981 resultados para Rice, Samuel, 1775-1840.


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This paper presents the results of a study on the use of rice husk ash (RHA) for property modification of high density polyethylene (HDPE). Rice husk is a waste product of the rice processing industry. It is used widely as a fuel which results in large quantities of RHA. Here, the characterization of RHA has been done with the help of X-ray diffraction (XRD), Inductively Coupled Plasma Atomic Emission Spectroscopy (ICPAES), light scattering based particle size analysis, Fourier transform infrared spectroscopy (FTIR) and Scanning Electron Microscope (SEM). Most reports suggest that RHA when blended directly with polymers without polar groups does not improve the properties of the polymer substantially. In this study RHA is blended with HDPE in the presence of a compatibilizer. The compatibilized HDPE-RHA blend has a tensile strength about 18% higher than that of virgin HDPE. The elongation-at-break is also higher for the compatibilized blend. TGA studies reveal that uncompatibilized as well as compatibilized HDPERHA composites have excellent thermal stability. The results prove that RHA is a valuable reinforcing material for HDPE and the environmental pollution arising from RHA can be eliminated in a profitable way by this technique.

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The morphological and biochemical response of calli and seedlings of different rice cultivars were compared under acid saline conditions. Calli of both tolerant and sensitive varieties showed severe stress symptoms like browning and necrosis, but the onset of stress symptoms was delayed in Pokkali. Seedlings of Pokkali showed minimal stress symptoms in lower salinities, and curling and senescence of older leaves in higher salinities although plants revived on amelioration of stress. Seedlings of the other varieties showed severe stress symptoms even at low salinities and plant death at higher salinities. Salt stress induced accumulation of the putative osmoprotectant proline in calli and seedlings of all varieties. Proline accumulation was higher in sensitive varieties than in Pokkali. These results indicate that proline accumulation is not directly correlated with salt tolerance in rice.

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This study describes a combined empirical/modeling approach to assess the possible impact of climate variability on rice production in the Philippines. We collated climate data of the last two decades (1985-2002) as well as yield statistics of six provinces of the Philippines, selected along a North-South gradient. Data from the climate information system of NASA were used as input parameters of the model ORYZA2000 to determine potential yields and, in the next steps, the yield gaps defined as the difference between potential and actual yields. Both simulated and actual yields of irrigated rice varied strongly between years. However, no climate-driven trends were apparent and the variability in actual yields showed no correlation with climatic parameters. The observed variation in simulated yields was attributable to seasonal variations in climate (dry/wet season) and to climatic differences between provinces and agro-ecological zones. The actual yield variation between provinces was not related to differences in the climatic yield potential but rather to soil and management factors. The resulting yield gap was largest in remote and infrastructurally disfavored provinces (low external input use) with a high production potential (high solar radiation and day-night temperature differences). In turn, the yield gap was lowest in central provinces with good market access but with a relatively low climatic yield potential. We conclude that neither long-term trends nor the variability of the climate can explain current rice yield trends and that agroecological, seasonal, and management effects are over-riding any possible climatic variations. On the other hand the lack of a climate-driven trend in the present situation may be superseded by ongoing climate change in the future.

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Rice straw is used in Northeastern Thailand as an alternative to organic fertilizer for crop production. This enables farmers to reduce the use of chemical fertilizers which leads to a decrease in production costs. In spite of the beneficial effects in agricultural production, rice straw compost cannot be produced in large amounts because the burning of rice straws is a common farming practice. The decisions of farmers who use rice straw compost have been investigated by interviewing 120 households belonging to the members of an organic fertilizer user group using a household questionnaire. The study was conducted to evaluate the factors that affect the use of rice straw compost in Khon Kaen Province in Northeastern Thailand. Results of the logit model showed that the farmers’ education, number of rice straw compost trainings in which the farmer participated, lack of knowledge about technology, insufficient labour and difficulty in making rice straw compost had a significant impact on the farmer’s decision to use rice straw compost. Difficulty in making rice straw compost appeared to be the root cause because the procedure of making rice straw compost is complex and labour intensive. Repeated trainings thus, will have a positive and significant influence on farmers’ adoption of the technology. Training provides more knowledge and will presumably change the perception of the farmers towards new technologies and the awareness of positive effects of rice straw compost utilization.

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The objective of this study was to report single season effects of wood biochar (char) application coupled with N fertilization on soil chemical properties, aerobic rice growth and grain yield in a clayey Rhodic Ferralsol in the Brazilian Savannah. Char application effected an increase in soil pH, K, Ca, Mg, CEC, Mn and nitrate while decreasing Al content and potential acidity of soils. No distinct effect of char application on grain yield of aerobic rice was observed. We believe that soil properties impacted by char application were inconsequential for rice yields because neither water, low pH, nor the availability of K or P were limiting factors for rice production. Rate of char above 16 Mg ha^(−1) reduced leaf area index and total shoot dry matter by 72 days after sowing. The number of panicles infected by rice blast decreased with increasing char rate. Increased dry matter beyond the remobilization capacity of the crop, and high number of panicles infected by rice blast were the likely cause of the lower grain yield observed when more than 60 kg N ha^(−1) was applied. The optimal rate of N was 46 kg ha^(−1) and resulted in a rice grain yield above 3 Mg ha^(−1).

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Poor adaptation to climate change is a major threat to sustainable rice production in Nigeria. Determinants of appropriate climate-change adaptation strategies used by rice farmers in Southwestern Nigeria have not been fully investigated. In this study, the determinants of climate change adaptation strategies used by rice farmers in Southwestern Nigeria were investigated. Data were obtained through Focus Group Discussions (FGDs) and field survey conducted in the study areas. Data obtained were analyzed using descriptive and inferential statistical tools such as percentage and regression analysis. The major climate change adaptation strategies used by the respondents included; planting improved rice variety such as Federal Agricultural Research Oryza (FARO) (80.5 %), seeking early warning information (80.9 %), shifting planting date until the weather condition was favourable (99.1 %), and using chemical fertilizer on their farms in order to maintain soil fertility (20.5 %). The determinants of climate change adaptation strategies used by the farmers, included access to early warning information (β=43.04), access to fertilizer (β=5.78), farm plot size (β=–12.04) and access to regular water supply (β=–24.79). Climate change adaptation required provision of incentives to farmers, training on drought and flood control, and the use of improved technology to obtain higher yield.

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The impact of two crop planting methods and of the application of cyanobacterial inoculants on plant growth, yield, water productivity and economics of rice cultivation was evaluated with the help of a split plot designed experiment during the rainy season of 2011 in New Delhi, India. Conventional transplanting and system of rice intensification (SRI) were tested as two different planting methods and seven treatments that considered cyanobacterial inoculants and compost were applied with three repetitions each. Results revealed no significant differences in plant performance and crop yield between both planting methods. However, the application of biofilm based BGA bio-fertiliser + 2/3 N had an overall positive impact on both, plant performance (plant height, number of tillers) and crop yield (number and weight of panicles) as well as on grain and straw yield. Higher net return and a higher benefit-cost ratio were observed in rice fields under SRI planting method, whereas the application of BGA + PGPR + 2/3 N resulted in highest values. Total water productivity and irrigation water productivity was significantly higher under SRI practices (5.95 and 3.67 kg ha^(-1) mm^(-1)) compared to practices of conventional transplanting (3.36 and 2.44), meaning that using SRI method, water saving of about 34 % could be achieved and significantly less water was required to produce one kg of rice. This study could show that a combination of plant growth promoting rhizobacteria (PGPR) in conjunction with BGA and 2/3 dose of mineral N fertiliser can support crop growth performance, crop yields and reduces overall production cost, wherefore this practices should be used in the integrated nutrient management of rice fields in India.

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The rapid increase of rice imports in sub-Saharan Africa under the unstable situation in the world rice market during the 2000s has made it an important policy target for the countries in the region to increase self-sufficiency in rice in order to enhance food security. Whether domestic rice production can be competitive with imported rice is a serious question in East African countries that lie close, just across the Arabian Sea, to major rice exporting countries in South Asia. This study investigates the international competitiveness of domestic rice production in Uganda in terms of the domestic resource cost ratio. The results show that rainfed rice cultivation, which accounts for 95% of domestic rice production, does not have a comparative advantage with respect to rice imported from Pakistan, the largest supplier of imported rice to Uganda. However, the degree of non-competitiveness is not serious, and a high possibility exists for Uganda’s rainfed rice cultivation to become internationally competitive by improving yield levels by applying more modern inputs and enhancing labour productivity. Irrigated rice cultivation, though very limited in area, is competitive even under the present input-output structure when the cost of irrigation infrastructure is treated as a sunk cost. If the cost of installing irrigation infrastructure and its operation and maintenance is taken into account, the types of irrigation development that are economically feasible are not large-scale irrigation projects, but are small- and microscale projects for lowland rice cultivation and rain-water harvesting for upland rice cultivation.

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Poner de manifiesto todos aquellos aspectos que pueden ser considerados inadecuados en el funcionamiento actual de las acciones de formación y orientación profesional e integración laboral y social de personas con minusvalías, así como de la gestión de centros e instituciones que los desarrollan. Orientación y formación profesional, integración laboral y comunitaria y gestión de proyectos. Los factores analizados se dividen en cuatro bloques. 1) Orientación: diagnóstico de la personalidad, programas, actividades y recursos para el desarrollo personal, la formación y capacitación y desarrollo profesional, evaluación de programas y actividades de orientación y formación profesional. 2) Integración laboral: características del empleo, adaptación laboral, fomento, formación y mantenimiento en el empleo. 3) Integración comunitaria: necesidades económicas y de relación, redes de información y de coordinación de recursos, acceso al empleo, adaptación de viviendas, ocio y tiempo libre. 4) Gestión: marco institucional, orientación y definición de la actividad, medios utilizados, dirección institucional y de proyectos, sistema de comunicación-información, control de la actividad y valoración de resultados. En cada uno de estos factores se analizan: necesidades personales, objetivos de los proyectos planteados, procesos desarrollados, recursos empleados y nivel de resultados. Guía de evaluación de proceso de las 10 acciones modelo del programa Helios. Programas de rehabilitación de algunos centros. Aportaciones de profesionales. Se constata la necesidad de realizar un replanteamiento de los presupuestos teóricos que fundamentan los programas y una reformulación de las técnicas y actividades aplicadas para su desarrollo. Se detectan diferencias entre esfuezos y realizaciones. En general, la actividad de los centros se circunscribe primordialmente a intentar dotar a los usuarios de habilidades ocupacionales; esto provoca sesgos en la orientación y formación profesional. Por otra parte, la integración en el mundo del empleo adolece de ser un mero adiestramiento para puestos de trabajo escasamente cualificados o considerados socialmente y con un reducido entrenamiento en la interacción socio-laboral. La gestión institucional es un tanto burocrática. No se suelen valorar los factores estimados como base de cada uno de los programas. Ofrece una serie de sugerencias específicas para cada programa. Se constata la necesidad de potenciar entornos laborales más integrados como el autoempleo y el empleo apoyado. Es fundamental formar profesionales de Servicios Sociales dedicados al asesoramiento de empresas y a la dinamización del empleo apoyado. Es preciso regular las actividades de orientación y formación profesional, definiendo las actividades mínimas a realizar. La calidad de la gestión aumentaría estableciendo un sistema de planificación y evaluación coordinado que delimitase los fines institucionales e integrase las acciones de los implicados.

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Realizar un estudio cuantitativo sobre los niños expósitos del hospicio de Oviedo, desde su fundación hasta finalizar el siglo XVIII. Situación de los niños expósitos e ilegítimos en el Real Hospicio de Oviedo. Los aspectos de análisis más relevantes en este estudio son: Volumen de expósitos: distribución anual, estacional, repercusiones de crisis económicas, etc. Mortalidad: distribución anual y estacional de las muertes de niños expósitos, comparadas con otras Instituciones similares de otras provincias, causas de las muertes, diferencias en sexos. Características de las amas de cría: edad, origen social, procedencia, salarios, oblicaciones, etc.. Además de diferentes obras bibliográficas del periódo cronológico de estudio, se consultaron una serie de obras manuscritas: Archivos de la Diputación de Asturias: libros de expósitos. Juntas de Dirección del Hospicio, ordenanzas y mandatos dados por Gil de Jaza, etc. Archivo del Ayuntamiento de Oviedo. Archivo Nacional de Simancas. Frecuencias y porcentajes de las variables de estudio citadas anteriormente: número de expósitos, mortalidad, etc. Para la elaboración de estos índices se parte del vaciado de las actas de niños expósitos localizadas en la Diputación provincial. Para la representación gráfica de los datos se utilizan diagramas de barras, gráficas y mapas. En la segunda mitad del siglo XVIII abunda la construcción de centros para acoger a la población marginada. La mayoría de los expósitos acogidos en el Real Hospicio de Oviedo son hijos ilegítimos. No hay diferencias importantes entre el número de niñas y el de niños que son expuestos. El porcentaje de fallecimientos de los niños ingresados en esta Institución durante los años de estudio es del 50 por ciento. El mayor número de muertos se registra durante los seis primeros meses de ingreso y tampoco en este caso se dan diferencias relevantes en razón del sexo. Después de unos días de su ingreso en el hospicio, el expósito es puesto al cuidado de un ama exterior, que cobra por su trabajo un sueldo muy bajo, al cabo de seis años pasa nuevamente al hospicio. Esta investigación sobre el hospicio ovetense y sobre los niños en él ingresados, es considerada por su autora como una pequeña aportación a futuras investigaciones, destinadas a conocer más exahustivamente las clases marginadas de la España de la Edad Moderna.

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Estudi del sindicalisme a Espanya des dels seus orígens i fins el 1870. L’autor planteja dues qüestions: la ideologia elaborada pel sindicalisme entre 1840 i 1856, i en segon lloc alguns aspectes de les relacions entre sindicalisme i política, i l’elaboració d’un llenguatge de classes

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El fenómeno del desplazamiento interno forzado en el mundo representa una problemática de gran envergadura que impacta a aquellas personas que se ven obligadas a migrar dentro del territorio de su país huyendo de las zonas de conflictos y de las persecuciones de los actores armados, debido al contexto de violencia en el que se encuentran y del cual resultan ser las principales víctimas. Así pues, en el caso de Colombia, el desplazamiento forzado interno representa una de las principales consecuencias que ha dejado el contexto de violencia armada sufrido en el país a lo largo de las últimas décadas, lo cual ha llevado a las instancias constitucionales a pronunciarse sobre el accionar del Estado para darle solución a esta problemática. El trabajo se enfoca específicamente en la Sentencia T-025 de 2004 proferida por la Corte Constitucional donde se establece que el país atraviesa por un Estado de Cosas Inconstitucional. De manera particular, a lo largo del análisis se realiza una evaluación de la implementación, cumplimiento y alcance de la Sentencia en la Ciudad de Bogotá, durante la Administración de Samuel Moreno Rojas.

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This is one of a series of short case studies describing how academic tutors at the University of Southampton have made use of learning technologies to support their students.

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INFO2009, Coursework 2, Green ICT/IT

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La presente monografía analiza el proceso de génesis de la política pública distrital para la reintegración de excombatientes en Bogotá, así como los momentos de cambio de dicha política durante las administraciones de los alcaldes Luis Eduardo Garzón y Samuel Moreno. Para este fin, esta monografía recurre a enfoques teóricos del policy change, incluyendo el “Enfoque de Corrientes Múltiples” de John Kingdon, el modelo de formación de la agenda desarrollado por Charles Elder y Roger Cobb, y la “Teoría del Equilibrio Puntuado” de Frank Baumgartner y Bryan Jones. Con base en entrevistas semi-estructuradas a funcionarios de los programas distritales de atención a los desmovilizados y fuentes secundarias, la presente investigación describe las acciones emprendidas por las diferentes administraciones en el periodo 2003-2013 y analiza los cambios que la política experimentó en sus instrumentos de intervención. Así, las acciones iniciales que hacían énfasis en el desmovilizado y su núcleo familiar con el propósito de fortalecer el tejido social, dieron paso a acciones enfocadas principalmente en la reintegración económica de los desmovilizados. Un análisis crítico del proceso de formación de esta política pública y sus principales cambios constituye no solo una contribución empírica a la extensa literatura sobre policy change, sino que provee lecciones para futuros procesos de reintegración de excombatientes en contextos urbanos.