12 resultados para 42496
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This paper proposes and synthesizes from previous design science(DS) methodological literature a structured and detailed DS Roadmap for the conduct of DS research. The Roadmap is a general guide for researchers to carry out DS research by suggesting reasonably detailed activities.Though highly tentative, it is believed the Roadmap usefully inter-relates many otherwise seemingly disparate, overlapping or conflicting concepts. It is hoped the DS Roadmap will aid in the planning, execution and communication of DS research,while also attracting constructive criticism, improvements and extensions. A key distinction of the Roadmap from other DS research methods is its breadth of coverage of DS research aspects and activities; its detail and scope. We demonstrate and evaluate the Roadmap by presenting two case studies in terms of the DS Roadmap.
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The activity of Cr20~ in Cr20~-A12Oa solid solution has been determined in the temperature range 800~176 from electromotive force measurements on the solid oxide galvanic cell Pt,Cr + Cr2OJY~O~-ThO2/Cr + Cr~A12-xO~,Pt The activities of Cr203 and A120~ in the solid solution show both positive and negative deviations from Raoult's law. The heat and entropy of mixing of the solid Solution obtained from the temperature dependence of the emf can be expressed as AH = XCr203XA1203 [31,700Xcrzo3 -}- 37,470XA1203] J mole -I hS = -- 1.8R [Xcr2o3 In Xcr2o3 + XA12o3 In XAaos]The entropy of mixing is 10% lower than that predicted by the Temkin model.The large positive heat of mixing in the Cr2Os-A12Oa solid solution, however, suggests that this apparent: entropy discrepancy originates with the clustering of positive ions on the cation sublattice. The asymmetric miscibility gap exhibited in the CrzOa-A12Oa system below 900~ is consistent with the thermodynamic data trends recorded at the more elevated temperatures.
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磷脂酰甘油(phosphatidylglycerol, PG)是类囊体膜(也叫光合膜)中唯一的一种磷脂。在蓝藻中,PG的合成途径为:磷脂酸(phosphatidic acid, PA)胞嘧啶双磷酸-二酰基甘油 (cytidine diphosphate diacylglycerol, CDP-DAG) 磷酸磷脂酰甘油 (phosphatidylglycerol phosphate, PGP)PG。其中最后一步反应是由PGP去磷酸化而生成PG,催化该反应的是PGP磷酸酶。然而迄今为止,PGP磷酸酶还没有在蓝藻和高等植物中得到克隆和鉴定。本工作在鱼腥藻Anabaena sp. PCC7120中通过将一个可能编码PGP磷酸酶的基因(alr1715)进行突变,获得缺失PG的突变体。与野生型相比,该突变体PG的含量降低了30%左右。突变后的蓝藻藻丝发黄、生长缓慢,叶绿素含量降低。整体细胞的光合作用活性、光系统II(photosystem II,PSII)的放氧活性以及PSII反应中心的光能转化效率显著下降,传递给PSII的激发能减少。
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sermon text; MS Word document
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Esta investigación intenta facilitar la comprensión del proceso de aprendizaje de una segunda lengua y los posibles mecanismos del lenguaje involucrados, a partir del problema concreto de la adquisición del 'present perfect simple' en inglés para los hablantes del español.. El trabajo consta de dos partes centrales. La primera, dedicada a los fundamentos teóricos en los que se apoya el estudio, y la segunda, dedicada a un aproximación empírica, en donde se realizan varios estudios con distintos tipos de materiales que ponen a prueba las hipótesis de partida. Se formulan dos tipos de análisis con este fin: dos cuestionarios y tres experimentos. Ambos se centran tareas de reconocimiento y de producción del 'present perfect simple' y de sus usos.. Es necesario comprender que las dificultades de aprendizaje de algunos conocimientos, como el uso del 'present simple', radican en su dimensión conceptual, y no en su complejidad sintáctica o morfológica. Por esta razón, La autora considera indispensable comprender la naturaleza de los problemas de enseñanza de segundas lenguas para poder pensar así una práctica concienzuda de la docencia..
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Background Tax policy is considered the most effective strategy to reduce tobacco consumption and prevalence. Tax avoidance and tax evasion therefore undermine the effectiveness of tax policies and result in less revenue for governments, cheaper prices for smokers and increased tobacco use. Tobacco smuggling and illicit tobacco trade have probably always existed, since tobacco's introduction as a valuable product from the New World, but the nature of the trade has changed. Methods This article clarifies definitions, reviews the key issues related to illicit trade, describes the different ways taxes are circumvented and looks at the size of the problem, its changing nature and its causes. The difficulties of data collection and research are discussed. Finally, we look at the policy options to combat illicit trade and the negotiations for a WHO Framework Convention on Tobacco Control (FCTC) protocol on illicit tobacco trade. Results Twenty years ago the main type of illicit trade was large-scale cigarette smuggling of well known cigarette brands. A change occurred as some major international tobacco companies in Europe and the Americas reviewed their export practices due to tax regulations, investigations and lawsuits by the authorities. Other types of illicit trade emerged such as illegal manufacturing, including counterfeiting and the emergence of new cigarette brands, produced in a rather open manner at well known locations, which are only or mainly intended for the illegal market of another country. Conclusions The global scope and multifaceted nature of the illicit tobacco trade requires a coordinated international response, so a strong protocol to the FCTC is essential. The illicit tobacco trade is a global problem which needs a global solution.
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En el contexto actual, en los planes de estudio de los grados se incluye la evaluación continua como parte fundamental de la evaluación. En este trabajo se resumen las principales conclusiones y aspectos destacados del debate de los trabajos presentados en la mesa 12 de comunicaciones orales de las Jornadas de Redes de Investigación en Docencia Universitaria desarrollada en la Universidad de Alicante durante los días 3 y 4 de Julio de 2014. Entre las herramientas que han mostrado resultados positivos en las encuestas al alumnado está la autoevaluación en sus distintas formas. Además, resulta de utilidad en diversos tipos de asignaturas, siempre con resultados destacables, y permite adecuarse al número de alumnos o alumnas matriculadas, tanto para grupos pequeños como numerosos. La autoevaluación se aprecia como herramienta de evaluación y también de aprendizaje. Asimismo, se ha enfatizado el uso de las nuevas tecnologías en el proceso de enseñanza-aprendizaje.