41 research outputs found

    Electron Bernstein waves emission in the TJ-II Stellarator

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    Taking advantage of the electron Bernstein waves heating (EBWH) system of the TJ-II stellarator, an electron Bernstein emission (EBE) diagnostic was installed. Its purpose is to investigate the B-X-O radiation properties in the zone where optimum theoretical EBW coupling is predicted. An internal movable mirror shared by both systems allows us to collect the EBE radiation along the same line of sight that is used for EBW heating. The theoretical EBE has been calculated for different orientations of the internal mirror using the TRUBA code as ray tracer. A comparison with experimental data obtained in NBI discharges is carried out. The results provide a valuable information regarding the experimental O-X mode conversion window expected in the EBW heating experiments. Furthermore, the characterization of the radiation polarization shows evidence of the underlying B-X-O conversion process.Comment: 21 pages, 14 figure

    Calculation of the bootstrap current profile for the TJ-II stellarator

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    Calculations of the bootstrap current for the TJ-II stellarator are presented. DKES and NEO-MC codes are employed; the latter has allowed, for the first time, the precise computation of the bootstrap transport coefficient in the long mean free path regime of this device. The low error bars allow a precise convolution of the monoenergetic coefficients, which is confirmed by error analysis. The radial profile of the bootstrap current is presented for the first time for the 100_44_64 configuration of TJ-II for three different collisionality regimes. The bootstrap coefficient is then compared to that of other configurations of TJ-II regularly operated. The results show qualitative agreement with toroidal current measurements; precise comparison with real discharges is ongoing

    Overview of recent TJ-II stellarator results

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    The main results obtained in the TJ-II stellarator in the last two years are reported. The most important topics investigated have been modelling and validation of impurity transport, validation of gyrokinetic simulations, turbulence characterisation, effect of magnetic configuration on transport, fuelling with pellet injection, fast particles and liquid metal plasma facing components. As regards impurity transport research, a number of working lines exploring several recently discovered effects have been developed: the effect of tangential drifts on stellarator neoclassical transport, the impurity flux driven by electric fields tangent to magnetic surfaces and attempts of experimental validation with Doppler reflectometry of the variation of the radial electric field on the flux surface. Concerning gyrokinetic simulations, two validation activities have been performed, the comparison with measurements of zonal flow relaxation in pellet-induced fast transients and the comparison with experimental poloidal variation of fluctuations amplitude. The impact of radial electric fields on turbulence spreading in the edge and scrape-off layer has been also experimentally characterized using a 2D Langmuir probe array. Another remarkable piece of work has been the investigation of the radial propagation of small temperature perturbations using transfer entropy. Research on the physics and modelling of plasma core fuelling with pellet and tracer-encapsulated solid-pellet injection has produced also relevant results. Neutral beam injection driven Alfvénic activity and its possible control by electron cyclotron current drive has been examined as well in TJ-II. Finally, recent results on alternative plasma facing components based on liquid metals are also presented. ISSN:0029-5515 ISSN:1741-432

    Molecular basis of caspase-1 polymerization and its inhibition by a new capping mechanism

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    Inflammasomes are cytosolic caspase-1-activation complexes that sense intrinsic and extrinsic danger signals, and trigger inflammatory responses and pyroptotic cell death. Homotypic interactions among Pyrin domains and caspase recruitment domains (CARDs) in inflammasome-complex components mediate oligomerization into filamentous assemblies. Several cytosolic proteins consisting of only interaction domains exert inhibitory effects on inflammasome assembly. In this study, we determined the structure of the human caspase-1 CARD domain (caspase-1[superscript CARD]) filament by cryo-electron microscopy and investigated the biophysical properties of two caspase-1-like CARD-only proteins: human inhibitor of CARD (INCA or CARD17) and ICEBERG (CARD18). Our results reveal that INCA caps caspase-1 filaments, thereby exerting potent inhibition with low-nanomolar K[subscript i] on caspase-1[superscript CARD] polymerization in vitro and inflammasome activation in cells. Whereas caspase-1[superscript CARD] uses six complementary surfaces of three types for filament assembly, INCA is defective in two of the six interfaces and thus terminates the caspase-1 filament

    Integrated monitoring of mola mola behaviour in space and time

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    Over the last decade, ocean sunfish movements have been monitored worldwide using various satellite tracking methods. This study reports the near-real time monitoring of finescale (< 10 m) behaviour of sunfish. The study was conducted in southern Portugal in May 2014 and involved satellite tags and underwater and surface robotic vehicles to measure both the movements and the contextual environment of the fish. A total of four individuals were tracked using custom-made GPS satellite tags providing geolocation estimates of fine-scale resolution. These accurate positions further informed sunfish areas of restricted search (ARS), which were directly correlated to steep thermal frontal zones. Simultaneously, and for two different occasions, an Autonomous Underwater Vehicle (AUV) videorecorded the path of the tracked fish and detected buoyant particles in the water column. Importantly, the densities of these particles were also directly correlated to steep thermal gradients. Thus, both sunfish foraging behaviour (ARS) and possibly prey densities, were found to be influenced by analogous environmental conditions. In addition, the dynamic structure of the water transited by the tracked individuals was described by a Lagrangian modelling approach. The model informed the distribution of zooplankton in the region, both horizontally and in the water column, and the resultant simulated densities positively correlated with sunfish ARS behaviour estimator (r(s) = 0.184, p < 0.001). The model also revealed that tracked fish opportunistically displace with respect to subsurface current flow. Thus, we show how physical forcing and current structure provide a rationale for a predator's finescale behaviour observed over a two weeks in May 2014

    Efficient discovery of anti-inflammatory small-molecule combinations using evolutionary computing

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    The control of biochemical fluxes is distributed, and to perturb complex intracellular networks effectively it is often necessary to modulate several steps simultaneously. However, the number of possible permutations leads to a combinatorial explosion in the number of experiments that would have to be performed in a complete analysis. We used a multiobjective evolutionary algorithm to optimize reagent combinations from a dynamic chemical library of 33 compounds with established or predicted targets in the regulatory network controlling IL-1β expression. The evolutionary algorithm converged on excellent solutions within 11 generations, during which we studied just 550 combinations out of the potential search space of ~9 billion. The top five reagents with the greatest contribution to combinatorial effects throughout the evolutionary algorithm were then optimized pairwise. A p38 MAPK inhibitor together with either an inhibitor of IκB kinase or a chelator of poorly liganded iron yielded synergistic inhibition of macrophage IL-1β expression. Evolutionary searches provide a powerful and general approach to the discovery of new combinations of pharmacological agents with therapeutic indices potentially greater than those of single drugs

    Comparación de las lesiones no mortales por accidente de trabajo por Comunidades Autónomas en España (1994-2004) Comparison of non-fatal occupational injuries by autonomous communities in Spain (1994-2004)

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    Objetivos: Dadas las diferencias observadas en estudios previos de la incidencia de lesiones por accidente de trabajo (LAT) por Comunidades Autónomas (CC.AA.), en este estudio hemos evaluado la hipótesis de homogeneidad de la incidencia de las LAT para tipos específicos de accidentes y en determinadas actividades, entre 1994 y 2004. Métodos: Las LAT analizadas fueron no mortales con baja, de tipo mecánico y sobreesfuerzo, ocurridas en jornada en centro para empresas manufactureras y de la construcción. Se calculó el riesgo relativo ajustado por sexo, edad y tipo de contrato en cada una de las CC.AA. mediante la razón de LAT estandarizada, tomando como referencia las tasas de España, y estratificando según duración de la baja (menos de 16 días y más de 15 días). Resultados: El riesgo relativo ajustado de LAT según los diferentes tipos de accidentes analizados presenta una distribución heterogénea entre CC.AA. Murcia, Navarra, Baleares y País Vasco se encuentran generalmente entre las comunidades con riesgos más elevados, mientras que Castilla-León y Extremadura son las que tienen principalmente menores riesgos de sufrir una LAT. Conclusiones: La heterogeneidad en la incidencia de LAT entre CC.AA. persiste después de seleccionar una serie de formas de accidente específicas y ajustar por sexo, edad y tipo de contrato. Por ello sugerimos que, además de seguir analizando las condiciones de trabajo como explicación de esta heterogeneidad, se tengan en cuenta otras variables socioeconómicas al comparar las incidencias de LAT entre CC.AA.Objectives: Given the differences observed in previous studies with respect to occupational injury rates in Spain's autonomous communities, this study tested the homogeneity hypothesis of occupational injury for specific accident types and economic activity between 1994 and 2004. Methods: We analyzed non-fatal injuries of a mechanical nature or those due to overexertion taking place in manufacturing or construction companies during the workday and requiring sick leave. The relative risk was adjusted for sex, age and contract type in each autonomous community using standardized injury causes for occupational injury, employing Spanish rates as a reference and stratifying by duration of leave (less than 16 days and more than 15 days). Results: For the different types of accidents analyzed, the adjusted relative risk of occupational injury was heterogeneously distributed across the autonomous communities. Murcia, Navarre, the Balearic Islands and the Basque Country were generally found to be amongst the communities with the most elevated risks, while Castilla-León and Extremadura were those with the lowest risks of occupational injury. Conclusions: The heterogeneity of occupational injury rates across autonomous communities persisted after selecting a series of specific accident types and adjusting for sex, age and contract type. Therefore, in addition to continued analysis of work conditions to explain this variation, other socioeconomic factors should be taken into account when comparing occupational injury rates among autonomous communities

    Zootechnical archives. Editorial report 2010.

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    The editorial process of Archivos de Zootecnia during 2010 is reported below. A total of 384 manuscripts were received from 33 countries, mainly from Brazil (66.9%). Consequently, the language most frequently used in the manuscripts was Portuguese, followed by Spanish and English. The mean time between submission and publication of a manuscript was 836.3 days. The rejection rate was 50.8%. In 2010, 49 articles, 21 short notes and 10 reviews (total 83) were published by authors coming from 15 countries.Se analiza el proceso editorial de Archivos de Zootecnia durante 2010. Se recibieron 384 manuscritos procedentes de 33 países, principalmente de Brasil (66,9%). Consecuentemente, el lenguaje más frecuentemente usado fue el portugués, seguido del español y el inglés. El tiempo medio entre recepción y publicación de un manuscrito fue elevado ( 836.3 dias). La tasa de rechazo fue del 50,8%. En 2010 fueron publicados 49 artículos, 21 notas breves y 10 revisiones (83 trabajos en total) cuyos autores pertenecían a 15 países diferentes

    Presencia de alteraciones histopatológicas en vellosidades placentarias normales en Maracay (Venezuela) The presence of hystopathological alterations in normal placental villi in Maracay, Venezuela

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    Objetivo: determinar la proporción de las alteraciones histopatológicas en las vellosidades y en el espacio intervelloso obtenida de cuatro placentas normales del último trimestre del embarazo. Metodología: por medio de la microscopía de luz y la tinción de hematoxilina y eosina (H&E) se identificaron, en 25 láminas de 5 regiones de la placenta, 6 variables cuantitativas (p.ej. inmadurez vellosa, nódulos sincitiales, cambios fibrinoides, edema velloso, fibrosis estromal y calcificación) y 9 variables cualitativas (p.ej. depósitos de fibrina, trombosis intervellosa, infartos, trombosis vascular, cambios en la pared del vaso, calcificación intraluminal, congestión vascular,inflamaciónyhemorragia).Los resultados de las variables cuantitativas se analizaron utilizando el Análisis de Varianza (ANAVAR) de 2 vías con submuestreo y el test de Tukey. En contraste, para las variables cualitativas se aplicó la prueba de Kruskal Wallis y se estimó el porcentaje de positividad según las regiones. Dichos análisis se realizaron por medio del software Statistix® 8.0 y SAS® 9.0 para Windows®. Resultados: no se presentaron diferencias significativas (pObjective: determining the percentage of histopathological changes in chorionic villi and intervillous space in four placentas obtained from normal women's pregnancies at term. Methodology: six quantitative variables (i.e. immaturity, syncytial knots, fibrinoid change, oedema, fibrosis and calcification) and nine qualitative variables (i.e. fibrin deposition, intervillous fibrin, infarction, thrombosis, changes in vessel walls, intraluminal calcification, vascular congestion, inflammation and haemorrhage) were indentified on 25 slides covering 5 placental regions using light microscopy and H&E staining. Quantitative variable results were analysed using two-way variance analysis with sub-sampling and Tukey&rsquo;s test; qualitative variables (the percentage of positive regions) were analysed by Kruskal-Wallis test. The software used was Statistix® 8.0 and SAS® 9.0 for Windows®. Results: there were significant differences (p<0.05) between placenta (but not between regions) regarding syncytial knots, fibrinoid change, oedema, fibrosis and calcification. Vascular thrombosis, damage to vessel walls, vascular congestion, intraluminal calcification, inflammation and/or haemorrhage were not observed. Conclusion: the population of villi analysed was homogeneous in each placenta but not amongst them, thereby indicating variability which could be etiologically explained by genetic and environmental factors whose interaction may have resulted in the individual differences observed for each placenta
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