1,238 research outputs found

    A Thinking Person\u27s Guide to Entry/Exit Deregulation in the Airline Industry

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    Sex-Linked Behavior: Evolution, Stability, and Variability

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    This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.Common understanding of human sex-linked behaviors is that proximal mechanisms of genetic and hormonal sex, ultimately shaped by the differential reproductive challenges of ancestral males and females, act on the brain to transfer sex-linked predispositions across generations. Here, we extend the debate on the role of nature and nurture in the development of traits in the lifetime of an individual, to their role in the cross-generation transfer of traits. Advances in evolutionary theory that posit the environment as a source of trans-generational stability, and new understanding of sex effects on the brain, suggest that the cross-generation stability of sex-linked patterns of behavior are sometimes better explained in terms of inherited socioenvironmental conditions, with biological sex fostering intrageneration variability.C.F. is grateful for the support of a Women’s Leadership Institute Australia Fellowship. J.D’s research leading to this article has received funding from the European Research Council under the European Union’s Seventh Framework Programme (FP7/2007-2013)/ERC Grant Agreement 324186. D.J. acknowledges the support of the Israel Science Foundation (grant No. 217/16)

    High-resolution Elemental Mapping of the Lunar Surface

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    New instruments and missions are being proposed to study the lunar surface as a result of the resurgence of interest in returning to the Moon. One instrument recently proposed is similar in concept to the x-ray fluorescence detectors flown on Apollo, but utilizes fluorescence from the L- and M-shells rather than the K-shell. This soft X-Ray Flourescence Imager (XRFI) is discussed

    Decision and Discovery in Defining “Disease”

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    This version (May 17, 2005) was published in its final form as: Schwartz PH. Decision and discovery in defining 'disease'. In: Kincaid H, McKitrick J, editors. Establishing medical reality: essays in the metaphysics and epistemology of biomedical science. Dordrecht: Springer; 2007. p. 47-63. http://dx.doi.org/10.1007/1-4020-5216-2_5The debate over how to analyze the concept of disease has often centered on the question of whether to include a reference to values, in particular the ‘disvalue’of diseases, or whether to avoid such notions. ‘Normativists,’such as King ([1954], 1981) and Culver and Gert (1982) emphasize the undesirability of diseases, while ‘Naturalists,’ most prominently Christopher Boorse (1977, 1987, 1997), instead require just the presence of biological dysfunction. The debate between normativism and naturalism often deteriorates into stalemate, with each side able to point out significant problems with the other. It starts to look as if neither approach can work. In this paper, I argue that the standoff stems from deeply questionable assumptions that have been used to formulate the opposing positions and guide the debate. In the end, I propose an alternative set of guidelines that offer a more constructive way to devise and compare theories

    Conception et réalisation des capteurs hybrides photovoltaïque-thermiques sous vide ou avec lame d’air confinée

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    Cette étude fait l’analyse des performances thermiques et électriques de deux types de capteurs solaires hybrides photovoltaïque-thermiques à air intégrables en toitures des bâtiments. Pour ces capteurs hybrides, les cellules PV sont isolées soit avec une lame d’air confinée ou soit avec un gap vide. La modélisation des transferts de chaleur dans les systèmes est effectuée en 2D et en régime transitoire, suivant l’approche nodale. Le code numérique développé a été validé et a permis d’analyser les comportements thermiques ainsi que les efficacités thermique et électrique des capteurs. L’optimisation des paramètres fonctionnels est ensuite effectuée et présentée.Mots-clés: énergie solaire, cellules photovoltaïques, capteurs solaires hybrides (PV/T), transferts thermiques. Conception and realization of hybrid photovoltaic thermal collectors with empty gap or with enclosed air cavityThe present work reports thermal and electrical efficiencies for two solar hybrid photovoltaic-thermal air collectors integrated into the roof of the buildings. In these hybrid collectors, the PV cells are insulated with the enclosed air film or with the empty gap cavity. The unsteady and two-dimensional heat transfer equations are proposed and these equations are discretized using nodal method. The numerical model developed is validated. Then thermal and electrical efficiencies are analyzed for the collectors. The optimization of the characteristics parameters is studied in detail.Keywords: solar energy, photovoltaic cells, hybrid solar collector, heat transfer, nodal method

    Dipeptidyl Peptidase IV Inhibition With MK0431 Improves Islet Graft Survival in Diabetic NOD Mice Partially via T-Cell Modulation

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    OBJECTIVE—The endopeptidase dipeptidyl peptidase-IV (DPP-IV) has been shown to NH2-terminally truncate incretin hormones, glucose-dependent insulinotropic polypeptide, and glucagon-like peptide-1, thus ablating their ability to potentiate glucose-stimulated insulin secretion. Increasing the circulating levels of incretins through administration of DPP-IV inhibitors has therefore been introduced as a therapeutic approach for the treatment of type 2 diabetes. DPP-IV inhibitor treatment has also been shown to preserve islet mass in rodent models of type 1 diabetes. The current study was initiated to define the effects of the DPP-IV inhibitor sitagliptin (MK0431) on transplanted islet survival in nonobese diabetic (NOD) mice, an autoimmune type 1 diabetes model

    Symmetries of Electrostatic Interaction between DNA Molecules

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    We study a model for pair interaction UU of DNA molecules generated by the discrete dipole moments of base-pairs and the charges of phosphate groups, and find noncommutative group of eighth order S{\cal S} of symmetries that leave UU invariant. We classify the minima using group S{\cal S} and employ numerical methods for finding them. The minima may correspond to several cholesteric phases, as well as phases formed by cross-like conformations of molecules at an angle close to 90o\rm{90}^{o}, "snowflake phase". The results depend on the effective charge QQ of the phosphate group which can be modified by the polycations or the ions of metals. The snowflake phase could exist for QQ above the threshold QCQ_C. Below QCQ_C there could be several cholesteric phases. Close to QCQ_C the snowflake phase could change into the cholesteric one at constant distance between adjacent molecules.Comment: 13 pages, 4 figure
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