La lectura y los trastornos en su aprendizaje

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FleN and FlhF as new regulatory elements in the lifestyle switch in Pseudomonas putida

Motivation:Pseudomonas putida is a soil bacterium that can be found in nature as individual motile cells or as part of sessile communities called biofilms (1). Biofilm formation could be considered an adaptive strategy as it provide higher resistance against adverse agents, antimicrobial treatments, ultraviolet radiation or dehydration, increasing bacteria survival (2). The switch from a planktonic lifestyle to biofilm formation in P.putida is regulated by FleQ and the intracellular levels of c-di-GMP (3). Isolation of insertion mutants in flhF gene, defective in biofilm formation, suggests the involvement of additional elements in the regulation of this process. In this work, we have characterized the transcriptional organization of flhA, flhF, fleN and fliA genes and the role of FlhF and FleN in biofilm development in P.putida. Methods: Planktonic growth and biofilm formation curves, adhesion and swimming-motility assays. Gene expression analysis: β-galactosidase assays and RT-PCR. Electrophoretic mobility shift assays (EMSA).Results and Conclusions: To test the role of FlhF and FleN in biofilm development, we carried out a phenotypic characterization of ΔflhF and ΔfleN mutants. Experiments shown that ΔfleN mutant is not able to form biofilm whereas ΔflhF mutant exhibits a wild-type phenotype. Adhesion assays indicate that ΔfleN mutant has a reduced adhesion, whereas ΔflhF can properly adhere to the surface. On the other hand, both mutant show reduced swimming motility. These resuts suggests that both, FleN and FlhF, are involved in swimming motility, but only FleN is necessary for biofilm formation, probably by altering adhesion capacity of the bacteria. Bioinformatic tools predict that flhF and fleN form an operon with the upstream gene flhA and the downstream gene fliA. In order to corroborate this hypothesis, we have done RT-PCR using RNA from the mutants. Results shown that these genes are structured in a single operon: flhAFfleNfliA.To determine a possible regulatory role of these elements in biofilm formation and motility, β-galactosidase assays were performed to analyse the expression of biofilm and flagellum related promoters. Results shown that FleN downregulates both types of promoters whereas FlhF is only involved in the regulation of one flagellar gene. The regulatory role of FleN has been further studied in vitro by EMSA with the regulator FleQ. Results suggest that FleN is required for FleQ to bind to its target promoters

Safeguarding Health at the Workplace: A Study of Work Engagement, Authenticity and Subjective Wellbeing among Religious Workers

: Research in work and organizational psychology has paid little attention to religious workers, something certainly surprising as faith-based organizations play a key role in the welfare state of many countries. This research shows that religious workers in a Catholic order present a high degree of subjective wellbeing, both in terms of flourishing and satisfaction with life in general, and a positive balance of positive and negative feelings. More specifically, this study examines the relationship between authenticity and wellbeing amongst religious workers. Survey responses from 142 religious workers in Spain were analyzed using partial least squares path modelling. The results reveal that subjective wellbeing at work is positively related to authenticity. In addition, this relationship is mediated by their level of work engagement

The Subjective Well-Being Challenge in the Accounting Profession: The Role of Job Resources

The main activity of the accountant is the preparation and audit of the financial information of a company. The subjective well-being of the accountant is important to ensure a balanced professional judgment and to offer a positive image of the profession in the face of the incorporation and retention of talent. However, accountants are subjected to intense pressures that affect their well-being in the performance of their tasks. In this paper, the job demands–resources theoretical framework is adopted to analyze the relationships between job demands, job resources, and the subjective well-being of a large sample of 739 accounting experts at the European level. Applying a structural equations model, the results confirm, on the one hand, the direct effects provided in the theoretical framework and, on the other, a new mediating role of job demands–subjective well-being relationship resources

Contraste de los riesgos valorados para los tipos de tarjetas que han sido utilizadas como medio de pago en el sistema integrado de transporte público

Trabajo de InvestigaciónEl sistema integrado de transporte público SITP, es uno de los sistemas más grandes y sofisticados de transporte en Colombia; el ingreso a este se hace mediante tarjetas inteligentes sin contacto entre las cuales se encuentran: tarjeta monedero, cliente frecuente y tullave bajo la licitación de recaudo Bogotá. Debido a diferentes sucesos presentados, vulneración del medio de pago, se realizó una valoración de riesgos por medio de la norma ISO 27005,seguridad de la información de activos, basándose en la identificación de amenazas, vulnerabilidades y riesgos de las tarjetas utilizadas en el sistema.RESUMEN ABSTRACT INTRODUCCIÓN 1. GENERALIDADES 2. ESTABLECIMIENTO DEL CONTEXTO 3. IDENTIFICACIÓN DE RIESGOS 4. ESTIMACIÓN DE RIESGOS 5. EVALUACIÓN DE RIESGOS 6. CONCLUSIONES 7. RECOMENDACIONES Y TRABAJOS FUTUROS 8. ANEXOS 9. REFERENCIASPregradoIngeniero de Sistema

El paradigma para investigar en ciencias de lo fiscal y lo económico

Discusión teórica al respecto del paradigma adecuado para el análisis de los temas fiscales y económicos

Generación de mallas triangulares simplificadas empleando la Red Neuronal de Kohonen

RESUMENLas mallas triangulares, son una de las técnicas más utilizadas en la generación de modelos computacionales de superficies de objetos 3D; aunque el proceso de generación de éstas, implica tratar con dos problemas: la determinación de la conectividad entre los puntos de datos, y el costo computacional tanto del procesamiento de los mismos, como del almacenamiento de su representación. Encontrar una técnica que genere representaciones triangulares aceptables con bajos costos computacionales, se reduce a la selección de un conjunto de puntos menor al conjunto original de datos, que sean representativos de la topología de la superficie, de tal forma que la densidad de puntos varíe en regiones según el grado de curvatura, permitiendo mayor densidad de puntos en regiones con alto nivel de curvatura, e inversamente a ésto, baja densidad de puntos en regiones con topologías poco curvadas. Este artículo presenta un método de reducción y determinación de conectividad de datos de rango, para la generación de mallas triangulares sobre superficies de objetos 3D, empleando mapas auto-asociativos de Kohonen. A la red de Kohonen se le presentan los puntos de datos como patrones de entrada, la cual luego del entrenamiento, los aproxima con los vectores de pesos de sus neuronas. Los vecindarios de neuronas determinan la conectividad del nuevo conjunto de datos

Spatial distribution and intra-annual variability of water masses on the Eastern Gulf of Cadiz seabed

This paper presents the spatial distribution and intra-annual variability of seabed hydrography in the Eastern Gulf of Cadiz based on more than 10 years of near-bottom CTD observations. Well-defined water masses and a variety of mixing products are persistently sorted along three bathymetric areas occupying particular depth intervals: (i) inner shelf waters (<60 m depth), with strong coastal and atmospheric influence; (ii) low-salinity Eastern North Atlantic Central Waters (ENACW) related to the Gulf of Cadiz Current (GCC) along the central and outer shelf (between 100 and 250 m depth); and (iii) a range of salinity and temperature flavors associated with the dense Mediterranean Outflow Water (MOW) occupying the deeper grounds. All three are characterized by significant March– November hydrographic differences suggesting an intra-annual variability pattern. After summer heating and stratification of the water column, warm (17.8 °C) and saline (36.26) waters occupy the inner-shelf in November whereas cooler (14.6 °C) and less saline (36.17) waters occur in March as the combined result of the erosion of the seasonal thermocline and intensified continental runoff. Offshore, colder, more saline and hence denser MOW invades the upper slope in March diluting the easternmost tip of a saltier ENACW wedge and nudging its outer rim up onto the shelf. This narrows and constricts the GCC band in winter, while its bottom trace appears to broaden and stretch eastwards in November. More effective MOW-ENACW mixing west of the Strait of Gibraltar driven both by an elevated MOW and a less stratified ENACW could explain the winter salinification of most of the grounds deeper than 250 m.En prensa2,088