100 resultados para Louro-pardo


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Background: Nolz1 is a zinc finger transcription factor whose expression is enriched in the lateral ganglionic eminence (LGE), although its function is still unknown. Results: Here we analyze the role of Nolz1 during LGE development. We show that Nolz1 expression is high in proliferating neural progenitor cells (NPCs) of the LGE subventricular zone. In addition, low levels of Nolz1 are detected in the mantle zone, as well as in the adult striatum. Similarly, Nolz1 is highly expressed in proliferating LGE-derived NPC cultures, but its levels rapidly decrease upon cell differentiation, pointing to a role of Nolz1 in the control of NPC proliferation and/or differentiation. In agreement with this hypothesis, we find that Nolz1 over-expression promotes cell cycle exit of NPCs in neurosphere cultures and negatively regulates proliferation in telencephalic organotypic cultures. Within LGE primary cultures, Nolz1 over-expression promotes the acquisition of a neuronal phenotype, since it increases the number of β-III tubulin (Tuj1)- and microtubule-associated protein (MAP)2-positive neurons, and inhibits astrocyte generation and/or differentiation. Retinoic acid (RA) is one of the most important morphogens involved in striatal neurogenesis, and regulates Nolz1 expression in different systems. Here we show that Nolz1 also responds to this morphogen in E12.5 LGE-derived cell cultures. However, Nolz1 expression is not regulated by RA in E14.5 LGE-derived cell cultures, nor is it affected during LGE development in mouse models that present decreased RA levels. Interestingly, we find that Gsx2, which is necessary for normal RA signaling during LGE development, is also required for Nolz1 expression, which is lost in Gsx2 knockout mice. These findings suggest that Nolz1 might act downstream of Gsx2 to regulate RA-induced neurogenesis. Keeping with this hypothesis, we show that Nolz1 induces the selective expression of the RA receptor (RAR)β without altering RARα or RARγ. In addition, Nozl1 over-expression increases RA signaling since it stimulates the RA response element. This RA signaling is essential for Nolz1-induced neurogenesis, which is impaired in a RA-free environment or in the presence of a RAR inverse agonist. It has been proposed that Drosophila Gsx2 and Nolz1 homologues could cooperate with the transcriptional co-repressors Groucho-TLE to regulate cell proliferation. In agreement with this view, we show that Nolz1 could act in collaboration with TLE-4, as they are expressed at the same time in NPC cultures and during mouse development. Conclusions: Nolz1 promotes RA signaling in the LGE, contributing to the striatal neurogenesis during development.

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Background: Nolz1 is a zinc finger transcription factor whose expression is enriched in the lateral ganglionic eminence (LGE), although its function is still unknown. Results: Here we analyze the role of Nolz1 during LGE development. We show that Nolz1 expression is high in proliferating neural progenitor cells (NPCs) of the LGE subventricular zone. In addition, low levels of Nolz1 are detected in the mantle zone, as well as in the adult striatum. Similarly, Nolz1 is highly expressed in proliferating LGE-derived NPC cultures, but its levels rapidly decrease upon cell differentiation, pointing to a role of Nolz1 in the control of NPC proliferation and/or differentiation. In agreement with this hypothesis, we find that Nolz1 over-expression promotes cell cycle exit of NPCs in neurosphere cultures and negatively regulates proliferation in telencephalic organotypic cultures. Within LGE primary cultures, Nolz1 over-expression promotes the acquisition of a neuronal phenotype, since it increases the number of β-III tubulin (Tuj1)- and microtubule-associated protein (MAP)2-positive neurons, and inhibits astrocyte generation and/or differentiation. Retinoic acid (RA) is one of the most important morphogens involved in striatal neurogenesis, and regulates Nolz1 expression in different systems. Here we show that Nolz1 also responds to this morphogen in E12.5 LGE-derived cell cultures. However, Nolz1 expression is not regulated by RA in E14.5 LGE-derived cell cultures, nor is it affected during LGE development in mouse models that present decreased RA levels. Interestingly, we find that Gsx2, which is necessary for normal RA signaling during LGE development, is also required for Nolz1 expression, which is lost in Gsx2 knockout mice. These findings suggest that Nolz1 might act downstream of Gsx2 to regulate RA-induced neurogenesis. Keeping with this hypothesis, we show that Nolz1 induces the selective expression of the RA receptor (RAR)β without altering RARα or RARγ. In addition, Nozl1 over-expression increases RA signaling since it stimulates the RA response element. This RA signaling is essential for Nolz1-induced neurogenesis, which is impaired in a RA-free environment or in the presence of a RAR inverse agonist. It has been proposed that Drosophila Gsx2 and Nolz1 homologues could cooperate with the transcriptional co-repressors Groucho-TLE to regulate cell proliferation. In agreement with this view, we show that Nolz1 could act in collaboration with TLE-4, as they are expressed at the same time in NPC cultures and during mouse development. Conclusions: Nolz1 promotes RA signaling in the LGE, contributing to the striatal neurogenesis during development.

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Se ha aplicado el QBR (índice de calidad del bosque de ribera) a 157 estaciones de muestreo localizadas en ríos pertenecientes a 12 cuencas diferentes del ámbito mediterráneo español. Los resultados indican que más del 34 % de las estaciones muestran valores de calidad buenos y muy buenos (QBR > 75), mientras que el 45 % presenta valores de mala y pésima calidad (QBR < 50). Según una tipología previa establecida para clasificar las estaciones de muestreo, los valores de mayor calidad de QBR se dan en estaciones de cabecera de cuencas calcáreas y en las zonas de karst. Los tipos denominados temporales y ramblas presentan los valores más bajos de calidad, o no tiene representantes de máxima calidad. La ausencia o escasez de bosques de riberas de máxima calidad en las cuencas del sur peninsular puede explicarse por el gradiente de aridez que se establece desde el norte hacia el sur. Además existe un evidente deterioro de las riberas desde las cabeceras a las desembocaduras de los ríos, de manera que ambos factores influyen en el estado actual de las riberas de los ríos mediterráneos ibéricos. Finalmente se discute la utilidad y limitaciones del QBR en ríos sometidos a situaciones de estrés hídrico o ambiental.

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ABSTRACT Proposal for an evaluation protocol of the ecological quality of Andean rivers (CERA) and its use in two basins in Ecuador and Peru A Rapid Protocol is presented for Evaluation of the Ecological Status of Andean Rivers (CERA) localized over 2000 m.a.s.l. from the Northern Andes (Venezuela) through the Altiplano in the Central Andes (Bolivia). This protocol was used in 45 sampling sites in the Guayllabamba River Basin in Ecuador and in 42 sampling sites in the Ca nete River Basin in Peru. Previously, and in order to test if the sampling stations may or not be considered reference stations, we constructed a method that assesses 24 basin attributes, hydrology, reach and riverbed and that uctuates from 24 to 120 points; sites with values higher than 100 were considered as potential reference sites. Besides the benthic macroinvertebrats" evaluation, the river habitat and riparian vegetation were also evaluated through of the application of the indices ABI (R´ os et al., submitted), IHF (Pardo et al., 2002) and QBR-And, respectively. The convenience of the initial allocation of the reference sites was evaluated as well. These indices have been properly adapted to the conditions and characteristics of the high Andes rivers. The results obtained for both basins were compared and discussed. Through the use of the CERA protocol, the particular perturbation gradients and the natural variability of the reference sites in both countries were recognized. RESUMEN Propuesta de un protocolo de evaluación de la calidad ecológica de ríos andinos (CERA) y su aplicaci´on a dos cuencas en Ecuador y Perú Se presenta un protocolo rápido de evaluación de la Calidad Ecológica de Ríos Andinos (CERA), situados sobre los 2000 m.s.n.m, desde los Andes del Norte (Venezuela) hasta el Altiplano de los Andes Centrales (Bolivia). Este protocolo ha sido aplicado en 45 estaciones de muestreo en la cuenca del río Guayllabamba en Ecuador y en 42 estaciones de muestreo en la cuenca del río Cañete en Perú. Previamente, para probar si las estaciones de muestreo pueden o no ser estaciones de referencia construimos un método que valora 24 atributos de cuenca, hidrología, tramo y lecho y que fluctúa de 24 a 120 puntos; valores superiores a 100 fueron considerados como sitios potencialmente de referencia. Además del estudio de los macroinvertebrados bentónicos, se evaluó el hábitat fluvial y la comunidad vegetal de ribera a través de la aplicación de los índices ABI (Ríos et al., sometido), IHF (Pardo et al., 2002) y QBR-And respectivamente; así como la conveniencia de la asignación inicial de las estaciones de referencia. Estos índices han sido adecuadamente adaptados a las condiciones y características propias de los ríos altoandinos. Los resultados obtenidos fueron comparados y discutidos entre ambas cuencas. Mediante la aplicación del protocolo CERA se han reconocido los respectivos gradientes de perturbación y la variabilidad natural de las estaciones de referencia en ambos países.

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El diseño de un modelo de aplicación web institucional universitaria con categorías, propiedades y fases evolutivas específicas ejerció como unidad de medida para la observación de 64 sitios web de facultades de comunicación de Iberoamérica. Finalmente, 10 sitios han sido escogidos para su análisis detallado, bajo las pautas del modelo diseñado. Los resultados señalan que menos de una decena de sitios web están en condiciones de considerarse productos eficientes de comunicación y gestión.

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Este artículo es un recorrido a través del proceso de diseño de Diálogos de la Comunicación versión en línea, un procedimiento que ha incluido diferentes fases: desde la fijación de objetivos hasta la realización de un prototipo, pasando por el estudio de buenas prácticas (benchmarking), el desarrollo de la arquitectura de la información y la realización del diseño de la interfaz. El trabajo también aporta una reflexión sobre la situación de las revistas científicas en los entornos de comunicación colaborativa en línea.

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Reseña del seminario organizado desde los Estudios de Derecho y Ciencia Política de la UOC por el Dr. Marc Tarrés. La actividad se realizó bajo el auspicio de la Escuela de Administración Pública de Cataluña y tuvo lugar en el Salón de Grados de la Universidad de Barcelona (UB), los días 19 y 20 de noviembre del 2008. El seminario contó con la presencia de reconocidos especialistas procedentes de los ámbitos académico y judicial, quienes expusieron ante una nutrida concurrencia el papel de los poderes públicos ante situaciones de riesgo. Los ponentes fueron el Dr. José Esteve Pardo, catedrático de Derecho Administrativo de la UB, el Dr. Juan Antonio Carrillo Donaire, profesor titular de Derecho administrativo de la Universidad de Sevilla, el Dr. Gabriel Doménech, profesor de Derecho administrativo del CEU - San Pablo de Valencia, el Ilmo. Sr. Manuel Táboas Bentanachs, magistrado de la Sala Contenciosa Administrativa del TSJ de Cataluña, y el Dr. Francesc Rodríguez Pontón, profesor titular de Derecho administrativo de la UB. En el transcurso de dos jornadas se abordaron especialmente los casos relacionados con la seguridad de los alimentos, la biotecnología y la protección medioambiental. En todos esos sectores se analizó la operatividad del principio de precaución, la responsabilidad de las administraciones públicas, el papel del procedimiento administrativo y la autorregulación.

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Les restes esquelètiques analitzades corresponen tant al nivell neolític (n=26) com a l"època del bronze (n=2), encara que aquí es presenten tan sols els resultats de la població neolítica (taula 1). En tots els casos les sepultures són individuals, amb l"única excepció de la sepultura 20, on s"han recuperat les restes corresponents a un individu femení adult (CSP201) i un fetus (CSP202) (taula 1). Per tal de caracteritzar biomètricament la població s"ha emprat la metodologia proposada per Martin i Saller (1959), Brothwell (1981) i Bass (1971). La determinació del sexe s"ha realitzat a través dels caràcters sexuals secundaris del crani i de la pelvis, i se"n pot trobar una descripció més detallada a Estebaranz et alii (2007). En el cas específic de les paleopatologies es van seguir les recomanacions de Campillo (Campillo, 1977).

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Background: Differences in the distribution of genotypes between individuals of the same ethnicity are an important confounder factor commonly undervalued in typical association studies conducted in radiogenomics. Objective: To evaluate the genotypic distribution of SNPs in a wide set of Spanish prostate cancer patients for determine the homogeneity of the population and to disclose potential bias. Design, Setting, and Participants: A total of 601 prostate cancer patients from Andalusia, Basque Country, Canary and Catalonia were genotyped for 10 SNPs located in 6 different genes associated to DNA repair: XRCC1 (rs25487, rs25489, rs1799782), ERCC2 (rs13181), ERCC1 (rs11615), LIG4 (rs1805388, rs1805386), ATM (rs17503908, rs1800057) and P53 (rs1042522). The SNP genotyping was made in a Biotrove OpenArrayH NT Cycler. Outcome Measurements and Statistical Analysis: Comparisons of genotypic and allelic frequencies among populations, as well as haplotype analyses were determined using the web-based environment SNPator. Principal component analysis was made using the SnpMatrix and XSnpMatrix classes and methods implemented as an R package. Non-supervised hierarchical cluster of SNP was made using MultiExperiment Viewer. Results and Limitations: We observed that genotype distribution of 4 out 10 SNPs was statistically different among the studied populations, showing the greatest differences between Andalusia and Catalonia. These observations were confirmed in cluster analysis, principal component analysis and in the differential distribution of haplotypes among the populations. Because tumor characteristics have not been taken into account, it is possible that some polymorphisms may influence tumor characteristics in the same way that it may pose a risk factor for other disease characteristics. Conclusion: Differences in distribution of genotypes within different populations of the same ethnicity could be an important confounding factor responsible for the lack of validation of SNPs associated with radiation-induced toxicity, especially when extensive meta-analysis with subjects from different countries are carried out.

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Donde se localiza lo risible musical en las relaciones que el compositor establece con su propio material de trabajo, en la gravedad o en el peso relativo del efecto sonoro, con el que se logran divertimentos y humoradas para el oído del que escucha y placeres insospechados para el cuerpo atento y sorprendido por el recorrido musical; y donde finalmente, tras analizar diversos ejemplos, se propone una diferencia entre la mecánica de la risa musical anterior al siglo XX y aquella que es producto de la levedad consustancial a la música contemporánea.

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Inclinado hacia delante John Cage extiende su mano para tocar el agua y, con ese gesto, promueve una partitura inédita. En el gesto de Cage se condensa el rechazo a un papel pautado en el que durante largo tiempo los sonidos musicales encontraron un espacio en el que establecer sus relaciones

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Este proyecto pretende implementar una solución de domótica reutilizando equipos de bajo coste disponibles en una vivienda que son gestionados de forma independiente y carecen de protocolos de comunicaciones estandarizados para su interconexión con otros entornos.

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The genetic impact associated to the Neolithic spread in Europe has been widely debated over the last 20 years. Within this context, ancient DNA studies have provided a more reliable picture by directly analyzing the protagonist populations at different regions in Europe. However, the lack of available data from the original Near Eastern farmers has limited the achieved conclusions, preventing the formulation of continental models of Neolithic expansion. Here we address this issue by presenting mitochondrial DNA data of the original Near-Eastern Neolithic communities with the aim of providing the adequate background for the interpretation of Neolithic genetic data from European samples. Sixty-three skeletons from the Pre Pottery Neolithic B (PPNB) sites of Tell Halula, Tell Ramad and Dja'de El Mughara dating between 8,700-6,600 cal. B.C. were analyzed, and 15 validated mitochondrial DNA profiles were recovered. In order to estimate the demographic contribution of the first farmers to both Central European and Western Mediterranean Neolithic cultures, haplotype and haplogroup diversities in the PPNB sample were compared using phylogeographic and population genetic analyses to available ancient DNA data from human remains belonging to the Linearbandkeramik-Alföldi Vonaldiszes Kerámia and Cardial/Epicardial cultures. We also searched for possible signatures of the original Neolithic expansion over the modern Near Eastern and South European genetic pools, and tried to infer possible routes of expansion by comparing the obtained results to a database of 60 modern populations from both regions. Comparisons performed among the 3 ancient datasets allowed us to identify K and N-derived mitochondrial DNA haplogroups as potential markers of the Neolithic expansion, whose genetic signature would have reached both the Iberian coasts and the Central European plain. Moreover, the observed genetic affinities between the PPNB samples and the modern populations of Cyprus and Crete seem to suggest that the Neolithic was first introduced into Europe through pioneer seafaring colonization.

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Quin hauria de ser el paper de les pràctiques artístiques i la cultura contemporània a la societat? I les institucions artístiques, quin rol haurien d’assolir? Aquest treball final de màster és una indagació entorn els fets més significatius al llarg de la història del món occidental pel que fa a la cultura que s’ha desenvolupat al marge dels poders. Una anàlisi de les relacions que s’estableixen entre aquests diversos àmbits, on es planteja un projecte que compleix les característiques de ser un laboratori per a les pràctiques artístiques contemporànies i la seva recerca. Partint, a més a més, de la base teòrica de la historia cultural que ens porta fins on som ara i com a conformadora de les identitats

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Global warming mitigation has recently become a priority worldwide. A large body of literature dealing with energy related problems has focused on reducing greenhouse gases emissions at an engineering scale. In contrast, the minimization of climate change at a wider macroeconomic level has so far received much less attention. We investigate here the issue of how to mitigate global warming by performing changes in an economy. To this end, we make use of a systematic tool that combines three methods: linear programming, environmentally extended input output models, and life cycle assessment principles. The problem of identifying key economic sectors that contribute significantly to global warming is posed in mathematical terms as a bi criteria linear program that seeks to optimize simultaneously the total economic output and the total life cycle CO2 emissions. We have applied this approach to the European Union economy, finding that significant reductions in global warming potential can be attained by regulating specific economic sectors. Our tool is intended to aid policymakers in the design of more effective public policies for achieving the environmental and economic targets sought.