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Search Results: 1 - 10 of 548427 matches for " Robinson A. Vázquez Ramos "
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Necesidades académicas, personales, sociales y vocacionales de estudiantes internacionales e intercambio en la Universidad de Puerto Rico, Recinto de Río Piedras / Academic, Personal, Social and Vocational Needs of International and Exchange Students at the University of Puerto Rico, Río Piedras Campus
ángel A Villafa?e Santiago,Carol Y Irizarry Robles,Robinson A Vázquez Ramos
Revista Electrónica Educare , 2011,
Abstract: Recibido 20 de setiembre de 2011 Aceptado 24 de octubre de 2011 Corregido 14 de noviembre de 2011 Resumen. El propósito de este estudio fue identificar las necesidades de una muestra de estudiantes internacionales y de intercambio que cursan estudios en la Universidad de Puerto Rico, Recinto de Río Piedras. Se exploraron datos socio-demográficos así como las necesidades académicas, vocacionales, y personales/sociales, con los fines de recopilar información de relevancia para universidades que sirven esta población y someter recomendaciones que atiendan las necesidades. Los hallazgos revelaron necesidades mayormente en las áreas académicas y vocacionales. Entre estas, se destacan la necesidad de aprender inglés o espa ol, y el conocer sobre internados y ofrecimientos académicos en Puerto Rico y fuera del país, sueldo y oportunidades de empleo, ayudas económicas y servicios estudiantiles en la Universidad de Puerto Rico. Se proveen recomendaciones para trabajar con las necesidades identificadas ya que, según establece la bibliografía, las dificultades que confrontan estos/as estudiantes pueden afectar su desempe o académico e incluso su salud emocional. Abstract. The purpose of this study was to identify the needs of a sample of the international and exchange students staying at the North Tower Residence of the University of Puerto Rico, Río Piedras Campus. Social and demographic data, as well as the academic, vocational, and social/personal needs were explored with the purpose of gathering relevant information and submitting recommendations to universities serving this student population. Findings revealed particular needs in the academic, vocational areas, including English or Spanish learning, information on internships and study programs in Puerto Rico or abroad, salary and employment opportunities, financial aid and services available to the students of this University. Recommendations are provided to work with the identified needs. According to the literature, difficulties faced by these students may affect their academic performance and emotional health.
Construction and validation of Experiences Questionnaire on Violence in Couple and Family Relations in University Students [Desarrollo del Cuestionario de Experiencias de Violencia en las Relaciones de Pareja y Familia en Estudiantes Universitarios]
Angel A. Villafa?e Santiago,Maria Isabel Jimenez Chafey,Damaris De Jesus Carrasquillo,Robinson A. Vázquez Ramos
Universitas Psychologica , 2012,
Abstract: This study describes the process of developing the Experiences of Violence in Couple and Family Relationships in University Students Questionnaire, its psychometric properties and the results of the pilot study. The research design used for this study was a nonexperimental, transversal co relational design. The nonrandomized sample consisted of 267 students. The final version of the questionnaire consisted of 41 items and four sub-scales which measured experiences with violence in a relationship as an Aggressor and as a Victim, Observed between the Parents and in the Parent-child relationship as a victim. The total scale and the subscales obtained adequate reliability indexes. On average, the sample reported ten experiences with violence in different contexts. The results of this study contribute data on the prevalence of violence in college students’ romantic and family relationships which in turn, provide valuable information for planning prevention and early intervention efforts with this population.
Estudio de los parámetros básicos del drenaje 20 de Noviembre de la NOM-002-ECOL-1996, en la ciudad H. Matamoros, Tamaulipas.
Vargas Ramos, C.,Cantú Ibarra, G.,Vargas Ramos, A.,Vázquez Galindo, L.
CONHISREMI , 2009,
Abstract: In H. Matamoros, Tamaulipas the waste waters and the rainwater are unloaded to open drainages and later sent to the sea. 71% of the total volume generated by the population unloading in drainage 20 de Noviembre and this drain system runs across the city from north to south with an approximate length of 12,1km. The importance of the study of this drainage is that it transports the greater amount of waste water of the city. The city of H. Matamoros, Tamaulipas does not have a treatment system for the wastewater generated locally. The wastewater and rainwater are discharged into open drainages and later drained to a nearby sea. The importance of analyzing the quality of the water in the drain system 20 de Noviembre is because it transports 71 % of the total volume that is generated. This drain system runs across the city from north to south with an approximate length of 12,1km.The analysis was performed according to the described methodology of the official Mexican standard NOM-002-ECOL-1996. As a point of reference on the situation of this body of water across the time, a bibliographical research was conducted by reviewing the files of the state department that is in charge of managing the wastewater and also previously studies done by the Technological Institute of Matamoros. Among the analyzed parameters, it was found that the amount of total suspended solids exceeds 17,3% the maximum permissible limit, and that the fats and oils exceed 17,3% the parameters established by the standard.
Influence of temperature, humidity and rainfall on field population trend of Stomoxys calcitrans (Diptera: Muscidae) in a semiarid climate in Mexico
CRUZ-VáZQUEZ,CARLOS; VITELA MENDOZA,IRENE; RAMOS PARRA,MIGUEL; GARCíA-VáZQUEZ,ZEFERINO;
Parasitología latinoamericana , 2004, DOI: 10.4067/S0717-77122004000300002
Abstract: the influence of temperature, humidity and rainfall on field population trend of stable fly, stomoxys calcitrans, over three consecutive years in two dairy farms located in semiarid climate in aguascalientes state, in mexico, were determined. the dairies were visited weekly between april 1999 to march 2002, on each occasion 10% of the dairy cows were selected making direct counts of stable flies observed front the legs. the occurrence of stable fly adults from weekly counts was divided in four population phases: population increasing phase i (first peak), fluctuation phase, population increasing phase ii (second peak) and population decreasing phase, for each year of study. pearson's correlation analysis was developed (p < 0.01) between weekly average fly number per cow and mean temperature, mean relative humidity and rainfall recorded from one to four weeks before count in each population phases. the population increasing phase i, was observed in spring-summer period, in where relative humidity had significant correlation indices (r = 0.6 to 0.8), the first peak occurred in september, june and august, of each year studied, respectively. the population-decreasing phase was observed between last weeks of summer and in the fall, showed high correlation indices with temperature (r = 0.9). no significant correlations were founded with the rainfall over the study.
Influence of temperature, humidity and rainfall on field population trend of Stomoxys calcitrans (Diptera: Muscidae) in a semiarid climate in Mexico
CARLOS CRUZ-VáZQUEZ,IRENE VITELA MENDOZA,MIGUEL RAMOS PARRA,ZEFERINO GARCíA-VáZQUEZ
Parasitología latinoamericana , 2004,
Abstract: The influence of temperature, humidity and rainfall on field population trend of stable fly, Stomoxys calcitrans, over three consecutive years in two dairy farms located in semiarid climate in Aguascalientes State, in Mexico, were determined. The dairies were visited weekly between April 1999 to March 2002, on each occasion 10% of the dairy cows were selected making direct counts of stable flies observed front the legs. The occurrence of stable fly adults from weekly counts was divided in four population phases: population increasing phase I (first peak), fluctuation phase, population increasing phase II (second peak) and population decreasing phase, for each year of study. Pearson's correlation analysis was developed (P < 0.01) between weekly average fly number per cow and mean temperature, mean relative humidity and rainfall recorded from one to four weeks before count in each population phases. The population increasing phase I, was observed in spring-summer period, in where relative humidity had significant correlation indices (r = 0.6 to 0.8), the first peak occurred in September, June and August, of each year studied, respectively. The population-decreasing phase was observed between last weeks of summer and in the fall, showed high correlation indices with temperature (r = 0.9). No significant correlations were founded with the rainfall over the study. El trabajo tuvo como objetivo determinar la influencia de la temperatura, humedad y la precipitación pluvial en la curva poblacional de campo de la mosca del establo, Stomoxys calcitrans, en un periodo de tres a os en dos establos lecheros localizados en un clima semiárido en el estado de Aguascalientes, México. Los establos se visitaron semanalmente entre abril de 1999 y marzo del 2002, en cada ocasión se seleccionó al 10% de las vacas en lactancia realizando un conteo directo de moscas del establo que se observaran en el frente de las piernas. La ocurrencia de la mosca del establo en los conteos semanales fue dividido en cuatro fases: incremento poblacional fase I (primer pico), fase de fluctuación, incremento poblacional fase II (segundo pico) y fase de decremento poblacional, para cada a o de estudio; se realizó un análisis de correlación de Pearson (P < 0,01) entre el promedio semanal de moscas por vaca y la temperatura promedio, humedad relativa promedio y precipitación pluvial registradas de una a cuatro semanas antes del conteo, en cada una de las fases poblacionales. En el incremento poblacional fase I (primavera-verano), la humedad relativa fue el único factor climático con índices de cor
Estimulación de la síntesis de ADN y de proteínas del ciclo celular por auxinas durante la germinación de maíz
Arellano, Yazmín;García, Elpidio;Vázquez-Ramos, Jorge M.;
Agrociencia , 2008,
Abstract: the establishment and progress of the cell cycle are important events for the germination of seeds. in maize the auxins and the exogeniously added cytokinins stimulate the synthesis of dna during the early hours of germination, and this effect depends, to a greater or lesser extent, on the presence of sucrose in the imbibition buffer. however, in the absence of exogeniously added hormones, the presence or absence of sucrose does not affect the synthesis of dna at early or late times of germination. therefore, the effect of the phytoregulators would be more related to the stimulation of a mitogenic action, than to the germinative process per se. when measuring the presence of specific proteins of the phases g1 and s of the cell cycle, in the presence of auxins, it was evident that markers of g1 such as the cyclins d2;1 and d4;1, or markers of the s phase such as cyclin a1 or pcna, did not change their levels during germination. besides, the levels of a marker of g1, the cyclin d5;2 and a marker of the s phase, the dna polymerase a, increased visibly in response to the addition of auxins. this response and in particular that of dna polymerase a, could explain the increase in the synthesis of dna caused by the addition of auxins in embryonic axes during germination.
Influencia de algunos factores climáticos en la distribución anual de la infestación por Haematobia irritans (Diptera:Muscidae) en un establo lechero de Aguascalientes, México
Carlos Cruz Vázquez,Miguel Ramos Parra,Zeferino García Vazquez,Catarino Perales Segovia
Veterinaria México , 2003,
Abstract: Se visitó semanalmente de marzo de 1999 a marzo de 2001 un establo que contaba con 510 vacas Holstein en producción y que no aplicó insecticidas durante el estudio. En cada ocasión se seleccionó 10% de las vacas en lactancia y se realizó un conteo directo del número de moscas Haematobia irritans observadas. Se calculó el número promedio semanal de moscas por vaca para identificar los periodos correspondientes al primer incremento poblacional, fluctuación, segundo incremento y decremento. Se realizó un análisis de correlación de Pearson (P < 0.01) entre el promedio semanal de moscas por vaca y temperatura, humedad relativa y precipitación pluvial, en cada uno de los periodos poblacionales. El nivel de infestación fue más alto cerca de los dos picos poblacionales, en verano-oto o, y nunca fue superior a 120 moscas por vaca. Durante el periodo de enero a marzo no se observaron moscas. En el primer incremento poblacional se encontraron altos índices de correlación, 0.80 y 0.85, para temperatura y 0.68 y 0.71 para humedad relativa, en cada a o de estudio. En el decremento se observaron altos índices de correlación con la temperatura, 0.79 y 0.80. No se detectó correlación significativa con la precipitación pluvial. La temperatura influyó considerablemente en la distribución anual de la infestación por H. irritans, promoviendo o limitando los periodos poblacionales identificados.
Chromatin Bound PCNA is Complexed with Cell Cycle Protein Regulators as Determined by Chromatin Immunoprecipitation
Nazul Becerril,Miguel ángel Martínez,Elpidio García,Jorge Manuel Vázquez Ramos
Revista de la Sociedad Química de México , 2012,
Abstract: Mediante inmunoprecipitación de la cromatina, hemos detectado la formación de complejos entre la proteína homotriméricaanular Antígeno Nuclear de Proliferación Celular, ANPC, y dos reguladores fundamentales del ciclo celular, CdkA y Ciclina D4;2 durantela germinación de maíz. Se sugiere la forma en que ANPC participaría en el control de la fase G1, al permitir al complejo ciclina-cinasa encontrar y fosforilar proteínas blanco. Incidentalmente, ANPC podría formar una estructura de dímero de trímero cuando se halla unida a la cromatina.
INTERACCIóN GENOTIPO-AMBIENTE DEL RENDIMIENTO Y CALIDAD DE GRANO Y TORTILLA DE HíBRIDOS DE MAíZ EN VALLES ALTOS DE TLAXCALA, MéXICO
María Gricelda Vázquez Carrillo,David Santiago Ramos,Yolanda Salinas Moreno,Israel Rojas Martínez
Revista fitotecnia mexicana , 2012,
Abstract: Actualmente la baja productividad del maíz (Zea mays L.) en los Valles Altos del Centro de México se debe a condiciones ambientales adversas de sequía, temperatura más alta que la usual y heladas tempranas. Para aumentar la productividad es necesario desarrollar variedades estables con rendimiento alto y que cumplan con las características físicas de grano, nixtamal y tortilla que demandan las industrias procesadoras. En este trabajo se determinó el efecto de la interacción genotipo x ambiente sobre el rendimiento, las características físicas del grano y la calidad de nixtamal y tortillade 20 híbridos pre-comerciales y comerciales de maíz cultivados durante el ciclo primavera-verano de 2009 en seis localidades de los Valles Altos de Tlaxcala, México. Se evaluó el rendimiento de grano, peso hectolítrico, peso de 100 granos (PCG), índice de flotación (IF), color de grano y harina, y la calidad de nixtamal y tortilla. Los resultados para rendimiento y características físicas del grano fueron analizados estadísticamente mediante el modelo de efectos principales aditivos e interacción multiplicativa (AMMI), y los de calidad de nixtamal y tortilla bajo un dise o completamente al azar. El modelo AMMI proporcionó buena descripción de la interacción genotipo x ambiente, y de la estabilidad de los 20 híbridos. Las condiciones de siembra y las ambientales modificaron las características físicas de los híbridos, especialmente el tama o del grano y la dureza. Huamantla y Tlatempa fueron las mejores localidades en rendimiento (9.8 y 8.3 t ha-1), tama o (PCG > 33 g), dureza (IF < 40 %) y calidad de tortilla. Nicolás Bravo, Emiliano Zapata y San Bartolomé Cuahuixmatlac fueron las localidades que más afectaron adversamente al rendimiento (3.8, 4.3, 2.6 t ha-1) y al tama o y dureza del grano (PCG < 33 g, IF > 60 %). De los híbridos evaluados 15 cumplieron con las especificaciones de la industria de la masa y tortilla, pero ninguno cumplió las especificaciones de la industria de harina nixtamalizada.
Geostatistical Analysis of the Colorada and Quimichule Canyons Located in Popocatépetl Volcano (Mexico) for the Prevention of Natural Disasters  [PDF]
Rogelio Ramos-Aguilar, Patricia Máximo-Romero, Blanca Susana Soto-Cruz, Salvador Alcántara-Iniesta, María de la Cruz Vázquez-García
International Journal of Geosciences (IJG) , 2016, DOI: 10.4236/ijg.2016.75054
Abstract: This paper aims to contribute to the prevention of natural disasters and generate a complement to other similar studies. The Popocatépetl volcano has showed significant and constant activity since 1994. The Colorada and Quimichule canyons are located within its geologic structure; due to their topographic features, ejected volcanic material and torrential rains in the past recent years, they put nearby communities at risk. This work presents a geostatistical analysis to obtain the gravity acceleration, slope by the distance-elevation relation, height-gravity and the fluid force on the canyons. The conversion of UTM to geographical coordinates was made with the use of the program Traninv applying the ITRF2008 epoch 2010.0 Datum and the 14 Zone; the local gravity was calculated with the use of International Organization of Legal Metrology (OIML) and the statistical analysis was obtained with the use of the Geostatistical Environmental Assessment. The structural modeling was performed usingSurfer, and the spending and force were calculated using hydrological models. The correlation analysis concluded that Quimichule has the greatest gravity and that it would transport lahars faster. Mapping, geomorphological and statistical techniques and models were applied in accordance with the study to obtain the results presented here.
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