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481.
482.
Host plant resistance (HPR) to insects is an effective, economical, and environment friendly method of pest control. The most attractive feature of HPR is that farmers virtually do not need any skill in application techniques, and there is no cash investment by the resource poor farmers. Considerable progress has been made in identification and development of crop cultivars with resistance to the major pests in different crops. There is a need to transfer resistance genes into high-yielding cultivars with adaptation to different agro-ecosystems. Resistance to insects should form one of the criteria to release varieties and hybrids for cultivation by the farmers. Genes from the wild relatives of crops, and novel genes, such as those from Bacillus thuringiensis can also be deployed in different crops to make HPR an effective weapon to minimize the losses due to insect pests. HPR will not only cause a major reduction in pesticide use and slowdown the rate of development of resistance to insecticides in insect populations, but also lead to increased activity of beneficial organisms and reduction in pesticide residues in food and food products.  相似文献   
483.
A new trematode, collected in 1971 from Ratnagiri, India, is described as Follicovitellosum indicum sp. nov. A new subfamily, Follicovitellotrematinae is created within the family Zoogonidae Odhner, 1911, to receive the new genus Follicovitellosum, with its genotype F. indicum. The new species is characterized by the follicularized nature of its ovary; the ovarian follicles are posttesticular. The vitellarium is further divided into several follicles which are largely in the pre-ovarian zone, but post-acetabular and posttesticular in location.  相似文献   
484.
The maximum likelihood (ML) method for regression analyzes of censored data (below detection limit) for nonlinear models is presented. The proposed ML method has been translated into an equivalent least squares method (ML-LS). A two stage iterative algorithm is proposed to estimate statistical parameters from the derived least squares translation. The developed algorithm is applied to a nonlinear model for prediction of ambient air CO concentration in terms of concentrations of respirable particulate matter (RSPM) and NO2. It has been shown that if censored data are ignored or estimated through simplifications such as (i) censored data are equal to detection limit, (ii) censored data are half of the difference between detection limit and lower limit (e.g., zero or background level) or (iii) censored data are equal to lower limit, this can cause significant bias in estimated parameters. The developed ML-LS method provided better estimates of parameters than any of the simplifications in censored data.  相似文献   
485.
The kinetics of ferrate(VI) (FeVIO4 2−, Fe(VI)) oxidation of an antiphlogistic drug, ibuprofen (IBP), as a function of pH (7.75–9.10) and temperature (25–45°C) were investigated to see the applicability of Fe(VI) in removing this drug from water. The rates decrease with an increase in pH and the rates are related to protonation of ferrate(VI). The rates increase with an increase in temperature. The E a of the reaction at pH 9.10 was calculated as 65.4±6.4 kJ mol−1. The rate constant of the HFeO4 with ibuprofen is lower than with the sulphur drug, sulfamethoxazole. The use of Fe(VI) to remove ibuprofen is briefly discussed.  相似文献   
486.
Life cycle assessment (LCA) provides a concept, framework, and method to identify and evaluate the environmental burdens of products and processes. An ongoing concern of companies trying to implement LCA is the value of LCA in supporting actual decisions versus the resources and time needed to conduct a “full” LCA. In response to these concerns, there has been a lot of activity surrounding the “streamlining” of LCA to keep it more manageable yet provide useful and acceptably accurate results. This article explores the concept of streamlining, discusses where and how streamlining decisions can be made in an LCA, and presents issues related to conducting more streamlined LCAs. Due to the wide variety of purposes and scenarios in which LCAs are conducted, it is difficult to devise a one-size-fits-all method for streamlining. Instead, we have focused on presenting the streamlining options in the context of major decision points that are common to most LCAs.  相似文献   
487.
The global agenda of sustainable development (SD) will get a major boost from the successful implementation of the Sustainable Development Goals (SDGs) in developing countries. This requires effective planning and understanding of the SDGs at the national level and developing sound SDG indicators that account for country priorities. Currently, there is no formal SDG indicator set in India, but the process for it is underway. This paper has attempted to propose a unique technique for identifying the most representative indicator set for SD measurement in India based on the SDGs. Considering the needs and preferences of the country, a three‐stage process is proposed to develop the priority indicator set. The application of the approach has been presented for SDG 7, which relates to energy. This is supported with a background on India's SD progress. The proposed technique is simple yet effective, and can be easily replicated by other developing countries.  相似文献   
488.
489.
This study was conducted in the summer season (May, 2007). The fluoride concentration along with other physico-chemical parameters in ground water samples was determined in Marks Nagar of Unnao district, Uttar Pradesh (India), since it is the only source of drinking water for the villagers. The fluoride concentration in the water varied from 0.8 to 13.9 mgl−1 with a mean of 4.02 mgl−1. The correlation analysis revealed that fluoride had a positive correlation with pH, CO3, HCO3, and sodium adsorption ratio (SAR), whereas a negative correlation with Ca and Mg was found. A soil profile was also dug in the area to assess depth-wise fluoride content in the soil. The soil samples and underneath calcium carbonate (CaCO3) concretion were analyzed for fluoride content. The percent of soluble fluoride to total fluoride in the soil varied from 25.15 to 4.76% down the soil profile. The soluble fluoride was found to decrease with the increase in the clay content in the soil. The total leachable fluoride in CaCO3 concretions was found to be 6.08%. It was inferred from this study that the soil and underneath layer of CaCO3 concretions may be the potential source of fluoride contamination in the shallow drinking water sources of the area.  相似文献   
490.
The presence of dyes in water is undesirable due to the toxicological impact of their entrance into the food chain. Owing to the recalcitrant nature of dyes to biological oxidation, a tertiary treatment like adsorption is required. In the present study, unsaturated polyester resin (UPR) has been used as a sorbent in the treatment of dye-contaminated water. Different concentrations of Tropaeoline 000 containing water were treated with UPR. The preliminary investigations were carried out by batch adsorption to examine the effects of pH, adsorbate concentration, adsorbent dosage, contact time, and temperature. A plausible mechanism for the ongoing adsorption process and thermodynamic parameters have also been obtained from Langmuir and Freundlich adsorption isotherm models. Thermodynamic parameter showed that the sorption process of Tropaeoline 000 onto activated carbon (AC) and UPR were feasible, spontaneous, and endothermic under studied conditions. The estimated values for (ΔG) are ?10.48?×?103 and ?6.098?×?103 kJ mol?1 over AC and UPR at 303 K (30 °C), indicating towards a spontaneous process. The adsorption process followed pseudo-first-order model. The mass transfer property of the sorption process was studied using Lagergren pseudo-first-order kinetic models. The values of % removal and k ad for dye systems were calculated at different temperatures (303–323 K). The mechanism of the adsorption process was determined from the intraparticle diffusion model.  相似文献   
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