76 research outputs found
Concurrent overexpression of amino acid permease AAP1(3a) and SUT1 sucrose transporter in pea resulted in increased seed number and changed cytokinin and protein levels
Using pea as our model crop, we sought to understand the regulatory control over the import of sugars and amino acids into the developing seeds and its importance for seed yield and quality. Transgenic peas simultaneously overexpressing a sucrose transporter and an amino acid transporter were developed. Pod walls, seed coats, and cotyledons were analysed separately, as well as leaves subtending developing pods. Sucrose, starch, protein, free amino acids, and endogenous cytokinins were measured during development. Temporal gene expression analyses (RT-qPCR) of amino acid (AAP), sucrose (SUT), and SWEET transporter family members, and those from cell wall invertase, cytokinin biosynthetic (IPT) and degradation (CKX) gene families indicated a strong effect of the transgenes on gene expression. In seed coats of the double transgenics, increased content and prolonged presence of cytokinin was particularly noticeable. The transgenes effectively promoted transition of young sink leaves into source leaves. We suggest the increased flux of sucrose and amino acids from source to sink, along with increased interaction between cytokinin and cell wall invertase in developing seed coats led to enhanced sink activity, resulting in higher cotyledon sucrose at process pea harvest, and increased seed number and protein content at maturity
Factores que inciden en la integración de la informática en las escuelas primarias: la capacitación docente
El presente trabajo tiene por finalidad dar a conocer algunos resultados parciales obtenidos en el marco del proyecto de investigación “Modelos de aplicación de la Informática en Centros Educativos”, aprobado y subsidiado por la Secretaría de Ciencia y Técnica de la UNRC.
El mencionado proyecto parte desde el supuesto de que la mayoría de los centros educativos de nivel primario de la región central del país, en general, no integra la informática atendiendo a las dimensiones político-educativa, sociocultural, socioeconómico-institucional y de su contexto comunitario, desaprovechando así el potencial que la computadora tiene para favorecer los procesos de enseñanza y de aprendizaje.
En este sentido, es que se comenzaron a analizar algunos de los factores que consideramos intervienen en todo proceso de integración de la Informática al ámbito educativo y en particular, en este trabajo, se explicita un análisis de las relaciones observadas entre el tipo de capacitación sobre informática que poseen los docentes de los centros educativos bajo estudio y el nivel de uso e integración pedagógica que se hace de la computadora en dichos centros.
A continuación, se presenta una contextualización del proyecto de investigación y la metodología de trabajo adoptada en el marco del mismo, algunas posturas relacionadas con el tema y a luz de las cuales se realiza el análisis, los ejes en torno a los cuales se agrupan los casos y algunas conclusiones al respecto.Red de Universidades con Carreras en Informática (RedUNCI
La informática en los centros educativos: entre el ideal y la acción
El presente trabajo brinda resultados obtenidos en el Proyecto de Investigación “Modelos de aplicación de la informática en los Centros Educativos” (perteneciente a la Universidad Nacional de Río Cuarto), en relación a las posturas que poseen los directivos de Centros Educativos de nivel primario en cuanto a la informática en la escuela y a las actividades que los profesionales encargados de los laboratorios de computación llevan a cabo en los mismos.
La incorporación de la Informática en los centros educativos no debe significar solamente la inversión en equipamiento de última generación; sino que se debe generar un plan de estrategias a nivel Estado e Institución, para que el laboratorio de computación se convierta en un espacio donde se lleven a cabo actividades que potencien el uso de la Informática como una herramienta pedagógica-didáctica, interrelacionada con las demás áreas curriculares.
En este sentido y como el objetivo principal de nuestro proyecto es identificar modelos de aplicación de la informática en los centros educativos, se consideró relevante conocer y analizar las opiniones de los directivos sobre la incorporación de la informática en las escuelas, ya que ellos cuentan entre sus funciones, la de diseñar e implementar planes o programas institucionales, distribuyendo y asignando recursos (tanto físicos como humanos). Asimismo, es un aspecto necesario conocer las actividades que los profesionales encargados de los laboratorios realizan en éstos, para así reflexionar sobre de qué manera realmente se utiliza la computadora en las escuelas muestreadas.
En esta ponencia entonces se presentan los resultados del análisis de la información recabada, a partir de entrevistas a directivos y docentes, para así reflexionar sobre las concepciones que los directivos poseen en torno a la incorporación de la informática en la escuela, y las actividades que efectivamente se realizan en el laboratorio de computación.Red de Universidades con Carreras en Informática (RedUNCI
La informática en los centros educativos: entre el ideal y la acción
El presente trabajo brinda resultados obtenidos en el Proyecto de Investigación “Modelos de aplicación de la informática en los Centros Educativos” (perteneciente a la Universidad Nacional de Río Cuarto), en relación a las posturas que poseen los directivos de Centros Educativos de nivel primario en cuanto a la informática en la escuela y a las actividades que los profesionales encargados de los laboratorios de computación llevan a cabo en los mismos.
La incorporación de la Informática en los centros educativos no debe significar solamente la inversión en equipamiento de última generación; sino que se debe generar un plan de estrategias a nivel Estado e Institución, para que el laboratorio de computación se convierta en un espacio donde se lleven a cabo actividades que potencien el uso de la Informática como una herramienta pedagógica-didáctica, interrelacionada con las demás áreas curriculares.
En este sentido y como el objetivo principal de nuestro proyecto es identificar modelos de aplicación de la informática en los centros educativos, se consideró relevante conocer y analizar las opiniones de los directivos sobre la incorporación de la informática en las escuelas, ya que ellos cuentan entre sus funciones, la de diseñar e implementar planes o programas institucionales, distribuyendo y asignando recursos (tanto físicos como humanos). Asimismo, es un aspecto necesario conocer las actividades que los profesionales encargados de los laboratorios realizan en éstos, para así reflexionar sobre de qué manera realmente se utiliza la computadora en las escuelas muestreadas.
En esta ponencia entonces se presentan los resultados del análisis de la información recabada, a partir de entrevistas a directivos y docentes, para así reflexionar sobre las concepciones que los directivos poseen en torno a la incorporación de la informática en la escuela, y las actividades que efectivamente se realizan en el laboratorio de computación.Red de Universidades con Carreras en Informática (RedUNCI
Reformism, Economic Liberalisation and Popular Mobilisation in Iran
Whereas in other MENA countries the impact of neo-liberal policies has been the subject of intense debate, there are at present few voices that directly analyse or critique its social and political consequences in Iran. This article seeks to address this lacuna by analysing the dynamics of reformism, economic liberalisation and popular mobilisation in Iran. It charts the country’s move from a post-revolutionary populism to a liberalised yet increasingly exclusivist model of politics and compares this to trajectories of economic liberalisation in Egypt. Two distinct outcomes of economic reform are analysed in the first part of the article: Socio-economic exclusion; and the contraction of political rights. In the second half, I investigate the ways successive post-war governments in Iran have packaged neo-liberal reforms, and how their re-imagining of the role of the state has led to differing levels of popular resistance. Finally I argue that under the present administration, political elites increasingly are oriented toward strengthening the state and seeking to limit opposition to their policies. However, the absence of neo-liberal hegemony in Iran means that growing mobilization on socio-economic issues is challenging these policies. The Right in Iranian politics is utilizing this mobilisation to present a populist challenge to the reformists in power
Techno-economic assessment of two novel feeding systems for a dry-feed gasifier in an IGCC plant with Pd-membranes for CO2 capture
This study focuses on the application of Pd-based membranes for CO[subscript 2] capture in coal fueled power plants. In particular, membranes are applied to Integrated Gasification Combined Cycle with two innovative feeding systems. In the first feeding system investigated, CO[subscript 2] is used both as fuel carrier and back-flushing gas for the candle filters, while in the second case N[subscript 2] is the fuel carrier, and CO[subscript 2] the back-flushing gas. The latter is investigated because current dry feed technology vents about half of the fuel carrier, which is detrimental for the CO[subscript 2] avoidance in the CO[subscript 2] case. The hydrogen separation is performed in membrane modules arranged in series; consistently with the IGCC plant layout, most of the hydrogen is separated at the pressure required to fuel the gas turbine. Furthermore, about 10% of the overall hydrogen permeated is separated at ambient pressure and used to post-fire the heat recovery steam generator. This layout significantly reduces membrane surface area while keeping low efficiency penalties.
The resulting net electric efficiency is higher for both feeding systems, about 39%, compared to 36% of the reference Selexol-based capture plant. The CO[subscript 2] avoidance depends on the type of feeding system adopted, and its amount of vented gas; it ranges from 60% to 98%. From the economic point of view, membrane costs are significant and shares about 20% of the overall plant cost. This leads in the more optimistic case to a CO[subscript 2] avoidance cost of 35 €/t[subscript CO2], which is slightly lower than the reference case.Seventh Framework Programme (European Commission) (Grant agreement no. 241342
From North Africa to Latin America and back: comparative findings and theoretical reflections
Taking the different case studies of the book together, one general observation stands out: Key agents of socioeconomic contention, including movements by organized labor and the unemployed that were important in the run-up to the uprisings and that saw their political opportunities open up in the immediate aftermath of the revolutions, have since been effectively marginalized as political actors. The concluding chapter reflects on the causes of this weakness of socioeconomic contention by identifying comparative insights that emerge from the contributions to this volume and by situating them in the context of broader comparative and theoretical debates on the relationship between social movements and political change. More specifically, the chapter first discusses Egypt’s and Tunisia’s post-revolutionary trajectories from a comparative perspective. Second, it discusses these comparative findings in the light of experiences in Latin America. Third, drawing again on comparative scholarship on Latin America, the chapter offers a theoretical interpretation of some of the main dynamics observed in Egypt and Tunisia based on the notion of a popular-sector incorporation crisis. Fourth and finally, the chapter concludes with general implications and an outlook
The Impact of Long-Term Exposure to Space Environment on Adult Mammalian Organisms: A Study on Mouse Thyroid and Testis
Hormonal changes in humans during spaceflight have been demonstrated but the underlying mechanisms are still unknown. To clarify this point thyroid and testis/epididymis, both regulated by anterior pituitary gland, have been analyzed on long-term space-exposed male C57BL/10 mice, either wild type or pleiotrophin transgenic, overexpressing osteoblast stimulating factor-1. Glands were submitted to morphological and functional analysis
Spinal Cord Injury Causes Sustained Disruption of the Blood-Testis Barrier in the Rat
There is a high incidence of infertility in males following traumatic spinal cord injury (SCI). Quality of semen is frequently poor in these patients, but the pathophysiological mechanism(s) causing this are not known. Blood-testis barrier (BTB) integrity following SCI has not previously been examined. The objective of this study was to characterize the effects of spinal contusion injury on the BTB in the rat. 63 adult, male Sprague Dawley rats received SCI (n = 28), laminectomy only (n = 7) or served as uninjured, age-matched controls (n = 28). Using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), BTB permeability to the vascular contrast agent gadopentate dimeglumine (Gd) was assessed at either 72 hours-, or 10 months post-SCI. DCE-MRI data revealed that BTB permeability to Gd was greater than controls at both 72 h and 10 mo post-SCI. Histological evaluation of testis tissue showed increased BTB permeability to immunoglobulin G at both 72 hours- and 10 months post-SCI, compared to age-matched sham-operated and uninjured controls. Tight junctional integrity within the seminiferous epithelium was assessed; at 72 hours post-SCI, decreased expression of the tight junction protein occludin was observed. Presence of inflammation in the testes was also examined. High expression of the proinflammatory cytokine interleukin-1 beta was detected in testis tissue. CD68+ immune cell infiltrate and mast cells were also detected within the seminiferous epithelium of both acute and chronic SCI groups but not in controls. In addition, extensive germ cell apoptosis was observed at 72 h post-SCI. Based on these results, we conclude that SCI is followed by compromised BTB integrity by as early as 72 hours post-injury in rats and is accompanied by a substantial immune response within the testis. Furthermore, our results indicate that the BTB remains compromised and testis immune cell infiltration persists for months after the initial injury
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