1,138 research outputs found

    Un currículo para el estudio de la historia de la ciencia en Secundaria : la experiencia del Seminario Orotava de Historia de la Ciencia

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    The curricula of two disciplines on History of Science at the High School level have been elaborated as part of the activities of a singular experience, Seminario Orotava de Historia de la Ciencia. The philosophy of the design considers science as an essential part of culture and interdisciplinarity as the most fitted method of teaching and learnign in a significative way

    Modelling the spatial and sectoral benefits of productivity enhancing innovations using a transport oriented multiregional IO framework: the ‘megatruck’ in Spain

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    We render operational the model outlined by Carter (1990) via the introduction of the research methods necessary for studying the spatial and sectoral (upstream and downstream) benefits of productivity-enhancing innovations within a real interregional input–output framework. As case study we examine the reduction in production costs derived from the adoption of longer and heavier vehicles in freight road transportation. We exploit a new Spanish regional table including a detailed disaggregation of the transportation sector. The productivity gains at the national level, resulting from a 30% reduction in transport costs, amount to 2.95% of the GVA at market prices. Results show that firms operating in this niche market appropriate most of the gross operation surplus (which increases by 10%), consistent with the existence of market power. The remaining transportation sectors see profits slightly worsened, suggesting limited substitution effects. A high regional heterogeneity exists because of the different input–output structuresThis work was supported by Ministerio de Fomento, Spain: [Grant Number P42-08

    A Bayesian model for anchovy (Engraulis encrasicolus): the combined forcing of man and environment

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    Fishery collapses frequently result from combined pressures of the environment and man, which are difficult to discern because of the complexities involved and our limited knowledge. Models to resolve this complexity often become too sophisticated, with too many assumptions and, consequently, with little capacity to predict beyond calibration data. In this paper we implement a different procedure where the model is kept simple and uncertainty accounts for the equation imperfectness to reproduce ecological complexity. Human and environmental forcing on an anchovy (Engraulis encrasicolus) stock are simulated with only six parameters plus their error terms, and the uncertainty is computed with Bayesian methods. The simple structure is able to reproduce the major dynamical features of this species in the Gulf of Ca´diz, including data on life stages and age structure that had no contact with the model. This is a distinct performance for a frugal approach working on a mid-trophic species and a positive instance where parsimony can simulate the interaction of man, fish and the environment, provided uncertainty is accounted for in the process.Publicado

    Evolution induced by dry minor mergers onto fast-rotator S0 galaxies

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    We analysed collisionless N-body simulations of intermediate and minor dry mergers onto S0s to test whether these mergers can generate S0 galaxies with kinematics intermediate between fast and slow rotators. We find that minor mergers induce a lower decrease of the global rotational support than encounters of lower mass ratios, which results in S0s with properties intermediate between fast and slow rotators. The resulting remnants are intrinsically more triaxial, less flattened, and span the whole range of apparent ellipticities up to ϵe0.8\epsilon_\mathrm{e} \sim 0.8. They do not show lower apparent ellipticities in random projections than initially; on the contrary, the formation of oval distortions and the disc thickening increase the percentage of projections at 0.4<ϵe<0.70.4 < \epsilon_\mathrm{e} < 0.7. In the experiments with S0b progenitor galaxies, minor mergers tend to spin up the bulge and to decrease slightly its intrinsic ellipticity, whereas in the cases of primary S0c galaxies they keep the rotational support of the bulge nearly constant and decrease significantly its intrinsic ellipticity. The remnant bulges remain nearly spherical (B/AC/A>0.9B/A \sim C/A > 0.9), but exhibit a wide range of triaxialities (0.20<T<1.000.20 < T < 1.00). In the plane of global anisotropy of velocities (δ\delta) vs. intrinsic ellipticity (ϵe,intr\epsilon_\mathrm{e,intr}), some of our models extend the linear trend found in previous major merger simulations towards higher ϵe,intr\epsilon_\mathrm{e,intr} values, while others depart from it. This is consistent with the wide dispersion exhibited by real S0s in this diagram compared with ellipticals, which follow the linear trend drawn by major merger simulations. The different trends exhibited by ellipticals and S0 galaxies in the δ\delta - ϵe\epsilon_\mathrm{e} diagram may be pointing to the different role played by major mergers in the build-up of each morphological type.Comment: Corrected typos. 20 pages, 14 figures. Accepted for publishing in A&

    Interest and Applicability of Meta-Heuristic Algorithms in the Electrical Parameter Identification of Multiphase Machines

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    Multiphase machines are complex multi-variable electro-mechanical systems that are receiving special attention from industry due to their better fault tolerance and power-per-phase splitting characteristics compared with conventional three-phase machines. Their utility and interest are restricted to the definition of high-performance controllers, which strongly depends on the knowledge of the electrical parameters used in the multiphase machine model. This work presents the proof-of-concept of a new method based on particle swarm optimization and standstill time-domain tests. This proposed method is tested to estimate the electrical parameters of a five-phase induction machine. A reduction of the estimation error higher than 2.5% is obtained compared with gradient-based approaches.Plan Estatal 2013-2016 Retos - Proyectos I+D+i DPI2013-44278-RPlan Estatal 2013-2016 Retos - Proyectos I+D+i DPI2016-76144-

    Tratamiento con talidomida en estomatitis aftosa recurrente en una paciente pediátrica

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    El uso de talidomia es controvertido y especialmente en población pediátrica, si bien es cierto las publicaciones disponibles avalan su uso en determinadas condiciones en las que la presencia de aftas bucales comprometa la calidad de vida de los pacientes y éstas no  hayan sido  resueltas  con los tratamientos habituales. En nuestro caso nos encontramos ante una paciente pediátrica donde la estomatitis aftosa condicionaba incluso su correcta alimentación, por este motivo y tras realizar las pruebas oportunas para determinar las causas de las mismas  se decide comenzar el tratamiento con talidomida.  Los resultados fueron muy positivos en cuanto a reducción de episodios aftosos pero los efectos adversos observados en la paciente condicionaron la suspensión del tratamiento. La implicación farmacéutica hizo posible una coordinación entre atención primaria y especializada, un asesoramiento tanto a personal sanitario como a la paciente y tutores legales, la adquisición del fármaco y la elaboración de una fórmula magistral adaptada a los cambios posológicos. Por otro lado el estrecho seguimiento de la paciente y de los efectos adversos hizo posible su suspensión en el momento en el que la relación beneficio/riesgo ya no era favorable.

    CHK1 expression in gastric cancer is modulated by p53 and RB1/E2F1: implications in chemo/radiotherapy response

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    This work is licensed under a Creative Commons Attribution 4.0 International License.-- et al.Radiation has a limited but relevant role in the adjuvant therapy of gastric cancer (GC) patients. Since Chk1 plays a critical function in cellular response to genotoxic agents, we aimed to analyze the role of Chk1 in GC as a biomarker for radiotherapy resistance. We analyzed Chk1 expression in AGS and MKN45 human GC cell lines by RT-QPCR and WB and in a small cohort of human patient's samples. We demonstrated that Chk1 overexpression specifically increases resistance to radiation in GC cells. Accordingly, abrogation of Chk1 activity with UCN-01 and its expression with shChk1 increased sensitivity to bleomycin and radiation. Furthermore, when we assessed Chk1 expression in human samples, we found a correlation between nuclear Chk1 accumulation and a decrease in progression free survival. Moreover, using a luciferase assay we found that Chk1's expression is controlled by p53 and RB/E2F1 at the transcriptional level. Additionally, we present preliminary data suggesting a posttranscriptional regulation mechanism, involving miR-195 and miR-503, which are inversely correlated with expression of Chk1 in radioresistant cells. In conclusion, Chk1/microRNA axis is involved in resistance to radiation in GC, and suggests Chk1 as a potential tool for optimal stratification of patients susceptible to receive adjuvant radiotherapy after surgery.This work was supported by Instituto de Salud Carlos III–Fondo de Investigación Sanitaria (PS09/1988 to ISP; PI11-00949, pI014-1495 and Feder Funds to RP); Comunidad Autónoma de Madrid-Universidad Autónoma de Madrid (CCG10-UAM/BIO-5871 to ISP); Fundación Leticia Castillejo Castillo and Ministerio de Ciencia e Innovación (SAF2012-30862 to RSP), Spain. JBI was supported by a fellowship from Catedra Isaac Costero, funded by Banco Santander UAM and is a doctoral student from a double doctorate program in Molecular Biosciences (UAM) and in Biomedical Sciences, (UNAM) and received fellowship CVU:607546 from CONACYT.Peer Reviewe

    Tratamiento con talidomida en estomatitis aftosa recurrente en una paciente pediátrica

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    El uso de talidomia es controvertido y especialmente en población pediátrica, si bien es cierto las publicaciones disponibles avalan su uso en determinadas condiciones en las que la presencia de aftas bucales comprometa la calidad de vida de los pacientes y éstas no  hayan sido  resueltas  con los tratamientos habituales. En nuestro caso nos encontramos ante una paciente pediátrica donde la estomatitis aftosa condicionaba incluso su correcta alimentación, por este motivo y tras realizar las pruebas oportunas para determinar las causas de las mismas  se decide comenzar el tratamiento con talidomida.  Los resultados fueron muy positivos en cuanto a reducción de episodios aftosos pero los efectos adversos observados en la paciente condicionaron la suspensión del tratamiento. La implicación farmacéutica hizo posible una coordinación entre atención primaria y especializada, un asesoramiento tanto a personal sanitario como a la paciente y tutores legales, la adquisición del fármaco y la elaboración de una fórmula magistral adaptada a los cambios posológicos. Por otro lado el estrecho seguimiento de la paciente y de los efectos adversos hizo posible su suspensión en el momento en el que la relación beneficio/riesgo ya no era favorable.
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