Estructuras de comunicación en el campo de la ciencia social en Chile : un Análisis de Redes

El objetivo de este artículo es analizar las redes existentes en el campo de la ciencia social en Chile y la incidencia de diversos factores sociocognitivos sobre la configuración estructural de tales redes. Para ello, analizo publicaciones que reportan resultados de investigación, tomando como base empírica las redes de citas y las redes de coautoría. Tal estudio lo hago con respecto a tres disciplinas: sociología, ciencia política y antropología, para el período 2000-2006, analizando 21.787 referencias. Los resultados muestran que las redes de comunicación científico social en el país son poco densas, con muy baja interdependencia y reciprocidad, baja conglomeración, y forma predominantemente jerárquica. En contradicción a la generalizada valoración de la interdisciplinariedad, se constata que las disciplinas ponen fuertes barreras a la comunicación. Los encuadramientos paradigmáticos, por su parte, aunque son fuertes atractores de conglomeración, son mucho menos excluyentes y existe un grupo reducido de investigadores que operan como mediadores interparadigmáticos. La investigación reveló además un significativo rol del género en la constitución de las redes. El análisis de redes permite, así, develar un conjunto de pautas de estructuración del campo de las ciencias sociales y contribuye a comprender su forma de operación.The purpose of this article is to analyze the existing networks in the field of social science in Chile and the incidence of diverse sociocognitive factors on the structural configuration of such networks. With that aim, I study publications that report research results, taking as empirical basis the network established through citations and the networks of coautorship. I made such study with respect to three disciplines: sociology, political science and anthropology, for the period 2000-2006, analyzing 21,787 references. The results show that the social scientific communications networks in the country are scarcely dense, with very low interdependence and reciprocity, and with low conglomeration, assuming a predominantly hierarchic form. In contradiction with the generalized valuation of interdisciplinarity, it is acknowledged that disciplines put strong barriers to the communication. The paradigmatic frameworks, on the other hand, although are strong atractors of conglomeration, they are much less excluding and exists a reduced group of investigators who operate like interparadigmatics brokers. The investigation revealed in addition a significant role of gender in the constitution of networks. The analysis of networks allows, thus, to reveal a set of patterns structuring the field of social sciences and contributes to understand its form of operation

An Analysis of Next Generation Access Networks Deployment in rural areas

Next generation access networks (NGAN) will support a renewed electronic communication market where main opportunities lie in the provision of ubiquitous broadband connectivity, applications and content. From their deployment it is expected a wealth of innovations. Within this framework, the project reviews the variety of NGAN deployment options available for rural environments, derives a simple method for approximate cost calculations, and then discusses and compares the results obtained. Data for Spain are used for practical calculations, but the model is applicable with minor modifications to most of the rural areas of European countries. The final part of the paper is devoted to review the techno-economic implications of a network deployment in a rural environment as well as the adequacy and possible developments of the regulatory framework involve

The mobile communications role in next generation networks: The case of Spain

Next generation access networks (NGAN) will support a renewed electronic communication market where main opportunities lie in the provision of ubiquitous broadband connectivity, applications and content. From their deployment it is - much - expected a wealth of innovations. Within this framework this paper reviews the technical architecture of a mobile network as a candidate for a NGAN deployment, derives a simple method for approcimate cost calculations, and then discusses the results obtained. Data for Spain are used for practical calculations, but the model is applicable with minor modivications to most ot the EU countries. The final part of the paper is devoted to reflect on the technical and economic feasibility of mobile communications as part of NGAN, as well as the adequacy and possible development of the current regulatory framework. --LTE,4G,Mobile communications,Next Generation Networks,Spain

High resolution system for nanoparticles hyperthermia efficiency evaluation

A system to evaluate nanoparticles efficiency in hyperthermia applications is presented. The method allows a direct measurement of the power dissipated by the nanoparticles through the determination of the first harmonic component of the in quadrature magnetic moment induced by the applied field. The magnetic moment is measured by using an induction method. To avoid errors and reduce the noise signal a double in phase demodulation technique is used. To test the system viability we have measured nanowires, nanoparticles and copper samples of different volumes to prove by comparing experimental and modeled result

El campo de las ciencias sociales en Chile: ¿Convergencia disciplinar en la construcción del objeto de estudio?

El artículo presenta los resultados de una investigación empírica que busca caracterizar el campo de las ciencias sociales en Chile, en el período 2000-2006, en cuanto a su proceso cognitivo, comparando entre las disciplinas. Para ello se constituyó un corpus de 479 publicaciones en las cuales se reportan investigaciones cuyos autores son sociólogos, cientistas políticos y antropólogos. Se analizó la forma en que, en tales investigaciones, se construyen los hechos científicos, en cuanto a encuadramiento paradigmático, construcción teórico conceptual y procedimientos metodológicos

Lower Cardiac Vagal Tone in Non-Obese Healthy Men with Unfavorable Anthropometric Characteristics

OBJECTIVES: to determine if there are differences in cardiac vagal tone values in non-obese healthy, adult men with and without unfavorable anthropometric characteristics. INTRODUCTION: It is well established that obesity reduces cardiac vagal tone. However, it remains unknown if decreases in cardiac vagal tone can be observed early in non-obese healthy, adult men presenting unfavorable anthropometric characteristics. METHODS: Among 1688 individuals assessed between 2004 and 2008, we selected 118 non-obese (BMI <30 kg/m²), healthy men (no known disease conditions or regular use of relevant medications), aged between 20 and 77 years old (42 ± 12-years-old). Their evaluation included clinical examination, anthropometric assessment (body height and weight, sum of six skinfolds, waist circumference and somatotype), a 4-second exercise test to estimate cardiac vagal tone and a maximal cardiopulmonary exercise test to exclude individuals with myocardial ischemia. The same physician performed all procedures. RESULTS: A lower cardiac vagal tone was found for the individuals in the higher quintiles - unfavorable anthropometric characteristics - of BMI (p=0.005), sum of six skinfolds (p=0.037) and waist circumference (p<0.001). In addition, the more endomorphic individuals also presented a lower cardiac vagal tone (p=0.023), while an ectomorphic build was related to higher cardiac vagal tone values as estimated by the 4-second exercise test (r=0.23; p=0.017). CONCLUSIONS: Non-obese and healthy adult men with unfavorable anthropometric characteristics tend to present lower cardiac vagal tone levels. Early identification of this trend by simple protocols that are non-invasive and risk-free, using select anthropometric characteristics, may be clinically useful in a global strategy to prevent cardiovascular disease

A tight MIP formulation of the unit commitment problem with start-up and shut-down constraints

This paper provides the convex hull description of the single thermal Unit Commitment (UC) problem with the following basic operating constraints: (1) generation limits, (2) start-up and shut-down capabilities, and (3) minimum up and down times. The proposed constraints can be used as the core of any unit commitment formulation to strengthen the lower bound in enumerative approaches. We provide evidence that dramatic improvements in computational time are obtained by solving the self-UC problem and the network-constrained UC problem with the new inequalities for different case studies