3,999 research outputs found

    Detectors and Concepts for sub-100 ps timing with gaseous detectors

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    We give a short compendium of the main ongoing detectors and concepts capable of performing accurate sub-100 ps timing at high particle fluxes and on large areas, through technologies based on gaseous media. We briefly discuss the state-of-the-art, technological limitations and prospects, and a new bizarre idea

    Infraestructura de datos espaciales en medio ambiente y acceso a la información ambiental en Andalucía. El canal de la red de información ambiental de Andalucía.

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    La Consejería de Medio Ambiente de la Junta de Andalucía ha puesto en marcha un sistema para poder cumplir adecuadamente los requisitos derivados de la normativa vigente en dos vertientes que están muy relacionadas: la del acceso a la información ambiental y la de las Infraestructuras de Datos Espaciales. Ambas vertientes, que vienen definidas por sendas Directivas, han condicionado la solución establecida que pasa por la creación mediante el desarrollo normativo adecuado de un instrumento, la Red de Información Ambiental de Andalucía (REDIAM). Esta red se ha dotado de una plataforma en entorno web, el Canal de la Red de Información Ambiental de Andalucía, en la que confluyen elementos constitutivos de una Infraestructura de Datos Espaciales (IDE) con otros de obtención y acceso al dato como es el de de solicitud de información ambiental o la descarga directa, y con elementos de navegación que pretenden facilitar al público en general el acceso a este conjunto de servicios y productos. Puesto en explotación el 29 de enero de 2009, hoy podemos hacer balance del uso que ha registrado en su primer año.The Ministry of Environment of the Junta de Andalucía has launched a system to carry out the requirements under current regulations in two areas which are closely related: access to environmental information and Spatial Data Infrastructures. Both sides, which are defined by EU Directives, have conditioned the solution through the developing an appropriate regulatory instrument, the Environmental Information Network of Andalusia (REDIAM). This network has set up a web-based platform, the Andalusian Environmental Information Network Channel, which combines elements of a Spatial Data Infrastructure (SDI) with other elements of data collection and access like the environmental information request or direct download, and navigation elements that are intended to facilitate the general public access to the package of services and products. Having been put into operation on January 29, 2009, today we can assess the use it has registered in its first year

    Handbook of Alkali-Activated Cements, Mortars and Concretes

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    This book provides an updated state-of-the-art review on new developments in alkali-activation. The main binder of concrete, Portland cement, represents almost 80% of the total CO2 emissions of concrete which are about 6 to 7% of the Planet's total CO2 emissions. This is particularly serious in the current context of climate change and it could get even worse because the demand for Portland cement is expected to increase by almost 200% by 2050 from 2010 levels, reaching 6000 million tons/year. Alkali-activated binders represent an alternative to Portland cement having higher durability and a lower CO2 footprint. Reviews the chemistry, mix design, manufacture and properties of alkali-activated cement-based concrete binders. Considers performance in adverse environmental conditions. Offers equal emphasis on the science behind the technology and its use in civil engineering

    Marginally Trapped Surfaces in the Nonsymmetric Gravitational Theory

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    We consider a simple, physical approach to the problem of marginally trapped surfaces in the Nonsymmetric Gravitational Theory (NGT). We apply this approach to a particular spherically symmetric, Wyman sector gravitational field, consisting of a pulse in the antisymmetric field variable. We demonstrate that marginally trapped surfaces do exist for this choice of initial data.Comment: REVTeX 3.0 with epsf macros and AMS symbols, 3 pages, 1 figur

    Acoso psicológico, organización e identidad : análisis desde un foro virtual

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    Las interacciones que tienen lugar en los foros de discusión de Internet se vienen empleando como fuente de información para el análisis de distintas temáticas sociales. Estos foros constituyen en muchos casos un nexo de (re)unión para las comunidades de afectados por problemas de distinta índole, convirtiéndose así el ciberespacio en un marco referencial para el estudio de los mismos. Por otro lado, la disponibilidad de los discursos íntegros de los participantes en estos foros y el carácter textual de los contenidos incluidos facilitan el empleo de metodologías de tipo cualitativo para el análisis de los fenómenos. En el presente trabajo analizamos el acoso psicológico en el marco de los foros de Internet con el objeto de profundizar en sus implicaciones subjetivas, especialmente los aspectos relacionados con la formulación de las identidades; y en sus implicaciones organizacionales, centrando la atención en las dimensiones estructurales y funcionales.Interactions in internet discussion forums provide data on a variety of social issues. Forums are often a meetingplace for people affected by a given problem; in fact, cyberspace has become a framework of reference in the study of such interaction. The ready availability of the participants' discourse, and the textual nature of the forum's contents, facilitate the use of qualitative methodologies. The present article analyses harassment in internet forums in order to study its subjective implications, specially those aspects related to the formulation of participants' identities. The article also explores the organizational implications of harassment, focusing on its structural and functional dimensions

    Factor V Leiden and prothrombin G20210A among Chilean patients with venous and arterial thrombosis

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    Iván Palomo. Departamento de Bioquímica Clínica e Inmunohematología, Facultad de Ciencias de la Salud. Universidad de Talca, Talca, Chile. Casilla 747,Talca, Chile.Factor V Leiden and G20210A mutation of prothrombin gene are two important genetic polymorphisms associated with an increased risk for thrombosis. Aim: To establish the prevalence of factor V Leiden and prothrombin G20210A mutation in the Chilean population and their association to venous and arterial thromboembolism. Material and methods: A case-control study was conducted where 149 patients with thrombosis (87 with arterial and 62 with venous thrombosis) confirmed by CAT-scan, electrocardiogram and cardiac enzymes or Doppler depending on the case, and 160 healthy blood donors were genetically analyzed for the presence of both polymorphisms. Results: Factor V Leiden mutation was found in 5.4% of patients and in 1.3% of healthy controls (p=0.04). Heterozygosity for G20210A prothrombin mutation was found in 5.4% of patients and in 2.5% of the control group (p=NS). When arterial and venous thrombosis were considered as separate entities, 4.6% of patients with arterial thrombosis and 6.5% with venous thrombosis presented factor V Leiden (p=NS). Likewise, 8.1% of patients with venous thrombosis and 3.5% of patients with arterial thrombosis had G20210A prothrombin mutation (p=NS). Conclusions: In non selected consecutive Chilean patients with arterial and venous thrombosis the frequency of factor V Leiden and prothrombin G20210A is less than we could expect from their prevalence in the general populatio

    Expresión de ICAM-1 en el Endotelio de Arterias Humanas Mediante Inmunohistoquímica

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    Moore-Carrasco, R (reprint author), Univ Talca, Fac Ciencias Salud, Dept Bioquim Clin & Inmunohematol, Programa Invest Factores Riesgo Enfermedades Card, POB 747, Talca, Chile.Cardiovascular diseases (CVD) are the leading cause of death in the world. Among them the ischemic type are of great importance. where the development of atherosclerotic plaques is the central pathophysiological process. The study of atherosclerosis is critical to understand how this disease process begins and factors influencing its development. Various laboratory methods, including immunohistochemistry, allow the recognition of cells and molecules involved in the atheromatous process that are interacting according to the progression of the lesion. A marker of endothelial dysfunction is the increased expression of intercellular adhesion molecule ICAM-1. In this paper, an immunohistochemistry method was standardized for the adhesion molecule ICAM-1, and its expression was studied in healthy human arteries with atheromatous plaque. In samples of human arteries with atherosclerotic disease, the expression of ICAM-1 was observed lobe increased, but was hardly recognizable. This mainly because the tissue used as a control for standardization was a tonsil with an inflammatory process and hyperplasia, which significantly increases the expression of ICAM-1. The implementation of the immunohistochemistry method for ICAM-1 in human arteries will reveal endothelial dysfunction states that will enable a future design and implementation of methods of diagnosis in atherosclerotic processes in the early stages

    Computer model validation with functional output

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    A key question in evaluation of computer models is Does the computer model adequately represent reality? A six-step process for computer model validation is set out in Bayarri et al. [Technometrics 49 (2007) 138--154] (and briefly summarized below), based on comparison of computer model runs with field data of the process being modeled. The methodology is particularly suited to treating the major issues associated with the validation process: quantifying multiple sources of error and uncertainty in computer models; combining multiple sources of information; and being able to adapt to different, but related scenarios. Two complications that frequently arise in practice are the need to deal with highly irregular functional data and the need to acknowledge and incorporate uncertainty in the inputs. We develop methodology to deal with both complications. A key part of the approach utilizes a wavelet representation of the functional data, applies a hierarchical version of the scalar validation methodology to the wavelet coefficients, and transforms back, to ultimately compare computer model output with field output. The generality of the methodology is only limited by the capability of a combination of computational tools and the appropriateness of decompositions of the sort (wavelets) employed here. The methods and analyses we present are illustrated with a test bed dynamic stress analysis for a particular engineering system.Comment: Published in at http://dx.doi.org/10.1214/009053607000000163 the Annals of Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical Statistics (http://www.imstat.org

    Clinical guideline SEOM: cancer of unknown primary site

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    Cancer of unknown primary site is a histologically confirmed cancer which is manifested in advanced stage, with no identifiable primary site after the use of standard diagnostic procedures. Patients are initially placed into one of categories based upon the examination of the initial biopsy: adenocarcinoma, squamous cell carcinoma, neuroendocrine carcinoma and poorly differentiated carcinoma. Appropriate patient management requires an understanding of several clinicopathologic features that help to identify several subsets of patients with more responsive tumors

    El futuro de las revistas científicas españolas: un esfuerzo científico, social e institucional

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    In spite of the increasingly high level of scientific production by Spanish researchers on terrestrial vertebrate biology, Spanish journals on this topic are, paradoxically, in a delicate situation that seriously threatens their future. This paper surnrnarises the results obtained in an analysis of the current situation of these journals and their perspectives for the near future: Such results are fully applicable to most scientific journals edited both in Spain and in countries in a similar situation. The international status of a journal determines the quality and quantity of original works that receives and publishes. The quality of the published papers was, in turn, the rnain deterrnining factor of this international status until the appearance of the "impact factors" elaborated by a private company, the North American lnstitute for Scientific lnformation (ISI), The ISI also elaborates a list of journals classified according to their irnpact factors, as well as to a nurnber of inclusion criteria. In spite of the fact that both the irnpact factors and the criteria for inclusion of journals are now under close scrutiny by the scientific cornrnunity, journals not included on this list are considered "non-prestigious". The future of such journals is thus threatened as this " label" prevents scientists frorn subrnitting their good quality papers to thern. Few Spanish scientific journals are included on the list, and the ISI is reluctant to lengthen it unless the journals are new, published in English and, usually, supported by the major publishing houses which monopolise the international rnarket of scientific publications. Most Spanish scientific journals, especially those focused on terrestrial vertebrates, are published by scientific societies integrated by both professional scientists and naturalists interested in the study of these organisrns. The Spanish Administration partially supported some of them in the past through specific funding. In addition, sorne journals were fully supported by public funds, but they have either disappeared or are not published periodically. This situation contradicts the governrnent's objectives to prornote the Spanish language and to obtain returns on the investment in training high-level scientists. On this basis, one way to ensure the long-term rnaintenance of Spanish journals would be to enhance alternatives such as the publication of local studies or the support and training of novel scientists. This option may be carried out by scientific societies thernselves without institutional aid by means of ¡.e. reducing the subscription cost, as far as some disagreernents between the scientific and non-scientific partners were solved properly. However, this would limit the international projection of the Spanish journals. The only alternative would be a social, institutional and political agreement aimed at promoting those Spanish journals, either already established or new, with the best perspectives for international diffusion. The final goal should be the inclusion of these journals on the ISI list. The co-ordinated efforts of scientists, scientific societies and the administration would thus eventually reach the objective of maintaining high-quality scientific journals, one of the main mid-term returns on the investment in science. Key words: Problems for long-term maintenance, Scientific journals, Scientific policy, Scientific societies, Social and institutional support, Terrestrial vertebrates.In spite of the increasingly high level of scientific production by Spanish researchers on terrestrial vertebrate biology, Spanish journals on this topic are, paradoxically, in a delicate situation that seriously threatens their future. This paper surnrnarises the results obtained in an analysis of the current situation of these journals and their perspectives for the near future: Such results are fully applicable to most scientific journals edited both in Spain and in countries in a similar situation. The international status of a journal determines the quality and quantity of original works that receives and publishes. The quality of the published papers was, in turn, the rnain deterrnining factor of this international status until the appearance of the "impact factors" elaborated by a private company, the North American lnstitute for Scientific lnformation (ISI), The ISI also elaborates a list of journals classified according to their irnpact factors, as well as to a nurnber of inclusion criteria. In spite of the fact that both the irnpact factors and the criteria for inclusion of journals are now under close scrutiny by the scientific cornrnunity, journals not included on this list are considered "non-prestigious". The future of such journals is thus threatened as this " label" prevents scientists frorn subrnitting their good quality papers to thern. Few Spanish scientific journals are included on the list, and the ISI is reluctant to lengthen it unless the journals are new, published in English and, usually, supported by the major publishing houses which monopolise the international rnarket of scientific publications. Most Spanish scientific journals, especially those focused on terrestrial vertebrates, are published by scientific societies integrated by both professional scientists and naturalists interested in the study of these organisrns. The Spanish Administration partially supported some of them in the past through specific funding. In addition, sorne journals were fully supported by public funds, but they have either disappeared or are not published periodically. This situation contradicts the governrnent's objectives to prornote the Spanish language and to obtain returns on the investment in training high-level scientists. On this basis, one way to ensure the long-term rnaintenance of Spanish journals would be to enhance alternatives such as the publication of local studies or the support and training of novel scientists. This option may be carried out by scientific societies thernselves without institutional aid by means of ¡.e. reducing the subscription cost, as far as some disagreernents between the scientific and non-scientific partners were solved properly. However, this would limit the international projection of the Spanish journals. The only alternative would be a social, institutional and political agreement aimed at promoting those Spanish journals, either already established or new, with the best perspectives for international diffusion. The final goal should be the inclusion of these journals on the ISI list. The co-ordinated efforts of scientists, scientific societies and the administration would thus eventually reach the objective of maintaining high-quality scientific journals, one of the main mid-term returns on the investment in science. Key words: Problems for long-term maintenance, Scientific journals, Scientific policy, Scientific societies, Social and institutional support, Terrestrial vertebrates.In spite of the increasingly high level of scientific production by Spanish researchers on terrestrial vertebrate biology, Spanish journals on this topic are, paradoxically, in a delicate situation that seriously threatens their future. This paper surnrnarises the results obtained in an analysis of the current situation of these journals and their perspectives for the near future: Such results are fully applicable to most scientific journals edited both in Spain and in countries in a similar situation. The international status of a journal determines the quality and quantity of original works that receives and publishes. The quality of the published papers was, in turn, the rnain deterrnining factor of this international status until the appearance of the "impact factors" elaborated by a private company, the North American lnstitute for Scientific lnformation (ISI), The ISI also elaborates a list of journals classified according to their irnpact factors, as well as to a nurnber of inclusion criteria. In spite of the fact that both the irnpact factors and the criteria for inclusion of journals are now under close scrutiny by the scientific cornrnunity, journals not included on this list are considered "non-prestigious". The future of such journals is thus threatened as this " label" prevents scientists frorn subrnitting their good quality papers to thern. Few Spanish scientific journals are included on the list, and the ISI is reluctant to lengthen it unless the journals are new, published in English and, usually, supported by the major publishing houses which monopolise the international rnarket of scientific publications. Most Spanish scientific journals, especially those focused on terrestrial vertebrates, are published by scientific societies integrated by both professional scientists and naturalists interested in the study of these organisrns. The Spanish Administration partially supported some of them in the past through specific funding. In addition, sorne journals were fully supported by public funds, but they have either disappeared or are not published periodically. This situation contradicts the governrnent's objectives to prornote the Spanish language and to obtain returns on the investment in training high-level scientists. On this basis, one way to ensure the long-term rnaintenance of Spanish journals would be to enhance alternatives such as the publication of local studies or the support and training of novel scientists. This option may be carried out by scientific societies thernselves without institutional aid by means of ¡.e. reducing the subscription cost, as far as some disagreernents between the scientific and non-scientific partners were solved properly. However, this would limit the international projection of the Spanish journals. The only alternative would be a social, institutional and political agreement aimed at promoting those Spanish journals, either already established or new, with the best perspectives for international diffusion. The final goal should be the inclusion of these journals on the ISI list. The co-ordinated efforts of scientists, scientific societies and the administration would thus eventually reach the objective of maintaining high-quality scientific journals, one of the main mid-term returns on the investment in science. Key words: Problems for long-term maintenance, Scientific journals, Scientific policy, Scientific societies, Social and institutional support, Terrestrial vertebrates
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