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Search Results: 1 - 10 of 173244 matches for " Sergio Hernández-Vázquez "
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Sustainable performance of the tourist industry in the state of baja california sur, mexico
Herrera-Ulloa,ángel F; Lluch-Cota,Salvador; Ramírez-Aguirre,Hernán; Hernández-Vázquez,Sergio; Ortega-Rubio,Alfredo;
Interciencia , 2003,
Abstract: the measurement of sustainable development is a goal for better performance of any externality producer, and indicators are one way to evaluate the implementation of practical policy decisions. the tourism industry, like many others, is an important source of income for many groups, but is also a serious potential source of environmental problems. adoption of the sustainable tourism concept is a possible way to approach these problems. to measure the historical behaviour of the tourism industry in the state of baja california sur, mexico we built a sustainable development tourism index based on multivariable analysis of a 34-indicator data set. the analysis covers the period 1990 to 2000. we found a positive trend in the index, derived from 27 indicators of sustainability and an additional 7 strategic tourist indicators. so far, baja california sur has been able to absorb the migration and growth, mainly in los cabos area, and the index suggested that the environment is apparently not seriously affected yet. however, bcs society must carefully watch the growth of tourism in subsequent years to avoid negative impacts on nature and residents. the proposed index is a performance parameter for measuring sustainable development in tourism not only in mexico, but also in other countries with an adequate data base of sustainability indicators.
Peces de la fauna de acompa?amiento en la pesca industrial de camarón en el Golfo de California, México
López-Martínez,Juana; Herrera-Valdivia,Eloisa; Rodríguez-Romero,Jesús; Hernández-Vázquez,Sergio;
Revista de Biología Tropical , 2010,
Abstract: bycatch fish species from shrimp industrial fishery in the gulf of california, mexico. the shrimp fishery in the gulf of california is one the most important activities of revenue and employment for communities. nevertheless, this fishery has also created a large bycatch problem, principally fish. to asses this issue, a group of observers were placed on board the industrial shrimp fleet and evaluated the eastern side of the gulf during 2004 and 2005. studies consisted on 20kg samples of the capture for each trawl, and made possible a systematic list of species for this geographic area. fish represented 70% of the capture. a total of 51 101 fish were collected, belonging to two classes, 20 orders, 65 families, 127 genera, and 241 species. the order perciformes was the most diverse with 31 families, 78 genera, and 158 species. the best represented families by number of species were: sciaenidae (34) and paralichthyidae (18) and haemulidae and carangidae (16 each). the best represented genera in number of species were symphurus (nine) and diplectrum and cynoscion (six); other important genera were larimus and porichthys with five species each. the best represented species in number were syacium ovale, pseudupeneus grandisquamis, haemulopsis nitidos, diplectrum pacificum, synodus scituliceps, balistes polylepis, eucinostomus currani, eucinostomus gracilis, porichthys analis, chloroscombrus orqueta, selene peruviana, orthopristis reddingi, etropus crossotus, scorpaena sonorae and urobatis halleri. the number of recorded species is notably high, compared with demersal fauna of other areas of the mexican pacific, such as gulf of tehuantepec (178), nayarit, michoacán, guerrero (174, 120 and 166), jalisco and colima (161 species), and those of the western coast of the baja california peninsula (220 species). rev. biol. trop. 58 (3): 925-942. epub 2010 september 01.
Composición taxonómica y relaciones zoogeográficas de los peces demersales de la costa occidental de Baja California Sur, México
Jesús Rodríguez-Romero,Deivis S Palacios-Salgado,Juana López-Martínez,Sergio Hernández-Vázquez
Revista de Biología Tropical , 2008,
Abstract: Se presenta la composición sistemática de peces demersales de la costa occidental de Baja California Sur, límite de distribución norte de la ictiofauna del Pacífico Oriental Tropical. Se realizaron cuatro cruceros oceanográficos durante oto o de 2004 a marzo de 2006. Este listado incluye 220 especies, 132 géneros y 73 familias. El 26.3% corresponde a especies de amplia distribución desde la Provincia de San Diego a la Provincia Panámica y el 21.7% son especies restringidas a la región del Pacífico Oriental Tropical. Seis especies representan nuevos registros para la zona o ampliación de su ámbito de distribución. Las familias mejor representadas en número de especies fueron Paralichthyidae y Scorpaenidae, con 16 especies cada una. El género mejor representado fue Sebastes con 9 especies. Se presentan los nombres comunes, intervalo de tallas y el estatus de cada especie dentro de la comunidad Taxonomic composition and zoogeographic relations of demersal in the western coast of Baja California Sur, Mexico. The composition of demersal fish along the western coast of the State of Baja California Sur, México, including the limit of the northern distribution of the ichthyofauna of the eastern tropical Pacific, is presented. The survey was carried out on four oceanographic cruises between autumn 2004 and March 2006. Of 220 species in 132 genera and 73 families, 26.3% are species of wide distribution from San Diego County, USA to Panama and 21.7% are species restricted to the eastern tropical Pacific. Six species are new findings for the area or range expansions. The families with the most species are Paralichthyidae and Scorpaenidae, each with 16 species. The most frequent genus was Sebastes, with nine species. We present a table with common Spanish names, size range and status of each species inside the community. Rev. Biol. Trop. 56 (4): 1765-1783. Epub 2008 December 12.
Peces de la fauna de acompa amiento en la pesca industrial de camarón en el Golfo de California, México
Juana López-Martínez,Eloisa Herrera-Valdivia,Jesús Rodríguez-Romero,Sergio Hernández-Vázquez
Revista de Biología Tropical , 2010,
Abstract: Composición taxonómica de peces integrantes de la fauna de acompa amiento de la pesca industrial de camarón del Golfo de California, México. La pesquería de camarón es la más importante en el Golfo de California y también la más problemática con respecto a las capturas incidentales en México. Dentro de la fauna de acompa amiento del camarón (FAC), el grupo de mayor abundancia son los peces. Se presenta listado sistemático de las especies de peces presentes en la FAC de la pesquería industrial de camarón en la costa oriental del Golfo de California. Durante 2004-2005 se implementó un sistema de observadores a bordo de la flota camaronera de Guaymas, Sonora, que recolectaron muestras de 20kg de la captura. Los peces representaron 70% de las capturas en número. Se recolectó un total de 51 101 ejemplares de peces, pertenecientes a dos clases, 20 órdenes, 65 familias, 127 géneros y 241 especies. El orden Perciformes fue el más diverso (31 familias, 78 géneros y 158 especies). Las familias mejor representadas en número de especies fueron: Sciaenidae y Paralichthyidae con 34 y 18 especies, Haemulidae y Carangidae aportaron 16 especies. Los géneros mejor representados fueron Symphurus con nueve y Diplectrum y Cynoscion con seis especies, otros géneros importantes fueron Larimus y Porichthys con cinco especies. El número de especies registrado es alto, comparado con la fauna demersal de otras áreas del Pacífico Mexicano. Esta alta riqueza de especies se puede atribuir a los sistemas de corrientes, surgencias, remolinos, topografía y batimetría únicas, que en conjunto originan un ecosistema dinámico con un amplio régimen térmico y una gran variedad de hábitats. Los resultados aqui presentados ponen de manifiesto que esta región del Golfo de California presenta una gran riqueza de especies, lo que abre diversas expectativas desde el punto de vista ecológico, pesquero, alimenticio y de manejo. Bycatch fish species from shrimp industrial fishery in the Gulf of California, Mexico. The shrimp fishery in the Gulf of California is one the most important activities of revenue and employment for communities. Nevertheless, this fishery has also created a large bycatch problem, principally fish. To asses this issue, a group of observers were placed on board the industrial shrimp fleet and evaluated the Eastern side of the Gulf during 2004 and 2005. Studies consisted on 20kg samples of the capture for each trawl, and made possible a systematic list of species for this geographic area. Fish represented 70% of the capture. A total of 51 101 fish were collected, belonging to two
Composición taxonómica y relaciones zoogeográficas de los peces demersales de la costa occidental de Baja California Sur, México
Rodríguez-Romero,Jesús; Palacios-Salgado,Deivis S; López-Martínez,Juana; Hernández-Vázquez,Sergio; Ponce-Díaz,Germán;
Revista de Biología Tropical , 2008,
Abstract: taxonomic composition and zoogeographic relations of demersal in the western coast of baja california sur, mexico. the composition of demersal fish along the western coast of the state of baja california sur, méxico, including the limit of the northern distribution of the ichthyofauna of the eastern tropical pacific, is presented. the survey was carried out on four oceanographic cruises between autumn 2004 and march 2006. of 220 species in 132 genera and 73 families, 26.3% are species of wide distribution from san diego county, usa to panama and 21.7% are species restricted to the eastern tropical pacific. six species are new findings for the area or range expansions. the families with the most species are paralichthyidae and scorpaenidae, each with 16 species. the most frequent genus was sebastes, with nine species. we present a table with common spanish names, size range and status of each species inside the community. rev. biol. trop. 56 (4): 1765-1783. epub 2008 december 12.
Coastal waterbirds of El Chorro and Majahuas, Jalisco, México, during the non-breeding season, 1995-1996
Hernández-Vázquez,Salvador; Mellink,Eric;
Revista de Biología Tropical , 2001,
Abstract: we studied how waterbirds used two small estuaries during the non-breeding season of 1995-1996. these estuaries, el chorro and majahuas, were located in the middle of a large span of non-wetland habitat along the pacific coast of méxico. whereas el chorro was basically a large and open waterbody, majahuas was a long and narrow corridor flanked by mangroves. the two estuaries had 77 species throughout our study, but shared only 58, due to differences in their habitat. seabirds comprised 66% of all the birds; grebes, ducks and rails 16%; shorebirds 12% and herons and egrets 5%. during late winter and early spring a very reduced number of migratory species accounted for the dominance of seabirds. sterna hirundo and phalacrocorax brasilianus accounted for 40 and 33%, respectively, of all the seabirds. opening or closure of the estuary mouth at el chorro affected the bird communities at both sites, by exposing or inundating a large mudflat in that estuary. overall, however, time of the year was more important in the composition of the bird assemblages. both estuaries should be considered as a single unit.
Coastal waterbirds of El Chorro and Majahuas, Jalisco, México, during the non-breeding season, 1995-1996
Salvador Hernández-Vázquez,Eric Mellink
Revista de Biología Tropical , 2001,
Abstract: We studied how waterbirds used two small estuaries during the non-breeding season of 1995-1996. These estuaries, El Chorro and Majahuas, were located in the middle of a large span of non-wetland habitat along the Pacific coast of México. Whereas El Chorro was basically a large and open waterbody, Majahuas was a long and narrow corridor flanked by mangroves. The two estuaries had 77 species throughout our study, but shared only 58, due to differences in their habitat. Seabirds comprised 66% of all the birds; grebes, ducks and rails 16%; shorebirds 12% and herons and egrets 5%. During late winter and early spring a very reduced number of migratory species accounted for the dominance of seabirds. Sterna hirundo and Phalacrocorax brasilianus accounted for 40 and 33%, respectively, of all the seabirds. Opening or closure of the estuary mouth at El Chorro affected the bird communities at both sites, by exposing or inundating a large mudflat in that estuary. Overall, however, time of the year was more important in the composition of the bird assemblages. Both estuaries should be considered as a single unit. Durante la estación no reproductiva de 1995-1996 estudiamos las aves acuáticas de los estuarios El Chorro y Majahuas, Jalisco, México. El Chorro es un cuerpo de agua más abierto, mientras que Majahuas está formado por canales rodeados por manglares. Registramos 77 especies de aves. Las aves marinas comprendieron el 66%, los patos y similares el 16%, las aves playeras el 12% y las garzas el 5%. Sterna hirundo y Phalacrocorax brasilianus representaron el 40 y 33%, respectivamente, del total de aves marinas. El que la bocabarra de El Chorro estuviera abierta o cerrada influyó en la concentración de aves en los dos esteros, debido a la exposición o inundación de áreas lodosas y arenosas. A pesar de las diferencias entre los dos estuarios, la época del a o fue más importante en la composición de las comunidades de aves. Ambos esteros deben considerarse como una sola entidad ecológica.
Solvent- and Catalyst-Free Microwave-Assisted Decarboxylation of Malonic Acid Derivatives  [PDF]
Fanny Araceli Cabrera-Rivera, Luis Gabriel Hernández-Vázquez, Patricia Flores-Sánchez, Maria Durán-Galván, Jaime Escalante
Green and Sustainable Chemistry (GSC) , 2017, DOI: 10.4236/gsc.2017.74021
Abstract: It has been found that microwave assisted decarboxylation of malonic acid derivatives can be achieved under solvent-free and catalyst free conditions. This new method produces the corresponding carboxylic acid in a pure manner and with a high yield in a very short reaction time: 3 - 10 min. In general terms, the condition under which this reaction is carried out accelerates the decarboxylation significantly of a series of disubstituted malonic acid derivatives, and makes this new process efficient, easy and environmentally friendly.
Evaluación de las creencias sobre el tratamiento: validez y fiabilidad de la versión espa ola del Beliefs about Medicines Questionnaire
Marina Beléndez-Vázquez,Antonio Hernández-Mijares,Robert Horne,John Weinman
International Journal of Clinical and Health Psychology , 2007,
Abstract: El Beliefs about Medicines Questionnaire (BMQ) se dise ó para evaluar las creencias sobre la medicación y consta de dos secciones, BMQ-General y BMQEspecífico. El objetivo de este estudio instrumental fue evaluar la estructura factorial y fiabilidad de la versión espa ola del BMQ. En el estudio del BMQ-Específico participaron 156 pacientes, 97 diabéticos tratados con insulina y 59 pacientes con medicación antihipertensiva. Las propiedades del BMQ-General se analizaron con las muestras de pacientes crónicos y en un grupo de 256 jóvenes universitarios. Se obtuvo un patrón bifactorial para ambas escalas de la versión espa ola del BMQ, al igual que la versión original. Se comprobó su validez para discriminar entre pacientes con distintas modalidades de tratamiento. Los pacientes tratados con insulina obtuvieron puntuaciones significativamente mayores en la escala Necesidad en comparación con los sujetos hipertensos. La consistencia interna de las escalas del BMQ resultó adecuada en las tres muestras de participantes. La versión espa ola del BMQ es un instrumento válido y fiable para evaluar las creencias sobre la medicación, aunque es preciso realizar otros estudios con diferentes grupos de pacientes y tipos de tratamiento, así como estudiar las relaciones entre el BMQ y la adherencia al tratamiento.
Variability of rainfall from tropical cyclones in northwestern México and its relation to SOI and PDO
DíAZ, S. C;SALINAS-ZAVALA, C. A;HERNáNDEZ-VáZQUEZ, S;
Atmósfera , 2008,
Abstract: tropical cyclones during september affect the semi-arid northwestern region of méxico with a relatively high frequency, bringing much-needed precipitation. this study provided a better understanding of tropical cyclone inter-annual variability, their relationships with other atmospheric-oceanic phenomena, and their inter-decadal occurrences. daily rain data from 534 meteorological stations were analyzed and used to calculate the percentage of the annual precipitation related to tropical cyclones of the eastern north pacific ocean affecting the region from 1949 to 2002. using interpolation techniques, the stations were grouped in 1o x 1° areas, and the area structure of the tropical cyclone influence was obtained using empirical orthogonal function (eof) variable analysis to identify five regions. representative inter-annual variation series from each region were analyzed to identify changes in the influence of tropical cyclones as part of the annual precipitation. a gradient of tropical cyclone influence was found declining from south to north, mainly in the peninsula area. a regime shift in 1976 is coincident with a shift trend in series from areas with larger tropical cyclones influence. the southern oscillation index (soi) driving is stronger for the northern part of the region, while the southern part has stronger pacific decadal oscillation (pdo) influence.
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