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Early in 1992, Bangladesh experienced an influx of Burmese refugees, reaching a total of 263,000 by May. As the health and nutritional status of the refugee population was reportedly poor, a need was felt to collect dependable data through epidemiological surveillance, on which interventions could be based. The nutritional and health status of children was dramatically poor in all camps surveyed and a deterioration was expected in the coming monsoon. Several problem areas could be identified. Based on these findings it was possible to undertake appropriate action and to avert threatening calamities. Epidemiological surveillance is an important monitoring tool to provide reliable data on the health and nutritional status of refugee populations and to help the organizations involved to prioritize and evaluate their actions.  相似文献   
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The degradative characteristics of butachlor (N-Butoxymethyl-2-chloro-2′,6′-diethyla- cetanilide) were studied under controlled laboratory conditions in clay loam alluvial (AL) soil (Typic udifluvent) and coastal saline (CS) soil (Typic endoaquept) from rice cultivated fields. The application rates included field rate (FR), 2-times FR (2FR) and 10-times FR (10FR). The incubation study was carried out at 30°C with and without decomposed cow manure (DCM) at 60% of maximum water holding capacity (WHC) and waterlogged soil condition. The half-life values depended on the soil types and initial concentrations of butachlor. Butachlor degraded faster in AL soil and in soil amended with DCM under waterlogged condition. Microbial degradation is the major avenue of butachlor degradation from soils.  相似文献   
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A laboratory study was conducted to monitor the effect of pencycuron [1-(4-chlorobenzyl)-1-cyclopentyl-3-phenylurea] on microbial parameters of alluvial (AL) soil (Typic udifluvent) and coastal saline (CS) soil (Typic endoaquept) under waterlogged condition. Pencycuron at field rate (FR), 2FR and 10FR affected the microbial biomass C (MBC), soil ergosterol content and fluorescein diacetate hydrolyzing activity (FDHA) differentially. The DCM amendment did not seem to have any counteractive effect on the toxicity of pencycuron on the microbial variables. The change in microbial metabolic quotient (qCO2) and microbial respiration quotient (QR), indicated pencycuron induced disturbance at 10FR. Present study revealed that the metabolically activated microbial population was more suppressed compared to the dormant population.  相似文献   
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In this paper we describe a theoretical approach for decentralized data management in sentinel community nutritional surveillance systems for timely warning and intervention, by using customized computer programs. By making the data available at lower levels first, the decentralized data management system builds the institutional capacity at regional, level and allows rapid and appropriate action by decision-makers. In addition, it facilitates the flow of information and strengthens the involvement of field staff. Reports from field experiences should further demonstrate the feasibility, efficacy, costs and benefits of customized data management computer programs.  相似文献   
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Thatch development in intensively managed turf sites may cause environmental concerns for greater sorption or leaching of applied chemicals in terrestrial ecosystems. To determine the adsorption potential of Carbaryl (1-Napthyl N-methylcarbamate), 2,4-D (2,4-dichloro-phenoxyacetic acid), and Triclopyr (3,5,6-trichloro-2-pyridinyloxyacetic acid) in turf ecosystems, composite thatch and underlying soil samples from three- and six-year-old stands of cool-season Southshore creeping bentgrass (Agrostis palustris Huds.) and warm-season Meyer zoysiagrass (Zoysia japonica Steud.) were collected. The samples were processed and analyzed for total organic carbon (COrg); extractable (CExt), humic (CHA) and fulvic acid (CFA); anthrone reactive nonhumic carbon (ARC) fractions; and CHA and CFA associated iron (Fe) contents. Pesticide adsorption capacity (K f ) and intensity (1/n), organic carbon partition coefficient (K OC ) and Gibbs free energy change (Δ G) were calculated for thatch materials and the underlying soils using a modified batch/flow technique. Both bentgrass (BT) and zoysiagrass thatch (ZT) contained a greater concentration of CExt, CFA, CHA, and ARC than the respective soils (BS and ZS). The CExt, CFA, CHA, and ARC concentration was higher in BT compared with ZT. The BT contained a greater concentration of bound Fe in both CFA and CHA fractions than in BS, whereas ZT had more bound Fe in CHA fraction than in ZS. On average, the BT had a greater concentration of bound Fe in CExt, CFA, and CHA fractions than in the ZT. Among the pesticides, Carbaryl had higher K f and 1/n values than 2,4-D and Triclopyr for both thatch and soil. Although the K OC and Δ G values of Carbaryl were higher in both BT and ZT than in the underlying soils, the K OC and Δ G values of 2,4-D were significantly higher in BS and ZS than in the overlying thatch materials. The 2,4-D and Triclopyr had higher leaching indices (LI) than Carbaryl for both BT and ZT materials than the respective soils. The Carbaryl, however, had a higher LI for soils than for thatch materials. Averaged across thatch materials and soils, COrg accounted for 96, 85, and 84% variations in Carbaryl, 2,4-D, and Triclopyr adsorption, respectively. Among the COrg fractions, lignin followed by CFA and CHA accounted for greater adsorption of pesticides, especially Carbaryl. The concentration of CHA and CFA bound Fe did not correlate with K f and 1/n values of pesticides.  相似文献   
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This study uses an energy flow approach to investigate the ecological sustainability of Greek agriculture. The approach is based on the analysis of ratios of energy output and energy input over a long period of time. Structural changes in land use in Greek agriculture were observed over the period 1961–98. There was an increasing trend in consumption of energy input in Greek agriculture throughout the period 1961 to 1998 as a result of diffusion of capital intensive technology. High growth in the production of energy output of cereals and vegetables was observed during the same period. The total energy output flow had a sharp increasing trend during 1961 to 1991, thereafter it declined slightly until 1998. The ratio analysis showed that the Greek agricultural system is ecologically sustainable as the energy output exceeded the amount of conventional energy required to produce it.  相似文献   
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