156 research outputs found
A large class of non constant mean curvature solutions of the Einstein constraint equations on an asymptotically hyperbolic manifold
We construct solutions of the constraint equation with non constant mean
curvature on an asymptotically hyperbolic manifold by the conformal method. Our
approach consists in decreasing a certain exponent appearing in the equations,
constructing solutions of these sub-critical equations and then in letting the
exponent tend to its true value. We prove that the solutions of the
sub-critical equations remain bounded which yields solutions of the constraint
equation unless a certain limit equation admits a non-trivial solution.
Finally, we give conditions which ensure that the limit equation admits no
non-trivial solution.Comment: remark on the equivalence between the existence of a solution to the
Lichnerowicz equation and to the prescribed scalar curvature equation added,
reference [BPB09] added, to appear in Commun. Math. Phy
De novo identification of mammalian ciliary motility proteins using cryo-EM
Dynein-decorated doublet microtubules (DMTs) are critical components of the oscillatory molecular machine of cilia, the axoneme, and have luminal surfaces patterned periodically by microtubule inner proteins (MIPs). Here we present an atomic model of the 48-nm repeat of a mammalian DMT, derived from a cryoelectron microscopy (cryo-EM) map of the complex isolated from bovine respiratory cilia. The structure uncovers principles of doublet microtubule organization and features specific to vertebrate cilia, including previously unknown MIPs, a luminal bundle of tektin filaments, and a pentameric dynein-docking complex. We identify a mechanism for bridging 48- to 24-nm periodicity across the microtubule wall and show that loss of the proteins involved causes defective ciliary motility and laterality abnormalities in zebrafish and mice. Our structure identifies candidate genes for diagnosis of ciliopathies and provides a framework to understand their functions in driving ciliary motility
Adaptabilidade e estabilidade de populaçÔes de milho-pipoca relacionadas por ciclos de seleção
Os objetivos deste trabalho foram estimar os parĂąmetros de adaptabilidade e estabilidade em populaçÔes de milho-pipoca relacionadas por ciclos de seleção, inferir sobre a eficiĂȘncia dos mĂ©todos de seleção pelos quais as populaçÔes foram obtidas e avaliar os efeitos da seleção sobre os parĂąmetros de adaptabilidade e estabilidade. Vinte e cinco populaçÔes e trĂȘs testemunhas comerciais foram avaliadas em 14 ensaios realizados nos anos agrĂcolas de 2003/2004, 2004/2005, 2006/2007, 2008/2009 e 2009/2010, em sete locais. Utilizou-se o delineamento experimental de blocos completos ao acaso, com quatro repetiçÔes. Foram analisadas a capacidade de expansĂŁo, avaliada em forno de microondas e na pipocadora Metric Weight Volume Tester (MWVT), alĂ©m da produtividade de grĂŁos. Utilizou-se o mĂ©todo de adaptabilidade e estabilidade de Eberhart & Russell. Em geral, as populaçÔes base e melhoradas apresentaram previsibilidade de comportamento em resposta Ă s variaçÔes de ambiente. A seleção pode provocar mudanças nos padrĂ”es de adaptabilidade e estabilidade, e as diferentes estratĂ©gias de seleção empregadas na obtenção das populaçÔes apresentaram eficiĂȘncias semelhante
Management and treatment of children, young people and adults with systemic lupus erythematosus: British Society for Rheumatology guideline scope
The objective of this guideline is to provide up-to-date, evidence-based recommendations for the management of SLE that builds upon the existing treatment guideline for adults living with SLE published in 2017. This will incorporate advances in the assessment, diagnosis, monitoring, non-pharmacological and pharmacological management of SLE. General approaches to management as well as organ-specific treatment, including lupus nephritis and cutaneous lupus, will be covered. This will be the first guideline in SLE using a whole life course approach from childhood through adolescence and adulthood. The guideline will be developed with people with SLE as an important target audience in addition to healthcare professionals. It will include guidance related to emerging approved therapies and account for National Institute for Health and Care Excellence Technology Appraisals, National Health Service England clinical commissioning policies and national guidance relevant to SLE. The guideline will be developed using the methods and rigorous processes outlined in âCreating Clinical Guidelines: Our Protocolâ by the British Society for Rheumatology
Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo
Despite the growing number of binary black hole coalescences confidently observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include the effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that have already been identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total source-frame mass M > 70 Mâ) binaries covering eccentricities up to 0.3 at 15 Hz emitted gravitational-wave frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place a conservative upper limit for the merger rate density of high-mass binaries with eccentricities 0 < e †0.3 at 16.9 Gpcâ3 yrâ1 at the 90% confidence level
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