Contribution of the radiative heat transfer mechanism to the total thermal conductivity of anisotropic cellular materials

Con el fin de comprender y mejorar el comportamiento de los materiales celulares poliméricos como aislantes térmicos, este trabajo centra su estudio en la contribución del mecanismo de transferencia de calor por radiación en la conductividad térmica total de materiales celulares con diferentes coeficientes de anisotropía. El estudio comienza con una caracterización de los materiales seleccionados, materiales celulares en base poliestireno fabricados mediante un proceso de extrusión, en términos de su estructura celular y su conductividad térmica en función de la temperatura. Seguidamente, se determina la contribución radiativa para cada una de las tres direcciones principales de los materiales mediante tres metodologías independientes: espectroscopía de infrarrojos por transformada de Fourier (FTIR), derivación a partir de la conductividad total usando modelos teóricos, y derivación teórica a partir del modelo propuesto por Glicksman. Finalmente, se discuten los resultados obtenidos mediante las diferentes metodologías y se estudia el efecto de la anisotropía en el mecanismo de trasmisión del calor por radiación, estableciendo correlaciones con la estructura de los materiales.In order to understand and improve the performance of polymeric cellular materials as heat insulators, the contribution of the radiative transfer mechanism to the total thermal conductivity in cellular materials with different ratios of anisotropy is studied. Cellular materials based on polystyrene produced by an extrusion process are considered. The study begins with a characterization of the selected materials in terms of cellular structure and thermal conductivity as a function of temperature. Then, the radiative contribution for each of the three principal directions in the materials is obtained by three independent methodologies: Fourier Transform Infrared (FTIR) spectroscopy, derivation from the total conductivity using theoretical models, and theoretical calculation from the model proposed by Glicksman. Finally, the results yielded by these methodologies and their differences in the three principal directions are discussed, The effect of anisotropy on the radiative heat transfer mechanism is also analysed establishing correlations with the cellular structure.Departamento de Física de la Materia Condensada, Cristalografía y MineralogíaMáster en Físic

Duty of Care and Risk Management for Institutions of Higher Education

Institutions of Higher Education (IHE) authority has evolved from nearly absolute power in the hands of colleges and universities to an approach more focused on individual students and their rights. Yet, while college authority over campus life and student conduct has diminished, the duty of care required in the form of additional student affairs services has increased. The history of the complicated relationship between students and IHE starts with the concept “in loco parentis,” which is Latin for “in place of parents.” A lack of proper and continued risk assessment and a lack of effective and manageable policies and procedures assessment in relation to duty of care can lead to lawsuits, court-mandated change, and worse—student harm. Given the complexities and the challenges of managing today’s higher education institutions, leaders must be willing to adopt new leadership practices to be able to respond to a quick-changing environment to preserve internal decision-making and avoiding the dictation of policy by external entities. The study will utilize a qualitative research method to examine the experiences of nine community college leaders in the state of Washington. A main theme that emerged was shifting campus cultures and demographics that necessitates thorough evaluation of IHR policies and procedures. The participants provided insight and recommendations for institutional alignment with current law, trends, and best practices

El intelectual y la pantalla

Depto. de Sociología AplicadaFac. de Ciencias Políticas y SociologíaTRUEpu

Las políticas de integración nacional que deben ser implementadas por la fuerza pública

La integración nacional es uno de los siete objetivos nacionales permanentes del estado ecuatoriano y constituye un proceso que se forja al fragor de intereses contrapuestos o antagónicos, fruto de una realidad y evolución geográfica, antropología, historia, económica, política, social, cultura, etc., propia y diferente de un grupo social respecto a otro. eLa diversidad natural de cada manifestación de organización social, partiendo del hombre considerado individualmente, la familia, los pueblos, las naciones y las organizaciones multinacionales, constituye un serio y muchas veces insalvable obstáculo para lograr una verdadera integración e identidad común que las robustezca e identifique frente a organizaciones similares

The arogenate dehydratase ADT2 is essential for seed development in Arabidopsis

Phenylalanine (Phe) biosynthesis in plants is a key process, as Phe serves as precursor of proteins and phenylpropanoids. The prephenate pathway connects chorismate, final product of the shikimate pathway, with the biosynthesis of Phe and Tyr. Two alternative routes of Phe biosynthesis have been reported: one depending of arogenate, and the other of phenylpyruvate. Whereas the arogenate pathway is considered the main route, the role of the phenylpyruvate pathway remains unclear. Here, we report that the deficiency in ADT2, a bifunctional arogenate dehydratase (ADT)/ prephenate dehydratase (PDT) enzyme, causes embryo arrest and seed abortion. This result makes a clear distinction between the essential role of ADT2 and the five remaining ADTs from Arabidopsis, which display mostly overlapping functions. We have found that PHA2, a monofunctional PDT from yeast, restores the adt2 phenotype when is targeted within the plastids, but not when is expressed in the cytosol. Similar results can be obtained by expressing ADT3, a monofunctional ADT. These results suggest that Phe can be synthesized from phenylpyruvate or arogenate when the bifunctional ADT2 is replaced by other ADT or PDT enzymes during seed formation, highlighting the importance of Phe for embryo development, and providing further insights into the plasticity of Phe biosynthesis.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Las políticas de integración nacional que deben ser implementadas por la fuerza pública

La integración nacional es uno de los siete objetivos nacionales permanentes del estado ecuatoriano y constituye un proceso que se forja al fragor de intereses contrapuestos o antagónicos, fruto de una realidad y evolución geográfica, antropología, historia, económica, política, social, cultura, etc., propia y diferente de un grupo social respecto a otro. eLa diversidad natural de cada manifestación de organización social, partiendo del hombre considerado individualmente, la familia, los pueblos, las naciones y las organizaciones multinacionales, constituye un serio y muchas veces insalvable obstáculo para lograr una verdadera integración e identidad común que las robustezca e identifique frente a organizaciones similares

Cloud-Based Collaborative 3D Modeling to Train Engineers for the Industry 4.0

In the present study, Autodesk Fusion 360 software (which includes the A360 environment) is used to train engineering students for the demands of the industry 4.0. Fusion 360 is a tool that unifies product lifecycle management (PLM) applications and 3D-modeling software (PDLM—product design and life management). The main objective of the research is to deepen the students’ perception of the use of a PDLM application and its dependence on three categorical variables: PLM previous knowledge, individual practices and collaborative engineering perception. Therefore, a collaborative graphic simulation of an engineering project is proposed in the engineering graphics subject at the University of La Laguna with 65 engineering undergraduate students. A scale to measure the perception of the use of PDLM is designed, applied and validated. Subsequently, descriptive analyses, contingency graphical analyses and non-parametric analysis of variance are performed. The results indicate a high overall reception of this type of experience and that it helps them understand how professionals work in collaborative environments. It is concluded that it is possible to respond to the demand of the industry needs in future engineers through training programs of collaborative 3D modeling environments

Biochemical regulation of arginine biosynthesis in plants

Arginine plays a relevant role in plant metabolism due to its importance as building block of proteins but also as precursor of multiple secondary metabolites, polyamines and nitric oxide. Importantly, arginine frequently plays an essential role as a major nitrogen storage form in seeds and other vegetative tissues and its mobilization provides an efficient flux of nitrogen for different physiological processes [1][2][3]. Despite its importance, the biochemical regulation and kinetics of the enzymes involved in arginine biosynthesis remains poorly characterized in plants. In this work, we provide new knowledge about the biochemical regulation of the three enzymes involved in the last steps of the arginine pathway: ornithine transcarbamoylase (OTC), argininosuccinate synthetase (ASSY), and argininosuccinate lyase (ASL). Our results indicate that these enzymes are regulated by the concentration of different amino acids and metabolites, including arginine, suggesting that feedback regulatory loops could play and important role in the homeostasis of this amino acid. Besides, these regulatory mechanisms seem to have been subjected to a progressive refinement during the evolution of land plants, pointing towards a coevolution with the higher requirements of arginine in seed plants.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Soja y minería: dos lecturas territoriales en la Argentina reciente

This paper analyzes the recent dynamics of two types of specialization in natural resources-intensive activities: one, of an agricultural nature, refers to the soybean complex; and the other, to metal mining. With quantitative methods, a stylized reading was made about those features that influence regional labor markets and provincial public finances, in which localized productive chains, regulatory frameworks, and national public policies were explored .The results show productive reconfigurationsthat have not generated significant increases in local employment structures, although they have caused considerable qualitative alterations , while the territorial redistributive effect of taxation mechanisms has had different impacts in the cases considered.Este artigo analisa a dinâmica recente de dois tipos de especialização em atividades intensivas em recursos naturais: uma, de natureza agrícola, refere-se ao complexo de soja; e a outra, a mineração de metais. Com a ajuda de métodos quantitativos, foi feita uma leitura estilizada das características que influenciam os mercados de trabalho regionais e as finanças públicas provinciais, na qual foram exploradas ligações produtivas localizadas, marcos regulatórios e políticas públicas nacionais. Os resultados mostram reconfigurações produtivas que não geraram aumentos significativos nas estruturas locais de emprego, embora tenha ocorrido consideráveis alterações qualitativas, enquanto o efeito redistributivo territorial dos mecanismos de tributação teve impactos diversos e diferentes nos casos considerados.Este trabajo analiza las dinámicas recientes de dos tipos de especializaciones en actividades intensivas en recursos naturales: una, de carácter agrícola, remite al complejo sojero; y la otra, a la minería metalífera. Con el auxilio de métodos cuantitativos se realizó una lectura estilizada sobre aquellos rasgos que ejercen influencia en los mercados de trabajo regionales y en las finanzas públicas provinciales, en la cual se exploraron encadenamientos productivos localizados, marcos regulatoriosy políticas públicas nacionales. Los resultados muestran reconfiguraciones productivas que no han generado aumentos significativos en las estructuras locales de empleo, aunque sí alteraciones cualitativas considerables, a su vez que el efecto redistributivo territorial de los mecanismos fiscales de tributación ha tenido impactos diversos y distintos en los casos considerados