2,133 research outputs found

    A clear signature of the breakup modes for 9Be on a proton target at 5.6 MeV/nucleon

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    The breakup of 9Be is studied via an inelastic scattering experiment on a proton target at 5.6 A MeV in inverse kinematics. Two of the three cluster constituents (α and α) as well as the proton target recoil were recorded in a triple coincidence mode allowing a full kinematics approach analysis. In this respect relative α - α and α - n, Q-value and 9Be excitation spectra, energy spectra for all fragments as well as the energy spectrum of the recoil proton were reconstructed. A clear signature of the two breakup sequential modes (5He + 4He and 8Be + n) was identified via the recoiling proton reconstructed spectra together with the direct breakup decay. A strong 5He + 4He mode was observed compatible with previous beta decay experiments

    Economía y medio ambiente en la Unión Europea: la apuesta por la sostenibilidad

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    El presente trabajo refierese a los Tratados Internacionales de la Unión Europea sobre la Politica Ambiental Comun. Los primeros documentos internacionales, embrión de la CE no previan cualquer politica ambiental comun. Fue con el aumento de los niveles de contaminación y la constatación de que los daños nos se quedavan a un solo Estado y que las legislaciones nacionales no atendian las necesidades, que empesaran los mecanismos comunes de preservación ambiental, apostando la CE por un Desarrollo sostenible

    La protección de los datos genéricos

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    T-cell allorecognition of donor glutathione S-transferase T1 in plasma cell-rich rejection

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    AIM: To investigate the role of glutathione S-transferase T1 donor-specific T lymphocytes in plasma cell-rich rejection of liver allografts. METHODS: The study group included 22 liver transplant patients. Among them, 18 patients were mismatched for the glutathione S-transferase T1 (GSTT1) alleles (don+/rec-), and 4 were matched (don+/rec+). Seven of the mismatched patients produced anti-GSTT1 antibodies and developed plasma cell-rich rejection (former de novo immune hepatitis). For the detection of specific T lymphocytes, peripheral blood mononuclear cells were collected and stored in liquid nitrogen. The memory T cell response was studied by adding to the cell cultures to a mix of 39 custom-made, 15-mer overlapping peptides, which covered the entire GSTT1 amino acid sequence. The specific cellular response to peptides was analyzed by flow cytometry using the markers CD8, CD4, IL-4 and IFNγ. RESULTS: Activation of CD8+ T cells with different peptides was observed exclusively in the group of patients with plasma-cell rich rejection (3 out of 7), with production of IL-4 and/or IFNγ at a rate of 1%-4.92% depending on the peptides. The CD4+ response was most common and not exclusive for patients with the disease, where 5 out of 7 showed percentages of activated cells from 1.24% to 31.34%. Additionally, two patients without the disease but with the mismatch had cells that became stimulated with some peptides (1.45%-5.18%). Highly unexpected was the finding of a double positive CD4+CD8low T cell population that showed the highest degree of activation with some of the peptides in 7 patients with the mismatch, in 4 patients with plasma cell-rich rejection and in 3 patients without the disease. Unfortunately, CD4+CD8low cells represent 1% of the total number of lymphocytes, and stimulation could not be analyzed in 9 patients due to the low number of gated cells. Cells from the 4 patients included as controls did not show activation with any of the peptides. CONCLUSION: Patients with GSTT1 mismatch can develop a specific T-cell response, but the potential role of this response in the pathogenesis of plasma cell-rich rejection is unknown

    Hybrid Architecture to Support Context‐Aware Systems

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    Any system that is said to be context‐aware is capable of monitoring continuously the surrounding environment, that is, capable of prompt reaction to events and changing conditions of the environment. The main objective of a context‐aware system is to be continuously recognizing the state of the environment and the users present, in order to adjust the environment to an ideal state and to provide personalized information and services to users considering the user profile. In this chapter, we describe an architecture that relies on the incorporation of intelligent multi‐agent systems (MAS), sensor networks, mobile sensors, actuators, Web services and ontologies. We describe the interaction of these technologies into the architecture aiming at facilitating the construction of context‐aware systems

    Bubble and Dew Point Calculations in Multicomponent and Multireactive Mixtures

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    Bubble and dew point calculations are useful in chemical engineering and play an important role in the study of separation equipments for non-reactive and reactive mixtures. To the best of the authors’s knowledge, few methods have been proposed for these calculations in systems with several chemical reactions. The objective of this paper is to introduce new conditions for performing bubble and dew point calculations in reactive mixtures. We have developed these conditions based on the application of transformed variables of Ung and Doherty (1995). Using these transformed variables, the solution space is restricted to compositions that are already at chemical equilibrium and by consequence the problem dimension is also reduced. The reliability and efficiency of three equation-solving methods are tested and compared using our equilibrium conditions: a) a simultaneous equation-solving approach using Newton method (SESN), b) an equation-decoupling approach using successive substitution method (EDSS) and c) an optimization approach using the stochastic optimization method Simulated Annealing(OSA). Our results indicated that even for simple reactive systems, bubble and dew point calculations are challenging for classical equation-solving methods and require robust strategies. We conclude that OSA and EDSS methods are reliable to locate bubble and dew points in reactive systems. EDSS is more efficient than OSA; however, OSA does not need initial guesses and is more suitable for difficult problems

    Hermeneutics and pedagogy : educational practice in the speech about education

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    En el presente trabajo reflexionamos sobre la relación que existe entre la práctica educativa y el discurso teórico sobre la práctica. Partiendo de un planteamiento hermenéutico, analizamos la relación que en pedagogía existe entre los temas de la certidumbre, la validación y la evidencia en los métodos cualitativos. En este sentido, la propuesta de un «círculo hermenéutico de interpretaciones», para la comprensión de un texto o una práctica educativa que es susceptible de ser leída como un texto, es un predicamento que no resuelve del todo la tarea mencionada. Proponemos un nivel de validación que permita romper el círculo de libres interpretaciones, llegando a alcanzarlo a través del análisis y la reflexión de tres caminos: la fuerza del argumento, el consenso de los científicos y la práctica educativa. Se concluye con la idea de que la práctica educativa misma es la mejor fuente de validación de la teoríaIn this paper we reflect on the relationship between educational practice and the theoretical discourse on the practice. From a hermeneutic approach, we analyzed the relationship, within the pedagogical field, between the issues of certitude, validation and evidence to qualitative inquiry. In this regard, the proposal of a «hermeneutical circle of interpretations» built up by numerous interpreters when a text or a fact-resembled text is under scrutiny does not resolve the above mentioned task. We propose a reasonable level of validation in order to break down the circle of free interpretations, being achieved through analysis and reflection of three channels: the strength of interpretative argument, the scholar community consensus and the educational practice itself. It concludes with the idea that educational practice itself is the best way to validate the theor

    Hermeneutics and pedagogy : educational practice in the speech about education

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    En el presente trabajo reflexionamos sobre la relación que existe entre la práctica educativa y el discurso teórico sobre la práctica. Partiendo de un planteamiento hermenéutico, analizamos la relación que en pedagogía existe entre los temas de la certidumbre, la validación y la evidencia en los métodos cualitativos. En este sentido, la propuesta de un «círculo hermenéutico de interpretaciones», para la comprensión de un texto o una práctica educativa que es susceptible de ser leída como un texto, es un predicamento que no resuelve del todo la tarea mencionada. Proponemos un nivel de validación que permita romper el círculo de libres interpretaciones, llegando a alcanzarlo a través del análisis y la reflexión de tres caminos: la fuerza del argumento, el consenso de los científicos y la práctica educativa. Se concluye con la idea de que la práctica educativa misma es la mejor fuente de validación de la teoríaIn this paper we reflect on the relationship between educational practice and the theoretical discourse on the practice. From a hermeneutic approach, we analyzed the relationship, within the pedagogical field, between the issues of certitude, validation and evidence to qualitative inquiry. In this regard, the proposal of a «hermeneutical circle of interpretations» built up by numerous interpreters when a text or a fact-resembled text is under scrutiny does not resolve the above mentioned task. We propose a reasonable level of validation in order to break down the circle of free interpretations, being achieved through analysis and reflection of three channels: the strength of interpretative argument, the scholar community consensus and the educational practice itself. It concludes with the idea that educational practice itself is the best way to validate the theor

    Revisión histórica del fenómeno educativo indígena en el nororiente delCauca (Colombia)

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    El trabajo que presentamos pretende, desde un punto de vista comparado, y en perspectiva histórica, presentar la realidad del fenómeno educativo colombiano, en concreto las políticas y prácticas educativas en zonas indígenas. La realidad colombiana se presta a muchas intervenciones y reflexiones filosóficas, educativas y políticas acerca de los indígenas y su papel, representatividad y visibilidad en la sociedad. La educación indígena sigue un proceso de marcha, en ocasiones parece lento, en otras rápido; en este momento siguen existiendo problemas prioritarios como la tierra, la producción, la salud, etc. No obstante para las hoy comunidades indígenas, el planteamiento educativo es muy importante y lo enmarcan en su problemática actual que hoy viven como comunidades indígenas.The present paper seeks,from a comparative perspective, and historical perspective, presenting the phenomenon Colombian education,specifically educational policies and practices in indigenous areas. The situation in Colombia, lends itself to many interventions and philosophical, educational and policy on indigenous people and its role,representation and visibility in society.Indigenous education is an ongoing process,sometimes seems slow, others fast, at this time remain priority issues such as land,production, health, etc. But for today, indigenous communities, the educational approach is very important and fall within its current problems today live as indigenous communities
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