Diseño y construcción del modelo a escala de un aerogenerador de eje horizontal para estudios experimentales

En los últimos años, en nuestra región, fundamentalmente Brasil, Chile, Uruguay y Argentina han impulsado fuertemente el desarrollo e instalación de aprovechamientos eólicos, debido a que generan un menor impacto ambiental si se compara con otras fuentes de energía. Con el objeto de optimizar el funcionamiento de los aerogeneradores individualmente o en un parque eólico, es fundamental el estudio de la interacción de la estructura de los mismos y la capa límite atmosférica. Una de las formas de estudiar este comportamiento es mediante ensayos experimentales en túneles de viento utilizando modelos a escala reducida. En este trabajo se describen las etapas de diseño y construcción del modelo a escala de un generador eólico de tres palas de eje horizontal. A partir de los aspectos aerodinámicos vinculados a este tipo de dispositivo, se diseñaron los componentes del aerogenerador y se evaluaron un conjunto de parámetros relacionados al funcionamiento y eficiencia del modelo. El modelo fue construido usando la técnica de impresión 3D de las componentes e incluye un dispositivo para el posicionamiento relativo de las palas con relación a la dirección del viento incidente. Finalmente, el modelo fue montado en el túnel de viento “Jacek Gorecki" de la UNNE y se realizaron ensayos que permitieron una primera evaluación de las características de funcionamiento del aerogenerador a través de la medición de RPM, potencia y torque. Los ensayos se realizaron con viento incidente uniforme considerando dos velocidades distintas; 5,26 m/s y 6,76 m/s. El ángulo que determina la posición de las palas con respecto al viento incidente ha sido modificado para obtener los valores de los parámetros respectivos correspondientes a cada situación.Fil: Milich, Franco G.. Universidad Nacional del NordesteFil: Alvarez y Alvarez, Gisela M. . Universidad Nacional del NordesteFil: Chuaire, Mauricio L.. Universidad Nacional del NordesteFil: Veroli, Cesar G. . Universidad Nacional del NordesteFil: Wittwer, Adrián R.. Universidad Nacional del Nordest

State capacity and the quality of policies : revisiting the relationship between openness and government size

Fil: Franco Chuaire, María. Universidad de San Andrés. Departamento de Economía; Argentina.Fil: Scartascini, Carlos. Universidad de San Andrés. Departamento de Economía; Argentina.Fil: Tommasi, Mariano. Universidad de San Andrés. Departamento de Economía; Argentina.Countries with different levels of state capacity have access to different sets of policies. In particular, countries with strong state capabilities are able to draw from a broader menu of policies, and pick and successfully implement those policies that best suit the nature of their challenges. In the case of exposure to trade related risk, the literature has usually considered that only one type of policies –those increasing government size- can help to overcome the challenge. However, there are a number of policies that can mitigate trade-induced risks, many of which do not have the necessary implication of increasing public spending. Yet, many such policies require governmental capabilities not available to any country. For that reason, the relationship between openness and the size of government might be mediated by the capabilities of states. The empirical analysis in this paper shows exactly that

Transición epitelio-mesenquimática (TEM): Principios e impacto clínico en la terapia contra el cáncer

The epithelial-mesenchymal transition (EMT) is a biological phenomenon responsible for the formation of different tissues and organs during normal metazoan development. Because of the connection of the EMT with the pathogenesis of certain diseases, such as cancer, the attention of the scientific community has been directed towards the search for and identification of effective therapeutic targets. These targets include signal transduction in cancerous stem cells and the use of microRNAs, which would inhibit EMT-associated phenotypic changes and tumoral progression. In an attempt to compile relevant and current information, this work addresses concepts that define the EMT and the advances in this field. The wealth of knowledge gained from areas such as the loss of cell polarity and intracellular adhesion complexes, the signaling pathways implicated, microRNA participation in this process, and stemness acquisition in embryonic and cancerous cells, all of which allow for the visualization of promising perspectives, particularly, methods for targeting advanced malignancies, are presented herein

Theodor Kocher: un cirujano innovador

Emil Theodor Kocher is considered along with Frank Lahey, Theodor Billroth, William Halsted, Charles Mayo, George Crile and Thomas Dunhill as one of the «Magnificent Seven», referring to the group of surgeons who managed thyroidectomy to make it a safe and efficient intervention that it is now practiced throughout the world. He was author of numerous contributions towards medicine. One of his most important contributions was to elucidate the function of the thyroid gland, through the observation and study of thyroidectomyzed patients, for which he was recognized by the academic and scientific community during the early twentieth century. Theodor Emil Kocher es considerado junto con Frank Lahey, Theodor Billroth, William Halsted, Charles Mayo, George Crile y Thomas Dunhill como uno de los llamados «Siete Magníficos» en alusión al grupo de cirujanos que lograron hacer de la tiroidectomía la intervención eficiente y segura que en la actualidad se practica en el mundo entero. Autor de innumerables aportes al arte de la medicina, quizás su contribución más importante fue haber dilucidado la función de la glándula tiroides, por medio de la observación y del estudio del estado de sus pacientes tiroidectomizados, hallazgo que le hizo acreedor del reconocimiento de la comunidad académica y científica de los comienzos del siglo XX

Transición epitelio-mesenquimática (TEM): Principios e impacto clínico en la terapia contra el cáncer

The epithelial-mesenchymal transition (EMT) is a biological phenomenon responsible for the formation of different tissues and organs during normal metazoan development. Because of the connection of the EMT with the pathogenesis of certain diseases, such as cancer, the attention of the scientific community has been directed towards the search for and identification of effective therapeutic targets. These targets include signal transduction in cancerous stem cells and the use of microRNAs, which would inhibit EMT-associated phenotypic changes and tumoral progression. In an attempt to compile relevant and current information, this work addresses concepts that define the EMT and the advances in this field. The wealth of knowledge gained from areas such as the loss of cell polarity and intracellular adhesion complexes, the signaling pathways implicated, microRNA participation in this process, and stemness acquisition in embryonic and cancerous cells, all of which allow for the visualization of promising perspectives, particularly, methods for targeting advanced malignancies, are presented herein

Pigment epithelium-derived factor: Clinical significance in estrogen-dependent tissues and its potential in cancer therapy

Pigment epithelium-derived factor (PEDF) is a glycoprotein that belongs to the family of noninhibitory serpins. The broad spectrum of PEDF biological activity is evident when considering its effects in promoting cell survival and proliferation, as well as its antiangiogenic, antitumor, and antimetastatic properties. Although the structural domains of the PEDF gene that mediate such diverse effects and their mechanisms of action have not been completely elucidated, there is a large body of evidence describing their diverse range of activities; this evidence combined with the regulation of PEDF expression by sex steroids and their receptors have led to the idea that PEDF is not only a diagnostic and prognostic marker for certain diseases such as cancer, but is also a potential therapeutic target. In this manner, this paper aims to generally review the regulation of PEDF expression and PEDF interactions, as well as the findings that relate PEDF to the role of estrogens and estrogen receptors. In addition, this manuscript will review major advances toward potential therapeutic applications of PEDF. © 2015, Mashhad University of Medical Sciences. All rights reserved

Pigment epithelium-derived factor: Clinical significance in estrogen-dependent tissues and its potential in cancer therapy

Pigment epithelium-derived factor (PEDF) is a glycoprotein that belongs to the family of noninhibitory serpins. The broad spectrum of PEDF biological activity is evident when considering its effects in promoting cell survival and proliferation, as well as its antiangiogenic, antitumor, and antimetastatic properties. Although the structural domains of the PEDF gene that mediate such diverse effects and their mechanisms of action have not been completely elucidated, there is a large body of evidence describing their diverse range of activities; this evidence combined with the regulation of PEDF expression by sex steroids and their receptors have led to the idea that PEDF is not only a diagnostic and prognostic marker for certain diseases such as cancer, but is also a potential therapeutic target. In this manner, this paper aims to generally review the regulation of PEDF expression and PEDF interactions, as well as the findings that relate PEDF to the role of estrogens and estrogen receptors. In addition, this manuscript will review major advances toward potential therapeutic applications of PEDF. © 2015, Mashhad University of Medical Sciences. All rights reserved