87 research outputs found

    Vortex Plastic Flow, B(x,y,H(t)),M(H(t)),Jc(B(t))B(x,y,H(t)), M(H(t)), J_c(B(t)), Deep in the Bose Glass and Mott-Insulator Regimes

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    We present simulations of flux-gradient-driven superconducting vortices interacting with strong columnar pinning defects as an external field H(t)H(t) is quasi-statically swept from zero through a matching field BÏ•B_{\phi}. We analyze several measurable quantities, including the local flux density B(x,y,H(t)) B(x,y,H(t)), magnetization M(H(t))M(H(t)), critical current Jc(B(t))J_{c}(B(t)), and the individual vortex flow paths. We find a significant change in the behavior of these quantities as the local flux density crosses BÏ•B_{\phi}, and quantify it for many microscopic pinning parameters. Further, we find that for a given pin density Jc(B)J_c(B) can be enhanced by maximizing the distance between the pins for B<BÏ• B < B_{\phi} .Comment: 4 pages, 4 PostScript Figure

    Equilibrium and stability of neutrino lumps as TOV solutions

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    We report about stability conditions for static, spherically symmetric objects that share the essential features of mass varying neutrinos in cosmological scenarios. Compact structures of particles with variable mass are held together preponderantly by an attractive force mediated by a background scalar field. Their corresponding conditions for equilibrium and stability are given in terms of the ratio between the total mass-energy and the spherical lump radius, M/RM/R. We show that the mass varying mechanism leading to lump formation can modify the cosmological predictions for the cosmological neutrino mass limits. Our study comprises Tolman-Oppenheimer-Volkoff solutions of relativistic objects with non-uniform energy densities. The results leave open some questions concerning stable regular solutions that, to an external observer, very closely reproduce the preliminary conditions to form Schwarzschild black holes.Comment: 20 pages, 5 figure

    Kaluza-Klein Cosmology With Modified Holographic Dark Energy

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    We investigate the compact Kaluza-Klein cosmology in which modified holographic dark energy is interacting with dark matter. Using this scenario, we evaluate equation of state parameter as well as equation of evolution of the modified holographic dark energy. Further, it is shown that the generalized second law of thermodynamics holds without any constraint.Comment: 13 pages, accepted for publication in Gen. Relativ. Gravi

    The Similarity Hypothesis in General Relativity

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    Self-similar models are important in general relativity and other fundamental theories. In this paper we shall discuss the ``similarity hypothesis'', which asserts that under a variety of physical circumstances solutions of these theories will naturally evolve to a self-similar form. We will find there is good evidence for this in the context of both spatially homogenous and inhomogeneous cosmological models, although in some cases the self-similar model is only an intermediate attractor. There are also a wide variety of situations, including critical pheneomena, in which spherically symmetric models tend towards self-similarity. However, this does not happen in all cases and it is it is important to understand the prerequisites for the conjecture.Comment: to be submitted to Gen. Rel. Gra

    Measurements of the Ratios B(Ds+→ηℓ+ν)/B(Ds+→ϕℓ+ν){\cal B}(D_s^+\to \eta\ell^+\nu)/{\cal B}(D_s^+\to \phi\ell^+\nu) and B(Ds+→η′ℓ+ν)/B(Ds+→ϕℓ+ν){\cal B}(D_s^+\to \eta'\ell^+\nu)/{\cal B}(D_s^+\to \phi\ell^+\nu)

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    Using the CLEO~II detector we measure B(Ds+→ηe+ν)/B(Ds+→ϕe+ν)=1.24±0.12±0.15{\cal B}(D_s^+\to \eta e^+\nu)/{\cal B}(D_s^+\to \phi e^+\nu) =1.24\pm0.12\pm0.15, B(Ds+→η′e+ν)/B(Ds+→ϕe+ν)=0.43±0.11±0.07{\cal B}(D_s^+\to \eta' e^+\nu)/{\cal B}(D_s^+\to \phi e^+\nu) =0.43\pm0.11\pm0.07 and B(Ds+→η′e+ν)/B(Ds+→ηe+ν)=0.35±0.09±0.07{\cal B}(D_s^+\to \eta' e^+\nu)/{\cal B}(D_s^+\to \eta e^+\nu) =0.35\pm0.09\pm0.07. We find the vector to pseudoscalar ratio, B(Ds+→ϕe+ν)/B(Ds+→(η+η′)e+ν)=0.60±0.06±0.06{\cal B}(D_s^+\to \phi e^+\nu)/{\cal B}(D_s^+\to (\eta+\eta') e^+\nu) =0.60\pm0.06\pm0.06, which is similar to the ratio found in non strange DD decays.Comment: 11 page uuencoded postscript file, postscript file also available through http://w4.lns.cornell.edu/public/CLN

    Whole-genome sequencing reveals host factors underlying critical COVID-19

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    Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care1 or hospitalization2,3,4 after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes—including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)—in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease

    First record of Ligula intestinalis from stone loach

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    The cestode Ligula intestinalis was recorded for the first time from stone loach Barbatula barbatulus. Details regarding their site of capture and intensity of infection are provided

    Ground disposal of oil shale wastes: a review with an indexed annotated bibliography through 1976

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    This review covers the available literature concerning ground-disposed wastes and effluents of a potential oil shale industry. Ground disposal has been proposed for essentially all of the solid and liquid wastes produced (Pfeffer, 1974). Since an oil shale industry is not actually in operation, the review is anticipatory in nature. The section, Oil Shale Technology, provides essential background for interpreting the literature on potential shale oil wastes and the topics are treated more completely in the section entitled Environmental Aspects of the Potential Disposal of Oil Shale Wastes to Ground. The first section of the annotated bibliography cites literature concerning potential oil shale wastes and the second section cites literature concerning oil shale technology. Each section contains references arranged historically by year. An index is provided
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