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111.
The paper presents a methodology that guided several ethnoentomological research projects and goes on to examine and compare the results from two independent research locations in Asia. The first location is in the Philippines, a Green Revolution area that has been heavily impacted by extension messages and insecticide use. The second location is in Nepal which has a traditional subsistence orientation and has remained widely unaffected by agricultural modernization. The paper emphasizes the differences and similarities of the results from the two sites and discusses the role of the methodology and methods used in capturing ethnoentomological knowledge, particularly with regard to insect pests in rice. The results of both investigations share the importance of agronomic criteria among farmers in insect classification and sorting criteria, thus highlighting the relevance of functional criteria. Farmers at both research sites have difficulties in identifying the lifecycles of insects. We discuss the issues of tradition and change in farmer entomological knowledge and providing support to the knowledge base of farmers though programs like IPM-Farmer Field Schools as opposed to broad-based recommendations for crop pest management.Article type: MS-ENVI-SI ETHNOSCI MS04 Contribution to Environment, Development & Sustainability, special issue ‘Bridging the gap between natural resources and their human management for the future using ethnoscience’.  相似文献   
112.
The St. Johns River Water Management District (SJRWMD) has developed a minimum flows and levels (MFLs) method that has been applied to rivers, lakes, wetlands, and springs. The method is primarily focused on ecological protection to ensure systems meet or exceed minimum eco-hydrologic requirements. MFLs are not calculated from past hydrology. Information from elevation transects is typically used to determine MFLs. Multiple MFLs define a minimum hydrologic regime to ensure that high, intermediate, and low hydrologic conditions are protected. MFLs are often expressed as statistics of long-term hydrology incorporating magnitude (flow and/or level), duration (days), and return interval (years). Timing and rates of change, the two other critical hydrologic components, should be sufficiently natural. The method is an event-based, non-equilibrium approach. The method is used in a regulatory water management framework to ensure that surface and groundwater withdrawals do not cause significant harm to the water resources and ecology of the above referenced system types. MFLs are implemented with hydrologic water budget models that simulate long-term system hydrology. The method enables a priori hydrologic assessments that include the cumulative effects of water withdrawals. Additionally, the method can be used to evaluate management options for systems that may be over-allocated or for eco-hydrologic restoration projects. The method can be used outside of the SJRWMD. However, the goals, criteria, and indicators of protection used to establish MFLs are system-dependent. Development of regionally important criteria and indicators of protection may be required prior to use elsewhere.  相似文献   
113.
At present glass fibre reinforced plastic (GRP) waste recycling worldwide is very limited due to its intrinsic thermoset properties, lack of characterisation data and non availability of viable recycling and recovery routes. In the present study, efforts were made to recycle GRP waste powder and fibre in concrete and cement composites and assess its quality to comply with the British standards for use in construction applications. Results revealed that the mean compressive strength of concrete composites using 5%–50% GRP waste powder under water curing varied from 37 N/mm2 to 19 N/mm2. Increase in the concentration of GRP waste decreased the compressive strength. However, increase in curing duration (14–180 days) resulted in improving the compressive strength of concrete with 5% GRP application to 45.75 N/mm2. Moreover, the density of concrete with 50% GRP waste was reduced by about 12% as compared to the control sample. The bending strength in terms of modules of rupture (MOR) of 12 mm thickness cement composites developed using 5% GRP waste fibre attained 16.5 N/mm2. The findings of this work pave the way for further GRP waste recycling in precast construction products for use in various applications.  相似文献   
114.
An electron capture chromatographic method of detecting nitro-ethylene and 1-nitro-lpropene was developed and applied to ambient air samples, photolyzed propene/nitrogen dioxide mixtures and auto exhaust. No trace of either compound was found in ambient air or in the photolyzed mixtures. The detection limit was estimated to be 1 ppb. A single sample of auto exhaust showed several small peaks which, if attributed to nitroolefin, would amount to insignificant traces  相似文献   
115.
Abstract

Sheep metabolized a single oral dose of 2‐chloro‐N‐isopro‐pylacetanilide (propachlor) to four urinary metabolites. These were 2‐(S‐cysteinyl)‐N‐isopropylacetanilide and 2‐[S‐(N‐acetyl) cysteinyl]‐N‐isopropylacetanilide and the glucuronide conjugates of 4'‐hydroxy‐N‐isopropyl‐2‐methylsulfonylacetanilide and N‐(1‐hydroxyisopropyl)‐2‐methylsulfonylacetanilide. Residues (ppb equivalents of propachlor) from [14C]‐propachlor in the milk from a goat given daily oral doses (1.3 mg of propachlor three times daily for 15 days) plateaued at about 2 to 4 ppb equivalents of propachlor. In goat tissue, residues ranged from 1 ppb (fat) to 20 ppb (liver). Fecal and tissue metabolites were not identified.  相似文献   
116.
Abstract

Waste distribution and compaction at the working face of municipal waste landfills releases mercury vapor (Hg0) to the atmosphere, as does the flaring of landfill gas. Waste storage and processing before its addition to the landfill also has the potential to release Hg0 to the air if it is initially present or formed by chemical reduction of HgII to Hg0 within collected waste. We measured the release of Hg vapor to the atmosphere during dumpster and transfer station activities and waste storage before landfilling at a municipal landfill operation in central Florida. We also quantified the potential contribution of specific Hg-bearing wastes, including mercury (Hg) thermometers and fluorescent bulbs, and searched for primary Hg sources in sorted wastes at three different landfills. Surprisingly large fluxes were estimated for Hg losses at transfer facilities (~100 mg/hr) and from dumpsters in the field (~30 mg/hr for 1,000 dumpsters), suggesting that Hg emissions occurring before landfilling may constitute a significant fraction of the total emission from the disposal/landfill cycle and a need for more measurements on these sources. Reducing conditions of landfill burial were obviously not needed to generate strong Hg0 signals, indicating that much of the Hg was already present in a metallic (Hg0) form. Attempts to identify specific Hg sources in excavated and sorted waste indicated few readily identifiable sources; because of effective mixing and diffusion of Hg0, the entire waste mass acts as a source. Broken fluorescent bulbs and thermometers in dumpsters emitted Hg0 at 10 to >100 μg/hr and continued to act as near constant sources for several days.  相似文献   
117.
Decamethylcyclopentasiloxane, commonly known as D5 (cyclopentasiloxane) has a wide application of use across a multitude of personal care product categories. The relative volatility of D5 is one of the key properties attributed to this substance that provide for the derived performance benefits from the use of this raw material in personal care formulations. On this basis, rapid evaporative loss following use of many products comprising D5 is expected following typical use application and corresponding wear time.  相似文献   
118.
Abstract

Rats metabolized single oral doses of O,O‐diethy1–0‐(3,5,6‐trichloro‐2‐pyridyl‐2,6‐14C) phosphorothioate to at least six radiolabeled urinary metabolites. The urine contained about 90 percent of the dose. Three of these metabolites were identified as the glucuronide of 3,5,6‐trichloro‐2‐pyridinol (80% the urinary l4C), a glycoside of 3,5,6‐trichloro‐2‐pyridinol (4%), and 3,5,6‐trichloro‐2‐pyridinol (12%).  相似文献   
119.
Although atrazine has been banned in the European Union since 2007 it still persists in soil from where it can enter the food chain. Milk-producing animals accumulate atrazine from contaminated feed and water and since large quantities of milk and milk products are consumed its quality should be constantly monitored. The objective of this investigation was to develop a simple tube ELISA procedure suitable for use in non-specialised laboratories and in the field. A polyclonal antibody raised in sheep and the hapten-gelatine conjugate was immobilised onto polystyrene tubes. This enables the colour produced to be read on a basic spectrophotometer. Milk samples were collected from three farms in different regions of Poland and diluted before immunoassay was performed. Samples were extracted with hexane-acetone for HPLC analysis. The amount of fat in the milk samples interferes with the dose response so it essential that the standards are prepared in the same samples matrix. A good correlation between 1% and 2% was found between the two methods in the analysis of real samples. However the ELISA procedure was more sensitive that the HPLC method since atrazine was detected in some samples by the ELISA but was not confirmed by the HPLC method. The study demonstrated that the simple antigen-coated tube assay provides a cost effective and valuable screening test that can be easily modified for direct use as a screening tool in the field.  相似文献   
120.
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