722 research outputs found

    GuaB Activity Is Required in Rhizobium tropici During the Early Stages of Nodulation of Determinate Nodules but Is Dispensable for the Sinorhizobium meliloti–Alfalfa Symbiotic Interaction

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    The guaB mutant strain Rhizobium tropici CIAT8999-10T is defective in symbiosis with common bean, forming nodules that lack rhizobial content. In order to investigate the timing of the guaB requirement during the nodule formation on the host common bean by the strain CIAT899-10.T, we constructed gene fusions in which the guaB gene is expressed under the control of the symbiotic promoters nodA, bacA, and nifH. Our data indicated that the guaB is required from the early stages of nodulation because full recovery of the wild-type phenotype was accomplished by the nodA-guaB fusion. In addition, we have constructed a guaB mutant derived from Sinorhizobium meliloti 1021, and shown that, unlike R. tropici, the guaB S. meliloti mutant is auxotrophic for guanine and induces wild-type nodules on alfalfa and Medicago truncatula. The guaB R. tropici mutant also is defective in its symbiosis with Macroptilium atropurpureum and Vigna unguiculata but normal with Leucaena leucocephala. These results show that the requirement of the rhizobial guaB for symbiosis is found to be associated with host plants that form determinate type of nodules.Fil: Collavino, Mónica Mariana. Universidad Nacional de La Plata. Facultad de Ciencias Exactas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; ArgentinaFil: Riccillo, Pablo M.. Universidad Nacional de La Plata. Facultad de Ciencias Exactas; ArgentinaFil: Grasso, Daniel Horacio. Universidad Nacional de La Plata. Facultad de Ciencias Exactas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Crespi, Martín. Centre National de la Recherche Scientifique; FranciaFil: Aguilar, Orlando Mario. Universidad Nacional de La Plata. Facultad de Ciencias Exactas; Argentin

    Quantum optical signals in telecommunication networks

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    Introducción a una red óptica metropolitana cuántica donde señales cuánticas y convencionales son multiplexadas en longitud de onda utilizando bandas separadas del espectro óptico. El enrutado se realiza con componentes pasivos para no perturbar los qubits. Se estudian dos redes: red de acceso WDM-PON y red metropolitana completa con backbone DWDM y redes de acceso WDM-PON

    Actual treatment of attention deficit hyperactivity disorder (ADHD)

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    El tratamiento del trastorno por défi cit de atención e hiperactividad (TDAH) incluye intervenciones farmacológicas, psicosociales y educativas, y en él se aconseja un diseño personalizado teniendo en cuenta las características del paciente, el tipo de trastorno y la comorbilidad que lo acompaña. Los fármacos de primera línea son el psicoestimulante metilfenidato (MTF) y atomoxetina (ATX), un simpaticomimético de acción central no estimulante. Ambos reducen las manifestaciones clínicas de inquietud, inatención e impulsividad, mejorando la calidad de las relaciones sociales y el rendimiento académico. Metilfenidato bloquea el transportador presináptico de dopamina (DA) y noradrenalina (NA), aumentando la concentración de estos neurotransmisores en el espacio presináptico neuronal. Se presenta en formas de liberación inmediata (LI) (Rubifen® y Medicebran® en preparados de acción prolongada con tecnología OROS® [osmotic controlled-release oral delivery system], Concerta® y Metilfenidato Sandoz®) y en pellets (Medikinet®), que permiten seleccionar adecuadamente la dosis y la pauta posológica. Las formas de LI pueden inducir efecto rebote al provocar un pico plasmático elevado que decae en poco tiempo. Atomoxetina (Strattera®) es un inhibidor muy selectivo y potente del transportador presináptico de NA; aumenta los niveles de NA y DA en la corteza prefrontal, pero no en las regiones corticales relacionadas con el desarrollo de tics o riesgo de abusos de sustancias. Puede ser la alternativa a MTF cuando éste pierde efi cacia o está contraindicado. La efectividad de ambos fármacos debe considerarse a partir de las 2-4 semanas. Sus reacciones adversas son numerosas y con frecuencia causan malestar, lo que difi culta la adherencia. Por ello es necesario el seguimiento de estos pacientes, y el farmacéutico puede ejercer un papel destacado para mejorar el cumplimiento y los efectos de la farmacoterapiaTreatment of attention defi cit hyperactivity disorder (ADHD) includes pharmacological, psychosocial and educational interventions. A custom designed treatment taking into account patient characteristics, type of disorder and comorbidity must be advisable. First election drugs are the psychostimulant methylphenidate (MTF) and the sympathomimetic not stimulant atomoxetine (ATX). These drugs reduce the clinical manifestations of restlessness, inattention and impulsivity, improving the quality of social relationships and academic performance. MTF blocks the presynaptic dopamine (DA) and norepinephrine (NA) transporters increasing the concentration of these neurotransmitters in the presynaptic neuron. Both of them are available in the pharmaceutical forms of immediate release (IR) (Rubifen ® and Medicebran®, prolonged acting preparations with OROS® [osmotic controlled-release oral delivery system] technology, Con certa® and Metilfenidato Sandoz®) and pellets (Medikinet®), allowing a proper selection of dosage pattern. IR pharmaceutical forms can induce rebounding effect by causing high plasma peak that decays quickly. ATX is a highly selective and a potent inhibitor of presynaptic NA transporter, increasing levels of NA and DA in the prefrontal cortex, but not in cortical regions related to the development of tics or risk of substance abuse. It can be an alternative to MTF when this loses effectiveness or is contraindicated. The effectiveness of both drugs must be considered after 2 to 4 weeks of treatment. Their side effects are numerous and often cause discomfort making diffi cult adherence. Therefore it is necessary to monitor these patients playing pharmacist a leading role in improving the performance and the effects of pharmacotherap

    Sustainable development program at the Faculty of Nautical Studies of Barcelona, Nautical engineering education

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    Nautical engineering education institutions play an important role and are a key tool in the future sustainable maritime transport and naval world. This paper addresses the role of nautical engineering education in the learning and implementation of the competence of sustainability and social commitment (SSC) in the Nautical Faculty of Barcelona and presents results of the first year of the implementation of the environmental program STEP2015 at the Universitat Politècnica de Catalunya.Postprint (published version

    Singular sources in the Demianski-Newman spacetimes

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    The analysis of singular regions in the NUT solutions carried out in the recent paper (Manko and Ruiz, 2005 Class. Quantum Grav. 22, p.3555) is now extended to the Demianski-Newman vacuum and electrovacuum spacetimes. We show that the effect which produces the NUT parameter in a more general situation remains essentially the same as in the purely NUT solutions: it introduces the semi-infinite singularities of infinite angular momenta and positive or negative masses depending on the interrelations between the parameters; the presence of the electromagnetic field additionally endows the singularities with electric and magnetic charges. The exact formulae describing the mass, charges and angular momentum distributions in the Demianski-Newman solutions are obtained and concise general expressions P_n=(m+i\nu)(ia)^n, Q_n=(q+ib)(ia)^n for the entire set of the respective Beig-Simon multipole moments are derived. These moments correspond to a unique choice of the integration constant in the expression of the metric function \omega which is different from the original choice made by Demianski and Newman.Comment: 22 pages, 5 figures; submitted to Classical and Quantum Gravit

    A template method to measure the tt polarisation

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    This work is supported by the Spanish Research Agency (Agencia Estatal de Investigacion) through the grant IFT Centro de Excelencia Severo Ochoa SEV-2016-0597, by the projects PID2019-110058GB-C21, PID2019-110058GB-C22 from MICINN/AEI/ERDF, and by projects CERN/FIS-PAR/0004/2019, CERN/FIS-PAR/0029/2019 from FCT. The work of P.M.R. is supported through the FPI grant BES-2016-076775. The work of M.C.N.F. was supported by the PSC-CUNY Awards 63096-00 51 and 64031-00 52.We develop a template method for the measurement of the polarisation of tt¯ pairs produced in hadron collisions. The method would allow to extract the individual fractions of tLt¯ L, tRt¯ R, tLt¯ R and tRt¯ L pairs with a fit to data, where L, R refer to the polarisation along any axis. These polarisation fractions have not been independently measured at present. Secondarily, the method also provides the net polarisation of t and t¯ , as well as their spin correlation for arbitrary axes.IFT Centro de Excelencia Severo Ochoa PID2019-110058GB-C21, PID2019-110058GB-C22, SEV-2016-0597PSC-CUNY 63096-00 51, 64031-00 52Spanish Research AgencyFamily Process Institute BES-2016-076775Ministerio de Ciencia e InnovaciónEuropean Regional Development Fund CERN/FIS-PAR/0004/2019, CERN/FIS-PAR/0029/2019Fundació Catalana de TrasplantamentAgencia Estatal de Investigació

    Red neuronal autorregresiva no lineal con entradas exógenas para la predicción del electroencefalograma fetal

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    [Resumen] Este artículo describe un algoritmo simple y robusto para la simulación de señales biomédica usando una red neuronal autorregresiva no lineal con entradas exógenas (NARX- nonlinear autorregresive network with exogenous inputs). La NARX puede ajustarse para sistemas dinámicos cuya salida depende tanto de la entrada recibida como del estado en que se encuentre el sistema. Por lo que es especialmente adecuada para la estimación de los componentes cuasi-periódico de las señales fisiológicas, tales como el Electroencefalograma (ECG). La validez y rendimiento del método descrito se confirman a través de experimentos sobre datos reales obtenidos de la base de datos de acceso público PhysioNet

    Framework para el modelado de un lago de datos

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    [Resumen] La necesidad de trabajar con grandes cantidades de datos para realizar clasificaciones, detectar patrones, identificar sistemas y predecir el comportamiento futuro de los mismos exige un entorno escalable que permita obtener el valor oculto en los datos. En este trabajo se presenta una pila formada por un almacén de datos, un visualizador y un gestor de flujos de trabajo para la ejecución de tareas, como marco general para el uso masivo de los datos. Siendo esta estructura general para cualquier dominio y formada por herramientas de software libre.Fundación CajaCanarias; nº2016TUR1

    Efecto de un programa de capacitación en competencias de investigación en estudiantes de ciencias de la salud

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    The European Higher Education Area implies a change to the Health Science education in Spain. Spanish university system must promote the acquisition of competences in research habits, such as the information management or scientific dissemination. This article presents the findings of a study to evaluate the level of effectiveness and satisfaction of an educational training program on research skills geared towards Health Science students. A hundred and eight students of Physical Therapy degree, Occupational Therapy degree and Nursing degree were participated into a quasi-experimental study. Educational needs were first detected by a questionnaire based on different research skills. A semi-distance educational training program was designed and implemented after defining the above-mentioned needs. This program significantly improved the perception of knowledge and skills in research competences. As well as the level of theory and practical content assimilated by the students significantly increased after the program. These findings suggest that incorporation of specific training that allow for students to come in contact with research, are effective at improving research competences for Health Sciences students.El Espacio Europeo de Educación Superior implica un cambio en la formación universitaria de Ciencias de la Salud en España. El sistema universitario debe promover desde el grado la adquisición de competencias básicas en investigación, como la gestión de información y la comunicación científica. Este artículo presenta los hallazgos de un estudio cuyo objetivo fue evaluar el nivel de eficacia y satisfacción de un programa de capacitación educativa en competencias de investigación dirigido a estudiantes de Ciencias de  la Salud. Se diseñó un estudio cuasiexperimental en el que participaron ciento ocho estudiantes de grado de Fisioterapia, Terapia ocupacional y Enfermería. En una primera fase se detectaron las necesidades educativas en competencias de investigación a través de un cuestionario; a continuación se implementó un programa de capacitación semipresencial y se evaluó el efecto alcanzado en las necesidades antes detectadas.  Este programa mejoró significativamente la percepción de los participantes en relación a su conocimiento y habilidad en competencias de investigación. Del mismo modo, las destrezas cognitivas y prácticas mejoraron considerablemente tras el programa. Estos hallazgos evidencian que la puesta en marcha de programas específicos de capacitación en investigación es efectiva para mejorar la adquisición de competencias a este respecto en estudiantes de Ciencias de la Salud

    Impact of Implementing a Dyslipidemia Management Guideline on Cholesterol Control for Secondary Prevention of Ischemic Heart Disease in Primary Care

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    Cardiovascular diseases (CVD) are the main cause of death worldwide. The control of CVD risk factors, such as dyslipidemia, reduces their mortality rate. Nonetheless, fewer than 50% of patients with ischemic heart disease (IHD) have good cholesterol control. Our objective is to assess whether the level of participation of general practitioners (GPs) in activities to implement a dyslipidemia management guideline, and the characteristics of the patient and physician are associated with cholesterol control in IHD patients. We undertook a quasi-experimental, uncontrolled, before-and-after study of 1151 patients. The intervention was carried out during 2010 and 2011, and consisted of a face-to-face training and online course phase (Phase 1), and another of face-to-face feedback (Phase 2). The main outcome variable was the low-density lipoprotein cholesterol (LDL-C) control, whereby values of <100 mg/dL (2.6 mmol/L) were set as a good level of control, according to the recommendations of the guidelines in force in 2009. After Phase 1, 6.7% more patients demonstrated good cholesterol control. With respect to patient characteristics, being female and being older were found to be risk factors of poor control. Being diabetic and having suffered a stroke were protective factors. Of the GPs' characteristics, being tutor in a teaching center for GP residents and having completed the online course were found to be protective factors. We concluded that cholesterol control in IHD patients was influenced by the type of training activity undertook by physicians during the implementation of the GPC, and patient and physician characteristics. We highlight that if we apply the recent targets of the European guideline, which establish a lower level of LDL-C control, the percentage of good control could be worse than the observed in this study
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