1000 resultados para Universitat de Barcelona. Biblioteca. Manuscrit. 4


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La sífilis es una enfermedad de transmisión sexual (ETS) producida por el Treponema pallidum, que infecta principalmente a seres humanos y que es capaz de invadir casi cualquier órgano del cuerpo. Su infección facilita la transmisión de otras ETS. Desde finales de la última década hasta la actualidad, han ido apareciendo sucesivos brotes de sífilis en la mayor parte de países de la Europa Occidental. La sífilis, junto con otras ETS, es una enfermedad de declaración obligatoria en los países de la Unión Europea. Concretamente en España, la infonnación epidemiológica a nivel estatal se obtiene a través del Sistema de Enfemledades de Declaración Obligatoria (EDO) y del Sistema de Información Microbiológica (SIM), que recopila infonnación de una red de 46 laboratorios centinela situados en 12 Comunidades Autónomas. Las ETS sometidas a vigilancia epidemiológica son la infección gonocócica, la sífilis y la sífilis congénita, todas ellas de declaración numérica semanal. Con esta información se ha podido apreciar en los últimos años un incremento en los casos de sífilis y gonococia notificados en España (las tasas de sífilis por 100.000 habitantes en el año 1999 fueron de 1,69 y en el 2007 de 4,38 notificadas al sistema EDO). En este artículo revisamos el resurgimiento y la evolución de esta enfermedad infecciosa en ocho países europeos, a la vez que pretendemos llamar la atención a los dentistas acerca del papel que deben desempeñar en el diagnóstico de la enfennedad y en la derivación a centros de control de infecciones de transmisión sexual

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In 2009, Cygnus X-3 (Cyg X-3) became the first microquasar to be detected in the GeV γ-ray regime, via the satellites Fermi and AGILE. The addition of this new band to the observational toolbox holds promise for building a more detailed understanding of the relativistic jets of this and other systems. We present a rich data set of radio, hard and soft X-ray, and γ-ray observations of Cyg X-3 made during a flaring episode in 2010 May. We detect a ~3 day softening and recovery of the X-ray emission, followed almost immediately by a ~1 Jy radio flare at 15 GHz, followed by a 4.3σ γ-ray flare (E > 100 MeV) ~1.5 days later. The radio sampling is sparse, but we use archival data to argue that it is unlikely the γ-ray flare was followed by any significant unobserved radio flares. In this case, the sequencing of the observed events is difficult to explain in a model in which the γ-ray emission is due to inverse Compton scattering of the companion star's radiation field. Our observations suggest that other mechanisms may also be responsible for γ-ray emission from Cyg X-3.

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A heavy precipitation event swept over Catalonia (NE Spain) on 8 March 2010, with a total amount that ex- ceeded 100mm locally and snowfall of more than 60cm near the coast. Unusual for this region and at this time of the year, this snowfall event affected mainly the coastal region and was accompanied by thunderstorms and strong wind gusts in some areas. Most of the damage was due to"wet snow", a kind of snow that favours accretion on power lines and causes line-breaking and subsequent interruption of the electricity supply. This paper conducts an interdisciplinary analysis of the event to show its great societal impact and the role played by the recently developed social networks (it has been called the first"Snowfall 2.0"), as well to analyse the meteorologi- cal factors associated with the major damage, and to propose an indicator that could summarise them. With this aim, the paper introduces the event and its societal impact and com- pares it with other important snowfalls that have affected the Catalan coast, using the PRESSGAMA database. The sec- ond part of the paper shows the event"s main meteorological features and analyses the near-surface atmospheric variables responsible for the major damage through the application of the SAFRAN (Système d"analyse fournissant des renseigne- ments atmosphériques à la neige) mesoscale analysis, which, together with the proposed"wind, wet-snow index" (WWSI), allows to estimate the severity of the event. This snow storm provides further evidence of our vulnerability to natural haz- ards and highlights the importance of a multidisciplinary ap- proach in analysing societal impact and the meteorological factors responsible for this kind of event.

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Little is known about how genetic and environmental factors contribute to the association between parental negativity and behavior problems from early childhood to adolescence. The current study fitted a cross-lagged model in a sample consisting of 4,075 twin pairs to explore (a) the role of genetic and environmental factors in the relationship between parental negativity and behavior problems from age 4 to age 12, (b) whether parent-driven and child-driven processes independently explain the association, and (c) whether there are sex differences in this relationship. Both phenotypes showed substantial genetic influence at both ages. The concurrent overlap between them was mainly accounted for by genetic factors. Causal pathways representing stability of the phenotypes and parent-driven and child-driven effects significantly and independently account for the association. Significant but slight differences were found between males and females for parent-driven effects. These results were highly similar when general cognitive ability was added as a covariate. In summary, the longitudinal association between parental negativity and behavior problems seems to be bidirectional and mainly accounted for by genetic factors. Furthermore, child-driven effects were mainly genetically mediated, and parent-driven effects were a function of both genetic and shared-environmental factors.

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La asignatura de Cultivos Celulares impartida en la Licenciatura de Biología de la Universidad de Sevilla, proporciona a los alumnos información teórica y práctica en esta materia. El gran avance tecnológico de los cultivos celulares aconseja complementar la información. Para ello hemos realizado una actividad formativa que ha permitido a profesionales procedentes de otras universidades o empresas, proporcionar de forma directa y sin desplazarse, conocimientos sobre las técnicas más innovadoras en cultivos celulares. Se han realizado dos conferencias a distancia mediante el uso de la herramienta Wimba Classroom. Se evaluó el grado de comprensión de las conferencias por parte de los alumnos mediante las herramientas tarea y examen de WebCT, así como la posible repercusión en la nota final. Los resultados obtenidos mostraron un incremento en el número de aprobados y de presentados a examen en el grupo experimental con respecto al control, así como un aumento de la nota media obtenida (5,92 frente a 4,01). Los alumnos evaluaron distintos aspectos de la actividad mediante encuestas a través de la plataforma, en las cuales se obtuvo un grado de valoración de la misma muy positivo. Los resultados indican que el uso de Wimba Classroom es adecuado para el objetivo propuesto.

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Recent reports point out the importance of the complex GK-GKRP in controlling glucose and lipid homeostasis. Several GK mutations affect GKRP binding, resulting in permanent activation of the enzyme. We hypothesize that hepatic overexpression of a mutated form of GK, GKA456V, described in a patient with persistent hyperinsulinemic hypoglycemia of infancy (PHHI) and could provide a model to study the consequences of GK-GKRP deregulation in vivo. GKA456V was overexpressed in the liver of streptozotocin diabetic mice. Metabolite profiling in serum and liver extracts, together with changes in key components of glucose and lipid homeostasis, were analyzed and compared to GK wild-type transfected livers. Cell compartmentalization of the mutant but not the wild-type GK was clearly affected in vivo, demonstrating impaired GKRP regulation. GKA456V overexpression markedly reduced blood glucose in the absence of dyslipidemia, in contrast to wild-type GK-overexpressing mice. Evidence in glucose utilization did not correlate with increased glycogen nor lactate levels in the liver. PEPCK mRNA was not affected, whereas the mRNA for the catalytic subunit of glucose-6-phosphatase was upregulated ~4 folds in the liver of GKA456V-treated animals, suggesting that glucose cycling was stimulated. Our results provide new insights into the complex GK regulatory network and validate liver-specific GK activation as a strategy for diabetes therapy.

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The expansion of an isolated hot spherical nucleus with excitation energy and its caloric curve are studied in a thermodynamic model with the SkM∗ force as the nuclear effective two-body inter-action. The calculated results are shown to compare well with the recent experimental data from energetic nuclear collisions. The fluctuations in temperature and density are also studied. They are seen to build up very rapidly beyond an excitation energy of ∼9 MeV/u. Volume-conserving quadrupole deformation in addition to expansion indicates , however, nuclear disassembly above an excitation energy of ∼4 MeV/u.

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Hydrogenated nanocrystalline silicon thin-films were obtained by catalytic chemical vapour deposition at low substrate temperatures (150°C) and high deposition rates (10 Å/s). These films, with crystalline fractions over 90%, were incorporated as the active layers of bottom-gate thin-film transistors. The initial field-effect mobilities of these devices were over 0.5 cm 2/V s and the threshold voltages lower than 4 V. In this work, we report on the enhanced stability of these devices under prolonged times of gate bias stress compared to amorphous silicon thin-film transistors. Hence, they are promising candidates to be considered in the future for applications such as flat-panel displays.

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The charge ordered La1/3Sr2/3FeO3−δ (LSFO) in bulk and nanocrystalline forms are investigated using ac and dc magnetization, M¨ossbauer, and polarized neutron studies. A complex scenario of short-range charge and magnetic ordering is realized from the polarized neutron studies in nanocrystalline specimen. This short-range ordering does not involve any change in spin state and modification in the charge disproportion between Fe3+ and Fe5+ compared to bulk counterpart as evident in the M¨ossbauer results. The refinement of magnetic diffraction peaks provides magnetic moments of Fe3+ and Fe5+ are about 3.15 μB and 1.57 μB for bulk, and 2.7 μB and 0.53 μB for nanocrystalline specimen, respectively. The destabilization of charge ordering leads to magnetic phase separation, giving rise to the robust exchange bias (EB) effect. Strikingly, EB field at 5 K attains a value as high as 4.4 kOe for average size ∼70 nm, which is zero for the bulk counterpart. A strong frequency dependence of ac susceptibility reveals cluster-glass-like transition around ∼65 K, below which EB appears. Overall results propose that finite-size effect directs the complex glassy magnetic behavior driven by unconventional short-range charge and magnetic ordering, and magnetic phase separation appears in nanocrystalline LSFO.

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During October 23rd and 24th and November 2012 we collected a sample of drosophilids at Font Groga (Barcelona). This site is located on the foothills of the Tibidabo mountain, which is located on the northwest edge of Barcelona and at approximately 400m above sea level. The vegetation is typical for the area, and it is mainly composed of a sparse pine forest (Pinus pinea) with some oaks (Quercus ilex) and Mediterranean brushwood. Flies were netted over 12 baits containing fermenting bananas. A large proportion of D. simulans males was found. The invasive species D. suzukii (Calabria et al. 2010; Cini et al. 2012) was detected in a non-negligible quantity. Taking into account the number of males and females, the estimated Ne for D. suzukii in the Font Groga sample was 33.70. A similar value was obtained for D. subobscura (34.97). Finally, in the study of species diversity the values obtained for H" (Shannon diversity index) and J (Shannon uniformity index) were 0.678 and 0.421, respectively. These estimates are very similar to those obtained in September 2009 in Montpellier by Calabria (2012), who reported H" = 0.679 and J = 0.422, but differ from those reported by the same author in a Font Groga sample of October 2007 (H" = 0.904 and J = 0.505).

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Background Chronic obstructive pulmonary disease (COPD) is a complex condition with pulmonary and extra-pulmonary manifestations. This study describes the heterogeneity of COPD in a large and well characterised and controlled COPD cohort (ECLIPSE). Methods We studied 2164 clinically stable COPD patients, 337 smokers with normal lung function and 245 never smokers. In these individuals, we measured clinical parameters, nutritional status, spirometry, exercise tolerance, and amount of emphysema by computed tomography. Results COPD patients were slightly older than controls and had more pack years of smoking than smokers with normal lung function. Co-morbidities were more prevalent in COPD patients than in controls, and occurred to the same extent irrespective of the GOLD stage. The severity of airflow limitation in COPD patients was poorly related to the degree of breathlessness, health status, presence of co-morbidity, exercise capacity and number of exacerbations reported in the year before the study. The distribution of these variables within each GOLD stage was wide. Even in subjects with severe airflow obstruction, a substantial proportion did not report symptoms, exacerbations or exercise limitation. The amount of emphysema increased with GOLD severity. The prevalence of bronchiectasis was low (4%) but also increased with GOLD stage. Some gender differences were also identified. Conclusions The clinical manifestations of COPD are highly variable and the degree of airflow limitation does not capture the heterogeneity of the disease.

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A new electrochemical method to synthesize mesoporous nanowires of alloys has been developed. Electrochemical deposition in ionic liquid-in-water (IL/W) microemulsion has been successful to grow mesoporous CoPt nanowires in the interior of polycarbonate membranes. The viscosity of the medium was high, but it did not avoid the entrance of the microemulsion in the interior of the membrane"s channels. The structure of the IL/W microemulsions, with droplets of ionic liquid (4 nm average diameter) dispersed in CoPt aqueous solution, defined the structure of the nanowires, with pores of a few nanometers, because CoPt alloy deposited only from the aqueous component of the microemulsion. The electrodeposition in IL/W microemulsion allows obtaining mesoporous structures in which the small pores must correspond to the size of the droplets of the electrolytic aqueous component of the microemulsion. The IL main phase is like a template for the confined electrodeposition. The comparison of the electrocatalytic behaviours towards methanol oxidation of mesoporous and compact CoPt nanowires of the same composition, demonstrated the porosity of the material. For the same material mass, the CoPt mesoporous nanowires present a surface area 16 times greater than compact ones, and comparable to that observed for commercial carbon-supported platinum nanoparticles.

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[cat]Els treballs arqueològics duts a terme al solar localitzat entre la plaça de Pau Vila i els carrers del Dr. Aiguader i de la Marquesa, al peu del baluard del Migdia, han permès descriure l'evolució geoarqueològica d'un tram del front marítim de Barcelona i generar dades fiables de la configuració de la façana litoral. Sota una potent capa de sorres, s'identificà un paquet de llims i argiles orgàniques característiques d'un medi de baixa energia; és a dir, protegit de l'onatge marí probablement per barres sorrenques. Aquesta seqüència presenta una cronologia entre finals del segle IX i ca. 1440, moment en què es realitzaren els primers intents de construcció d'estructures portuàries. En aquest nivell llimoargilós s'han dut a terme analítiques paleoambientals consistents en l'estudi pol·línic, sedimentològic i geoquímic dels sediments que han posat en evidència els canvis ambientals del front marítim barceloní, del paisatge vegetal del pla, com també de les activitats agrícoles i productives urbanes en època medieval i inicis de l'edat moderna. La informació així obtinguda ha estat contrastada amb la informació històrica. [eng]The archaeological work conducted at the site located at the foot of the Baluard del Migdia bastion between Plaça Pau Vila and Carrer Dr. Aiguader and Carrer Marquesa has provided the opportunity to describe the geoarchaeological evolution of a stretch of the seafront of Barcelona and to generate reliable data on the configuration of the coastline. A layer of silt and organic clays typical of a low-energy environment was found below a thick layer of sands. In other words, this packet was protected from the swell of the sea, probably by sandbars. This sequence presents a chronology spanning from the late 9th century BC to around 1440, the time when the first attempts were made to build port structures. This layer of silt and clay has been subjected to palaeoenvironmental analyses consisting of the study of the pollen, sediment and the geochemistry of the sediments. The results of this analysis provide evidence of the environmental changes in the seafront of Barcelona and the landscape in the plain, as well as the urban agricultural and production activities in medieval times and the early modern age. The information obtained has been compared with historical information.

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Objectives: To determine the epidemiology and describe the clinical and radiographic characteristics, the type of treatment, and the possible delayed appearance of new supernumerary teeth in patients with non-syndromic multiple hyperdontia. Patients and Methods: We conducted a small retrospective observational study of 8 patients diagnosed with nonsyndromic multiple hyperdontia. Multiple hyperdontia not associated to complex syndromes was defined as apparently generally healthy patients with one or more supernumerary teeth in two or more areas. Results: The average patient age was 16.23 years; males predominated (3:1). Multiple hyperodontia with a minimum of 2 and a maximum of 9 supernumerary teeth was found (total: 34 mean: 4.25). The most frequent location was the upper jaw (76.47%). Eumorphic teeth were seen at lower premolar level, while the rest were all heteromorphic. There was altered eruption of the contiguous teeth of 4 of the impacted supernumerary teeth all the rest being asymptomatic. Extraction was the treatment in all patients, and in one of them the delayed appearance of 4 supernumerary teeth was detected. Conclusions: Multiple hyperodontia rarely occurs without being associated with complex syndromes. Prophylactic surgical removal of the supernumerary teeth is generally the treatment of choice.

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Objective: The aim of this in vitro experimental study was to perform histological evaluation of the thermal effect produced on soft tissue irradiated with CO2, Er,Cr:YSGG or diode lasers. Study design: Porcine oral mucosa samples were irradiated with Er,Cr:YSGG laser at 1 W with and without water / air spray, at 2 W with and without water / air spray, and at 4 W with water / air spray, with CO2 laser at 1 W, 2 W, 10 W, 20 W continuous mode and 20 W pulsed mode and diode laser at 2W, 5W, and 10W pulsed mode. The thermal effect was evaluated measuring the width of damaged tissue adjacent to the incision, stained positively for hyalinized tissue with Hematoxylin-Eosin and Masson Trichrome stains. Besides, histological changes in the irradiated tissue were described using subjective grading scales. Results: The evaluated lasers developed a wide range of thermal damage with significant differences between groups. The samples with lowest thermal effect were those irradiated with Er,Cr:YSGG laser using water / air spray, followed by CO2 and diode lasers. Conclusions: Emission parameters of each laser system may influence the thermal damage inflicted on the soft tissue, however, the wave length of each laser determines the absorption rate characteristics of every tissue and the thermal effect