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Origin Parameters of Fused Flux Grain Process Dispersion with Air Parámetros de origen del proceso de dispersión con aire de fundentes fundidos
Daniel Pérez Pérez,Carlos René Gómez Pérez,Francisco Arturo Ruiz Martínez,Eriel Pérez Zapico
Revista Cubana de Ingeniería , 2011, DOI: 10.1234/rci.v2i1.39
Abstract: Considerations about the fragmentation process with air of molten fluxes obtained by using raw Cuban materials for the welding process under submerged arch (S.A.W) are presented. The physical process of the flight trajectory and its validation during the granulation with air are not reported in the welding field. Therefore, the aim of this work is to establish a procedure that determines the rates and departure angles of pellets during impulsion and dispersion, in addition to contribute criteria on the frictional effect of the surrounding atmosphere on the shape of the trajectory curve of the pellets formed. These aspects may be corroborated with data obtained from the digital processing of filmed images of the fragmentation process and movement of the pellets formed. It is demonstrated that the efficiency of the procedure developed for the obtaining of the flight parameters and the non-influence of the air frictional force on the modification of the particle’s flight trajectory, allows the establishment of a methodology that makes it possible to begin studies about the fragmentation phenomena of molten fluxes by using air jets, which guarantee the necessary rank and granulometric types for an adequate performance of the welding process. Se plantean consideraciones sobre el proceso de fragmentación con aire de fundentes fundidos, obtenidos utilizando materias primas cubanas, para el proceso de soldadura bajo arco sumergido (SAW). El proceso físico de la trayectoria de vuelo y su validación durante la granulación con aire no se reportan en el campo de la soldadura. El objetivo de este trabajo es establecer un procedimiento para determinar las velocidades y ángulos de salida de los peles durante su impulsión y dispersión, además de aportar criterios del efecto friccional de la atmósfera circundante sobre la forma de la curva de trayectoria de los peles formados. Estos aspectos se pueden corroborar con los datos obtenidos mediante el procesamiento digital de las imágenes filmadas del proceso de fragmentación y desplazamiento de los peles formados. Se demuestran la eficacia del procedimiento desarrollado para la obtención de los parámetros de vuelo y la no influencia de la fuerza friccional del aire sobre la modificación de la trayectoria de vuelo de las partículas, permitiendo establecer una metodología, que posibilita iniciar estudios sobre los fenómenos de fragmentación de fundentes fundidos empleando chorros de aire, que garanticen los rangos y clases granulométricas necesarias para un adecuado desempe o del proceso de soldadura.
Study of Fragmentation Process of Fused Fluxes Using Air Estudio del proceso de fragmentación de fundentes fundidos usando aire
Daniel Pérez Pérez,Carlos René Gómez Pérez,Francisco Arturo Ruiz Martínez,Jorge Víctor Miguel Oria
Revista Cubana de Ingeniería , 2011, DOI: 10.1234/rci.v2i2.47
Abstract: In the paper the fragmentation process with air of fused fluxes is studied by means of a particular treatment of the interaction process between the air and flux fluids starting from physical and mathematical considerations of the collision phenomenon which are the result of the application of Newton's mechanics-classical theory. In the paper is schematized the impact and change of trajectory process of the incandescent fused flux flow because of the air mechanical action provided by a blowpipe and the equations referred to the interaction between the fluids are set. As a result, the equations for estimating the exit angle and the average velocities of the pellets formed are determined whenever the interacting air and flux fluxes are known as well as the incidence angles. From the theory developed the essential parameters of the granulation process with air of fused fluxes, by considering the average diameter of the particles to be obtained for their industrial performance can be estimated. En el trabajo se estudia el proceso de fragmentación con aire de fundentes fundidos, a través de un tratamiento particular del proceso de interacción entre los fluidos de aire y de fundente, a partir de las consideraciones físicas y matemáticas del fenómeno de los choques que son resultado de la aplicación de la teoría mecano-clásica de Newton. Se esquematiza el proceso de impacto y cambio de trayectoria del chorro de fundente fundido incandescente por la acción mecánica del aire, suministrada por un soplador, y se plantean las ecuaciones referentes a la interacción entre los fluidos. Como resultado se determinan las ecuaciones para estimar el ángulo de salida y las velocidades promedio de los peles formados, si se conocen los flujos de fundente y de aire interactuantes, así como los ángulos de incidencia. A partir de la teoría desarrollada pueden estimarse los parámetros esenciales del proceso de granulación con aire de fundentes fundidos, considerando el diámetro medio de partículas a obtener para su ejecución industrial.
Social Profiles and Social Behaviour and Attitudes towards Gaming and On-Line Gaming in Spain
Francisco Javier RUIZ MARTíNEZ
Economia : Seria Management , 2011,
Abstract: For the last two decades our world has experienced increasing globalization linked to the revolution in Information and Communication Technologies (ICT) leading to new business spheres escaping from the traditional Nation-State control. The gaming business is one of these areas and has recorded a notable increase in profits in the last decade: gambling, betting and network games constitute some of the main issues developed by ICT companies located beyond State control. The action of the States is focusing on the formulation of new public policies that allow them to control these activities. But first a deep social description of gaming is needed to know which actors are involved in this field of activities, which is the profile of the gamer and what kind of social attitudes are carried out by users and companies taking part of the business. This article focuses on the social profiles and the social behaviour and attitudes towards gaming in Spain, and specially in the transition from traditional gaming to on line gaming.
El Servicio Electoral Profesional en el Estado de México: un recuento de las implicaciones electorales 2003-2006
Francisco Martínez Martínez,Arturo Antonio González Torices
Espacios Públicos , 2008,
Abstract: La concepción, organización y desarrollo de elecciones son un aspecto de la vida democrática de los Estados modernos, actualmente son determinantes para el correcto ejercicio del poder y de la autoridad pública, por tanto su afección va más allá del simple ejercicio e instrumento del voto; por tal motivo, la integración de la estructura electoral y, particularmente la del Estado de México, reviste interés desde que, a partir del mismo se sustenta una buena parte de la consolidación de las instituciones que, emanadas de tal ejercicio, concite a las mejores prácticas en la vida cotidiana de los habitantes de su territorio, en tal sentido un adecuado sistema de integración e incorporación de servidores electorales prevendría y mejoraría la relación de distanciamiento entre ciudadano y autoridades electorales y, en sentido más amplio, daría confianza y certidumbre a los resultado obtenidos.
Earliest Known Use of Marine Resources by Neanderthals
Miguel Cortés-Sánchez, Arturo Morales-Mu?iz, María D. Simón-Vallejo, María C. Lozano-Francisco, José L. Vera-Peláez, Clive Finlayson, Joaquín Rodríguez-Vidal, Antonio Delgado-Huertas, Francisco J. Jiménez-Espejo, Francisca Martínez-Ruiz, M. Aranzazu Martínez-Aguirre, Arturo J. Pascual-Granged, M. Mercè Bergadà-Zapata, Juan F. Gibaja-Bao, José A. Riquelme-Cantal, J. Antonio López-Sáez, Marta Rodrigo-Gámiz, Saburo Sakai, Saiko Sugisaki, Geraldine Finlayson, Darren A. Fa, Nuno F. Bicho
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0024026
Abstract: Numerous studies along the northern Mediterranean borderland have documented the use of shellfish by Neanderthals but none of these finds are prior to Marine Isotopic Stage 3 (MIS 3). In this paper we present evidence that gathering and consumption of mollusks can now be traced back to the lowest level of the archaeological sequence at Bajondillo Cave (Málaga, Spain), dated during the MIS 6. The paper describes the taxonomical and taphonomical features of the mollusk assemblages from this level Bj19 and briefly touches upon those retrieved in levels Bj18 (MIS 5) and Bj17 (MIS 4), evidencing a continuity of the shellfishing activity that reaches to MIS 3. This evidence is substantiated on 29 datings through radiocarbon, thermoluminescence and U series methods. Obtained dates and paleoenvironmental records from the cave include isotopic, pollen, lithostratigraphic and sedimentological analyses and they are fully coherent with paleoclimate conditions expected for the different stages. We conclude that described use of shellfish resources by Neanderthals (H. neanderthalensis) in Southern Spain started ~150 ka and were almost contemporaneous to Pinnacle Point (South Africa), when shellfishing is first documented in archaic modern humans.
Un modelo macroeconométrico de simulación con microfundamentos para la economía mexicana
Lucía A. Ruiz Galindo,Francisco Venegas Martínez
Economía Mexicana , 2007,
Abstract: En este trabajo se desarrolla un modelo macroeconométrico de simulación para México con base en microfundamentos. Esta propuesta tiene varias características que la distinguen de otros modelos que se han elaborado previamente para la economía mexicana. Las relaciones de comportamiento no son formuladas ad-hoc, sino son el resultado del estudio de la conducta racional de todos los agentes económicos y de su interacción con los mercados. A través del planteamiento de modelos de decisión intertemporal, se determina la dinámica de las variables macroeconómicas relevantes. El modelo permite reproducir hechos estilizados de la economía mexicana durante el periodo de 1995 al 2002.
Geochemical Prospection of the Chapala Ciénega at Michoacán State  [PDF]
José Martínez Reyes, Ivan Vera Romero, Meliton Estrada Jaramillo, Agustina Ortiz Soriano, Ignacio Moreno Nava, Francisco Gabriel Montes Ayala, Francisco García ávalos, Ernesto Mendez Ruiz
International Journal of Geosciences (IJG) , 2014, DOI: 10.4236/ijg.2014.59086
Abstract:

The geochemical prospection as a branch of Applied Geochemistry or “Geochemistry of the Landscape” studies the spatial and temporal location of geochemical anomalies in order to locate geological resources of economic value. The Ciénega de Chapala zone in Michoacán is located east of the Citala rift hosting a geological system that leads to regional hydrothermal activity, mainly the Pajacuaran and Ixtlan failures. The regional geothermics include a superficial hydrothermalism consisting of springs and wells of hot water with temperatures between 48°C and 94°C in Ixtlan de los Hervores and mud volcanoes in the water with temperatures between 48°C and 94°C in Ixtlan de los Hervores and mud volcanoes in the Los Negritos. The waters and gases of these hydrothermal manifestations have physicochemical characteristics that indicate the presence of geothermal fluids. To search for possible presence of minerals of economic value, a study of elemental chemical analysis was performed by scanning electron microscopy in samples of rock of the sierra de Pajacuaran, the result of the analysis is clearly abnormal values which may be indicative a geochemical anomaly as well as the possible presence of minerals of economic value in the region. Given the above, the area of the Ciénega de Chapala in Michoacán is a zone where work can be continued both geothermal and mineralogical exploration by conventional techniques or even totally innovative technologies.

Could Low Hdl-Cholesterol Levels Be an Unvalued Predictor of Cancer Risk?: A Retrospective Case Study  [PDF]
Juan Antonio Vílchez, Natalia Sancho-Rodríguez, Ana Martínez-Ruiz, Enrique Martínez-Sánchez, Francisco Ruiz-Espejo, Isabel Tovar-Zapata, Jose Antonio Noguera-Velasco
International Journal of Clinical Medicine (IJCM) , 2015, DOI: 10.4236/ijcm.2015.612129
Abstract: Background: The relationship between serum lipid profile levels and cancer risk remained uncertain. Recently, it had been reported a significant inverse association between high-density lipoprotein cholesterol (HDL) and the risk of incident cancer that was independent of low-density lipoprotein cholesterol (LDL), age or sex. Objective: The aim of our study was to evaluate the behavior of HDL in cancer patients and in healthy population. Methods: We created a retrospectively search strategy in the laboratory information system (LIS). We filtered and searched those patients with CEA within 5 - 20 ng/ml and any value of HDL and corroborated the presence of cancer (Group 1 (G1)) or not (Group 2 (G2)). Moreover, we searched a control group (patients in outpatient oncology clinic) to observe the values of HDL. Comparisons and statistical logistic regression models were applied to link the levels of this biomarkers and cancer risk. Results: We examined 852 valid patients, median age 62 (50 - 73) years. Within the search strategy group, G2 showed highest levels of HDL (54 (43 - 67) mg/dl) and lowest CEA levels (6.7 (5.7 - 8.4) ng/ml) comparing with G1: HDL (47 (37 - 60) mg/dl) and the CEA (7.9 (6.2 - 10.9) ng/ml); p < 0.001. The values in control group were: the lowest HDL levels (41 (29 - 54) mg/dl) and CEA (25.2 (6.1 - 124.5) ng/ml); p < 0.001, between oncologic patients and the search strategy group. On logistic regression multivariate analysis, we obtained: r2: 0.092; p < 0.001; HDL [OR: 0.983 (0.974 - 0.993), (p = 0.001)] and CEA [OR: 1.115 (1.060 - 1.174), (p < 0.001)] and they were confirmed as independent predictors of cancer. Conclusion: Our findings confirmed the inverse association of HDL levels between healthy populations and were diagnosed with cancer. Moreover, in a random population, patients with cancer presented lower HDL values compared to those without cancer. Therefore, it could demonstrate the possible positive predictive value of low HDL related to cancer risk.
Expectativas de migración internacional en estudiantes de enfermería en México, Distrito Federal
Rosales-Martínez,Yetzi; Nigenda,Gustavo; Galárraga,Omar; Ruiz-Larios,José Arturo;
Salud Pública de México , 2010, DOI: 10.1590/S0036-36342010000300009
Abstract: objective: to analyze the factors associated with the expectations to migrate abroad among nursing students in mexico city. material and methods: a cross-sectional study was conducted with a non-random sample of 420 students. a logistic regression model was estimated. results: a total of 69% of the informants expressed their intention to move abroad, to look for employment (65%) and/or to continue their studies (26%). of those, 50% would choose canada as their destination, followed by spain and the united states. the variables associated with migration expectations were: age, income, having relatives abroad, and perception of poor labor conditions and low wages in mexico. conclusions: results are consistent with international literature. low wages, poor labor conditions and the limited possibilities for professional development in mexico are factors that contribute to generate migration expectations among nursing students. additionally, optimistic perceptions about the job market and the labor demand in more developed countries heighten expectations to migrate.
Características ecocardiográficas da cardiomiopatia n?o-compactada: diagnóstico perdido ou err?neo
Martínez-Baca López, Francisco;Alonso Bravo, Rosa Marisol;Rodríguez Huerta, Domingo Arturo;
Arquivos Brasileiros de Cardiologia , 2009, DOI: 10.1590/S0066-782X2009000800024
Abstract: non-compaction cardiomyopathy is a rare disease, anatomically characterized by a prominent trabecular pattern and deep intertrabecular recesses. its clinical manifestations include severe left ventricular dysfunction, arrhythmias, systemic embolism, and sudden death. in this report, two cases of patients of different ages with non-compaction cardiomyopathy are described: a male schoolboy whose pathology was associated with mitral stenosis and regurgitation and a 50-year-old female with history of high blood pressure and cardiac failure.
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