585 research outputs found

    Linfomas cutáneos de células T periféricas : estudio clínico, histológico inmunofenotípico e inmunogenotípico

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    Se presentan los resultados del estudio clínico, histológico inmunofenotípico e inmunofenotípico de 67 linfomas cutáneos de células t periféricas: 59 pacientes con MF/SS y 8 pacientes con otros linfomas T periféricos no MF/SS. Desde el punto de vista clínico-patológico se destacan las formas inusuales de presentación de MF, se aportan datos de inmunofenotípico útiles para el diagnóstico y el reordenamiento monoclonal en el SO de los estudios cutáneos

    Linfomas cutáneos de células T periféricas : estudio clínico, histológico inmunofenotípico e inmunogenotípico

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    Tesis Univ. Complutense de MadridSe presentan los resultados del estudio clínico, histológico inmunofenotípico e inmunofenotípico de 67 linfomas cutáneos de células t periféricas: 59 pacientes con MF/SS y 8 pacientes con otros linfomas T periféricos no MF/SS. Desde el punto de vista clínico-patológico se destacan las formas inusuales de presentación de MF, se aportan datos de inmunofenotípico útiles para el diagnóstico y el reordenamiento monoclonal en el SO de los estudios cutáneos.Depto. de MedicinaFac. de MedicinaTRUEpu

    Ocupaciones prehistóricas del barranco de Olula (Almansa, Albacete): Estudio de los registros líticos de superficie

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    La industria lítica proveniente de los registros de superficie localizados en el Barranco de Olula (Almansa), permite plantear en esta zona la existencia de ocupaciones al aire libre anteriores a la Edad de Bronce. Se presenta la documentación valorando de forma crítica los problemas del registro del que proceden. Por último, se contextualiza esta información en el marco del poblamiento de la Prehistoria Reciente del Corredor Almansa-Vinalopó y de otras áreas próximas

    An optimized full-configuration-interaction nuclear orbital approach to a “hard-core” interaction problem: Application to (3He)N–Cl2(B) clusters (N<4)

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    13 pages, 8 figures, 3 tables, 3 appendix.An efficient full-configuration-interaction nuclear orbital treatment has been recently developed as a benchmark quantum-chemistry-like method to calculate ground and excited “solvent” energies and wave functions in small doped AEest clusters (N<4) [M. P. de Lara-Castells, G. Delgado-Barrio, P. Villarreal, and A. O. Mitrushchenkov, J. Chem. Phys. 125, 221101 (2006)]. Additional methodological and computational details of the implementation, which uses an iterative Jacobi–Davidson diagonalization algorithm to properly address the inherent “hard-core” He–He interaction problem, are described here. The convergence of total energies, average pair He–He interaction energies, and relevant one- and two-body properties upon increasing the angular part of the one-particle basis set (expanded in spherical harmonics) has been analyzed, considering Cl2 as the dopant and a semiempirical model (T-shaped) He–Cl2(B) potential. Converged results are used to analyze global energetic and structural aspects as well as the configuration makeup of the wave functions, associated with the ground and low-lying “solvent” excited states. Our study reveals that besides the fermionic nature of 3He atoms, key roles in determining total binding energies and wave-function structures are played by the strong repulsive core of the He–He potential as well as its very weak attractive region, the most stable arrangement somehow departing from the one of N He atoms equally spaced on equatorial “ring” around the dopant. The present results for N=4 fermions indicates the structural “pairing” of two 3He atoms at opposite sides on a broad “belt” around the dopant, executing a sort of asymmetric umbrella motion. This pairing is a compromise between maximizing the 3He–3He and the He-dopant attractions, and suppressing at the same time the “hard-core” repulsion. Although the He–He attractive interaction is rather weak, its contribution to the total energy is found to scale as a power of three and it thus increasingly affects the pair density distributions as the cluster grows in size.This work has been partially supported by the CSICCAM, CICYT, and MICINN-CSIC Spanish Grants Nos. CCG08-CSIC/ESP-3680, FIS2007-62006, and 2007501004.Peer reviewe

    Exercising a firm’s growth options: A portfolio approach

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    Producción CientíficaThis paper investigates a firm’s decision to exercise its growth options within the current scope of business. We contend that the point at which a firm chooses whether or not to exercise such options depends on several strategic characteristics associated to its portfolio of businesses (i.e. level of diversification, average volatility of its current business, relatedness among them, and rivalry in its core business). Using a sample of U.S. companies from 1998 to 2013, we find evidence that a firm’s level of diversification and the volatility of its current business deter immediate growth option exercise. In contrast, relatedness and rivalry in its core business trigger growth options exercise. Our portfolio perspective differs from the bulk of the literature on real options, which evaluates each growth option exercise in isolation, and contributes to furthering knowledge on the drivers underlying a diversified firm's strategic investments.Junta de Castilla y León (grant VA260U14)Gobierno de la Comunidad de Madrid - Fondo Social Europeo (grant EARLYFIN, S2015/HUM-3353)Ministerio de Ciencia e Innovación (grants ECO2017-84864-P and ECO2017-85356-P

    Análisis DEA: eficiencia de los clubs de la Barclays Premier League

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    Este proyecto analiza la eficiencia de los veinte equipos de la Barclays Premier League inglesa durante la temporada 2012/2013 en términos económicos a través del análisis DEA (análisis envolvente de datos, conocido como DEA por sus siglas en inglés Data Envelopment Analysis), una de las técnicas más empleadas en la actualidad para este tipo de análisis. En primer lugar se realiza una introducción explicando de qué va a tratar el presente proyecto, aportando algunos datos económicos de un deporte tan popular como el fútbol, explicando las particularidades que conlleva un análisis económico cuando se trata de un tipo de empresas tan características y diferentes como son los equipos de fútbol, ya que necesitan conseguir buenos resultados deportivos además de tener unos datos económicos satisfactorios. En segundo lugar se explican las técnicas utilizadas para alcanzar la eficiencia. En este apartado se explica por qué se utiliza el análisis DEA y algunos conceptos importantes como el de benchmarking. Con todo ello se procede a realizar el análisis, explicando primero qué variables van a ser estudiadas (los veinte equipos de la primera división en la temporada a estudiar), y qué variables se van a utilizar tanto de entrada como de salida. En las de entrada se consideran los recursos de cada equipo, representados mediante la remuneración y los ingresos. En las de salida se consideran los resultados que cada equipo obtiene con dichos recursos, representados mediante el volumen de negocios (resultados económicos), los puntos obtenidos en la clasificación (resultados deportivos) y el número de seguidores en Facebook (resultados sociales o de seguimiento). El análisis DEA se realiza por medio del programa Matlab. Por último se analizan los resultados obtenidos, explicando las conclusiones más importantes, y dejando una puerta abierta a posibles análisis futuros con nuevas ideas

    Vibrational quenching of CO2(010) by collisions with O(3P) at thermal energies: A quantum-mechanical study

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    10 pages, 6 figures, 1 table, 1 appendix.-- PACS nrs.: 34.50.Ez; 33.20.Tp; 33.15.Mt; 31.15.Ar.The CO2(010)–O(3P) vibrational energy transfer (VET) efficiency is a key input to aeronomical models of the energy budget of the upper atmospheres of Earth, Venus, and Mars. This work addresses the physical mechanisms responsible for the high efficiency of the VET process at the thermal energies existing in the terrestrial upper atmosphere (150 K ≤ T ≤ 550 K). We present a quantum-mechanical study of the process within a reduced-dimensionality approach. In this model, all the particles remain along a plane and the O(3P) atom collides along the C(2v) symmetry axis of CO2, which can present bending oscillations around the linear arrangement, while the stretching C–O coordinates are kept fixed at their equilibrium values. Two kinds of scattering calculations are performed on high-quality ab initio potential energy surfaces (PESs). In the first approach, the calculations are carried out separately for each one of the three PESs correlating to O(3P). In the second approach, nonadiabatic effects induced by spin-orbit couplings (SOC) are also accounted for. The results presented here provide an explanation to some of the questions raised by the experiments and aeronomical observations. At thermal energies, nonadiabatic transitions induced by SOC play a key role in causing large VET efficiencies, the process being highly sensitive to the initial fine-structure level of oxygen. At higher energies, the two above-mentioned approaches tend to coincide towards an impulsive Landau-Teller mechanism of the vibrational to translational (V-T) energy transfer.This work has been partially supported by the European Project No. R113-2003-506079 and the DGICYT Spanish Grant Nos. FIS2004-02461 and CTQ-2004-02415/BQU. One of the authors (M.P.d.L.-C.) was supported by the "Ramón y Cajal" Programme and another author (M.L.-P.) by the Spanish projects Nos. REN2001-3249/CLI, ESP2004-01556, and by EC FEDER funds. The calculations presented here were performed at CINECA (the SuperComputer Center of the University of Bologna), the Instituto de Matemáticas y Física Fundamental (CSIC), and CESGA (the SuperComputer Center of Galicia).Peer reviewe

    Exact and quantum chemistry-like calculations in helium doped clusters: The He2Br2(X) example

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    7 pages, 2 figures, 2 tables.-- Issue title: "Proceedings from the Eleventh European Workshop on Quantum Systems in Chemistry and Physics", edited by Oleg Vasyutinskii, Jean Maruani, Piotr Piecuch, Gerardo Delgado-Barrio, Stephen Wilson.A quantum chemistry-like approach has been recently developed in our group to deal with HeN-BC doped helium clusters, where the BC dopant is a conventional diatomic molecule. The central idea is to consider the He atoms as electrons while the B and C atoms play the role of the nuclei in standard electronic structure calculations. The procedure provides energies and wavefunctions allowing to perform spectral simulations and, hence, making feasible to do proper comparisons with current experiments. However, because of the large difference of masses of He and electrons, and also to the replacement of Coulomb potentials by molecular interactions, it is worthy to assess to what extent the approximations involved in this model (decoupling of orbital angular momenta of the He atoms from the BC rotation and adiabatic separation of the BC stretch versus the He motions) lead to accurate results. In this work we address these issues on the 4He2-Br2(X) system, containing a couple of bosonic He atoms for which variational calculations can be performed.Funded by DGICYT Spanish grants (FIS2004-02461, CTQ2004-02415/BQU) and Spanish "Ramón y Cajal" Programme, Ministerio de Educación y Ciencia; Grant Number: PDRyC-2003-001015, PDRyC-2006-001017.Peer reviewe

    Global evaluation of the chemical hazard of recycled tire crumb rubber employed on worldwide synthetic turf football pitches

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    Social and environmental concern about the use of crumb rubber from end-of-life car tires in the construction of different sport and recreational facilities is increasing due to the presence of hazardous compounds. The aim of this research was the assessment of 42 organic chemicals, including polycyclic aromatic hydrocarbons (PAHs), phthalates, adipates, antioxidants and vulcanisation agents in a large number of infill samples (91) from synthetic turf football pitches of diverse characteristics and geographical origin. Samples were taken worldwide, in 17 countries on 4 continents, to show the global dimension of this problem. Ultrasound assisted extraction was employed to extract the target compounds, followed by gas chromatography coupled to tandem-mass spectrometry (UAE-GC–MS/MS). Seventy-eight crumb rubber samples as well as thirteen samples of alternatives materials, such as cork granulates, thermoplastic elastomers and coconut fibre, were analyzed. The results highlight the presence of all target PAH in most rubber samples at concentrations up to μg g−1, including the eight ECHA (European Chemicals Agency) PAHs considered as carcinogenic, and anthracene (ANC), pyrene (PYR) and benzo[ghi]perylene (B[ghi]P), catalogued as substances of very high concern (SVHC). Endocrine disruptors such as some plasticizers (mainly phthalates), and other compounds like benzothiazole (BTZ) and 2-mercaptobenzothiazole (MBTZ) were found reaching the mg g−1 level. This confirms the presence of the hazardous substances in the recycled crumb rubber samples collected all around the world. Three crumb rubber samples exceeded the limit of 20 μg g−1 for the sum of the eight ECHA PAHs. Regarding the chemical composition of other infill alternatives, cork appears to be adequate, while the thermoplastic elastomers contained high levels of some plasticizers. In addition, the plastic infill as well as the crumb rubber both are microplastics. Microplastics are considered contaminants of emerging concern since they do not biodegrade and remain in the environment for a long timeThis research was supported by projects RETOS PID2019-104336RB-I00 (Ministry of Science and Innovation, Spain) and UNST10-1E-491 (Infrastructure Program, Ministry of Science and Innovation, Spain). The authors belong to RED2018-102522-T (Ministry of Science, Innovation and Universities, Spain) and to the Galician Competitive Research Groups IN607B 2019/13 and ED431 2020/06 (Xunta de Galicia). This study is based upon work from COST Action CA16215 and from the Sample Preparation Study Group and Network, supported by the Division of Analytical Chemistry of the European Chemical Society. All these programs are co-funded by FEDER (EU). This work was also financially supported by: (i) Base Funding UIDB/00511 2020 of the Laboratory for Process Engineering, Environment, Biotechnology and Energy (LEPABE), by national funds through the FCT/ MCTES (PIDDAC); (ii) Project SAFEGOAL (Ref. PTDC/EQU-EQU/28101/2017; POCI-01-0145-FEDER-028101), funded by FEDER funds through COMPETE2020 – Programa Operacional Competitividade e Internacionalização (POCI) and by national funds (PIDDAC) through FCT/ MCTES. N.R. thanks the Portuguese Foundation for Science and Technology (FCT) for the financial support of his work contract through the Scientific Employment Stimulus - Institutional Call - [CEECINST/00049/2018]S

    GeoBotánica: Aplicación Web para la visualización, análisis y estudio de taxones vegetales. Caso de estudio Cuenca Media del Tajo.

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    La geobotánica (fitogeografía), rama de la biogeografía, estudia cómo la tectónica de placas y las orogénesis determinan una distribución de tierras, mares y accidentes geográficos, el aislamiento o la conexión de poblaciones, la distribución espacial de las especies y los fenómenos de especialización. La corología, por su parte, se ocupa de la distribución geográfica de cada especie, siendo el clima y el suelo los principales factores que influyen en la misma. Como resumen podemos decir que para la geobotánica es de interés poder obtener y analizar: mapas corológicos, los factores limitantes climáticos y químicos, y la relación con el medio y otras especies. El objetivo de la aplicación Web desarrollada, basada en estándares OGC para el acceso y visualización de información geográfica, es dotar a los geobotánicos de una herramienta sencilla y accesible en Web, que ayude en los procesos de estudio y análisis de la distribución de especies vegetales en el territorio y sus condicionantes. La aplicación, desarrollada a partir de los datos del inventario botánico del profesor Martínez Labarga de la cuenca media del Tajo, permite realizar estudios y análisis geobotánicos, apoyándose en la confección de mapas corológicos y la correlación de la distribución de cada especie con las magnitudes climáticas de temperatura o precipitación y las características de los suelos sobre los que aparece. Esta aplicación dispone de una arquitectura de 3 capas (almacenes de datos, servicios y clientes) y ha sido desarrollada con tecnologías OpenSource (PostGIS, Geoserver, Apache httpd, OpenLayers, GeoExt, php) y consume datos propios publicados mediante estándares OGC (WMS y WFS) y capas de la IDE tanto de suelos (litológico, geológico, topográfico, ortoimágenes) como climáticos (precipitaciones y temperaturas ?CREAF). El desarrollo de la aplicación y la prueba de concepto han permitido identificar algunos problemas de rendimiento a la hora de realizar consultas al Atlas Climático de la Península Ibérica y se ha propuesto una solución basada en el cacheado de datos consultados en tiempo de ejecució
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