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Search Results: 1 - 10 of 200923 matches for " álvaro Cerón Beltrán "
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Inventario de contaminación emitida a suelo, agua y aire en 14 municipios del estado de Hidalgo, México
René Bernardo Elías Cabrera Cruz,Alberto José Gordillo Martínez,álvaro Cerón Beltrán
Revista internacional de contaminación ambiental , 2003,
Abstract: En el presente trabajo se realizó el inventario de las fuentes de contaminación en 14 municipios del estado de Hidalgo, México. Es importante determinar cualitativa y cuantitativamente las emisiones contaminantes en esta parte del estado que concentra alrededor de 40 % de la población, las principales vías de comunicación, los servicios y parques industriales. La metodología empleada está basada en la técnica de evaluación rápida de fuentes de contaminación ambiental. Esta técnica permite evaluar de manera rápida y económica las principales fuentes y zonas de contaminación; se utilizaron coeficientes y cálculos de aportes contaminantes basados en datos de producción industrial e información estadística. Se determinó el número de fuentes contaminadoras, su naturaleza y la cantidad de las emisiones a suelo, agua y aire en el área de estudio. Los resultados se agrupan de acuerdo con la clase de fuentes de contaminación por municipio, sector generador y tipo de contaminantes, esto permite la jerarquización de la problemática ambiental de Hidalgo y proporciona elementos para formular políticas de combate y prevención de la contaminación al ambiente en esta entidad.
Inventario de residuos peligrosos industriales en 17 municipios del Estado de Hidalgo, México
René Bernardo Elías Cabrera Cruz,Alberto José Gordillo Martínez,álvaro Cerón Beltrán
Revista internacional de contaminación ambiental , 2004,
Abstract: El objetivo del presente trabajo consistió en la realización de un inventario de residuos peligrosos en 17 municipios del estado de Hidalgo, México. Los resultados obtenidos son los primeros en su tipo y cumplen con el propósito fundamental de complementar y precisar la información sobre este tema; además, permitirán la formulación de acciones tales como programas de control y monitoreo de emisiones de residuos peligrosos, transporte adecuado, tratamiento y disposición final, tendientes a la mejora de la situación del ambiente en Hidalgo. La zona de estudio corresponde al 12.5% de la superficie total del estado y al 40.5% de su población; además concentra a todos los parques industriales y a las industrias más representativas de esta entidad. La metodología utilizada fue la Evaluación Rápida de Fuentes de Contaminación Ambiental. El estudio permitió identificar a las fuentes emisoras de residuos peligrosos y determinar sus clases, tipos y cantidades.
Variables influyentes en el rendimiento académico de los estudiantes
álvaro Muelas,Jesús, A. Beltrán
Revista de Psicología y Educación , 2011,
Abstract: El objetivo de este estudio fue doble: conocer la influencia de tres variables: inteligencia, estrategias de aprendizaje y personalidad sobre el rendimiento académico, y comprobar el descenso del rendimiento académico de los alumnos cuando pasan de la ESO al Bachillerato. 1.100 estudiantes de la Comunidad de Madrid incidentalmente seleccionados participaron en el estudio. Los resultados muestran que mientras la inteligencia y las estrategias de aprendizaje correlacionan positivamente con el rendimiento, la personalidad correlaciona negativamente. Asimismo, se confirma el descenso del rendimiento de los estudiantes cuando pasan de la ESO al Bachillerato.
ESTRUCTURA DE UNA COMUNIDAD DE LíQUENES Y MORFOLOGIA DEL GéNERO Sticta(STICTACEAE) EN UN GRADIENTE ALTITUDINAL
PéREZ QUINTERO,áLVARO LUíS; WATTEIJNE CERóN,BENICIA;
Acta Biológica Colombiana , 2009,
Abstract: lichen?s growth and distribution are conditioned by various environemental factors, altitude being an important one. in the cordillera oriental of colombian andes, there haven?t been studies on lichen?s altitudinal zonation. we studied the variation on lichen community structure along an altitudinal gradient (2000- 2600 m) in pnn tatamá, we found diversity diminishes as altitude increases, this being a variation from what?s generally found in lichen community behavior. at low altitudes, the community was conformed by fruticose lichens (30% cover at 2070 m and 0% at 2560 m), and by foliose lichens at high altitudes (15% cover at 2070 m and 43% at 2560 m). altitude, besides influencing lichen?s community structure, may affect their development and morphology. in the foliose genus sticta we found intraspecific variation on cyphellae (gaseous exchange organs) density associated with altitude, a significant effect of altitude on cyphellae density was found for the species s. andensis and s. gyalocarpa (anova p value= 0.008 and 0.05 respectively). this shows an adaptation mechanism of these organisms to the environmental changes given with altitude.
Estructura territorial del turismo en Guatemala
Sánchez Crispín, álvaro;Mollinedo Beltrán, Gerardo;Propin Frejomil, Enrique;
Investigaciones geográficas , 2012,
Abstract: the aim of this paper is to reveal the nuclei, flows and surfaces generated by tourism in guatemala that, nowadays, constitute the basis for the promotion of the country in the international market. following the trend in central america, and after a long civil war, guatemala is encouraging the growth of its tourism economy. the starting point of this research is rooted in the fact that there are only a handful of places, distributed over the guatemalan territory, that articulate the tourist flows (constituted mainly by international visitors) and onto which tourism surfaces are being constructed. we assume that this territorial structure is still weak, does not include all areas of the country and it is mostly dependant on regional emitting markets. the context of the territorial structure of tourism in guatemala suggests that all countries in the region are competing to get access to the international tourism market and that this competition will be decided in favour of those nations that mastermind the administration of their natural and cultural resources. at the end of the text, we comment on the basics of the territorial structure found by our study.
Factores genéticos y ambientales asociados con la respuesta a warfarina en pacientes colombianos
Isaza,Carlos; Beltrán,Leonardo; Henao,Julieta; Porras,Gloria; Pinzón,Alfredo; Vallejos,álvaro; Machado,Jorge;
Biomédica , 2010,
Abstract: introduction.warfarin is an anticoagulant that is difficult to administer because of its narrow therapeutic margin and the numerous factors that influence patient response. objective. demographic, clinical and genetic variables were characterized to establish the appropriate maintenance dosages of warfarin. materials and methods. the colombian patients consisted of 145 adults of both sexes. they were in stable anticoagulation status with international normalized ratio between 2 and 3 for at least two months, and without changes in the warfarin commercial preparation or in the dosage. after signing the informed consent, the following data was recorded for each volunteer: age, gender, weight, height, smoker status, co-morbidity, co-medication, international normalized ratio (inr), warfarin dose, and commercial brand. each patient was typed for genes cyp2c9, vkorc1, cyp4f2 and proc; for 59 patients, the serum levels of warfarin were quantified. the genotyping and the blood quantification were performed by mini-sequencing and hplc methods, respectively. results. age, co-medication with enzymatic inhibitors (amiodarone, sertraline, fluoxetine) or inducers (phenytoin, carbamazepine), and the alleles rs1799853 (*2) and rs1057910 (*3) of the cyp2c9 gene, as well as rs9923231 of the vkorc1 gene were associated with warfarin dose required to achieve anticoagulation with inr of 2-3. these variables were included in a multiple linear regression model for predicting the optimum dose/week of warfarin. this resulted in an algorithm that explained 47.4% of the variability in the dose responses. conclusion: clinical and pharmacogenetic variables provided a basis for improving the safety and effective dosage of warfarin; however, the use of a pharmacogenetic algorithm will require patient data obtained during clinical trials.
Análisis curricular del bachillerato general por competencias de la Universidad de Guadalajara: Un enfoque desde la teoría de redes
Torres Nabel,Luis César; Beltrán Ibarra,álvaro; Martínez Favela,Francia Carmen; Aguayo álvarez,Zeferino;
Investigación y Postgrado , 2009,
Abstract: this research reveals a curricular study of a general highschool program per skills (hps) developed in the universidad de guadalajara. the analysis was made with theoretical postulates and methodological tools that the network theory offers. the basic idea was to compress the original curricular map of hps from three years to two, in non-conventional modalities. the results of the analysis allowed to condense 44 units of learning in 20 units, divided in 7 areas (comprehension of the human being and citizenship a and b, communication a and b, mathematical thinking, comprehension of nature, formation for welfare), once reestablished in the curricular reform of the hps. the integration was raised through the use of rates familiarized with network analysis, which allowed determining the affinity between the learning units to integrate them. this study provided some parameters for a better understanding of the interdiscipleness.
Air Pollution in the Gulf of Mexico  [PDF]
Manuel Muriel-García, Rosa María Cerón-Bretón, Julia G. Cerón-Bretón
Open Journal of Ecology (OJE) , 2016, DOI: 10.4236/oje.2016.61004
Abstract: An integral analysis of Air Pollution in the Gulf of Mexico was made considering pollutants emissions assessment and diagnosis; air pollution monitoring; and modeling of air pollution dispersion. Combustion sources considered in this work were: thermoelectric power plants and open flares; and pollutants considered were sulfur dioxide, nitrogen dioxides, particulate matter (PM10 and PM2.5), Total suspended particles (TSP) and carbon monoxide (CO). This study made evident a lack of more recent information and a homogenization in emissions factors in order to know the conditions of air pollution in the Gulf of Mexico in a more reliable way.
Potential Effects on Human Health of Hydrogen Sulfide Exposure in a Place in Southeast of Mexico  [PDF]
Manuel Muriel-García, Rosa María Cerón-Bretón, Julia Griselda Cerón-Bretón
Open Journal of Ecology (OJE) , 2016, DOI: 10.4236/oje.2016.61005
Abstract: Ambient concentrations of H2S were determined by modeling the H2S emissions dispersion for three sites located in the surroundings of oil and gas maritime terminal at the southeast of Mexico. Hazard quotient is reported for different age groups. Paraiso City in Tabasco State reported the highest values for over 19 years old group (0.49). It was concluded that there was no threat to human health due to H2S emissions derived from the maritime terminal for the studied sites.
Nosotros y otros en manuales escolares de geografía de Colombia (1970-1990)
Cerón Rengifo,Patricia;
Folios , 2012,
Abstract: abstract in order to examine the identification of population in social studies school textbooks, a study was conducted about the constructions of the terms us and others in a sample of geography of colombia school textbooks, intended to be used in secondary school level, published between 1970 and 1990. methodological tools proposed by van dijk (2008) and wodak (2003) were used in order to study the ideological identity discourse of social groups, based on the tracking of the positive representation of us and the negative representation of others. a promotion of a culturally homogeneous national identity and a hierarchized classification of the population were found. this was done through categories based on the idea of race, social status and territory. the government and the elites composed of urban, affluent white people who live in the high plateau of the departments of cundinamarca and boyacá appear to be the us and are represented in a positive way, while the population categorized as peasant, villager, indian, black, mulatto or zambo is included in the term others and is represented negatively.
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