oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2020 ( 5 )

2019 ( 447 )

2018 ( 571 )

2017 ( 592 )

Custom range...

Search Results: 1 - 10 of 359298 matches for " Andrés; Rodríguez-Romero "
All listed articles are free for downloading (OA Articles)
Page 1 /359298
Display every page Item
Aproximación a las modas administrativas desde algunos conceptos sociológicos: El caso de la reingeniería
Mari?o-Arévalo,Andrés; Rodríguez-Romero,Carlos Alberto;
Innovar , 2011,
Abstract: administrative fads, as contemporary theoretical developments of administration, have been characterized by being temporary and responding to the needs of the market economy, which seeks solutions in administration in order to resolve the crises in which they have been immersed in recent years. this article sets out to analyze reengineering, as one of the most representative developments of the phenomenon of administrative fads, understanding the context in which it arose, its main characteristics and the reasons for their particular names. the aim is to analyze them in the light of certain proposals that have originated in other disciplines such as 'blackmail of the enlightenment' and its critical ontology in the subject-organization interrelationship. these developments have moved away from contributions from other branches of knowledge such as psychology, sociology, anthropology or political science, among others, in the framework of a recognition of the complexity of organizations, and thereby vindicate the central role that the human being must occupy in organizations, and which has made it difficult for the management of organizations to serve as the backbone for growth and socioeconomic development.
Dimorfismo sexual de Aspidoscelis costata costata (Squamata: Teiidae) en el sur del Estado de México, México Sexual dimorphism of Aspidoscelis costata costata (Squamata: Teiidae) in the south of the State of Mexico, Mexico
MAGDALENA AGUILAR-MORENO,FELIPE DE J RODRíGUEZ-ROMERO,ANDRéS ARAGóN-MARTíNEZ,JOSé A MU?OZ-MANZANO
Revista chilena de historia natural , 2010,
Abstract: El dimorfismo sexual es una característica extendida en lacertilios y se relaciona con la adecuación de los individuos. En este estudio se analizó si Aspidoscelis costata costata (Squamata) presenta dimorfismo sexual al sur del Estado de México, México, especialmente en relación a su forma corporal altamente conservada dentro de la familia Teiidae. La población estudiada habita a 1500 msnm. Se utilizaron individuos adultos que fueron capturados y liberados durante estudios ecológicos. Para cada individuo se registró la longitud hocico-cloaca, el peso corporal, largo de la cabeza, ancho de la cabeza, alto de la cabeza, longitud del fémur y distancia interaxilar. Los análisis realizados indicaron que los machos fueron más grandes en longitud hocico-cloaca y peso; además presentaron dimensiones más grandes en cabeza y fémur que hembras de la misma longitud hocico-cloaca. La distancia interaxilar fue mayor en hembras que en machos de la misma longitud hocico-cloaca. El dimorfismo sexual de A. costata costata puede explicarse por selección sexual y selección por fecundidad. Sexual dimorphism is a widespread characteristic in lizards, and it has been related to the individual fitness. Sexual dimorphism was investigated in Aspidoscelis costata costata (Squamata) to the south of the State of Mexico, Mexico, relating to its body proportions highly similar within the Teiidae. Study area was located at 1500 m. Adult individuals from mark-recapture study were used. Morphometric characteristics were measured in individuals of A. costata costata: snout-vent length, mass, head length, head width, head height, femur length and interlimb length. Males were larger than females for SVL and mass. At the same body, males had longer heads and femur and shorter interlimb length than did conspecific females. The sexual dimorphism of A. costata costata can be explained by selection sexual selection and fecundity selection.
Effects of a Buried Cysteine-To-Serine Mutation on Yeast Triosephosphate Isomerase Structure and Stability
Alejandra Hernández-Santoyo,Lenin Domínguez-Ramírez,César A. Reyes-López,Edith González-Mondragón,Andrés Hernández-Arana,Adela Rodríguez-Romero
International Journal of Molecular Sciences , 2012, DOI: 10.3390/ijms130810010
Abstract: All the members of the triosephosphate isomerase (TIM) family possess a cystein residue (Cys126) located near the catalytically essential Glu165. The evolutionarily conserved Cys126, however, does not seem to play a significant role in the catalytic activity. On the other hand, substitution of this residue by other amino acid residues destabilizes the dimeric enzyme, especially when Cys is replaced by Ser. In trying to assess the origin of this destabilization we have determined the crystal structure of Saccharomyces cerevisiae TIM (ScTIM) at 1.86 ? resolution in the presence of PGA, which is only bound to one subunit. Comparisons of the wild type and mutant structures reveal that a change in the orientation of the Ser hydroxyl group, with respect to the Cys sulfhydryl group, leads to penetration of water molecules and apparent destabilization of residues 132–138. The latter results were confirmed by means of Molecular Dynamics, which showed that this region, in the mutated enzyme, collapses at about 70 ns.
Dimorfismo sexual de Aspidoscelis costata costata (Squamata: Teiidae) en el sur del Estado de México, México
AGUILAR-MORENO,MAGDALENA; RODRíGUEZ-ROMERO,FELIPE DE J; ARAGóN-MARTíNEZ,ANDRéS; MU?OZ-MANZANO,JOSé A; GRANADOS-GONZáLEZ,GISELA; HERNáNDEZ-GALLEGOS,OSWALDO;
Revista chilena de historia natural , 2010, DOI: 10.4067/S0716-078X2010000400011
Abstract: sexual dimorphism is a widespread characteristic in lizards, and it has been related to the individual fitness. sexual dimorphism was investigated in aspidoscelis costata costata (squamata) to the south of the state of mexico, mexico, relating to its body proportions highly similar within the teiidae. study area was located at 1500 m. adult individuals from mark-recapture study were used. morphometric characteristics were measured in individuals of a. costata costata: snout-vent length, mass, head length, head width, head height, femur length and interlimb length. males were larger than females for svl and mass. at the same body, males had longer heads and femur and shorter interlimb length than did conspecific females. the sexual dimorphism of a. costata costata can be explained by selection sexual selection and fecundity selection.
Síndromes talamésicos. Nuevos conceptos y estado actual del conocimiento en Costa Rica
Sáenz-Renauld,German F; Rodríguez-Romero,Walter;
Acta Médica Costarricense , 2006,
Abstract: while for abnormal hemoglobins it is possible to use anthropological markers to establish their origins, the thalassemias have a very wide distribution in ancestral populations. thalassemias are the world's most common monogenic disorders. the dispersion of b thalassemia in the mediterranean region, the middle east, the southeastern part of asia, the indian subcontinent and other regions, indicate that their genetic origins were independent. a thalassemia shows a similar pattern (southeastern part of asia, southern china, philippines, africa and the mediterranean). in costa rica thalassemia is found in the black population with two alleles (a+ (a1) 23% and ao (a2) 3.9%). sporadic double heterozygous cases of hb h disease (a+/ao), are from oriental population. special reference is made of minor b thalassemia and their important differentiation with iron deficiency anemia. eight major b thalassemia cases have been described in our country. intermediate thalassemia cases with or without hb s are not infrequent. a short commentary is made of the pathophysiology of b thalassemia and the treatment in developed countries.
Síndromes talamésicos. Nuevos conceptos y estado actual del conocimiento en Costa Rica
German F Sáenz-Renauld,Walter Rodríguez-Romero
Acta Médica Costarricense , 2006,
Abstract: En tanto que para las hemoglobinas Hbs anormales es posible determinar los lugares de su origen (marcadores antropológicos), en las enfermedades talasémicas se tiene el problema de su amplia distribución en las principales poblaciones ancestrales. Las talasemias resultan ser las enfermedades monogénicas más comunes en el mundo. La amplia dispersión de la B talasemia en todo el Mediterráneo, el Medio Este de Asia, el sudeste Asiático, el subcontinente Indio y otras regiones, indica que sus orígenes genéticos fueron independientes. De igual manera acontece con las alfa talasemias (sudeste asiático, el sur de China, las Filipinas, áfrica y el Mediterráneo). En Costa Rica la alfa talasemia se encuentra en raza negra, con los dos alelos (23% para el a+:(a1) y 3.9 para el ao (a2); y han sido esporádicos los casos doble heterocigotos que originan la enfermedad por Hb H (a+/ao), siempre en individuos de extracción oriental. Especial mención se hace de la B talasemia menor y de su importante diferenciación con la anemia ferropriva. Al presente se han descrito unos 8 casos de B talasemia mayor en el país, y no son infrecuentes las formas clínicas intermedias de esta talasemia con o sin Hb S. Un breve comentario hace ver algunos aspectos novedosos de la fisiopatología de la B talasemia y su tratamiento en los países en desarrollo. While for abnormal hemoglobins it is possible to use anthropological markers to establish their origins, the thalassemias have a very wide distribution in ancestral populations. Thalassemias are the world's most common monogenic disorders. The dispersion of B thalassemia in the Mediterranean region, the Middle East, the southeastern part of Asia, the Indian subcontinent and other regions, indicate that their genetic origins were independent. a thalassemia shows a similar pattern (southeastern part of Asia, southern China, Philippines, Africa and the Mediterranean). In Costa Rica thalassemia is found in the black population with two alleles (a+ (a1) 23% and ao (a2) 3.9%). Sporadic double heterozygous cases of Hb H disease (a+/ao), are from oriental population. Special reference is made of minor B thalassemia and their important differentiation with iron deficiency anemia. Eight major B thalassemia cases have been described in our country. Intermediate thalassemia cases with or without Hb S are not infrequent. A short commentary is made of the pathophysiology of B thalassemia and the treatment in developed countries.
Estructura temporal y espacial de la comunidad de peces arrecifales de la Isla San José, Golfo de California, México Seasonal and spatial structure of reef fish community in San Jose Island, Gulf of California, México
Emelio Barjau,Jesús Rodríguez-Romero,Felipe Galván,Francisco Gutiérrez
Revista de Biología Tropical , 2012,
Abstract: Para determinar la variación estacional y espacial de la comunidad de peces en ocho localidades alrededor de la Isla San José en el Golfo de California se realizo un estudio ecológico de marzo 2001 a febrero 2002. Además, se utilizaron censos visuales en 48 transectos de 100x5m (500m2). También, se detectaron dos temporadas climáticas: una fría y otra cálida, se observaron 26 608 organismos de 112 especies de 76 géneros de peces. Asimismo, se utilizo el índice de abundancia relativa para determinar las especies más importantes. Febrero fue el mes de menor diversidad y octubre el mayor. De acuerdo con el índice de valor biológico, 13 especies fueron las que obtuvieron un mayor puntaje. En los meses cálidos se presentaron las mismas especies pero en diferente orden y abundancia. Las localidades de la zona oriental de la isla, presentaron un mayor número de especies y abundancia de peces. En el análisis de componentes principales (ACP) la riqueza específica, diversidad, equidad, número de especies y abundancia total se relacionaron con los meses cálidos. Al utilizar el ACP en su forma espacial registro que la localidad Punta Colorada obtuvo una mayor correlación con el número de especies, diversidad y abundancia total. Seasonal and spatial structure of reef fish community in San Jose Island, Gulf of California, México. The Gulf of California is one of the most fish diverse areas of the Tropical Eastern Pacific Ocean. In spite of its economic value, few works have considered fish community studies for optimum management. With the aim to determine the seasonal and spatial variation of fish communities in eight locations around the San Jose Island, some ecological research was conducted from March 2001 to February 2002. For this, visual censuses were used in 48 transects of 100x5m (500m2); specific analysis such as diversity values, the relative abundance and the biological value indexes were undertaken, and a principal component analysis applied. Our results clearly showed two climatic seasons of cold and warm waters. A total number of 26 608 organisms of 112 species and 76 genera of fishes were identified. We used the relative abundance index to determine the most important species, which were: Abudefduf troschelii, Thalassoma lucasanum, Stegastes rectifraenum, Mulloidichthys dentatus, Chromis atrilobata, Lutjanus argentiventris and Scarus ghobban. February was the month with the lowest diversity with a value of 3.12bits/ind. and October was the most diverse (4.13bits/ind.). According to the biological value index (BVI) and considering the climatic seasons,
Análisis de la abundancia, dominancia y diversidad de la comunidad de peces demersales de profundidad de 90 a 540 metros en el Golfo de California, México
Acevedo-Cervantes,Alejandro; López-Martínez,Juana; Herrera-Valdivia,Eloisa; Rodríguez-Romero,Jesús;
Interciencia , 2009,
Abstract: an analysis of the demersal fish community of the eastern continental slope of the gulf of california, méxico, was performed. samples were obtained with a trawl net at 90-540m of depth by three separate research surveys. temperature-salinity diagrams showed two main water masses, one represented by the gulf of california water mass, down to a depth of 540m, and a deeper one corresponding to the sub-surface pacific water mass. depth profiles for temperature and dissolved o2 were obtained, and plots constructed from them. these profiles showed that temperature and o2 concentration decreased gradually along a smooth gradient to a minimun of 7°c and 0.1ml·l-1, respectively, at 540m deep. seventy-one species belonging to 35 families were found. average maximum and minimum overall diversity (h′) values were 2.2 and 0.8 bits/ind and the specific richness (r) index value were 3.6 and 0.2. caelorinchus scaphopsis, merluccius productus, pleuronichthys verticals, sebastes spinorbis, microlephidium verecundum, lepophidium prorates. and lophiodes spilurus were the most dominant species, based on the relative importance index. the fish community structure suggests two different communities with two groups of species, one at 90-270m deep that shows strong associations with moderate to high diversity values and specific richness, with shared dominance by numerous species, and a second community made out of typical deep water species, with low diversity and dominance featured by a few species. the data suggests that environmental conditions play an important role in the distribution and the community structure of these species.
Nuevo registro del tiburón narizón, Apristurus nasutus de Buen, 1959, (Carcharhiniformes: Scyliorhinidae) en el Golfo de California, México
Acevedo-Cervantes, Alejandro;López-Martínez, Juana;Herrera-Valdivia, Eloisa;Rodríguez-Romero, Jesús;
Hidrobiológica , 2009,
Abstract: a total of 143 organism of apristurus nasutus (de buen, 1959), were caught in a research survey at june 2007. the samples were obtained by means of a trawl net at 250 - 460 m depth, in the middle and north part of gulf of california. this finding represents the first record of apristurus nasutus in mexican waters and therefore gives it a wider range the enlargement of his distribution. the specimens caught showed a schooling behavior, most of them in a reproductive stage.
Nuevo registro del tiburón narizón, Apristurus nasutus de Buen, 1959, (Carcharhiniformes: Scyliorhinidae) en el Golfo de California, México New record of Largenose Catshark, Apristurus nasutus de Buen, 1959, (Carcharhiniformes: Scyliorhinidae) in the Gulf of California, Mexico
Alejandro Acevedo-Cervantes,Juana López-Martínez,Eloisa Herrera-Valdivia,Jesús Rodríguez-Romero
Hidrobiológica , 2009,
Abstract: Se recolectaron 143 ejemplares de tiburón narizón Apristurus nasutus (de Buen, 1959), durante un crucero de prospección en junio de 2007. Las muestras provinieron de tres lances realizados con una red de arrastre entre los 250 y los 460 m de profundidad, en la parte media y alta del Golfo de California. El hallazgo representa el primer registro de la especie en aguas mexicanas y por consiguiente la ampliación de su ámbito de distribución. Los organismos capturados se encontraron agrupados en cardumen, la mayoría en fase reproductiva. A total of 143 organism of Apristurus nasutus (de Buen, 1959), were caught in a research survey at June 2007. The samples were obtained by means of a trawl net at 250 - 460 m depth, in the middle and north part of Gulf of California. This finding represents the first record of Apristurus nasutus in Mexican waters and therefore gives it a wider range the enlargement of his distribution. The specimens caught showed a schooling behavior, most of them in a reproductive stage.
Page 1 /359298
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.