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Search Results: 1 - 10 of 202035 matches for " Rivas P "
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Modificaciones Estructurales en el Estómago y el Hígado de Paralabrax maculatofasciatus (Steindacher, 1868) ante Situaciones de Estrés Crónico
Zacarías,M; Cadena,M; Rivas,P;
International Journal of Morphology , 2009, DOI: 10.4067/S0717-95022009000200019
Abstract: to determine stress effects at histological level in the digestive system, organisms of paralabrax maculatofasciatus were submitted to 2 stress models. one of decreasing the water level (n=84) for 30 and 60 min daily, and another at high density cultures (n=96) of 1.6 and 3.2 kg/1001. stomach and the liver samples were fixed in 10% formalin, embedded in paraffin wax, sectioned at 6 urn and stained with haematoxylin-eosin. in both stress conditions, the stomach showed important morphological changes in the mucosa layer, such as hypertrophy and atrophy. in the liver, coloration and texture changes were observed as well as haemolisis, inflammation and necrosis. in the water decrease model, the mucosa layer of stomach showed significant morphometric differences (p<0.05), between different times of stress exposure and/or between different days, in some of the measured parameters. in the high-density model, significant differences in the stomach mucosa showed a sampling-density interaction in 4 parameters and 6 other parameters showed differences with no interaction. liver showed significant differences in nuclear perimeter between sampling-days. stress caused by high-density culture proved to be the factor that caused the most serious tissue damage.
CAPACIDAD COMBINATORIA PARA RENDIMIENTO DE GRANO Y CARACTERES DE CALIDAD MALTERA EN CEBADA (Hordeum vulgare L.)
Rivas P.,Rudy; Barriga B.,Patricio;
Agricultura Técnica , 2002, DOI: 10.4067/S0365-28072002000300001
Abstract: six spring barley (hordeum vulgare l.) genotypes were crossed in a diallel system to study combining ability for grain yield and twelve malting quality traits. the f1 hybrids behavior was analyzed using griffing?s model i, method 2. the analysis for general combining ability (ccg), specific combining ability (cce) and the relationship ccg/cce showed that expression of eight out of the thirteen traits were associated with genes which were additive in their effects: grain weight, malt extract, viscosity, friability, malt protein, soluble protein, kolbach index and free amino nitrogen (fan). on the other hand, the expression of grain plumpness, extract difference and the hartong index showed both additive and non-additive genetic control, the former being of greater magnitude. only grain yield and diastatic power had mainly non-additive control, even though additive effects were also present.
ARECO INIA, CULTIVAR CHILENO DE AVENA PARA PRODUCCIóN DE FORRAJE EN ARGENTINA
Beratto M.,Edmundo; Rivas P.,Rudy;
Agricultura Técnica , 2003, DOI: 10.4067/S0365-28072003000200011
Abstract: areco inia is a new alternative oat (avena sativa l.) cultivar for forage production in argentina. it was obtained from a cross between the advanced lines ave 85.103 and ave 78.106 carried out in 1987 at the carillanca regional research center, of the national agricultural research institute, located near temuco, chile. in chile, areco inia has been included in yield trials since 1995. in argentina, it has been evaluated mainly for forage production in 1998 and 1999 in lujan, and for disease reactions in lujan and chacabuco (buenos aires province) and maciel (santa fe province), by trigen seed services llc (tgss). areco inia has good resistance to the most common oat diseases in argentina, and it is comparable or superior to other oat cultivars in that country.
CORAL INIA, CULTIVAR DE AVENA PARA PRODUCCIóN DE FORRAJE EN ARGENTINA
Beratto M.,Edmundo; Rivas P.,Rudy;
Agricultura Técnica , 2003, DOI: 10.4067/S0365-28072003000200012
Abstract: coral-inia is an alternative oat (avena sativa l.) cultivar for forage production in argentina. it was obtained from a segregant f3 population from the quaker oat 1991 nursery, corresponding to entry 184, identified as qr 856 with origin 90wi3125-28. in chile, coral inia has been included in yield trials from 1995 to 1997 at the carillanca research center, of the national agricultural research institute (inia), located near temuco, chile. in argentina it has been evaluated for forage production from 1998 to 1999 in lujan (buenos aires province), and for disease reactions in lujan and chacabuco (buenos aires province) and maciel (santa fe province), by trigen seed services llc (tgss). coral inia has shown good resistance to lodging and the main oat diseases in argentina.
Matriz dise?ada en toxicología ocupacional
Tamayo Rivas,Sheila; Argota Pérez,George;
MEDISAN , 2012,
Abstract: a matrix was designed to prevent the risk in occupational toxicology, structured in 3 evaluation sections (presumed risk, advice risk and risk of working conditions and damages to health). five menus were considered in the first section (sector, chemicals, referred toxicity, biomarkers and sentinel events); 6 in the second section (frequency of exposure, length of exposure, proximity to the source, means of protection and influence of posts) and 2 in the third one (evaluation of working conditions and damages to health). given that it is a new management tool to estimate the toxicological risk, it contributes to preserve health in the work place.
Factor de condición biológico-ambiental en la Gambusia punctata y sus efectos para el control biológico larval
Argota Pérez,George; Tamayo Rivas,Sheila;
MEDISAN , 2012,
Abstract: in this paper the biological condition factor was evaluated in the species gambusia punctata as an expression of environmental damage of san juan river in santiago de cuba, for which the total length of the fish was related to the total weight. two study sites were selected in the upper and lower river basins, and samplings were performed during the dry season of 2011. individuals of both sexes were chosen which biometrically measured between 1.8 and 3.1 cm in total length and 2 class intervals were established. the fishes living in the upper river had higher biological condition factor (0.068 > 0.038). it was concluded that given the values of this factor, the environmental quality of the ecosystem affects the development of the species, which could influence their predatory capacity and therefore as biological control of mosquito larvae.
Discourse Intonation and Systemic Functional Phonology
Germani,Miriam P; Rivas,Lucía I;
Colombian Applied Linguistics Journal , 2011,
Abstract: this paper is a reflection on praxis which addresses the phonological stratum as an integral part of the language system. as efl teacher trainers, we often find that students isolate the different meaning-creating components of language as a natural result of the way courses are organized at university level. it is in the spirit of helping students integrate the various aspects of language and context that we have set out to compare david brazil, malcolm coulthard and catherine johns's discourse intonation model -which we have been working with for more than ten years- with the intonation approach in systemic functional linguistics, by m.a.k. halliday and william greaves. we observe the theoretical similarities between the two approaches in order to see how they may supplement one another. then, we analyse a conversation taken from a film following both theoretical approaches, and draw conclusions in the light of the comparison. our preliminary results show that the two approaches explain the meanings conveyed with reference to different meaning-making resources. brazil et al. explain the meanings at risk in the interaction according to the phonological systems they describe (prominence, tone, key and termination). halliday and greaves do so by referring to the phonological and lexico-grammatical strata in combination.
Modificaciones Estructurales en el Estómago y el Hígado de Paralabrax maculatofasciatus (Steindacher, 1868) ante Situaciones de Estrés Crónico Structural Modifications in the Stomach and Liver of Paralabrax maculatofasciatus (Steindacher, 1868) under Chronic Stress Conditions
M Zacarías,M Cadena,P Rivas
International Journal of Morphology , 2009,
Abstract: Para determinar el efecto del estrés a nivel del aparato digestivo, organismos de la especie Paralabrax maculatofasciatus fueron sometidos a dos modelos de estrés: el primero por descenso en el nivel del agua (n=84) por 30 y 60 minutos diariamente, y el segundo por cultivo a altas densidades (n=96) de 1,6 y 3,2 kg/100 1. Se tomaron muestras de estómago e hígado y se fijaron en formol al 10%. Los tejidos fueron incluidos en parafina, realizándose cortes de 6 um que se ti eron con H-E. En ambas condiciones de estrés el estómago presentó cambios morfológicos importantes tales como hipertrofia y atrofia en la capa mucosa. En el hígado se observaron cambios de coloración y textura, así como hemolisis, inflamación y necrosis. Por descenso en el nivel del agua el estómago presentó diferencias morfométricas significativas (P<0,05), entre los diferentes tiempos de exposición al estrés y/o entre los días de muestreo en algunos de los parámetros medidos. Por cultivo a altas densidades, se observaron diferencias significativas en algunos parámetros, 4 de ellos presentaron interacción densidad-muestreo y el resto presentaron diferencias significativas sin interacción. El hígado presentó diferencias significativas (P<0,05) en el perímetro nuclear entre los diferentes días de muestreo. El estrés provocado por alta densidad de cultivo resultó ser el factor que provocó da os tisulares más severos en los órganos estudiados, de ahí la importancia de mantener las condiciones adecuadas en los cultivos, como son el nivel de agua y el número de organismos por estanque. To determine stress effects at histological level in the digestive system, organisms of Paralabrax maculatofasciatus were submitted to 2 stress models. One of decreasing the water level (n=84) for 30 and 60 min daily, and another at high density cultures (n=96) of 1.6 and 3.2 Kg/1001. Stomach and the liver samples were fixed in 10% formalin, embedded in paraffin wax, sectioned at 6 urn and stained with haematoxylin-eosin. In both stress conditions, the stomach showed important morphological changes in the mucosa layer, such as hypertrophy and atrophy. In the liver, coloration and texture changes were observed as well as haemolisis, inflammation and necrosis. In the water decrease model, the mucosa layer of stomach showed significant morphometric differences (P<0.05), between different times of stress exposure and/or between different days, in some of the measured parameters. In the high-density model, significant differences in the stomach mucosa showed a sampling-density interaction in 4 parameters and 6 other
CAPACIDAD COMBINATORIA PARA RENDIMIENTO DE GRANO Y CARACTERES DE CALIDAD MALTERA EN CEBADA (Hordeum vulgare L.) Combining ability for grain yield and malting quality traits in barley (Hordeum vulgare L.)
Rudy Rivas P.,Patricio Barriga B.
Agricultura Técnica , 2002,
Abstract: Se cruzaron seis genotipos de cebada de ciclo de desarrollo primaveral en un arreglo dialelo, con el fin de estudiar sus capacidades combinatorias para rendimiento de grano y doce caracteres de calidad maltera. El comportamiento de los híbridos F1 fue analizado utilizando el Modelo I, método 2 de Griffing. El análisis de capacidad combinatoria general (CCG), de capacidad combinatoria específica (CCE) y la relación CCG/CCE, demostraron que ocho de los trece caracteres estudiados mostraron expresión asociada a efectos génicos de tipo aditivo, que fueron: peso de grano, extracto de malta, viscosidad, friabilidad, proteína de la malta, proteína soluble, índice de Kolbach y amino nitrógeno libre (FAN: free amino nitrogen). Por otra parte en la expresión de los caracteres calibre de grano, diferencia del extracto, e índice de Hartong fueron importantes tanto los efectos aditivos como los no aditivos, siendo los primeros de mayor magnitud. Solo el rendimiento de grano y el poder diastásico mostraron predominio de acción génica de tipo no aditivo (dominancia y sobredominancia), aunque los efectos aditivos también estuvieron presentes. Six spring barley (Hordeum vulgare L.) genotypes were crossed in a diallel system to study combining ability for grain yield and twelve malting quality traits. The F1 hybrids behavior was analyzed using Griffing’s Model I, method 2. The analysis for general combining ability (CCG), specific combining ability (CCE) and the relationship CCG/CCE showed that expression of eight out of the thirteen traits were associated with genes which were additive in their effects: grain weight, malt extract, viscosity, friability, malt protein, soluble protein, Kolbach index and free amino nitrogen (FAN). On the other hand, the expression of grain plumpness, extract difference and the Hartong index showed both additive and non-additive genetic control, the former being of greater magnitude. Only grain yield and diastatic power had mainly non-additive control, even though additive effects were also present.
Matriz dise ada en toxicología ocupacional Matrix designed in occupational toxicology
Sheila Tamayo Rivas,George Argota Pérez
MEDISAN , 2012,
Abstract: Se dise ó una matriz para prevenir el riesgo en toxicología ocupacional, estructurada en 3 secciones de evaluación (riesgo presumible, riesgo de asesoría y riesgo de condiciones de trabajo y da os a la salud). Se consideraron 5 menús en la primera (sector, agentes químicos, toxicidad referida, biomarcadores y eventos centinelas); 6 en la segunda (frecuencia de la exposición, duración de la exposición, proximidad a la fuente, medios de protección e influencia de puestos) y 2 en la tercera (evaluación de las condiciones de trabajo y da os a la salud). Toda vez que constituye un nuevo instrumento de gestión para estimar el riesgo toxicológico, contribuye a preservar la salud laboral. A matrix was designed to prevent the risk in occupational toxicology, structured in 3 evaluation sections (presumed risk, advice risk and risk of working conditions and damages to health). Five menus were considered in the first section (sector, chemicals, referred toxicity, biomarkers and sentinel events); 6 in the second section (frequency of exposure, length of exposure, proximity to the source, means of protection and influence of posts) and 2 in the third one (evaluation of working conditions and damages to health). Given that it is a new management tool to estimate the toxicological risk, it contributes to preserve health in the work place.
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