30 research outputs found

    Experiencia en el uso del asistente matemático derive, en la solución de problemas físicos y/o geométricos

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    En este trabajo se tratarán problemas, en los cuales se tendrá en cuenta el aspecto de modelación, resolución e interpretación de resultados, donde predomina el análisis geométrico en cada situación. La obtención de estos resultados será sobre la base de la aplicación de las nuevas tecnologías, que favorecen el aprendizaje del estudiante y estimulan los procesos de creación y abstracción, permitiendo realizar operaciones con rapidez y exactitud. Además facilitan el intercambio ágil de información con el ordenador, aprovechando las capacidades tanto simbólicas como gráficas de los Asistentes Matemáticos (en este caso DERIVE)

    Lo glocal y el turismo. Nuevos paradigmas de interpretación.

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    El estudio del turismo se realiza desde múltiples escalas y enfoques, este libro aborda muchos temas que es necesario discutir desde diversas perspectivas; es el caso de la reflexión sobre la propia disciplina y sus conceptos, así como los asuntos específicos referidos al impacto territorial, los tipos de turismo, las cuestiones ambientales, el tema de la pobreza, la competitividad, las políticas públicas, el papel de las universidades, las áreas naturales protegidas, la sustentabilidad, la cultura, el desarrollo, la seguridad, todos temas centrales documentados y expuestos con originalidad y dominio del asunto. Lo multiescalar es básico para la comprensión del sistema turístico, sistema formado de procesos globales, regionales y locales. El eje de discusión del libro es lo glocal, esa interacción entre lo nacional y local con lo global

    Genome-Wide Analysis of Factors Affecting Transcription Elongation and DNA Repair: A New Role for PAF and Ccr4-Not in Transcription-Coupled Repair

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    RNA polymerases frequently deal with a number of obstacles during transcription elongation that need to be removed for transcription resumption. One important type of hindrance consists of DNA lesions, which are removed by transcription-coupled repair (TC-NER), a specific sub-pathway of nucleotide excision repair. To improve our knowledge of transcription elongation and its coupling to TC-NER, we used the yeast library of non-essential knock-out mutations to screen for genes conferring resistance to the transcription-elongation inhibitor mycophenolic acid and the DNA-damaging agent 4-nitroquinoline-N-oxide. Our data provide evidence that subunits of the SAGA and Ccr4-Not complexes, Mediator, Bre1, Bur2, and Fun12 affect transcription elongation to different extents. Given the dependency of TC-NER on RNA Polymerase II transcription and the fact that the few proteins known to be involved in TC-NER are related to transcription, we performed an in-depth TC-NER analysis of a selection of mutants. We found that mutants of the PAF and Ccr4-Not complexes are impaired in TC-NER. This study provides evidence that PAF and Ccr4-Not are required for efficient TC-NER in yeast, unraveling a novel function for these transcription complexes and opening new perspectives for the understanding of TC-NER and its functional interconnection with transcription elongation

    Perceptions of teachers and directors about the factors that promote or constrain environmental education in schools of Metropolitan Area of Buenos Aires, Argentina

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    El trabajo aborda las percepciones de docentes y directores de escuelas acerca delos factores que promueven u obstaculizan una educación ambiental compleja, generadora de conocimientos, con dispositivos participativos y orientados a la equidad en instituciones educativas del Área Metropolitana de Buenos Aires (Argentina). Como resultado se observaron experiencias heterogéneas y voluntad de instalar nuevas prácticas, pero con factores que limitan el cambio: pautas culturales arraigadas; deficiencias en la capacitación docente, en cuanto a las políticas públicas; poca claridad en las definiciones sobre los objetivos de la educación ambiental, su abordaje curricular y los dispositivos pedagógicos. Prevalecen enfoques fragmentados, naturalistas y la ausencia de una visión crítica. A nivel institucional, se discute lapertinencia de implementar prácticas sustentables en el aula. Las propias percepciones también operan como obstáculos. Todo esto dificulta la adopción de nuevas acciones de educación ambiental con el ímpetu necesario para sostenerlas en el tiempo.The paper examines the perceptions of teachers and directors regarding the factors that promote or constrain complex environmental education, which generates knowledge, with participatory devices and oriented to equity in educational institutions in Metropolitan Area of Buenos Aires (Argentina). As result, we detected heterogeneous experiences and willingness to set new practices up. But there are factors limiting the change: deep-rooted cultural customs; shortcomings in terms of teacher training; in public policies a lack of clarity about environmental education objectives, curricular approach and pedagogical devices. Fragmented and naturalists approaches, and lack of a critical perspective prevail. At the institutional level, the relevance of implementing sustainable practices in classroom is discussed. Perceptions also operate as obstacles. All this hinders the adoption of new environmental education actions and the momentum needed to sustain them over time.Fil: Saidon, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires; ArgentinaFil: Claverie, Julieta Andrea. Universidad Nacional de Tres de Febrero. Nucleo Interd de Formación y Est P/e/des D/l/educ; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    Global urban environmental change drives adaptation in white clover.

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    Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale

    Global urban environmental change drives adaptation in white clover

    Get PDF
    Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale

    On the planarity of Peano generalized continua: An extension of a theorem of S. Claytor

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    We extend a theorem of S. Claytor in order to characterize the Peano generalized continua which are embeddable into the 2-sphere. We also give a characterization of the Peano generalized continua which admit closed embeddings in the Euclidean plane
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