Alimentación de los lenguados Cyclopsetta querna y Syacium latifrons en la costa de Jalisco y Colima, México

Flatfish are important components of shrimp fisheries bycatch. The purpose of this study was to analyze feeding habits of Cyclopsetta querna and Syacium latifrons, with the aim of expanding the biological knowledge of these species. Specimens were collected in seven sampling stations with shrimp trawl nets. Stomachs of 196 individuals of C. querna and 313 of S. latifrons were analyzed. The trophic spectrum of C. querna consisted of 12 food components, while 24 were recorded for S. latifrons. The main prey for C. querna were fish, while for S. latifrons it was crustaceans, such as stomatopods. A slight ontogenetic trophic variation was observed in C. querna, not so in S. latifrons; however, no differences were observed considering only the diet by sex. Diversity analyses of the food spectrum were less than 0.5 for both species. It is considered that in both species feeding is given mainly by the seasonal availability of resources and by the ability to capture prey. On the other hand, the coexistence of these species in the same area is due to the difference in the preferential consumption of prey hence reducing the competition for food.Los lenguados forman un componente importante como fauna de acompañamiento del camarón. El objetivo del presente trabajo consistió en analizar la alimentación de Cyclopseta querna y Syacium latifrons, con el fin de ampliar el conocimiento biológico de estas especies. Los ejemplares se colectaron en siete estaciones de muestreo con redes de arrastre de camarón. Se analizaron los estómagos de 196 individuos de C. querna y 313 de S. latifrons. El espectro trófico de C. querna estuvo constituido por 12 componentes alimentarios, mientras que para S. latifrons se registraron 24. Las presas principales de C. querna fueron los peces, mientras que para S. latifrons fueron los crustáceos, como por ejemplo, estomatópodos. Se observó una ligera variación ontogénica en la dieta de C. querna, no así en S. latifrons; sin embargo, en la dieta por sexos no se observaron diferencias. Los análisis de diversidad del espectro alimentario fueron menores de 0,5 para ambas especies. Se considera que en ambas especies la alimentación se da principalmente por la disponibilidad de recursos en las estaciones del año y por la capacidad de captura de presas. Por otra parte, la coexistencia de estas especies en una misma zona se da por diferencias en el consumo preferencial de sus presas al disminuir la competencia por alimento

Ten millennia of hepatitis B virus evolution

Hepatitis B virus (HBV) has been infecting humans for millennia and remains a global health problem, but its past diversity and dispersal routes are largely unknown. We generated HBV genomic data from 137 Eurasians and Native Americans dated between similar to 10,500 and similar to 400 years ago. We date the most recent common ancestor of all HBV lineages to between similar to 20,000 and 12,000 years ago, with the virus present in European and South American hunter-gatherers during the early Holocene. After the European Neolithic transition, Mesolithic HBV strains were replaced by a lineage likely disseminated by early farmers that prevailed throughout western Eurasia for similar to 4000 years, declining around the end of the 2nd millennium BCE. The only remnant of this prehistoric HBV diversity is the rare genotype G, which appears to have reemerged during the HIV pandemic.Molecular Technology and Informatics for Personalised Medicine and Healt

Ten millennia of hepatitis B virus evolution

Hepatitis B virus (HBV) has been infecting humans for millennia and remains a global health problem, but its past diversity and dispersal routes are largely unknown. We generated HBV genomic data from 137 Eurasians and Native Americans dated between ~10,500 and ~400 years ago. We date the most recent common ancestor of all HBV lineages to between ~20,000 and 12,000 years ago, with the virus present in European and South American hunter-gatherers during the early Holocene. After the European Neolithic transition, Mesolithic HBV strains were replaced by a lineage likely disseminated by early farmers that prevailed throughout western Eurasia for ~4000 years, declining around the end of the 2nd millennium BCE. The only remnant of this prehistoric HBV diversity is the rare genotype G, which appears to have reemerged during the HIV pandemic

Population structure and accompanying biota of the snail Turbo (Callopoma) funiculosus (Gastropoda: Turbinidae), on Socorro Island, Revillagigedo Archipelago, Mexico

The porcelain snail, Turbo funiculosus, is a potential fishery resource that almost has not been studied or used commercially. In March of 1992, we sampled T. funiculosus in Bahía Binners and Bahía Blanca, Socorro Island, Revillagigedo Archipelago, using 25 m2 quadrants. We found that total length varies between 3.0 and 85 mm, proportional weight between 3.0 and 228 g, and density between 6.21 and 9.87 ind/m2. The largest organisms (over 50 mm) contain 30.6 % of soft parts. Porcelain snail populations remain unexploited on Revillagedo Archipelago and could be a potential resource under an adequate management strategy

Spatial variation of the abundance of the soft-bottom fauna on the continental shelf off cjalisco and colima, mexico (spring 1995)

La distribución espacial de la abundancia de la fauna de fondos blandos en la plataforma continental de Jalisco y Colima (costa del Pacífico de México) fue investigada mediante un censo realizado con redes de arrastre para la pesca de camarón. Se tomaron muestras en siete localidades, a profundidades medias de 20, 40, 60 y 80 m en mayo y junio de 1995. Los índices de abundancia fueron expresados como número de individuos y peso total por unidad de área barrida, expresada en hectáreas. Los valores obtenidos mostraron una varianza muy alta, con intervalos de 30 a 1,952 ind/ha y 0.6 a 110.3 kg/ha para los peces y de 121 a 6,536 ind/ha y 1.0 a 64.5 kg/ha para los invertebrados. Se encontraron diferencias en los índices de abundancia medios entre localidades, pero no se pudo determinar una causa para estas diferencias. Los índices de abundancia medios variaron con la profundidad, probablemente debido a la variación de la temperatura del agua adyacente al fondo. En la profundidad de 60 m se encontró un gran número de peces pequeños, principalmente de las familias Batrachoididae, Scorpaenidae y el orden Pleuronectiformes. A 20 y 40 m se encontró un número de individuos menor pero valores más altos de peso por unidad de área, debido a la dominancia en estos niveles de especies con un peso individual medio mayor, como las de la familia Diodontidae y el orden Rajiformes. Los invertebrados presentaron tallas más uniformes en todo el gradiente de profundidad y fueron más abundantes a 60 m. Las especies de la familia Portunidae fueron dominantes. Spatial distribution of the abundance of the soft-bottom fauna on the continental shelf off Jalisco and Colima (Pacific coast of Mexico) was investigated through a survey with shrimp trawl nets. Samples were taken at seven sites with mean depths of 20, 40, 60 and 80 m during May and June 1995. Abundance indexes are given as number of individuals and total weight per unit of area swept in hectares. The values obtained showed a very high variance, with ranges from 30 to 1.952 ind/ha and 0.6 to 110.3 kg/ha for the fishes. and from 121 to 6,536 ind/ha and 1.0 to 64.5 kg/ha for the invertebrates. Differences in mean abundance indexes between sites were found, but the cause for these was not determined. Mean abundance indexes changed with depth, probably due to changes in the temperature of the water near the bottom. At the depth of 60 m, a high number of small fishes, mainly of the families Batrachoididae, Scorpaenidae and the order Pleuronectiformes, were found. At 20 and 40 m. a lesser mean number of individuals but a higher total weight per unit area were found as a consequence of the predominance in these levels of species with a higher mean individual weight, such as those of the family Diodontidae and the order Rajiformes. Invertebrates had a more uniform size throughout the depth gradient and were more abundant at the depth of 60 m. The species of the family Portunidae were dominant

Educación, paz y derechos humanos: ensayos y experiencias

Los trabajos compilados se organizan en tres apartados. El primero, "La educación para la paz y los derechos humanos", integra trabajos sobre el discurso individualista y los derechos de los excluidos, las tareas pendientes de investigación, y las intuiciones y certezas sobre la educación para la paz. El segundo apartado, "La educación para la paz y los derechos humanos en la educación formal", presenta algunas experiencias, como son la yugoslava, la de una escuela wixarika, y la de una escuela en el Estado de México. El tercer apartado, "La educación para la paz y los derechos humanos en la educación no formal", integra experiencias desarrolladas en grupos de derechos humanos, de teatro popular, de la cultura nahua y organismos de la sociedad civil