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Zooplankton in Arabian Sea, India
Get PDFThe abundance of zooplankton in marine environment has direct influence on fishery resources and it is influenced by environmental parameters such as circulatory movements (eddies) and vertical turbulent mixing. The important role of plankton including both microzooplankton and macrozooplankton in supporting life in the sea was recognized in the past, but the study related to ecology of these organisms has still recently formed as intractable aspect in marine ecosystem. Life in the sea has been broadly classified into three groups, viz., the plankton, the nekton and the benthos. The majority of the faunal assemblages of the plankton consists of zooplankton. Among the various levels of production in the sea the secondary production, i.e., production of zooplankton, attains significance as it serves as a link between primary production and tertiary production. The zooplankton chiefly consumes the primary producers and forms the major food source for tertiary producers. Zooplankton plays an important role in coral reef ecosystem. They serve as food for corals, and a variety of other invertebrates and reef fishes. From the fishery point of view, zooplankton forms food of/ from important batfishes belonging to the families Clupeidae, Caesionidae and Apogonidae. Some fishes are exclusively zooplankton feeders and therefore their abundance is directly linked to the presence of zooplankton
Value addition activities and challenges of African yam bean (Sphenostylis stenocarpa) farmers in Enugu State, Nigeria
Get PDFThe study examined the value addition practices and challenges of African yam bean (Sphenostylis stenocarpa) farmers in Enugu State of Nigeria. Multistage sampling technique was adopted in selecting a total of seventy two (72) respondents used for the study. Results revealed that all (100%) of the respondents processed African yam bean through sun drying, husking/hulling and preservation/storage while about 88.9% of the respondents processed the crop through frying/baking while 87.5% and 70.8% of the respondents indicated they were involved in winnowing and grinding. Lack of basic physical infrastructure (M=2.39), lack/poor technology on processing, preservation etc (2.35), difficulty in accessing loan (M=2.28) and lack of technology/innovation on production of the crop (M=2.28) were among the constraining factors to value addition in African yam bean. It is recommended that policy makers should work towards providing the necessary technology and basic infrastructure to farmers in order to increase their productivity, income and commercialization of this underutilized but important crop. Research efforts are also required to improve its agronomic characteristics and promote its cultivation
FTIR characterization ans chemo-mechanical distinction of reted kenaf fibres
Get PDFInadequate information on the binding characteristics of kenaf biomass at the molecular level has adversely affected the modifications of its cellulose-hemicellulose-lignin structure. This study was undertaken to assess the characteristic features and chemo-mechanical properties of kenaf fibres retted under three different media namely: tank, stream and ribbon. Fourier transform infra-red (FTIR) spectra analysis as well as the ASTM standard for tensile tests were applied. The results showed that the broad bands occurred at the range of 3312- 3420 cm−1 for all the retted fibres were due to the presence of hydroxyl (–OH) group while the peaks were obtained at 1635.76, 1635.34, and 1730.69 cm−1 for stream, tank and ribbon retted fibres respectively. However, tank retted fibres had the most broad band intensity at 3419.78cm-1 while ribbon fibres had the highest absorption peak of 1730.69cm-1 corresponding to C=O stretching of the acetyl group in hemi-cellulose. Stream retted Kenaf fibres had the highest tensile strength followed by the tank retted fibres while ribbon fibres had the least. Furthermore, there was no significant difference between stream and tank retted Kenaf fibres in terms of tensile modulus and this was significantly higher than that of ribbon fibre. The α-cellulose content of stream retted fibres was slightly higher than that of ribbon fibres while tank retted fibres had the least. From the results, tank retted Kenaf fibre was ranked as ‘the best fibre’ with the most intensive broad bands and least in lignin and hemi-cellulose content which were regarded as the impurities, gummy and waxy materials, responsible for an easy deformation of the fibre cellular networks
Impacto de composición familiar en los niveles de pobreza de Perú
Get PDFThe present study uses data from the latest version of the National Households’Survey, an annual representative survey carried out in Peru, to determine whether family composition and structure can predict household members falling below the poverty line, or protect them from doing so. The results obtained from a multiple regression study indicate that families consisting of parents who live in a free domestic partnership with underage children, households with large numbers of members, and poor quality employment of the head of the family are all factors that can increase the possibility of being poor. On the other hand, the variables related to lower probabilities of poverty are: having two or more income earners in the household, living in an urban area, having a better education, and a female head of the household; all these factors protect families and reduce the effects of povertyEl presente estudio utiliza los datos de la última versión de la Encuesta Nacional de Hogares (Enaho) —una encuesta anual y representativa de la población de Perú— para determinar en qué medida la composición y estructura familiar puede predecir o evitar que los miembros del hogar sobrepasen la línea de pobreza. Los resultados obtenidos, a través de un modelo de regresión logística, indican que las familias constituidas por padres que mantienen una unión libre o convivencia con hijos menores de edad, los hogares con número extenso de miembros y la mala calidad de empleo del jefe de familia son aspectos que incrementan la posibilidad de que el hogar sea pobre. Por otro lado, las variables consideradas y relacionadas a menores probabilidades de escenarios de pobreza son: contar con dos o más perceptores de ingresos en el hogar, vivir en un área urbana, tener un mejor grado de instrucción, tenencia de activos y la jefatura femenina del hogar; todos ellos aspectos que tienen la capacidad de mitigar los efectos de la pobrez
Investigando a la élite económica: Lecciones y desafíos a partir del caso de Chile
Get PDFThis paper lays out the lessons and challenges that stem from the last 25 years of research on Chilean elites. Particular emphasis is given to works that study economic elites. Based on 12 in-depth interviews with some of the main researchers in the field, the paper offers a systematic analysis of the grounds on which these researchers justify their use of the concept of elites to refer to the upper strata of Chilean society, in detriment of other concepts such as ruling class or aristocracy. The paper also analyzes the approaches and strategies used by them, their samples and methods, and the difficulties they find in the fieldwork, contributing to a reflexive analysis on the ways of researching the contemporary elites. Finally, challenges and avenues for future research in this area are proposed.Este artículo estudia los aprendizajes y desafíos que se desprenden de la investigación empírica sobre élites en Chile en las últimas dos décadas, con énfasis en la élite económica. Utilizando doce entrevistas semiestructuradas a expertos que han investigado a este grupo en Chile y una operacionalización específica para diferenciar los criterios y prioridades de cada investigador, los resultados sistematizan los fundamentos para optar por el concepto de élite por sobre otros (como clase dominante o aristocracia), las estrategias para definir el universo y muestra, y las dificultades de este tipo de estudios. Los resultados contribuyen al análisis reflexivo sobre las formas en que las élites contemporáneas son estudiadas, a lo que se añaden también desafíos pendientes y líneas de investigación a futuro que vinculen esta área con otros fenómenos de relevancia para la vida social
La apicultura del valle central chileno como práctica de conservación socialmente inclusiva en un contexto de escasez hídrica socialmente construida
Get PDFThrough an ethnographic approach that complements conversations, tours and surveys of productive characterization is that the present study aims to approach the domestic beekeeping in the valley of Colliguay, Quilpué, fifth region of Chile. This is an activity that emerges as a result of deep transformations detonated by the neoliberalization of nature in general and water in particular. That is why it seeks to contextualize the situation of water scarcity that displaced livestock and put in place the bees. All of this through a political ecology lens. It is discussed how to achieve an anthropological reading of the ecological scenarios that denaturalize metabolic fractures in an area with a threatened presence of native forest. It is discovered that the outsider is the material and symbolic responsible of an increase in water stress and a key element in the social relations of confrontation of the valley. It is then related how bees have diverted the attention of their human counterparts to the affection and care of the forest that allows them to live, thus reinforcing the idea of a socially inclusive conservation.Mediante un enfoque etnográfico que complementa conversaciones, recorridos y encuestas productivas, este estudio se adentra en la apicultura doméstica realizada en el valle de Colliguay, comuna de Quilpué, Quinta región de Chile. Esta es una actividad que emerge como resultado de profundas transformaciones detonadas por la neoliberalización de la naturaleza en general y del agua en particular. Por ello es que se busca contextualizar la situación de escasez hídrica que desplazó al ganado y puso en su lugar a las abejas mediante una lectura desde la ecología política. Se discute así sobre cómo realizar una lectura antropológica de los escenarios ecológicos que desnaturalicen las fracturas metabólicas que sufre una zona con amenazada presencia de bosque nativo. Se descubre que es el afuerino el responsable material y simbólico de un incremento en el estrés hídrico y pieza clave en las relaciones sociales de confrontación del valle. Se relata luego cómo las abejas han fomentado el interés y afecto hacia el bosque, reforzando así la idea de una conservación socialmente inclusiva
Anestesia inhalatoria en el equino: Características y consideraciones al momento de su uso
Get PDFLos anestésicos son fármacos potentes que no tienen un tiempo definido de uso, sin embargo, debido a las características predecibles de recuperación anestésica que poseen, y pese a que generan cambios drásticos en la función cardiovascular y respiratoria, son indispensables en medicina equina. Para lograr una anestesia balanceada combinamos el uso de diferentes fármacos endovenosos con un anestésico inhalatorio. Cual fármaco utilizar dependerá tanto del estado de salud general, como del tipo de procedimiento al que será sometido el paciente. Es por esto, que antes de someter a un paciente a anestesia, éste debe ser examinado cuidadosamente para así caracterizar su estado general. Para ello existe el sistema de clasificación ASA que permite determinar las consideraciones anestésicas y así poder disminuir los riesgos que conlleva dicho procedimiento. Es fundamental que mientras el paciente este anestesiado sea monitoreado constantemente, para así asegurar y controlar que tanto la función fisiológica, como la profundidad anestésica sean las adecuadas, lo que a su vez permitirá actuar a tiempo frente a las diversas complicaciones que se pudiesen presentar. La morbilidad y mortalidad en la anestesia equina es considerablemente mayor que en otras especies domésticas
