392 research outputs found

    Nonlinear dynamo in a short Taylor-Couette setup

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    It is numerically demonstrated by means of a magnetohydrodynamics code that a short Taylor-Couette setup with a body force can sustain dynamo action. The magnetic threshold is comparable to what is usually obtained in spherical geometries. The linear dynamo is characterized by a rotating equatorial dipole. The nonlinear regime is characterized by fluctuating kinetic and magnetic energies and a tilted dipole whose axial component exhibits aperiodic reversals during the time evolution. These numerical evidences of dynamo action in a short Taylor-Couette setup may be useful for developing an experimental device

    Direct amplification of nodD from community DNA reveals the genetic diversity of Rhizobium leguminosarum in soil

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    Sequences of nodD, a gene found only in rhizobia, were amplified from total community DNA isolated from a pasture soil. The polymerase chain reaction (PCR) primers used, Y5 and Y6, match nodD from Rhizobium leguminosarum biovar trifolii, R. leguminosarum biovar viciae and Sinorhizobium meliloti. The PCR product was cloned and yielded 68 clones that were identified by restriction pattern as derived from biovar trifolii [11 restriction fragment length polymorphism (RFLP) types] and 15 clones identified as viciae (seven RFLP types). These identifications were confirmed by sequencing. There were no clones related to S. meliloti nodD. For comparison, 122 strains were isolated from nodules of white clover (Trifolium repens) growing at the field site, and 134 from nodules on trap plants of T. repens inoculated with the soil. The nodule isolates were of four nodD RFLP types, with 77% being of a single type. All four of these patterns were also found among the clones from soil DNA, and the same type was the most abundant, although it made up only 34% of the trifolii-like clones. We conclude that clover selects specific genotypes from the available soil population, and that R. leguminosarum biovar trifolii was approximately five times more abundant than biovar viciae in this pasture soil, whereas S. meliloti was rare

    Euler configurations and quasi-polynomial systems

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    In the Newtonian 3-body problem, for any choice of the three masses, there are exactly three Euler configurations (also known as the three Euler points). In Helmholtz' problem of 3 point vortices in the plane, there are at most three collinear relative equilibria. The "at most three" part is common to both statements, but the respective arguments for it are usually so different that one could think of a casual coincidence. By proving a statement on a quasi-polynomial system, we show that the "at most three" holds in a general context which includes both cases. We indicate some hard conjectures about the configurations of relative equilibrium and suggest they could be attacked within the quasi-polynomial framework.Comment: 21 pages, 6 figure

    Responsabilidad médica presunta. Clínica Forense 2012

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    Introducción: La responsabilidad profesional médica presunta, por denuncias en personas, con sospecha de error médico, requiere de calificación pericial especializada. Objetivos: Establecer la incidencia de la responsabilidad profesional médica presunta, por denuncias en personas, con sospecha de error médico en la clínica forense. Diseño: Cuantitativo, observacional, transversal. Institución: Instituto Medicina Legal, Ministerio Público, e Instituto de Patología, UNMSM. Material de estudio: Informes periciales de reconocimientos medico legales en historias clínicas. Intervenciones: Médico legales por denuncia jurisdiccional, por sospecha de responsabilidad. Principales medidas de resultados: Medidas de tendencia central porcentual. Resultados: Se analizó 142 expedientes, de enero a junio de 2012, encontrando sexo femenino 61,3% (87), masculino 38,7% (55), menores de edad 10,6% (15), 18 a 50 años 23,9% (34), >51 años 65,5% (93), con incremento en enero, abril. Conclusiones: El incremento de denuncias se incrementó con la edad y la mayor incidencia correspondió a aquellos pacientes mayores de 60 años, que están comprendidos en la tercera edad y requieren una atención especial y de cuidado

    Metastatic Renal Cell Carcinoma Rapidly Progressive to Sunitinib: What to Do Next?

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    Background: From 10% to 26% of patients with metastatic renal cell carcinoma (mRCC) experience rapidly progressive disease (PD) on treatment with sunitinib. Objective: To investigate the benefit of subsequent treatment with another tyrosine kinase inhibitor (TKI) or a mammalian target of rapamycin (mTOR) inhibitor in such primary refractory patients. Design, setting, and participants: A total of 150 mRCC patients with rapidly PD on first- line sunitinib (within two cycles, n = 93, or four cycles, n = 57) were identified: median age 59 yr; nephrectomy 86%; histological subtypes: clear cell (77.8%), papillary (14%), and sarco- matoid features (18%); according to the Memorial Sloan-Kettering Cancer Center and French classifications: good risk (11% and 7%, respectively), intermediate (68% and 63%, respectively), and poor (21% and 29%, respectively). Outcome measurements and statistical analysis: Data were retrospectively collected by a questionnaire from 19 European oncology centers between March 2005 and March 2011. Pro- gression-free survival (PFS) and overall survival (OS) were calculated (Kaplan-Meier method). Results and limitations: Median OS from the start of first-line treatment was 7.4 mo. Second-line treatment was administered to 86 (57%) patients (44 mTOR inhibitors: 23 ever- olimus and 21 temsirolimus; 39 TKIs alone or in combination; three chemotherapy). Second- line PFS was not significantly different between TKIs and mTOR inhibitors (2.0 vs 0.9 mo; p = 0.536). Median OS from the start of second-line treatment was 5.0 mo for mTOR inhibitors and 6.6 mo for TKIs (p = 0.15). Conclusions: Treatment with further TKIs or mTOR inhibitors for mRCC patients primarily refractory to first-line sunitinib in the observed time period achieved very minimal benefit, suggesting avoiding TKI rechallenge and possibly preferring alternative strategies, such as immune checkpoint inhibitors, after PD to a treatment line including a TKI in this setting. Patient summary: The present work collected data about 150 patients affected by meta- static renal cell carcinoma, who received one of the current standard of care as first-line treatment, namely, the antiangiogenic drug sunitinib, and experienced rapid worsening of the disease. We investigated and described the subsequent outcome of such patients treated with two different types of drug, administered as second-line therapy, to better understand the best strategy to adopt for patients who got no benefit from sunitinib and to describe the current therapeutic approach in such cases

    A comment on Scott's “Black Polygamous Family Formation”

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    This brief article takes a critical look at Joseph W. Scott's article “Black Polygamous Family Formation.” While Scott's research is seen as helpful, several problems in his treatment of plural mating and marriage arrangements among Black Americans are discussed. Major conceptual problems are created by Scott's use (or misuse) of the concept “polygyny.” Significant methodological problems are also posed by his sampling approach, operationalization of concepts, and analytic strategies. Studies such as Scott's are of optimal value when their exploratory nature, and consequent limitation, are clearly acknowledged.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44661/1/10834_2005_Article_BF01082935.pd

    Witnessing loss in the everyday: community buildings in Austerity Britain

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    This article is concerned with what happens to precarious community buildings in times of austerity. It responds to a landscape of capitalist realism, in which instrumental, economic forms of value are mobilised to justify the closure of ordinary buildings whose survival is not identified as a political priority. We focus on two London cases of a library and an elderly day centre under threat of closure, and trace how grammars of austerity rendered these buildings substitutable. Considering how abstract sociological conceptions of value/s can struggle to break into the embedded common sense of austerity, we explore how ethnographic practices of collaboration and attentiveness can help amplify alternative expressions of the meanings of these buildings for their communities. Enacting a form of ethnographic witnessing, which learns from Wittgenstein, we highlight the creative, vernacular registers and gestures of library users and day centre members, and we show how these were anchored in the buildings themselves. In this way, we supplement noisier, more hyperbolic accounts of the violence of austerity by amplifying quotidian responses, which express how ordinary buildings and the forms of life they sustain, matter

    The nuclear receptors of Biomphalaria glabrata and Lottia gigantea: Implications for developing new model organisms

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    © 2015 Kaur et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are creditedNuclear receptors (NRs) are transcription regulators involved in an array of diverse physiological functions including key roles in endocrine and metabolic function. The aim of this study was to identify nuclear receptors in the fully sequenced genome of the gastropod snail, Biomphalaria glabrata, intermediate host for Schistosoma mansoni and compare these to known vertebrate NRs, with a view to assessing the snail's potential as a invertebrate model organism for endocrine function, both as a prospective new test organism and to elucidate the fundamental genetic and mechanistic causes of disease. For comparative purposes, the genome of a second gastropod, the owl limpet, Lottia gigantea was also investigated for nuclear receptors. Thirty-nine and thirty-three putative NRs were identified from the B. glabrata and L. gigantea genomes respectively, based on the presence of a conserved DNA-binding domain and/or ligand-binding domain. Nuclear receptor transcript expression was confirmed and sequences were subjected to a comparative phylogenetic analysis, which demonstrated that these molluscs have representatives of all the major NR subfamilies (1-6). Many of the identified NRs are conserved between vertebrates and invertebrates, however differences exist, most notably, the absence of receptors of Group 3C, which includes some of the vertebrate endocrine hormone targets. The mollusc genomes also contain NR homologues that are present in insects and nematodes but not in vertebrates, such as Group 1J (HR48/DAF12/HR96). The identification of many shared receptors between humans and molluscs indicates the potential for molluscs as model organisms; however the absence of several steroid hormone receptors indicates snail endocrine systems are fundamentally different.The National Centre for the Replacement, Refinement and Reduction of Animals in Research, Grant Ref:G0900802 to CSJ, LRN, SJ & EJR [www.nc3rs.org.uk]

    Monitored Indoor Environmental Quality of a Mass Timber Office Building: A Case Study

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    A broad range of building performance monitoring, sampling, and evaluation was conducted periodically after construction and spanning more than a year, for an occupied office building constructed using mass timber elements such as cross-laminated timber (CLT) floor and roof panels, as well as glue-laminated timber (GLT) beams and columns. This case study contributes research on monitoring indoor environmental quality in buildings, describing one of the few studies of an occupied mass timber building, and analyzing data in three areas that impact occupant experience: indoor air quality, bacterial community composition, and floor vibration. As a whole, the building was found to perform well. Volatile organic compounds (VOCs), including formaldehyde, were analyzed using multiple methods. Formaldehyde was found to be present in the building, though levels were below most recommended exposure limits. The source of formaldehyde was not able to be identified in this study. The richness of the bacterial community was affected by the height of sampling with respect to the floor, and richness and composition was aected by the location within the building. Floor vibration was observed to be below recognized human comfort thresholds
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