Laser radiation as an adjunct to nonsurgical treatment of periodontal disease.

Peer Reviewe

Surface and core detonations in rotating white dwarfs

The feasibility of the double detonation mechanism—surface helium detonation followed by complete carbon detonation of the core—in a rotating white dwarf with mass ;1Me is studied using three-dimensional hydrodynamic simulations. A rapid rigid rotation of the white dwarf was assumed, so that its initial spherical geometry is considerably distorted. Unlike spherically symmetric models, we found that when helium ignition is located far from the spinning axis, the detonation fronts converge asynchronically at the antipodes of the ignition point. Nevertheless, the detonation of the carbon core still remains as the most probable outcome. The detonation of the core gives rise to a strong explosion, matching many of the basic observational constraints of Type Ia supernovae (SNe Ia). We conclude that the double detonation mechanism also works when the white dwarf is rapidly rotating. These results provide further evidence for the viability of sub-Chandrasekhar-mass models as well as some double degenerate models (those having some helium fuel at the merging moment), making them appealing channels for the production of SN Ia events.Peer ReviewedPostprint (published version

Modulation of Dendritic Cell Responses by Parasites: A Common Strategy to Survive

Parasitic infections are one of the most important causes of morbidity and mortality in our planet and the immune responses triggered by these organisms are critical to determine their outcome. Dendritic cells are key elements for the development of immunity against parasites; they control the responses required to eliminate these pathogens while maintaining host homeostasis. However, there is evidence showing that parasites can influence and regulate dendritic cell function in order to promote a more permissive environment for their survival. In this review we will focus on the strategies protozoan and helminth parasites have developed to interfere with dendritic cell activities as well as in the possible mechanisms involved

QGOLF-9 : Escala para la evaluación de la calidad percibida en los clubes de golf

The assessment of perceived quality has become important in the management of service providing organizations. The aim of this paper is to develop a brief, easy-to-apply scale with appropriate psychometric properties, which allows the incorporation of users' perceptions of the management of golf clubs. We interviewed 403 users of four 9-hole course golf clubs located in Galicia (316 males and 87 females) aged between 16 and 75 years (Mean = 47.19; SD = 13.91). For data collection, an ad hoc structured questionnaire which had 25 items grouped into 4 dimensions was used. As a result of Exploratory Factor Analysis and a subsequent Confirmatory Factor Analysis, it was possible to obtain a final scale made up of only 15 items, grouped into three dimensions. This scale, as well as being brief and easy-to-apply, has a high degree of validity (as it explains 72% of the perceived performance) and internal consistency (overall a of .91), thus making it a tool of considerable applied interest.La evaluación de la calidad percibida ha cobrado una gran importancia en la gestión de las organizaciones de prestación de servicios. El objetivo de este trabajo es desarrollar una escala con propiedades psicométricas adecuadas, breve y de fácil aplicación que permita incorporar las percepciones de los usuarios a la gestión de los clubes de golf. Fueron entrevistados 403 usuarios de 4 clubes de golf con campos de 9 hoyos ubicados en Galicia (316 hombres y 87 mujeres), con edades comprendidas entre los 16 y 75 años (Media = 47.19; DE = 13.91). Para la recogida de datos se utilizó un cuestionario estructurado ad hoc que contaba con 25 elementos agrupados en 4 dimensiones. Fruto de un Análisis Factorial Exploratorio inicial y de un Análisis Factorial Confirmatorio posterior, ha sido posible obtener una escala final compuesta por tan solo 15 ítems agrupados en tres dimensiones. Dicha escala, además de ser breve y de fácil aplicación, posee un alto grado de validez de criterio (ya que explica el 72% del desempeño percibido del club) y una elevada consistencia interna (con un a global de .91), lo que la convierte en una herramienta de notable interés aplicado

Characterization of Profiles as Management Strategies Based on the Importance and Valuation That Users Give to the Elements of the Golf Courses

The main objective of this study was to characterize golfers’ profiles based on the importance and valuation that users give to the elements of golf courses, considering the segmentation as key to making strategic decisions. This was done using a priori segmentation of the traditional style against a post hoc segmentation based on the importance that users concede to variability of elements of golf courses. Moreover, the relationship between the quality attributed to the service dimensions and the golf course global performance was examined for each of the obtained segments. The results have established certain specific characteristics of the typical golf user and two large segments of golfers were identified from Cluster Analysis (Competitives and Socials), they were made up of the following subgroups: Regular-leisure and business and matures-familiar. The causal analysis of covariance structures for each segment revealed partially different interests. This study provides useful information for managers to design management strategies that address the different characteristics, interests, and priorities of their customers and potential customers in order to win them, keep them, satisfy them, and build their loyalty, ensuring the development and sustainability of the entityS

Creación de un Modelo de Formación para la Convivencia Escolar mediante mecanismos de la gestión del conocimiento

Este documento presenta la intervención realizada en una escuela con el propósito de generar cambios en la cultura escolar, especialmente en la convivencia de su comunidad inmediata, a través de mecanismos de la gestión del conocimiento. Se expone cómo la necesidad de manejar la disciplina en la escuela derivó en una serie de acciones que permitieron la formación de una comunidad de práctica, la cual asumió la misión de construir una propuesta de intervención que cubriera esta necesidad. El proyecto tuvo el objetivo de crear un Modelo de Formación para la Convivencia Escolar que dirigiera las acciones de la escuela a la formación de los alumnos no sólo en lo académico, sino en lo social y humano. Uno de los primeros pasos y en el cual se centró la intervención, fue en convertir a los profesores en diseñadores de estrategias que pudieran fomentar la convivencia escolar. Con este proceso, se inició una transformación en la cultura escolar que comenzó con nuevas configuraciones en el trabajo. Uno de los resultados fue el incremento de la participación de los profesores en asuntos relacionados con la convivencia, la disciplina y el manejo del grupo, lo que refleja un mayor compromiso del docente y su identificación como protagonista en la formación integral del alumno

PrimPol, una nueva primasa/polimerasa en células humanas

Tesis doctoral inédita, leída en Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Biología Molecular. Fecha de lectura: 17/07/2013En esta Tesis Doctoral se presenta la purificación y caracterización enzimática de una nueva primasa humana de la superfamilia AEP (primasas arqueo eucariotas). Ccdc111 había sido identificada como un miembro potencial de la superfamilia AEP mediante comparaciones de secuencia de aminoácidos. El gen CCDC111 humano fue subclonado, y la proteína ccdc111 fue sobre-expresada de forma heteróloga en Escherichia coli. Ccdc111 fue estabilizada por adición de una cola de histidinas en su extremo amino, lo que posteriormente ayudó a su purificación mediante columnas de afinidad. Se pudo obtener una fracción pura y en concentración suficiente para realizar un detallado análisis enzimático. En este trabajo se demuestra que, en efecto, ccdc111 posee actividad RNA primasa por ser capaz de utilizar ribonucleótidos para la síntesis de iniciadores (como las primasa convencionales), pero también que es capaz de hacerlo a partir de deoxirribonucleótidos, por lo que posee actividad DNA primasa. El estudio en detalle de su actividad primasa ha revelado que ccdc111 tiene la misma afinidad por los NTPs que por los dNTPs como sustratos del sitio 5´ o sitio de iniciación. Sin embargo, presenta una preferencia 100 veces mayor por utilizar dNTPs para el sitio 3´ o sitio de elongación. Con respecto a la distinción de determinadas secuencias como señal de reconocimiento y comienzo de la síntesis de iniciadores, ccdc111 reconoce un trímero formado por: una Guanina en primera posición, como nucleótido críptico (que es reconocido pero no copiado); una Pirimidina en segunda posición, de modo que empieza la síntesis usando una purina (fisiológicamente más abundantes) y un tercer nucleótido sobre el que no se ha detectado especial predilección. Ccdc111 fue capaz de elongar un iniciador pre-existente, demostrando que posee, además, actividad DNA y RNA polimerasa. Debido a la dualidad de ccdc111 como primasa y polimerasa, se modificó su nomenclatura (aprobada por el comité HUGO), llamándose ahora PrimPol. Se identificaron los residuos responsables de la catálisis en el centro activo de PrimPol, tanto de su actividad primasa como de su actividad polimerasa. PrimPol es una DNA polimerasa distributiva, que inserta dNTPs siguiendo el dictado de una cadena molde con unos niveles moderados de fidelidad, a pesar de carecer de actividad correctora de errores. Además, PrimPol polimeriza eficientemente a través de lesiones en el DNA como el 8oxoG, los sitios abásicos, o los dímeros de timinas (del tipo CPD), entre otros daños en el DNA. Estos resultados apoyan la función de PrimPol en tolerancia al daño durante la replicación de DNA. PrimPol posee un dominio dedo de zinc en su extremo C-terminal, que es esencial para la actividad primasa. Sin embargo, el dedo de zinc resulta ser no solo prescindible para su actividad polimerasa, sino que su eliminación incrementa la eficiencia de polimerización, disminuyendo la KM por los dNTPs. Estudios de locación subcelular revelaron que PrimPol se encuentra tanto en el núcleo como en la mitocondria. PrimPol podría estar ejerciendo una función auxiliar durante la replicación del DNA nuclear llevada a cabo por Polε y Polδ, y del DNA mitocondrial por Polγ. PrimPol asistiría a las DNA polimerasas replicativas de ambos compartimentos celulares, que se hubieran detenido frente a una lesión en el DNA molde, actuando como DNA polimerasa de translesión o sintetizando nuevos iniciadores cerca de la lesión, permitiendo así la progresión de la horquilla de replicación.This Doctoral Thesis reports the purification and biochemical characterization of a novel human primase belonging to the AEP (Archeo Eukaryotic Primases) superfamily. Ccdc111 had been identified as a putative AEP new member by amino acid sequence comparisons. The human gen CCDC111 was cloned, and ccdc111 was overexpressed in Escherichia coli. Ccdc111 was stabilized by adding a histidine tag at its N-terminus, that also facilitated purification through affinity columns. Both the purity achieved and the high yield obtained, allowed a detailed enzymatic analysis of ccdc111 This work shows that, in fact, ccdc111 has RNA primase activity, as it is able to use ribonucleotides to make primers (as conventional primases do), but strikingly, it can initiate synthesis from deoxynucleotides, thus being also a DNA primase. The detailed study of its primase activity demonstrated that ccdc111 has the same affinity for NTPs than for dNTPs as substrates for the 5´ site (initiation site); however, ccdc111 displays a 100 higher preference for dNTPs at the 3´ site (elongation site). Among the specific template sequences preferred to initiate primer synthesis, ccdc111 recognizes a trinucleotide consisting in: a guanine at the first position, as a cryptic nucleotide (that is recognized but not copied); a pyrimidine at the second position, dictating the start with a purine nucleotide (physiologically more abundant); and any of the four dNTPs at the third position. Ccdc111 was able to elongate a pre-existing primer, also demonstrating DNA and RNA polymerase activities. Such a duality of ccdc111 as a primase and polymerase, prompted us to modify its name to PrimPol (approved by the HUGO committee) The catalytic residues forming a common active site responsible for both primase and polymerase activities of PrimPol have been identified. PrimPol is a distributive DNA polymerase, that inserts dNTPs by copying a template chain with a moderate fidelity, in spite of the lack of proofreading activity. Moreover, PrimPol tolerates lesions in the template strand as 8oxoG, abasic sites, or thymidine dimers (CPD), to name a few. These results support a role of PrimPol in damage tolerance coupled to DNA replication. PrimPol has a zinc finger domain at its C-terminus, shown to be crucial for the primase activity. Strikingly, the zinc finger domain is not only dispensable for the polymerase activity of PrimPol, but its deletion does enhance polymerization efficiency by decreasing the KM for dNTPs. Subcellular localization analysis showed that PrimPol is present at both nucleus and mitochondria. PrimPol could have an auxiliary role during nuclear DNA replication by Polε y Polδ; and during mitochondrial DNA replication by Polγ. PrimPol would assist replicative DNA polymerases from both compartments, when they become stalled opposite DNA lesions, by acting as a translesion synthesis polymerase or by synthesizing a new primer near the lesion allowing the progression of the replication fork

EVALUATION OF THE COST-EFFECTIVENESS OF GRID-CONNECTED PHOTOVOLTAIC SOLAR ENERGY IN WINERIES

The objective of this study was to analyze the cost-effectiveness of photovoltaic (PV) solar energy in wineries. The factors analysed were solar radiation, cost of PV installation, prices in the public electricity grid, size of the winery, power of installed panels, influence of the decreased consumption during weekends, and seasonality in the consumption. The study has been based on the European TESLA project, in which 39 energy audits were carried out in wineries in four European countries. A winery of 30,000 hL/year was characterized as a representative winery. The results showed that seasonality was key in the profitability of the system for self-consumption, related to the optimum power to be installed of PV. It was recommended to install, as an optimal PV power, the stable electrical power that is demanded in the daytime period. Optimizing the installed power of PV panels in the representative winery, the percentage of electrical energy consumption covered by photovoltaic energy varied between 16% and 22%. The percentage of the cost of electric energy covered varied between 18% and 24%, with payback values between 18 years (3.1 peak sun hours of solar radiation -PSH) and 10 years (5.6 peak sun hours of solar radiation - PSH). All the factors involved were analyzed

Childhood participation experiences in the memory

This article is based on the findings of a broader research project entitled 'Childhood Participation and Citizenship Building', which examined the medium-term effects of intense experiences of participation in childhood within both the school environment and those of leisure-time and community education. The results presented in this article refer specifically to the memories subjects hold of their participation in these childhood experiences. The study combined quantitative (using a questionnaire) and qualitative approaches (conducting in-depth interviews). The results obtained contribute to strengthening the idea explicit or implicit in all pedagogies that seek to promote child participation that such participation is not only a right, but that it also contributes to the quality of educational experiences