40 research outputs found

    Políticas públicas, autonomía y participación docente en contextos de transformación y cambio

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    Son muy escasos los organismos internacionales que se preocupan por la situación de los docentes: en América Latina la Red Estrado es uno de los contados colectivos que realiza estudios, investigaciones y propuestas por mejorar la condición humana y profesional de los educadores. En el Ecuador, en sus pocos años de funcionamiento, la Red Estrado ha tenido una presencia muy poco activa para denunciar los problemas y dificultades que afectan a los docentes, dar a conocer las fortalezas y cualidades de quienes educan a los ecuatorianos del presente y del futuro y proponer acciones concretas que aseguren el desarrollo de los integrantes del magisterio. Esta organización de la sociedad civil está integrada por un selecto grupo de académicos pertenecientes a varias universidades, quienes con una actitud totalmente desinteresada y altruista, con el apoyo de sus respectivos centros de educación superior, han organizado algunos eventos nacionales, han publicado varios libros sobre la situación docente y, de manera excepcional, han colocado este tema en el imaginario nacional, a fin de dar a conocer los aspectos relacionados con la formación inicial, el ejercicio de la carrera, las condiciones de salud y trabajo, la formación permanente, los problemas salariales, la evaluación y los demás asuntos que se relacionan con la trayectoria profesional de los educadores. El libro políticas públicas, autonomía y participación docente en contextos de transformación y cambio, que se pone a consideración de los lectores, contiene varios estudios e investigaciones llevados a cabo en estos años por algunos docentes de centros educativos ecuatorianos y otros países de América Latina

    Changes in cGMP Levels Affect the Localization of EGL-4 in AWC in Caenorhabditis elegans

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    The Protein Kinase G, EGL-4, is required within the C. elegans AWC sensory neurons to promote olfactory adaptation. After prolonged stimulation of these neurons, EGL-4 translocates from the cytosol to the nuclei of the AWC. This nuclear translocation event is both necessary and sufficient for adaptation of the AWC neuron to odor. A cGMP binding motif within EGL-4 and the Gα protein ODR-3 are both required for this translocation event, while loss of the guanylyl cyclase ODR-1 was shown to result in constitutively nuclear localization of EGL-4. However, the molecular changes that are integrated over time to produce a stably adapted response in the AWC are unknown. Here we show that odor-induced fluctuations in cGMP levels in the adult cilia may be responsible in part for sending EGL-4 into the AWC nucleus to produce long-term adaptation. We found that reductions in cGMP that result from mutations in the genes encoding the cilia-localized guanylyl cyclases ODR-1 and DAF-11 result in constitutively nuclear EGL-4 even in naive animals. Conversely, increases in cGMP levels that result from mutations in cGMP phosphodiesterases block EGL-4 nuclear entry even after prolonged odor exposure. Expression of a single phosphodiesterase in adult, naive animals was sufficient to modestly increase the number of animals with nuclear EGL-4. Further, coincident acute treatment of animals with odor and the phosphodiesterase inhibitor 3-isobutyl-1-methylxanthine (IBMX) decreased the number of animals with nuclear EGL-4. These data suggest that reducing cGMP levels in AWC is necessary and even partially sufficient for nuclear translocation of EGL-4 and adaptation as a result of prolonged odor exposure. Our genetic analysis and chemical treatment of C. elegans further indicate that cilia morphology, as defined by fluorescent microscopic observation of the sensory endings, may allow for odor-induced fluctuations in cGMP levels and this fluctuation may be responsible for sending EGL-4 into the AWC nucleus

    AI is a viable alternative to high throughput screening: a 318-target study

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    : High throughput screening (HTS) is routinely used to identify bioactive small molecules. This requires physical compounds, which limits coverage of accessible chemical space. Computational approaches combined with vast on-demand chemical libraries can access far greater chemical space, provided that the predictive accuracy is sufficient to identify useful molecules. Through the largest and most diverse virtual HTS campaign reported to date, comprising 318 individual projects, we demonstrate that our AtomNet® convolutional neural network successfully finds novel hits across every major therapeutic area and protein class. We address historical limitations of computational screening by demonstrating success for target proteins without known binders, high-quality X-ray crystal structures, or manual cherry-picking of compounds. We show that the molecules selected by the AtomNet® model are novel drug-like scaffolds rather than minor modifications to known bioactive compounds. Our empirical results suggest that computational methods can substantially replace HTS as the first step of small-molecule drug discovery

    A História da Alimentação: balizas historiográficas

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    Os M. pretenderam traçar um quadro da História da Alimentação, não como um novo ramo epistemológico da disciplina, mas como um campo em desenvolvimento de práticas e atividades especializadas, incluindo pesquisa, formação, publicações, associações, encontros acadêmicos, etc. Um breve relato das condições em que tal campo se assentou faz-se preceder de um panorama dos estudos de alimentação e temas correia tos, em geral, segundo cinco abardagens Ia biológica, a econômica, a social, a cultural e a filosófica!, assim como da identificação das contribuições mais relevantes da Antropologia, Arqueologia, Sociologia e Geografia. A fim de comentar a multiforme e volumosa bibliografia histórica, foi ela organizada segundo critérios morfológicos. A seguir, alguns tópicos importantes mereceram tratamento à parte: a fome, o alimento e o domínio religioso, as descobertas européias e a difusão mundial de alimentos, gosto e gastronomia. O artigo se encerra com um rápido balanço crítico da historiografia brasileira sobre o tema

    Leukocyte Homing, Fate, and Function Are Controlled by Retinoic Acid

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    Although vitamin A was recognized as an “anti-infective vitamin” over 90 years ago, the mechanism of how vitamin A regulates immunity is only beginning to be understood. Early studies which focused on the immune responses in vitamin A-deficient (VAD) animals clearly demonstrated compromised immunity and consequently increased susceptibility to infectious disease. The active form of vitamin A, retinoic acid (RA), has been shown to have a profound impact on the homing and differentiation of leukocytes. Both pharmacological and genetic approaches have been applied to the understanding of how RA regulates the development and differentiation of various immune cell subsets, and how RA influences the development of immunity versus tolerance. These studies clearly show that RA profoundly impacts on cell- and humoral-mediated immunity. In this review, the early findings on the complex relationship between VAD and immunity are discussed as well as vitamin A metabolism and signaling within hematopoietic cells. Particular attention is focused on how RA impacts on T-cell lineage commitment and plasticity in various diseases

    Front Plate Manufacturing Process Improvement at Primetals

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    The objective of this MQP was to optimize the manufacturing process of the front plate while reducing costs, utilizing state of the art high speed machining, and the Taylor Tool Life Equation. The methods included utilizing axiomatic design, high speed machining, and program simulations. The results showed that new drilling tools and a new tool path reduced the machining time by about 50%. An economic analysis was performed to determine the cost savings due to the reduced machine time. In conclusion, the application of high speed machining methods and tool path simulation yielded a substantial annual savings for the company

    CCR6-Dependent Positioning of Memory B Cells Is Essential for Their Ability To Mount a Recall Response to Antigen

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    Chemokine-dependent localization of specific B cell subsets within the immune microarchitecture is essential to insure successful cognate interactions. While cognate interactions between T cells and memory B cells (B(mem))() are essential for the secondary humoral immune responses, the chemokine response patterns of B(mem) cells are largely unknown. In contrast to naïve B cells, this study shows that antigen-specific B(mem) cells have heightened expression of CCR6 and a selective chemotactic response to the CCR6 ligand, CCL20. While CCR6 appears be non-essential for the initial clonal expansion and maintenance of B(mem), CCR6 is essential for the ability of B(mem) to respond to a recall response to their cognate antigen. This dependency was deemed intrinsic by studies in CCR6-deficient mice and in bone-marrow chimeric mice where CCR6 deficiency was limited to the B cell lineage. Finally, the mis-positioning of CCR6-deficient B(mem) was revealed by immunohistological analysis with an altered distribution of CCR6-deficient B(mem) from the marginal and perifollicular to the follicular/germinal center area

    Positionality in Teaching: Implications for Advancing Social Justice

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    Teaching classes concerned with justice and equity led us to understand that we must model justice and equity in all of our work. In order to ask students to be vulnerable in talking about how they have been exposed to, and impacted by, society’s messages about race, gender, and sexual identity, we have a responsibility to first demonstrate that vulnerability ourselves. Thus, our work is more about “being” than “doing.” Modeling honest self-assessment allows us to ask students to be reflective about their relationship to power, privilege, and oppression. A reader hesitating to do this work should remember that analyzing power imbalances, misshapen structures, and hidden assumptions are familiar critical thinking tasks. If talking about our own mistakes, struggles, and fears is central to the curriculum, that lessens the fear of making mistakes in a new endeavor and even normalizes and values these moments. Just as students benefit from a new openness to authentic stories of others, and a deeper understanding of their own stories, so are teachers’ lives enriched thereby
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