128 research outputs found

    Diacritical study of light, electrons, and sound scattering by particles and holes

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    We discuss the differences and similarities in the interaction of scalar and vector wave-fields with particles and holes. Analytical results are provided for the transmission of isolated and arrayed small holes as well as surface modes in hole arrays for light, electrons, and sound. In contrast to the optical case, small-hole arrays in perforated perfect screens cannot produce acoustic or electronic surface-bound states. However, unlike electrons and light, sound is transmitted through individual holes approximately in proportion to their area, regardless their size. We discuss these issues with a systematic analysis that allows exploring both common properties and unique behavior in wave phenomena for different material realizations.Comment: 3 figure

    El portafolios reflexivo como instrumento didáctico en la práctica clínica de la enfermería materno-infantil. Póster

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    [SPA]Con el Espacio Europeo de Educación Superior, la necesidad de conocer datos acerca de cómo trabaja el estudiante es cada vez mayor, desde la UNESCO, se nos viene pidiendo que formemos ciudadanos bien informados y profundamente motivados, provistos de un sentido crítico. Disponemos de una herramienta didáctica que se ajusta a estos objetivos: el portafolio reflexivo. Este instrumento se presenta como una alternativa a las estrategias de evaluación tradicionales. Se basa en la negociación y en el intercambio comunicativo entre el profesor y el estudiante, acerca de los criterios para su evaluación. Hace al alumno ser consciente de su progreso en el aprendizaje lo que repercute en una formación más cualitativa. En este estudio presentamos los resultados obtenidos en una experiencia en la que se utiliza el portafolio reflexivo del alumno, con el objetivo de evaluar la efectividad de este instrumento durante el periodo de prácticas clínicas de un grupo de alumnos de 3º de la Facultad de Enfermería de Murcia. Pudiendo concluir que esta metodología docente resulta muy útil para profesor y alumno, aumentando el aprendizaje, mejorando las relaciones entre grupos y la transmisión del conocimiento y posibilitando una evaluación global eficaz y un desarrollo formativo de garantía. [ENG]With The European Higher Education Area (EHEA), the necessity of knowing data about how a student works is increasing. From UNESCO, we have been asked to form well-informed and deeply motivated citizens, provided with a critical sense. We have a didactic tool that meets these objectives: the reflexive portfolio. This tool is presented as an alternative to the traditional evaluation strategies. It is based on the negotiations and the communicative exchanges between the teacher and the student, concerning the criteria about the evaluation. This makes the student to be aware of his learning progress what is reflective in a more qualitative training. In this study, it is presented the results obtained in a specific experience in which the student´s reflexive portfolio has been used, which aim is to assess the effectiveness of the tool during the period of clinical practices with a student group at University (3rd Year Facultad de Enfermería de Murcia). Concluding, it could be said that this is a very useful methodology for both teacher and student, increasing learning, improving the relationships among groups and the transmission of knowledge, providing a global evaluation and a warranty formative development.Campus Mare Nostrum, Universidad Politécnica de Cartagena, Universidad de Murcia, Región de Murci

    MicroRNA-mediated differential expression of TRMU, GTPBP3 and MTO1 in cell models of mitochondrial-DNA diseases

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    Mitochondrial diseases due to mutations in the mitochondrial (mt) DNA are heterogeneous in clinical manifestations but usually include OXPHOS dysfunction. Mechanisms by which OXPHOS dysfunction contributes to the disease phenotype invoke, apart from cell energy deficit, maladaptive responses to mitochondria-to-nucleus retrograde signaling. Here we used five different cybrid models of mtDNA diseases to demonstrate that the expression of the nuclear-encoded mt-tRNA modification enzymes TRMU, GTPBP3 and MTO1 varies in response to specific pathological mtDNA mutations, thus altering the modification status of mt-tRNAs. Importantly, we demonstrated that the expression of TRMU, GTPBP3 and MTO1 is regulated by different miRNAs, which are induced by retrograde signals like ROS and Ca2+ via different pathways. Our data suggest that the up- or down-regulation of the mt-tRNA modification enzymes is part of a cellular response to cope with a stoichiometric imbalance between mtDNA- and nuclear-encoded OXPHOS subunits. However, this miRNA-mediated response fails to provide full protection from the OXPHOS dysfunction; rather, it appears to aggravate the phenotype since transfection of the mutant cybrids with miRNA antagonists improves the energetic state of the cells, which opens up options for new therapeutic approaches

    Zulassigkeit der schriftlichen Zeugenvernehmung(III)

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    In this letter, we investigate the optical properties of packed monodisperse silica submicron spheres by means of optical transmission measurements. The results are compatible with a three dimensional face centered cubic order in these solid structures. The lattice parameter of these structures, and therefore their optical properties, can be easily tuned through the sphere size (between 200 and 700 nm) thus covering the whole visible and near infrared spectrum.Comisión Interministerial de Ciencia y Tecnología MAT94-072

    Impacto de las recomendaciones sobre la vacunación de hepatitis A en niños de familias inmigrantes de países de alta endemia residentes en Castellón

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    Introducción: Los hijos de inmigrantes procedentes de países de alta endemia de hepatitis A que viajan para visitar a sus familiares, forman un grupo al que se recomienda la vacunación previa al viaje. En el Departamento de La Plana (Castellón), a finales de noviembre de 2012, hubo un aumento de casos de hepatitis A en niños que regresaban del viaje de su país de origen (Marruecos). Se realizaron actuaciones para promocionar la vacunación de estos niños antes de los viajes a su país en la primavera/verano de 2013. Objetivo: Evaluar el impacto de estas recomendaciones. Métodos: Estudio retrospectivo observacional comparativo usando datos del Registro de Vacunas. Se compararon los periodos previo y posterior a la intervención. Resultados: Hubo un aumento en el número de niños vacunados (de 33 a 263). El mayor incremento se observó en niños origen magrebí del Departamento de La Plana (pasó de 2 a 139). En este Departamento se estimó una cobertura del 17%. Conclusiones: Las medidas adoptadas tuvieron un impacto moderado. La cobertura sigue siendo baja. Conviene insistir en la vacunación preexposición de estos niños. Deben implicarse los servicios de salud pública, atención primaria, vacunación internacional y escolares

    Mucus extravasation and retention phenomena: a 24-year study

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    <p>Abstract</p> <p>Background</p> <p>Mucoceles are benign lesions related to the minor salivary glands and their respective ducts frequently affecting oral structures which are generally asymptomatic. Mucoceles are generally characterized by swollen nodular lesions preferentially located on the lower lip and differ from the so-called ranulas, which are lesions located on the floor of the mouth and related to the sublingual or submandibular glands.</p> <p>Methods</p> <p>The objective of the present study was to analyze data such as age, gender, race and site of the lesion of 173 mucocele cases diagnosed at the Discipline of Stomatology, São José dos Campos Dental School, UNESP, over a period of 24 years (April 1980 to February 2003).</p> <p>Results</p> <p>Of the 173 cases analyzed, 104 (60.12%) were females and 69 (39.88%) were males. Age ranged from 4 to 70 years (mean ± SD: 17 ± 9.53) and most patients were in the second decade of life (n = 86, 49.42%); white (n = 124, 71.68%). The lower lip was the site most frequently affected by the lesions (n = 135, 78.03%), whereas the lowest prevalence was observed for the soft palate, buccal mucosa, and lingual frenum.</p> <p>Conclusion</p> <p>In this study, mucoceles predominated in white female subjects in the second decade of life, with the lower lip being the most frequently affected site.</p

    Definition of a temporal distribution index for high temporal resolution precipitation data over Peninsular Spain and the Balearic Islands: the fractal dimension; and its synoptic implications

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    Precipitation on the Spanish mainland and in the Balearic archipelago exhibits a high degree of spatial and temporal variability, regardless of the temporal resolution of the data considered. The fractal dimension indicates the property of self-similarity, and in the case of this study, wherein it is applied to the temporal behaviour of rainfall at a fine (10-min) resolution from a total of 48 observatories, it provides insights into its more or less convective nature. The methodology of Jenkinson & Collison which automatically classifies synoptic situations at the surface, as well as an adaptation of this methodology at 500 hPa, was applied in order to gain insights into the synoptic implications of extreme values of the fractal dimension. The highest fractal dimension values in the study area were observed in places with precipitation that has a more random behaviour over time with generally high totals. Four different regions in which the atmospheric mechanisms giving rise to precipitation at the surface differ from the corresponding above-ground mechanisms have been identified in the study area based on the fractal dimension. In the north of the Iberian Peninsula, high fractal dimension values are linked to a lower frequency of anticyclonic situations, whereas the opposite occurs in the central region. In the Mediterranean, higher fractal dimension values are associated with a higher frequency of the anticyclonic type and a lower frequency of the advective type from the east. In the south, lower fractal dimension values indicate higher frequency with respect to the anticyclonic type from the east and lower frequency with respect to the cyclonic type

    The Spanish Infrared Camera onboard the EUSO-BALLOON (CNES) flight on August 24, 2014

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    The EUSO-Balloon (CNES) campaign was held during Summer 2014 with a launch on August 24. In the gondola, next to the Photo Detector Module (PDM), a completely isolated Infrared camera was allocated. Also, a helicopter which shooted flashers flew below the balloon. We have retrieved the Cloud Top Height (CTH) with the IR camera, and also the optical depth of the nonclear atmosphere have been inferred with two approaches: The first one is with the comparison of the brightness temperature of the cloud and the real temperature obtained after the pertinent corrections. The second one is by measuring the detected signal from the helicopter flashers by the IR Camera, considering the energy of the flashers and the location of the helicopter

    Reduced levels of intracellular calcium releasing in spermatozoa from asthenozoospermic patients

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    <p>Abstract</p> <p>Background</p> <p>Asthenozoospermia is one of the most common findings present in infertile males characterized by reduced or absent sperm motility, but its aetiology remains unknown in most cases. In addition, calcium is one of the most important ions regulating sperm motility. In this study we have investigated the progesterone-evoked intracellular calcium signal in ejaculated spermatozoa from men with normospermia or asthenozoospermia.</p> <p>Methods</p> <p>Human ejaculates were obtained from healthy volunteers and asthenospermic men by masturbation after 4–5 days of abstinence. For determination of cytosolic free calcium concentration, spermatozoa were loaded with the fluorescent ratiometric calcium indicator Fura-2.</p> <p>Results</p> <p>Treatment of spermatozoa from normospermic men with 20 micromolar progesterone plus 1 micromolar thapsigargin in a calcium free medium induced a typical transient increase in cytosolic free calcium concentration due to calcium release from internal stores. Similar results were obtained when spermatozoa were stimulated with progesterone alone. Subsequent addition of calcium to the external medium evoked a sustained elevation in cytosolic free calcium concentration indicative of capacitative calcium entry. However, when progesterone plus thapsigargin were administered to spermatozoa from patients with asthenozoospermia, calcium signal and subsequent calcium entry was much smaller compared to normospermic patients. As expected, pretreatment of normospermic spermatozoa with both the anti-progesterone receptor c262 antibody and with progesterone receptor antagonist RU-38486 decreased the calcium release induced by progesterone. Treatment of spermatozoa with cytochalasin D or jasplakinolide decreased the calcium entry evoked by depletion of internal calcium stores in normospermic patients, whereas these treatments proved to be ineffective at modifying the calcium entry in patients with asthenozoospermia.</p> <p>Conclusion</p> <p>Our results suggest that spermatozoa from asthenozoospermic patients present a reduced responsiveness to progesterone.</p

    From community approaches to single-cell genomics: the discovery of ubiquitous hyperhalophilic Bacteroidetes generalists

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    The microbiota of multi-pond solar salterns around the world has been analyzed using a variety of culture-dependent and molecular techniques. However, studies addressing the dynamic nature of these systems are very scarce. Here we have characterized the temporal variation during 1 year of the microbiota of five ponds with increasing salinity (from 18% to >40%), by means of CARD-FISH and DGGE. Microbial community structure was statistically correlated with several environmental parameters, including ionic composition and meteorological factors, indicating that the microbial community was dynamic as specific phylotypes appeared only at certain times of the year. In addition to total salinity, microbial composition was strongly influenced by temperature and specific ionic composition. Remarkably, DGGE analyses unveiled the presence of most phylotypes previously detected in hypersaline systems using metagenomics and other molecular techniques, such as the very abundant Haloquadratum and Salinibacter representatives or the recently described low GC Actinobacteria and Nanohaloarchaeota. In addition, an uncultured group of Bacteroidetes was present along the whole range of salinity. Database searches indicated a previously unrecognized widespread distribution of this phylotype. Single-cell genome analysis of five members of this group suggested a set of metabolic characteristics that could provide competitive advantages in hypersaline environments, such as polymer degradation capabilities, the presence of retinal-binding light-activated proton pumps and arsenate reduction potential. In addition, the fairly high metagenomic fragment recruitment obtained for these single cells in both the intermediate and hypersaline ponds further confirm the DGGE data and point to the generalist lifestyle of this new Bacteroidetes group.This work was supported by the projects CGL2012-39627-C03-01 and 02 of the Spanish Ministry of Economy and Competitiveness, which were also co-financed with FEDER support from the European Union. TG group research is funded in part by a grant from the Spanish Ministry of Economy and Competitiveness (BIO2012-37161), a grant from the Qatar National Research Fund grant (NPRP 5-298-3-086) and a grant from the European Research Council under the European Union’s Seventh Framework Programme (FP/2007-2013)/ERC (grant agreement no. ERC-2012-StG-310325)
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