4,402 research outputs found

    Dust properties in NGC 6611

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    An investigation on dust properties in the NW portion of NGC 6611 has been conducted polarimetrically to test the existence of abnormal extinction in that section of the open cluster in an independent way. As previously suggested for the η Carinae nebula by Tapia et al. (1988b) and subsequently confirmed by Marraco et al. (1993), the canonical relation between EV −K/EB−V and λmax (the wavelength of maximun interstellar polarization) is not valid for stars belonging to dusty H ii regions, as is the case for the observed portion of M 16. This may arise mainly from the presence of silicate grains of a slightly larger size than the standard ISM and also from a considerable increase in mean graphite grain size, according to previous results from Chini & Wargau (1990). About 50% of the observed stars in NGC 6611 present indications of intrinsic polarization in their measurements; a similar percentage was found in IC 2944 (Vega et al. 1994), another young open cluster in close relation with an H ii region.Fil: Orsatti, Ana Maria. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; ArgentinaFil: Vega, Ema Irene. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Marraco, Hugo Gustavo. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; Argentin

    Pismis 20: one or two clusters?

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    We present UBVRI polarimetric observations of stars in the direction of the open cluster Pismis 20 and WR 67. It is found that the observed members segregate polarimetrically into two groups, with different associated mean Pmax (4.31 and 6.08% respectively). Although in the literature these stars are considered as members of the same cluster, the polarized light from these groups clearly differs. There are two possible explanations: very efficient polarizing dust particles exists between certain members of the cluster; or else Pismis 20 is composed of different groupings superimposed along the line of sight. WR 67 belongs to the group more affected by the dust.Fil: Orsatti, Ana Maria. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica la Plata; ArgentinaFil: Vega, Ema Irene. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Marraco, Hugo Gustavo. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica la Plata; Argentin

    Tenerife tiene seguro de sol (y de luna) : representaciones del profesorado de Primaria acerca del día y la noche

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    This study is adressed to report which the ideas about «day» and «night» are from a sample of Primary School Teachers in the Island of Tenerife. A frequent association of the Moon with the night is persistently shown by a third part of teachers. As a consequence, they consider the Moon to be static, and therefore are not able to correctly explain the day and night cycle. Four wrong representations are identified: rotation, revolution, appearance-disappearance and occultation-eclipse. In the light of these results, the author points out the need for revising textbooks contents and images and giving a new direction to teacher's education. Thus, scientific and didactics education has to take into account that it is actually inside the classrooms where pupils learn many of their alternative frameworks transmitted by their own teachers

    Alfredo Mario MORELLI (ed.), Lepos e mores: una giornata su Catullo. Atti del convegno internazionale, Cassino, 27 maggio 2010, Cassino, Edizioni Università di Cassino, 2012 (Collana di studi umanistici, 2.), 286 pp. ISBN 9788883170652.

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    Reseña de Alfredo Mario Morelli (ed.), Lepos e mores: una giornata su Catullo. Atti del convegno internazionale, Cassino, 27 maggio 2010, Cassino, Edizioni Università di Cassino, 2012 (Collana di studi umanistici, 2.), 286 pp. ISBN 9788883170652

    El "Libro del Passer" de Catulo : notas de lectura

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    En estas páginas se discuten algunos pasajes de la poesía de Catulo: los versos 2.6-10 (y en alguna medida los poemas 2 y 3), 4.25- 27, 10.6-8, 11.1, la palabra arca en los poemas 23, 24 y 25; y 42.24.______________________________________ These pages discuss some aspects of Catullus' poetry: 2.6-10 (and to some extent cc. 2 and 3), 4.25-27, 10.6-8, 11.1, the word arca in cc. 23, 24 and 25; and 42.24

    Development and validation of the Scale of Motives for Using Social Networking Sites (SMU-SNS) for adolescents and youths

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    Over the past decade, the Uses and Gratifications theory has driven research on the motives behind social media use. The three most commonly explored motives have been: maintaining relationships, seeking information, and entertainment. The aim of this study was to develop and validate the Scale of Motives for Using Social Networking Sites (SMU-SNS), a measure to assess a wider range of motives for using Social Networking Sites than have previously been researched. A multi-method design with different samples of high-school and university students was used. First, to develop the pool of items, a literature review and a focus group study (n = 48, age range = 16–21) was conducted. Second, to reduce and refine the pool of items a pilot study (n = 168, age range = 14–24) was performed. Third, a validation study (n = 1102, age range = 13–25) was conducted to assess the validity and reliability of the SMU-SNS. Cross-validation using EFA and CFA resulted in a final version comprising 27 items distributed in nine factors (Dating, New Friendships, Academic Purposes, Social Connectedness, Following and Monitoring Others, Entertainment, seeking Social Recognition, Self-expression, and seeking Information). Internal consistency was excellent and evidence of measurement invariance across gender and age was largely achieved. The SMU-SNS scores significantly correlated with other relevant variables, including age, gender, certain personality traits, social support, loneliness, and life satisfaction. Overall, findings supported the SMU-SNS as a valid and reliable measure to assess youth’s motives for using Social Networking Sites. Psychometric and general implications are discussed.Ministerio de Economía y CompetitividadMinisterio de Educación y Formación Profesiona

    La controversia de las acciones constitucionales para garantizar derecho al medio ambiente sano en la zona del Cerrejón

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    Artículo de investigaciónEn síntesis dentro del trabajo se ha desarrollo la explotación y exploración del carbón en la zona del Cerrejón ubicado en el departamento de la Guajira, desde sus inicios hasta el pronunciamiento que tuvo la corte en su sentencia T-256/15, siendo la Tutela el mecanismo adecuado porque no solo se esta vulnerando el derecho al medio ambiente sano sino que involucra derechos fundamentales como lo son el derecho al agua, a la vida digna y a la salud.36 p.RESUMEN ABSTRACT SUMARIO INTRODUCCIÓN 1. EXPLOTACIÒN MINERA DE CARBÒN EN COLOMBIA 2. EL DERECHO AL MEDIO AMBIENTE SANO EN COLOMBIA 3. COMUNIDADES DE LA GUAJIRA EN DEFENSA DEL MEDIO AMBIENTE 4. ACCIONES CONSTITUCIONALES PARA DEFENSA DEL MEDIO AMBIENTE SANO CONCLUSIONES BIBLIOGRAFÌAPregradoAbogad

    Optimization of ERK signalling by transphosphorylation across different scaffold protein species: implication in cancer therapeutics

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    RESUMEN: La ruta de señalización Ras/ERK está claramente relacionada con el desarrollo y progresión de varias enfermedades. Alrededor del 40% de cánceres humanos portan mutaciones en alguno de los constituyentes de esta cascada. Uno de los mecanismos de regulación son las proteínas scaffold, que modulan la intensidad, amplitud y duración de las señales de ERK. Por esta razón algunos scaffolds tienen potencial como diana antitumoral. A tenor de nuevas evidencias que desvelan la interacción entre diferentes especies de proteínas scaffold, hemos propuesto la hipótesis de que las proteínas scaffold interaccionan entre sí para regular el flujo de las señales de ERK de manera coordinada. Esto podría ser una posible explicación de la ineficacia de un novedoso inhibidor de KSR. De hecho, hemos demostrado que KSR1 e IQGAP1 deficientes para la unión de MEK son capaces de incorporar ERK fosforilado. En este respecto, descubrimos que KSR1 e IQGAP1 pueden interaccionar directamente entre sí, permitiendo la “transfosforilación” de ERK unido a la proteína mutante deficiente para unir MEK. Así, asociaciones entre diferentes proteínas scaffold añadirían un grado más a la regulación de una vía de señalización, ya altamente regulada, lo que puede ofrecernos nuevos medios para manipular las señales de ERK, incluso con fines terapéuticos.ABSTRACT: The Ras/ERK pathway is noticeably linked to the development and progression of human malignancies. About 40% of human cancers harbor activating mutations in constituents of this pathway. One of the regulatory mechanisms is carried out by scaffold proteins, that modulate the intensity, amplitude and duration of ERK signals. For this reason, some scaffolds harbor a potential as antitumoral targets. In light of recent evidence unveiling direct interactions among different scaffold proteins species, we have considered the hypothesis that scaffold proteins must somehow interact with each other in order to regulate the flow of signals through the Ras/ERK pathway in a coordinated manner. This could be a possible explanation for the inefficacy of a novel small molecule KSR inhibitor. Indeed, we have shown that KSR1 and IQGAP1 mutants defective for binding MEK, can still associate to phosphorylated ERK. In this respect, we have found that KSR1 and IQGAP1 can directly interact among themselves, and in so doing they can “transphosphorylate” each other, enabling ERK phosphorylation in MEK-binding deficient mutants. Thus, associations among different scaffold proteins will add one further degree of regulation for an already tightly regulated cascade and could provide a novel means for manipulating ERK signals even with therapeutic purposes.La presente tesis doctoral titulada “Optimization of ERK signalling by transphosphorylation across different scaffold protein species: implication in cancer therapeutics” ha sido realizada en el Instituto de Biomedicna y Biotecnologia de Cantabria (IBBTEC) en el laboratorio de Regulacion espacial de las senales RAS/ERK en cancer gracias a la ayuda del Programa de personal investigador en formacion predoctoral en el area de biomedicina, biotecnologia y ciencias de la salud de la Universidad de Cantabria ( BOC 30.09.2015) y a los proyectos financiados por: CIBEROCIC ISCII, AECC, MINISTERIO DE ECONOMÍA Y COMPETITIVIDAD Durante el presente trabajo Ana Martin Vega ha realizado una estancia predoctoral de 3 meses en el laboratorio del Dr. David Engelberg en el instituto Alexander Silberman of Life Science en la Universidad Hebrea de Jerusalen, Israel, gracias a la financiacion para estancias predoctorales de la Universidad de Cantabri
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