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FACTORES SOCIO-AFECTIVOS RELACIONADOS CON LAS DIFICULTADES ESCOLARES EN NI AS Y NI OS “ESTRELLA” DEL PROGRAMA PSICOMOTRICIDAD E INTERVENCIóN
Emmanuel Herrera González,Laura Delgado Tenorio,Héctor Fonseca Schmidt,Pilar Vargas Ramírez
Revista en Ciencias del Movimiento Humano y Salud , 2012,
Abstract: El presente estudio muestra los principales factores socio-afectivos relacionados con las dificultades escolares de un grupo de tres ni as y tres ni os identificados como “estrella” por el Programa Psicomotricidad e Intervención. El mismo se desarrolló a través de una metodología mixta, en la que se aplicaron el Test de Figura Humana, el Dibujo Kinético de la Familia y una entrevista a la madre de cada estudiante. Los resultados revelaron la existencia de factores conflictivos familiares que afectan el estado emocional de las y los ni os, generándoles sentimientos negativos consigo mismos que terminan afectado sus interacciones sociales y también su desempe o escolar.
HISTOLOGIA TESTICULAR HUMANA COMPARADA, ADULTO JOVEN Y SENIL HUMAN TESTICULAR HISTOLOGY IN YOUNG AND SENILE MEN
Héctor Rodríguez,Paulina Salazar,Nadia Schmidt,Patricia Torres
Revista chilena de anatomía , 1999,
Abstract: In general, sperm production decreases with advanced age in men. Therefore the present work compares the histology and cellularity of aging human testis with that of a young adult. Gonads from three patients 69 years old and testis from a young subject (aged 25 years) were examined after histological standard techniques (PAS-Haematoxyline). Histological, morphometric and cell counting analyses of testicular sections revealed that the seminiferous tubules of senile patients were of smaller diameter, with lower seminiferous epithelium, incomplete germ cell line and vacuolization of the epithelium. Sertoli cells showed a market quantitative decrease, similar to the spermatogonial and primary spermatocyte population. It is possible to postulated that in the senile individues there is a programmed damage of seminiferous epithelial cells that may result in lowered sperm production
HISTOLOGIA TESTICULAR HUMANA COMPARADA, ADULTO JOVEN Y SENIL
Rodríguez,Héctor; Salazar,Paulina; Schmidt,Nadia; Torres,Patricia; Ossandón,Enrique;
Revista chilena de anatomía , 1999, DOI: 10.4067/S0716-98681999000200009
Abstract: in general, sperm production decreases with advanced age in men. therefore the present work compares the histology and cellularity of aging human testis with that of a young adult. gonads from three patients 69 years old and testis from a young subject (aged 25 years) were examined after histological standard techniques (pas-haematoxyline). histological, morphometric and cell counting analyses of testicular sections revealed that the seminiferous tubules of senile patients were of smaller diameter, with lower seminiferous epithelium, incomplete germ cell line and vacuolization of the epithelium. sertoli cells showed a market quantitative decrease, similar to the spermatogonial and primary spermatocyte population. it is possible to postulated that in the senile individues there is a programmed damage of seminiferous epithelial cells that may result in lowered sperm production
The Bispectrum of f(R) Cosmologies
Héctor Gil-Marín,Fabian Schmidt,Wayne Hu,Raul Jimenez,Licia Verde
Physics , 2011, DOI: 10.1088/1475-7516/2011/11/019
Abstract: In this paper we analyze a suite of cosmological simulations of modified gravitational action f(R) models, where cosmic acceleration is induced by a scalar field that acts as a fifth force on all forms of matter. In particular, we focus on the bispectrum of the dark matter density field on mildly non-linear scales. For models with the same initial power spectrum, the dark matter bispectrum shows significant differences for cases where the final dark matter power spectrum also differs. Given the different dependence on bias of the galaxy power spectrum and bispectrum, bispectrum measurements can close the loophole of galaxy bias hiding differences in the power spectrum. Alternatively, changes in the initial power spectrum can also hide differences. By constructing LCDM models with very similar final non-linear power spectra, we show that the differences in the bispectrum are reduced (<4%) and are comparable with differences in the imperfectly matched power spectra. These results indicate that the bispectrum depends mainly on the power spectrum and less sensitively on the gravitational signatures of the f(R) model. This weak dependence of the matter bispectrum on gravity makes it useful for breaking degeneracies associated with galaxy bias, even for models beyond general relativity.
Marine habitats map of "Isla del Ca?o", Costa Rica, comparing Quickbird and Hymap images classification results
Fonseca,A.C; Guzmán,Héctor M; Cortés,Jorge; Soto,Carlomagno;
Revista de Biología Tropical , 2010,
Abstract: isla del ca?o is a marine protected area on the south pacific coast of costa rica, surrounded by coral reefs and coral communities. the ecology of these coral reefs has been studied for over 20 years, but they have not been mapped. maps are considered a great research, planning, management and monitoring tool. medium to high resolution images (hymap 2005 and quickbird 2007 respectively) were processed and classified in order to test and compare their accuracy in producing a marine habitat map. manta tow surveys were performed in the field for identification of 7 marine habitats 1. coral community; 2. coral reef; 3. bed rock; 4. sand; 5. sand with boulders; 6. sand with rodolyths; and 7. deep water. the overall accuracy was slightly higher using quickbird (87%) than using hymap (60%), however the difference was not significant. the map produced using quickbird was selected to represent the marine habitats of isla del ca?o. this map will help to analyze the adequate size and zoning of the marine protected area. rev. biol. trop. 58 (1): 373-381. epub 2010 march 01.
Marine habitats map of "Isla del Ca o", Costa Rica, comparing Quickbird and Hymap images classification results
A.C Fonseca,Héctor M Guzmán,Jorge Cortés,Carlomagno Soto
Revista de Biología Tropical , 2010,
Abstract: Isla del Ca o is a marine protected area on the south Pacific coast of Costa Rica, surrounded by coral reefs and coral communities. The ecology of these coral reefs has been studied for over 20 years, but they have not been mapped. Maps are considered a great research, planning, management and monitoring tool. Medium to high resolution images (HyMap 2005 and Quickbird 2007 respectively) were processed and classified in order to test and compare their accuracy in producing a marine habitat map. Manta tow surveys were performed in the field for identification of 7 marine habitats 1. Coral community; 2. Coral reef; 3. Bed rock; 4. Sand; 5. Sand with boulders; 6. Sand with rodolyths; and 7. Deep water. The overall accuracy was slightly higher using Quickbird (87%) than using Hymap (60%), however the difference was not significant. The map produced using Quickbird was selected to represent the marine habitats of Isla del Ca o. This map will help to analyze the adequate size and zoning of the marine protected area. Rev. Biol. Trop. 58 (1): 373-381. Epub 2010 March 01. Isla del Ca o es un área marina protegida en la costa del Pacífico de Costa Rica y está rodeada de arrecifes coralinos. La ecología de estos arrecifes coralinos ha sido estudiada a lo largo de 20 a os pero todavía no habían sido mapeados. Los mapas son considerados una buena herramienta de investigación, planificación, manejo y monitoreo. Imágenes de mediana y alta resolución (Hymap 2005 y Quickbird 2007 respectivamente) fueron procesadas y clasificadas con el fin de evaluar y comparar su desempe o en la elaboración de un mapa de hábitats marinos. En el campo se realizaron sondeos tipo Manta para la identificación de siete hábitats marinos: 1. Comunidad coralina; 2. Arrecife coralino; 3. Roca; 4. Arena; 5. Arena con cantos; 6. Arena con rodolitos; y 7. Agua profunda. La exactitud de la clasificación resultó un poco mayor usando Quickbird (87%) que Hymap (60%), sin embargo la diferencia no era significativa. Se seleccionó el mapa resultante de la clasificación con Quickbird para representar los hábitats marinos de Isla del Ca o. Este mapa puede ayudar a analizar el tama o adecuado y la zonificación del área marina protegida.
Factores de amplificación del suelo en función del periodo obtenidos a partir de regresiones para Costa Rica
Schmidt,ctor;
Revista Geológica de América Central , 2011,
Abstract: amplification factors for two soil types and 23 periods were obtained, using accelerographic records and their correlation with seismic parameters and local geology related to the site for costa rica. the factors were obtained from regressions between psa (pseudo spectral acceleration) for 5% damping as the dependent variable and three independent variables: magnitude, hypocentral distance and soil type at each site, defined as s ii (hard soil) and s iii (medium to soft soil). it was assumed that the condition s i (rock) does not amplify seismic waves in the range of periods defined. factors obtained for s ii shows an almost constant value throughout the range of periods for the three different data sets considered (subduction, crustal or crustal + subduction combined) and compared with amplifications obtained by other authors, especially for japan. for s iii, amplification factors obtained in this investigation for the entire data set (subduction + crustal origin) are clearly higher than those proposed by other authors for japan, mainlyabove period of 0.4 s.
Clasificación de suelos basada en el cálculo de razones espectrales en sitios donde se ubican estaciones acelerográficas de América Central. Casos de El Salvador, Nicaragua y Costa Rica
Schmidt,ctor;
Revista Geológica de América Central , 2011,
Abstract: this research applies a common soil classification for sites where most of the central american accelerographic stations are located. it is very necessary to adopt a uniform classification procedure for all sites, because usually the information provided by local agencies (accelerographic network administrators) is incomplete or based on subjective interpretations read from maps or observation of the surface geology. moreover, precise knowledge of the soil type in which accelerograms are recorded is essential to validate the records for future researches. it was considered the information provided by each local agency to assign the soil type for each site, as well as the usgs (u.s. geological survey) vs30 map and it was followed the procedure proposed by zhao et al. (2006) based on the calculation of spectral average ratios of the horizontal component on the vertical, obtained from all available records at each station. finally, it is assigned a score to each site according to coincidence or not of different mentioned classification criteria. 134 station sites were studied, which received the following qualification: a (26%), b (32%), c (17%) and d (25%), being a the best category and d the worst one. only few stations were classified as s i (rock) and s iv (soft soil). comparing the spectral ratios obtained by other authors for japan, the amplifications obtained in the present study tend to be lower in almost the whole range of periods for the four considered soil types.
Clasificación de suelos basada en el cálculo de razones espectrales en sitios donde se ubican estaciones acelerográficas de América Central. Casos de El Salvador, Nicaragua y Costa Rica Soil classification based on spectral ratios where Central American accelerographic stations are located. Cases of El salvador, Nicaragua and Costa Rica
ctor Schmidt
Revista Geológica de América Central , 2011,
Abstract: En esta investigación se aplica un método de clasificación de suelos común para los sitios donde se ubican la mayoría de las estaciones acelerográficas de América Central. Se ha evidenciado la necesidad de aplicar un procedimiento de clasificación homogéneo para todos los emplazamientos, debido a que generalmente la información que aportan las agencias locales (administradores de las redes acelerográficas), es incompleta o subjetiva, basada en interpretaciones de mapas o solamente en la observación de la geología superficial. Por otro lado, el conocimiento preciso del tipo de suelo en el cuál se registran los acelerogramas es fundamental para el uso de esos registros en el desarrollo de investigaciones. Para la asignación del tipo de suelo se consideró la información aportada por cada agencia local, así como mapas de Vs30 propuestos por el USGS (US Geologiva Survey) y se sigue el procedimiento propuesto por Zhao et al. (2006), que se basa en el cálculo del promedio de las razones espectrales de la componente horizontal sobre la vertical, obtenidas a partir de todos los registros disponibles en cada estación. Finalmente, se le asigna una calificación a cada sitio según la coincidencia o no de los distintos criterios de clasificación considerados. Se estudiaron 134 emplazamientos de estaciones acelerográficas, que obtuvieron las siguientes calificaciones: A (26%), B (32%), C (17%) y D (25%), siendo A la mejor categoría y D la más deficiente. Se obtuvieron pocas estaciones clasificadas como S I (roca) y S IV (suelo blando). Al comparar las razones espectrales con las obtenidas para Japón por otros autores, las del presente estudio tienden a ser menores en casi todo el rango de periodos para los cuatro tipos de suelo considerados. This research applies a common soil classification for sites where most of the Central American accelerographic stations are located. It is very necessary to adopt a uniform classification procedure for all sites, because usually the information provided by local agencies (accelerographic network administrators) is incomplete or based on subjective interpretations read from maps or observation of the surface geology. Moreover, precise knowledge of the soil type in which accelerograms are recorded is essential to validate the records for future researches. It was considered the information provided by each local agency to assign the soil type for each site, as well as the USGS (U.S. Geological Survey) Vs30 map and it was followed the procedure proposed by Zhao et al. (2006) based on the calculation of spectral average ratios of the
Factores de amplificación del suelo en función del periodo obtenidos a partir de regresiones para Costa Rica Soil amplification factors in terms of period derived from regressions using Costa Rican data set
ctor Schmidt
Revista Geológica de América Central , 2011,
Abstract: Se obtuvieron los factores de amplificación para dos tipos de suelo y 23 periodos, usando registros acelerográficos y su correlación con datos sismológicos y la geología local asociada al sitio, para Costa Rica. Fueron obtenidos a partir de regresiones entre el PSA (pseudo aceleración espectral) para el 5% de amortiguamiento como variable dependiente y tres variables independientes que son: la magnitud, la distancia hipocentral y el tipo de suelo en cada emplazamiento, definido como S II (suelo firme) y S III (suelo medio a blando). Se partió del supuesto de que la condición S I (roca) no amplifica las ondas sísmicas en el rango de periodos definido. Los factores obtenidos para S II muestran un valor casi constante en todo el rango de periodos, tanto para los tres distintos grupos de datos considerados (subducción, cortical o subducción + cortical combinados), como si se comparan con amplificaciones obtenidas por otros autores, en especial para Japón. Para suelo S III, los factores obtenidos en la presente investigación para todo el conjunto de datos (subducción + cortical) son evidentemente superiores a los propuestos por otros autores para Japón, principalmente a partir de 0,4 s. Amplification factors for two soil types and 23 periods were obtained, using accelerographic records and their correlation with seismic parameters and local geology related to the site for Costa Rica. The factors were obtained from regressions between PSA (pseudo spectral acceleration) for 5% damping as the dependent variable and three independent variables: magnitude, hypocentral distance and soil type at each site, defined as S II (hard soil) and S III (medium to soft soil). It was assumed that the condition S I (rock) does not amplify seismic waves in the range of periods defined. Factors obtained for S II shows an almost constant value throughout the range of periods for the three different data sets considered (subduction, crustal or crustal + subduction combined) and compared with amplifications obtained by other authors, especially for Japan. For S III, amplification factors obtained in this investigation for the entire data set (subduction + crustal origin) are clearly higher than those proposed by other authors for Japan, mainlyabove period of 0.4 s.
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