352 research outputs found

    A One-Parameter Family of Hamiltonian Structures for the KP Hierarchy and a Continuous Deformation of the Nonlinear \W_{\rm KP} Algebra

    Full text link
    The KP hierarchy is hamiltonian relative to a one-parameter family of Poisson structures obtained from a generalized Adler map in the space of formal pseudodifferential symbols with noninteger powers. The resulting \W-algebra is a one-parameter deformation of \W_{\rm KP} admitting a central extension for generic values of the parameter, reducing naturally to \W_n for special values of the parameter, and contracting to the centrally extended \W_{1+\infty}, \W_\infty and further truncations. In the classical limit, all algebras in the one-parameter family are equivalent and isomorphic to \w_{\rm KP}. The reduction induced by setting the spin-one field to zero yields a one-parameter deformation of \widehat{\W}_\infty which contracts to a new nonlinear algebra of the \W_\infty-type.Comment: 31 pages, compressed uuencoded .dvi file, BONN-HE-92/20, US-FT-7/92, KUL-TF-92/20. [version just replaced was truncated by some mailer

    VOCALS-CUpEx: the Chilean Upwelling Experiment

    Get PDF
    This is the publisher's version, also available electronically from http://www.atmos-chem-phys.net/11/2015/2011/acp-11-2015-2011.html.The VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx) was a major field experiment conducted in spring of 2008 off southern Peru and northern Chile, aimed at better understanding the coupled climate systems of the southeast Pacific. Because of logistical constrains, the coastal area around 30° S was not sampled during VOCALS-REx. This area not only marks the poleward edge of the subtropical stratocumulus cloud regime (thus acting as a source of transient disturbances) but is also one of the most active upwelling centers and source of surface ocean kinetic energy along the Chilean coast. To fill such an observational gap, a small, brief, but highly focused field experiment was conducted in late spring 2009 in the near-shore region around 30° S. The Chilean Upwelling Experiment (CUpEx) was endorsed by VOCALS as a regional component. CUpEx included long-term monitoring, an intensive two-week field campaign and off-shore research flights. Our goal was to obtain an atmospheric/oceanic dataset with enough temporal and spatial coverage to be able to document (a) the mean diurnal cycles of the lower-troposphere and upper-ocean in a region of complex topography and coastline geometry, and (b) the ocean-atmosphere response to the rapid changes in coastal winds from strong, upwelling-favorable equatorward flow (southerly winds) to downwelling-favorable poleward flow (northerly winds). In this paper we describe the measurement platforms and sampling strategy, and provide an observational overview, highlighting some key mean-state and transient features

    VOCALS-CUpEx: the Chilean Upwelling Experiment

    Get PDF
    This is the publisher's version, also available electronically from http://www.atmos-chem-phys.net/11/2015/2011/acp-11-2015-2011.html.The VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx) was a major field experiment conducted in spring of 2008 off southern Peru and northern Chile, aimed at better understanding the coupled climate systems of the southeast Pacific. Because of logistical constrains, the coastal area around 30° S was not sampled during VOCALS-REx. This area not only marks the poleward edge of the subtropical stratocumulus cloud regime (thus acting as a source of transient disturbances) but is also one of the most active upwelling centers and source of surface ocean kinetic energy along the Chilean coast. To fill such an observational gap, a small, brief, but highly focused field experiment was conducted in late spring 2009 in the near-shore region around 30° S. The Chilean Upwelling Experiment (CUpEx) was endorsed by VOCALS as a regional component. CUpEx included long-term monitoring, an intensive two-week field campaign and off-shore research flights. Our goal was to obtain an atmospheric/oceanic dataset with enough temporal and spatial coverage to be able to document (a) the mean diurnal cycles of the lower-troposphere and upper-ocean in a region of complex topography and coastline geometry, and (b) the ocean-atmosphere response to the rapid changes in coastal winds from strong, upwelling-favorable equatorward flow (southerly winds) to downwelling-favorable poleward flow (northerly winds). In this paper we describe the measurement platforms and sampling strategy, and provide an observational overview, highlighting some key mean-state and transient features

    Classical N=2 W-superalgebras From Superpseudodifferential Operators

    Full text link
    We study the supersymmetric Gelfand-Dickey algebras associated with the superpseudodifferential operators of positive as well as negative leading order. We show that, upon the usual constraint, these algebras contain the N=2 super Virasoro algebra as a subalgebra as long as the leading order is odd. The decompositions of the coefficient functions into N=1 primary fields are then obtained by covariantizing the superpseudodifferential operators. We discuss the problem of identifying N=2 supermultiplets and work out a couple of supermultiplets by explicit computations.Comment: 19 pages (Plain TeX), NHCU-HEP-94-1

    "Virus Identification for Monkeypox in Human Seminal Fluid Samples: A Systematic Review"

    Get PDF
    Public health officials around the world are extremely concerned about the global outbreak of monkeypox (MPX), which has been claimed to have originated in Africa. As a result, studies into the origins and reasons behind the outbreak’s rapid spread have been sped up. The goal of the current investigation is to determine whether the monkeypox virus (MPXV) is present in seminal fluid samples from MPX cases that have been verified. Up until 6 January 2023, PubMed, Scopus, Web of Science, Embase, and ScienceDirect databases were used to conduct a thorough evaluation of the literature. The search technique returned a total of 308 items. Fourteen studies reporting the presence of MPXV in the seminal fluid of MPX-confirmed cases were included after the duplicates (n = 158) and searches by title, abstract, and full text were eliminated. In 84 out of the 643 confirmed MPX cases (13.06% or n = 643), MPXV was discovered in seminal fluid. Reverse transcriptase polymerase chain reaction (RT-PCR) was used to identify MPXV, and samples taken from skin lesions (96.27%), pharynx or oropharynx (30.48%), and blood all had higher positivity rates than other samples (12.44%). Additionally, 99.85% of respondents were male with a mean age of 36, 98.45% engaged in MSM (men who have sex with men) sexual conduct, and human immunodeficiency virus (HIV) accounted for 56.9% of all STD cases. This study offers proof that MPXV can be found in the seminal fluid of MPX sufferers. Our data imply that MPXV transmission is a possibility in these samples and that MSM are more vulnerable to it. The creation of hygienic standards is essential for the early identification of MPX cases

    Air quality in North America's most populous city ? overview of the MCMA-2003 campaign

    No full text
    International audienceExploratory field measurements in the Mexico City Metropolitan Area (MCMA) in February 2002 set the stage for a major air quality field measurement campaign in the spring of 2003 (MCMA-2003). Involving over 100 scientists from more than 30 institutions in Mexico, the United States and Europe, MCMA-2003 revealed important new insights into the meteorology, primary pollutant emissions, ambient secondary pollutant precursor concentrations, photochemical oxidant production and secondary aerosol particle formation in North America's most populated and polluted megacity. A description of meteorological and atmospheric chemistry and aerosol microphysics measurements performed during MCMA-2003 is presented. More than 40 published or submitted MCMA-2003 research papers are reviewed and key discoveries pertinent to understanding and improving air quality in Mexico City and similar megacities in the developing world are summarized

    Infraestructura tecnolĂłgica de servicios semĂĄnticos para la Web SemĂĄntica

    Get PDF
    This project aims at creating a network of distributed interoperable semantic services for building more complex ones. These services will be available in semantic Web service libraries, so that they can be invoked by other systems (e.g., semantic portals, software agents, etc.). Thus, to accomplish this objective, the project proposes: a) To create specific technology for developing and composing Semantic Web Services. b) To migrate the WebODE ontology development workbench to this new distributed interoperable semantic service architecture. c) To develop new semantic services (ontology learning, ontology mappings, incremental ontology evaluation, and ontology evolution). d) To develop technological support that eases semantic portal interoperability, using Web services and Semantic Web Services. The project results will be open source, so as to improve their technological transfer. The quality of these results is ensured by a benchmarking process. Keywords: Ontologies and Semantic We

    Efecto De La Humedad Relativa Y La Temperatura En La Aplicacion De Insecticidas Organofosforados Y Carbamatos E Impacto En La Colinesterasa De Agro Productores De Tomate (Solanum Lycopersicum L.) En La Localidad De “San Luis, Chimborazo, Ecuador

    Get PDF
    This research aimed to determine the effect of relative humidity and temperature in the application of organophosphorus and carbamate insecticides and impact on the colinesterasa of tomato agro producers (Solanum lycopersicum L.) in the location of" San Luis, Chimborazo, Ecuador.The technique used was spectrophotometry. The cholinesterase test was performed on the one hundred and seventy patients of the five communities exposed between one year and more than ten years, in the handling and application of organophosphorus and carbamate insecticides. The method used was kinetic-spectrophotometric (405 nm at 37 ° C). Through the Kruskal Wallis test and the regression and correlation analysis it was determined the significance and the level of correlation and determination between the variables under study and their effect on cholinesterase levels. Concluding that the applications of the organophosphorus and carbamate insecticides under greenhouse with low relative humidity and high temperature, accompanied by the lack of precautions in the management of the crop, contribute to the decrease of the cholinesterase level of the agro producers

    Graves' disease is associated with a defective expression of the immune regulatory molecule galectin-9 in antigen-presenting dendritic cells

    Full text link
    Introduction Patients with autoimmune thyroid disease (AITD) show defects in their immune-regulatory mechanisms. Herein we assessed the expression and function of galectin-1 and galectin-9 (Gal-1, Gal-9) in dendritic cells (DCs) from patients with AITD. Materials and Methods Peripheral blood samples from 25 patients with Graves’ disease (GD), 11 Hashimoto’s thyroiditis (HT), and 24 healthy subjects were studied. Thyroid tissue samples from 44 patients with AITD and 22 patients with goiter were also analyzed. Expression and function of Gal-1 and Gal-9 was assessed by quantitative RT-PCR, immunofluorescence and flow cytometry. Results A diminished expression of Gal-9, but not of Gal-1, by peripheral blood DCs was observed in GD patients, mainly in those with GravesÂŽ ophthalmopathy, and a significant negative association between disease severity and Gal-9 expression was detected. In addition, the mRNA levels of Gal-9 and its ligand TIM-3 were increased in thyroid tissue from AITD patients and its expression was associated with the levels of Th1/Th12/Th17 cytokines. Immunofluorescence studies proved that intrathyroidal Gal-9 expression was confined to DCs and macrophages. Finally, in vitro functional assays showed that exogenous Gal-9 had a suppressive effect on the release of Th1/Th2/Th17 cytokines by DC/lymphocyte autologous co-cultures from both AITD patients and healthy controls. Conclusions The altered pattern of expression of Gal-9 in peripheral blood DCs from GD patients, its correlation with disease severity as well as its ability to suppress cytokine release suggest that Gal-9 could be involved in the pathogenesis of AITDThis work was supported by grants from the Fondo de Investigaciones Sanitarias (FISS) PI10/ 02521 and S2010/BMD-2328 TIRONET (Comunidad de Madrid), Spain (to MM) and the Fondo de CooperaciĂłn Internacional en Ciencia y TecnologĂ­a (FONCICYT) 95395, European Union-MĂ©xico (to RGA
    • 

    corecore