comptel result, although the measured flux of (2.9 +/- 1.0)E-5 ph/cm^2/s under this assumption is still lower than the flux measured by Comptel.Comment: ; JVs present address: AIP, Potsdam ([email protected]). To be published in Advances of Space Research (proc. of the Cospar Conference, Nagoya, 1998). 6 pages, 3 figure

    Antineutrinos from Earth: A reference model and its uncertainties

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    We predict geoneutrino fluxes in a reference model based on a detailed description of Earth's crust and mantle and using the best available information on the abundances of uranium, thorium, and potassium inside Earth's layers. We estimate the uncertainties of fluxes corresponding to the uncertainties of the element abundances. In addition to distance integrated fluxes, we also provide the differential fluxes as a function of distance from several sites of experimental interest. Event yields at several locations are estimated and their dependence on the neutrino oscillation parameters is discussed. At Kamioka we predict N(U+Th)=35 +- 6 events for 10^{32} proton yr and 100% efficiency assuming sin^2(2theta)=0.863 and delta m^2 = 7.3 X 10^{-5} eV^2. The maximal prediction is 55 events, obtained in a model with fully radiogenic production of the terrestrial heat flow.Comment: 24 pages, ReVTeX4, plus 7 postscript figures; minor formal changes to match version to be published in PR

    Initial genomic characterization of Italian, Egyptian and Pakistani goat breeds

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    Selection and breeding practices in goats have differed greatly among countries and populations. These processes, together with natural selection and regional drift, have shaped the phenotypic variability of goat breeds (Kim et al., 2015). The availability of improved genomic analysis tools for this species may provide useful information on the history of selection, adaptation and differentiation of goats from different areas of the world, that can be evaluated by the study of gene frequencies and length of the Runs of Homozigosity (contiguous length of homozygous genotypes, ROH; Purfield et al., 2012). In current study, we examined using a goat medium density SNP chip animals from three different countries: Egypt (with lack of selection scheme), Italy (with several standardized breeds; Nicoloso et al., 2015) and Pakistan (with several breeds showing peculiar phenotypes) to produce a genomic landscape of goats breeds in these countries. A total of 1,123 animals of 39 different populations, and 48,895 SNP markers were analyzed. Genotypes were imputed on a country-based approach, and markers without known position in the genome were excluded from the analysis. MDS and ADMIXTURE plots confirmed the good differentiation among populations from the three countries. Runs of Homozygosity (ROH) were performed for each country and population allowed the detection of genomic regions with high homozygosity levels, common in at least two out of three sampling areas. These results provide new insights into goat genome structure within and among breeds and countries. The detection of conserved regions with different lengths may explain recent selection strategies or adaptation to different, extreme environmental conditions. The research was funded by INNOVAGEN project. Support by Iowa State University and the Ensminger funds for AE and AT as well as support by the Fulbright Foundation for AE are gratefully acknowledged. Sampling from Pakistan was funded by PAK-USAID project

    The governance of social science and everyday epistemology

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    Research on the governance of publicly funded research does not recognize that social science and ‘science’ are distinct activities. Neither does it recognize that regulating research policy in purely science and technology terms has undesirable consequences for the social sciences – intended or otherwise. This paper seeks to correct these omissions and considers the governance of social science through the example of regulating ‘everyday epistemology’ at the science policy level. The British research council system is used in order to demonstrate how social science has been politically constructed as a legitimate enterprise for public funding. We find that social science is in fact regulated by non‐social scientists. The result is that social science, seen as a square peg, is forced into the round hole of natural scientific thinking. When this policy is translated into governance structures it creates a ‘slave social science’ and subverts the role of social science as social science

    [Avian cytogenetics goes functional] Third report on chicken genes and chromosomes 2015

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    High-density gridded libraries of large-insert clones using bacterial artificial chromosome (BAC) and other vectors are essential tools for genetic and genomic research in chicken and other avian species... Taken together, these studies demonstrate that applications of large-insert clones and BAC libraries derived from birds are, and will continue to be, effective tools to aid high-throughput and state-of-the-art genomic efforts and the important biological insight that arises from them

    Ultrafast coherent spectroscopy

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    Space as a Tool for Astrobiology: Review and Recommendations for Experimentations in Earth Orbit and Beyond

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