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Search Results: 1 - 10 of 568786 matches for " Angel A. Villafa?e Santiago "
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HIJOS ADULTOS DE MADRES/PADRES ALCOHóLICOS Y FACTORES DE RIESGO PSICOLóGICOS EN ESTUDIANTES UNIVERSITARIOS (ADULT CHILDREN OF ALCOHOLIC PARENTS AND PSYCHOLOGICAL RISK FACTORS IN UNIVERSITY STUDENTS)
Jiménez Chafey María Isabel,Serra Taylor José A.,Villafae Santiago Angel A.,Jiménez Pastrana Wilda
Revista Electrónica Actualidades Investigativas en Educación , 2011,
Abstract: Resumen:El propósito principal de la investigación presentada en este artículo fue identificar la prevalencia de hijos adultos de padres/madres alcohólicos (HADA) en estudiantes universitarios de nuevo ingreso. Se exploró la presencia de factores de riesgo psicológicos (autoestima, codependencia, síntomas de ansiedad y depresión) y se compararon estas variables entre los HADA y los No-HADA. Se administró un cuestionario de auto-reporte a la población universitaria del recinto de Río Piedras de la Universidad de Puerto Rico donde el 23% de la muestra reporta ser HADA. Los resultados generales revelaron que existen diferencias significativas entre los HADA y no-HADA en síntomas de ansiedad, depresión, codependencia y autoestima; los HADA presentan menor autoestima, más indicadores de codependencia y mayores síntomas de depresión y ansiedad. Se encontró una relación positiva significativa entre ser HADA y síntomas de ansiedad, depresión y codependencia, así como una relación negativa significativa y autoestima. Estos hallazgos sugieren que una población significativa de estudiantes de nuevo ingreso podría estar en alto riesgo de presentar dificultades en la salud mental que pueden incidir en su desarrollo académico, personal y profesional. Por lo tanto, se deben desarrollar estrategias efectivas de identificación temprana e intervención en los centros de consejería para trabajar con esta población.Abstract: The main objective of this article is to present the results of a study that explored the prevalence of Adult Children of Alcoholics (ACOA) in first year students. The prevalence of psychological risk factors (codependence, self-esteem, symptoms of depression and anxiety) was explored and compared between ACOA and non-ACOA students. A self-report questionnaire measuring the variables of interest was administered to the population of first year students at the University of Puerto Rico, Rio Piedras Campus. Twenty three percent of the sample reported being ACOA. The general results reveal that there were significant differences between ACOA and non-ACOA in symptoms of depression and anxiety, codependence and self-esteem; ACOAs presented lower self-esteem, higher codependence and more symptoms of depression and anxiety. A positive significant relationship was found between being an ACOA and symptoms of depression and anxiety, and codependence, as well as a significant negative relationship and self-esteem. These results suggest that first year students might be a population at higher risk of presenting mental health difficulties that can impact their acade
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. Villafae 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.
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 Villafae 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.
Distribución espacial de la humedad en tres perfiles de un suelo regado por goteo
Moreno,María Alejandra; Villafae,Roberto;
Bioagro , 2009,
Abstract: since soil spatial variability may affect the moist distribution of a drip irrigated soil, it was studied the moist distribution pattern in three soil profiles. the study was carried out at the experimental field of the agronomy school of the universidad central de venezuela, in the city of maracay. drip irrigation was applied using a naan paz 25 line with 1.7 l·h-1 emitters located every 33 cm. three sites selected and soil samples were taken by stratum for bulk density, hydraulic conductivity and texture determinations. two water volumes were applied (20 and 40 liters per plant) by varying the irrigation time, and soil samples were taken in each site at different depths and distances of the irrigation line for moisture determinations. it was also measured the surface moistened area along the irrigation line. the results were interpreted according to the physical properties of each soil profile. the three profiles showed to be different in their stratification but the moist distribution generated by emitters was similar, with few differences attributed to surface sealing and rough micro-relief, factors that should be considered in the design of trickle irrigation systems.
Distribución espacial de la humedad en tres perfiles de un suelo regado por goteo Spatial distribution of moisture in three soil profiles under trickle irrigation
María Alejandra Moreno,Roberto Villafae
Bioagro , 2009,
Abstract: Dado que la variabilidad espacial del suelo puede afectar la distribución en el perfil del agua aplicada mediante un sistema de goteo, se estudió la distribución espacial de la humedad en tres perfiles de suelo. El estudio fue realizado en el campo experimental de la Facultad de Agronomía de la Universidad Central de Venezuela, en Maracay, y el riego se aplicó mediante una manguera Naan PAZ 25 con goteros integrados, separados cada 33 cm y con descarga cada uno de 1,7 L·h-1. Dentro del área del estudio se ubicaron tres sitios donde se tomaron muestras de suelo por estrato para la determinación de densidad aparente, conductividad hidráulica y textura. Se aplicaron dos volúmenes diferentes de agua (20 y 40 litros por planta) mediante la variación del tiempo de aplicación, y posteriormente, se tomaron muestras para determinar la humedad a distintas profundidades y distancias de la línea de goteo. También fue medido en superficie el área de mojado producido por la cinta de goteo. Los resultados fueron interpretados según las propiedades físicas de cada sitio de muestreo. Los tres sitios mostraron ser diferentes en cuanto a su estratificación pero el comportamiento de la distribución de la humedad generada por los emisores resultó similar, con ligeras variaciones, atribuidas a la formación de sello sobre la superficie del suelo y el micro-relieve irregular, factores que deben ser considerados en las evaluaciones con fines de dise o. Since soil spatial variability may affect the moist distribution of a drip irrigated soil, it was studied the moist distribution pattern in three soil profiles. The study was carried out at the experimental field of the Agronomy School of the Universidad Central de Venezuela, in the city of Maracay. Drip irrigation was applied using a Naan PAZ 25 line with 1.7 L·h-1 emitters located every 33 cm. Three sites selected and soil samples were taken by stratum for bulk density, hydraulic conductivity and texture determinations. Two water volumes were applied (20 and 40 liters per plant) by varying the irrigation time, and soil samples were taken in each site at different depths and distances of the irrigation line for moisture determinations. It was also measured the surface moistened area along the irrigation line. The results were interpreted according to the physical properties of each soil profile. The three profiles showed to be different in their stratification but the moist distribution generated by emitters was similar, with few differences attributed to surface sealing and rough micro-relief, factors that should be considered
Respuesta a las condiciones ambientales y al manejo agronómico del suelo de cuatro tipos comerciales de ajo en Famatina, La Rioja. Argentina
Saluzzo, J.A.,Villafae, N.
Horticultura Argentina , 2009,
Abstract: Changes in chemical properties and nutrients availability of the soil have been yielded by management practices to garlic (Allium sativum L.) crop to assess the dry matter production of four garlic types during two growing years. Six soil treatments combined oats (Avena sativa L.) and alfalfa (Medicago sativa L.) crops, chemical fertilization and goat faeces. Dry matter production differences between garlic types (purple, white, red and brown) were related to soil treatements and thermal conditions in each year. Dry matter accumulated into the inflorescence stalk was modified by year and soil conditions. The use of chemical fertilizers a three-year period lowered the bulb harvest index and tended to increase dry matter accumuled into the inflorescence stalk. Yield and accumulated dry matter into the bulb were enhanced by nutrients availability from the soil treatment with chemical fertilizers (200, 30 y 30 kg·ha-1 de N, P2O5 y K2O, respectively) and 23 t·ha-1 goat faeces preceeded by oats. Moreover, for this soil handling, the production of early garlic (purple and white types) is the most suitable for the ambient conditions of the region.------------------------------------------------------------------------------------------------------------------- Se generaron cambios en las propiedades químicas y disponibilidad de nutrientes del suelo mediante prácticas de manejo del suelo para evaluar la producción de materia seca de cuatro tipos comerciales de ajo (Allium sativum L.) durante dos a os de cultivo.Seis tratamientos de suelo combinaron el empleo de cultivos de avena (Avena sativa L.) y alfalfa (Medicago sativa L.),fertilización química y abono caprino. Las diferencias en los niveles de producción de materia seca entre los cuatro tipos de ajo (morado, blanco, colorado y casta o) estuvieron relacionadas con los tratamientos de suelo y las condiciones térmicas de cada a o. La materia seca acumulada en el tallo floral fue afectada por el a o y las condiciones de manejo del suelo. El empleo de fertilizantes químicos tres a os consecutivos provocó mermas en el índice de cosecha del bulbo y tendió a incrementar la materia seca acumulada en el escapo floral. La producción y acumulación de materia seca en el bulbo fueron favorecidos por la adecuada disponibilidad de nutrientes del tratamiento de suelo con uso de fertilizantes químicos (200, 30 y 30 kg·ha-1 de N, P2O5 y K2O, respectivamente) y 23 t·ha-1 de abono caprino precedido por cultivo de avena. Además, con este manejo del suelo, la producción de ajos tempranos (tipos morado y blanco) es la más convenie
Cambios en la riqueza taxonómica y en las tasas de primera y última aparición de los Proterotheriidae (Mammalia, Litopterna) durante el Cenozoico
Villafae, A. L.,Ortiz-Jaureguizar, E.,Bond, M.
Estudios Geologicos , 2006, DOI: 10.3989/egeol.0662115
Abstract: The Proterotheriidae have been recorded from Upper Paleocene until Holocene [ Land-mammal Ages (= SALMAs) Itaboraian-Lujanian]. They are mainly braquiodonts, with cursorial habits, small to medium sized, and an early tendency toward the monodactily. The objectives of this paper are: 1) to analyze the changes in the diversity and faunistic exchange rates of these South American ungulates (at genus and species levels) throughout the biochron of the family; and 2) to relate these changes with the principal changes in climatic-environmental conditions. The results show that Proterotheriidae suffered marked changes in the generic and specific diversity during the Itaboraian-Lujanian SALMAs, with four diversity peaks: two minors in the Casamayoran and Laventan SALMAs, and two majors in the Santacrucian and Huayquerian ones. These peaks were interrupted by two hiatuses in the fossil record, the first in the Divisaderan-Tinguirirican SALMAs, and the second in the Mayoan SALMA. In general, Proterotheriidae show an elevated exchange rate during its biochron, both at genus as well as species levels. This elevated exchange rate indicates that the family possesses a higher biochronological value. Both the fluctuations in taxonomic richness as well as exchange rates are related with the climatic-environmental changes occurred during the Cenozoic. As a rule, higher diversity is observed in those SALMAs in which there is a relatively equalized relation between forests and grasslands. On the other hand, diversity markedly falls when the environments change from wet and closed to most open and arid. The last Proterotheriidae species (Neolicaphrium recens) was confined to the Pleistocene of north-eastern Argentina and western Uruguay, where an ecotone between forests and grasslands is recorded. Los Proterotheriidae han sido registrados desde el Paleoceno Superior hasta el Holoceno [ Edadesmamífero (= SALMAs) Itaboraiense-Lujanense]. Son mayoritariamente braquiodontes, cursoriales, de tama o peque o a mediano, que muestran una temprana tendencia hacia la monodactilia. Los objetivos del presente trabajo son: 1) analizar los cambios en la diversidad y las tasas de recambio de estos ungulados sudamericanos (tanto a nivel de especies como de géneros) a lo largo de todo su biocrón; y 2) vincular estos cambios con las principales variaciones en las condiciones climático-ambientales. Los resultados muestran que durante el lapso comprendido entre las SALMAs Itaboraiense-Lujanense, los Proterotheriidae sufren grandes cambios en la diversidad genérica y específica, con cu
Acumulación de iones y solutos orgánicos en hojas de plantas de ca?a de azúcar cultivadas en dos tablones comerciales afectados por sales
García,Marina; Medina,Ernesto; Villafae,Roberto;
Bioagro , 2009,
Abstract: a field sampling was carried out to determine the relationship between the soil salinity and its ionic composition with the accumulation of ions and organic solutes in leaves of a sugarcane genotype pr692176 growing in salt-affected fields. two commercial fields were chosen and samples of soil and leaves differing in age were sampled. in the soil samples the electrical conductivity of the saturation extract (ece) and its saline composition were measured, and in the leaves the concentrations of na+, k+, ca+2, mg+2, cl-, so4-2, soluble sugars and proline were determined. in one field mgso4 y na2so4 were the dominant salts, whereas nacl was the dominant salt in the other. the concentration of salts in leaves increased with the ece, with the highest values in the older leaves and the sheaths. in the field with nacl as the dominant salt, the sheaths accumulated more cl- than the blades, and the contrary was observed in the case of na+, being the na/cl ratio lower than one in both tissues. leaf k+ concentration decreased as ece increased. in the soil with high content of mgso4 the concentration of ca+2 and the ca/mg ratio was notably reduced. the concentration of non reducing sugars and proline increased with ece, suggesting a relationship between the foliar accumulation of these solutes and the tolerance of this genotype to saline conditions.
Evaluación de un equipo de reflectometría de dominio temporal (TDR) para registros de humedad en un suelo franco
Murillo,J; Villafae,R; Basso,C; Trujillo,A;
Revista de la Facultad de Agronomía , 2008,
Abstract: the technique of time domain reflectometry (tdr) is being used to monitor soil water content, but manufacturer's calibration does not necessarily agree with each specific soil condition. therefore, it is important to assess the probe in each soil where its use be planned. in this study, an evaluation was carried out for a wide range of moisture content, in a fertirrigated loam soil located at the experimental field at the school of agronomy in maracay, venezuela, comparing the volumetric water content (vwc) obtained by tdr with the vwc determined in soil samples taken depth 10 cm and 20 cm below the soil surface. it was found a strong lineal correlation between vwc measured in samples and vwc obtained by tdr probe (r = 0.88 for depth 10 cm and 0.95 for depth 20 cm; respectively). otherwise, regression equations (r2 adjusted = 77.6% for depth 10 cm and 90.5% for depth 20 cm) showed that tdr must overestimate soil water content; its lectures were higher (140-148% in top 10 cm and 164-170% in top 20 cm) than those were measured in soil samples, making it clear calibration is necessary.
Acumulación de iones y solutos orgánicos en hojas de plantas de ca a de azúcar cultivadas en dos tablones comerciales afectados por sales Ions and organic solutes accumulation in leaves of sugar cane plants growing in two salt affected commercial fields
Marina García,Ernesto Medina,Roberto Villafae
Bioagro , 2009,
Abstract: Se realizó un muestreo de campo con el objetivo de estudiar la relación de la salinidad del suelo con la acumulación de iones inorgánicos y solutos orgánicos en hojas del genotipo de ca a de azúcar PR692176 cultivado en tablones afectados por sales. Se seleccionaron dos tablones comerciales, donde se tomaron muestras de suelo y de hojas con edad distinta. En los suelos se determinó la conductividad eléctrica del extracto (CEe) y la composición iónica, y en las hojas la concentración de Na+, K+, Ca+2, Mg+2, Cl-, SO4-2, azúcares solubles y prolina. Las sales predominantes en un tablón fueron MgSO4 y Na2SO4, y en el otro, NaCl. La concentración salina en las hojas incrementó a medida que aumentó la CEe, resultando mayor en la vaina foliar y en la hoja más madura. En el tablón con predominio de NaCl, la vaina foliar acumuló más Cl- que la lámina y lo contrario ocurrió con el Na+, siendo la relación Na/Cl menor que uno en ambos tejidos; la concentración foliar de K+ se redujo en ambas porciones de la hoja con el incremento en la CEe. En el suelo con alto contenido de MgSO4, la concentración de Ca+2 y la relación Ca/Mg en las hojas disminuyó considerablemente. La concentración de azúcares no reductores y de prolina aumentó a medida que se incrementó la CEe, lo que sugiere una vinculación entre la acumulación foliar de estos solutos y la tolerancia de este genotipo a condiciones salinas. A field sampling was carried out to determine the relationship between the soil salinity and its ionic composition with the accumulation of ions and organic solutes in leaves of a sugarcane genotype PR692176 growing in salt-affected fields. Two commercial fields were chosen and samples of soil and leaves differing in age were sampled. In the soil samples the electrical conductivity of the saturation extract (ECe) and its saline composition were measured, and in the leaves the concentrations of Na+, K+, Ca+2, Mg+2, Cl-, SO4-2, soluble sugars and proline were determined. In one field MgSO4 y Na2SO4 were the dominant salts, whereas NaCl was the dominant salt in the other. The concentration of salts in leaves increased with the ECe, with the highest values in the older leaves and the sheaths. In the field with NaCl as the dominant salt, the sheaths accumulated more Cl- than the blades, and the contrary was observed in the case of Na+, being the Na/Cl ratio lower than one in both tissues. Leaf K+ concentration decreased as ECe increased. In the soil with high content of MgSO4 the concentration of Ca+2 and the Ca/Mg ratio was notably reduced. The concentration of non reducing sugars
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