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121.
Supervised field trials were conducted at the research farms of four agricultural universities located at different agro-climatic zones of India to find out the harvest time residues of flubendiamide and its des-iodo metabolite on pigeon pea (Cajanus cajan) during the year 2006-2007. Two spray applications of flubendiamide 20 WDG at 50 g (T(1)) and 100 g (T(2)) a.i./ha were given to the crop at 15-days interval. The foliage samples at different time intervals were drawn at only one location, however, the harvest time samples of pigeon pea grain, shell, and straw were drawn at all the four locations. The residues were estimated by HPLC coupled with UV-VIS variable detector. No residues of flubendiamide and its des-iodo metabolite were found at harvest of the crop at or above the LOQ level of 0.05 μg/g. On the basis of the data generated, a pre-harvest interval (PHI) of 28 days has been recommended and the flubendiamide 20 WDG has been registered for use on pigeon pea by Central Insecticide Board and Registration Committee, Ministry of Agriculture, Government of India and the MRL has been fixed by Ministry of Health and Family Welfare, Government of India under Prevention of Food and Adulteration as 0.05 μg/g on pigeon pea grains.  相似文献   
122.
123.
Five woody plants species (i.e. Terminalia arjuna, Prosopis juliflora, Populus alba, Eucalyptus tereticornis and Dendrocalamus strictus) were selected for phytoremediation and grow on tannery sludge dumps of Common Effluent Treatment Plant (CETP), Unnao (Uttar Pradesh), India. Concentration of toxic metals were observed high in the raw tannery sludge i.e. Fe-1667 > Cr-628 > Zn-592 > Pb-427 > Cu-354 > Mn-210 > Cd-125 > Ni-76 mg kg−1 dw, respectively. Besides, physico-chemical properties of the raw sludge represented the toxic nature to human health and may pose numerous risks to local environment. The growth performances of woody plants were assessed in terms of various growth parameters such as height, diameter at breast height (DBH) and canopy area of plants. All the plant species have the capabilities to accumulate substantial amount of toxic metals in their tissues during the remediation. The ratio of accumulated metals in the plants were found in the order Fe > Cr > Mn > Pb > Zn > Cu > Cd > Ni and significant changes in physico-chemical parameters of tannery sludge were observed after treatment. All the woody plants indicated high bioconcentration factor for different metals in the order Fe > Cr > Mn > Ni > Cd > Pb > Zn > Cu. After one year of phytoremediation, the level of toxic metals were removed from tannery sludge up to Cr (70.22)%, Ni (59.21)%, Cd (58.4)%, Fe (49.75)%, Mn (30.95)%, Zn (22.80)%, Cu (20.46)% and Pb (14.05)%, respectively.  相似文献   
124.
High demand for outdoor recreation and increasing diversity in outdoor recreation participants have imposed a great challenge on the National Park Service (NPS), which is tasked with the mission to provide open access for quality outdoor recreation and maintain the ecological integrity of the park system. In addition to management practices of education and restrictions, building a sense of natural resource stewardship among visitors may also facilitate the NPS ability to react to this challenge. The purpose of our study is to suggest a segmentation approach that is built on the social marketing framework and aimed at influencing visitor behaviors to support conservation. Attitude toward natural resource management, an indicator of natural resource stewardship, is used as the basis for segmenting park visitors. This segmentation approach is examined based on a survey of 987 visitors to the Padre Island National Seashore (PAIS) in Texas in 2003. Results of the K-means cluster analysis identify three visitor segments: Conservation-Oriented, Development-Oriented, and Status Quo visitors. This segmentation solution is verified using respondents’ socio-demographic backgrounds, use patterns, experience preferences, and attitudes toward a proposed regulation. Suggestions are provided to better target the three visitor segments and facilitate a sense of natural resource stewardship among them.  相似文献   
125.
Srivastava SK 《Disasters》2009,33(1):58-81
The right mix of policy, institutional arrangements and use of technology provides the framework for a country's approach to disaster mitigation. Worldwide, there has been a shift away from a strictly 'top-down' approach relying on government alone, to a combination of 'top-down' and 'bottom-up' approaches. The aim is to enhance the indigenous coping mechanisms of vulnerable communities; draw on their cooperative spirit and energy; and empower them through appropriate information and contextual knowledge to mitigate natural disasters. In light of this, the paper examines India's use of space technology in its disaster management efforts. Poverty alleviation and disaster management are almost inseparable in many parts of the country, as vulnerability to natural disasters is closely aligned with poverty. Addressing these issues together requires integrated knowledge systems. The paper examines how knowledge inputs from space technology have strengthened the national resolve to combat natural disasters in conjunction with alleviating rural poverty.  相似文献   
126.

Background

In this paper, batch removal of hexavalent chromium from aqueous solutions by Araucaria heterophylla leaves was investigated. The batch experiments were conducted to study the adsorption of metal species and effect of different pH, contact time, metal concentration, biosorbent concentration, and adsorption capacity.

Method

Freundlich and Langmuir??s isotherm model were used to describe the adsorption behavior, and the experimental results fitted Freundlich model well.

Results

The adsorption efficiency observed for all chromium concentrations, i.e., 1, 3, 5, and 10?mg/L was 100% and the equilibrium was achieved in 30?min for 1 and 3?mg/L, whereas for 5 and 10?mg/L, it was less than 60?min. FTIR spectra was taken to identify functional groups involved in the biosorption.

Conclusion

Thus, Araucaria leaves can be considered as one of the cheap and efficient biosorbent for toxic hexavalent chromium removal from natural or wastewaters.  相似文献   
127.
128.
Scientific concern exists about the toxic effect of dichlorodiphenyldichloroethylene (p, p′-DDE) and lindane on male infertility, and the mechanism underlying male reproductive toxicity of this pesticide remains unanswered. We investigated not only the possible association between the chlorinated pesticide levels and semen quality in nonoccupationally exposed men, but also the probable mode of action using mitochondrial membrane potential (MMP), reactive oxygen species (ROS), lipid peroxidation (LPO), and sperm chromatin structure assay (SCSA). A study in 278 men (21–40 years old) who visited Obstetrics and Gynecology Department, KGMU, Lucknow, for semen analysis was conducted. We performed semen analysis according to the WHO guidelines, while p, p′-DDE and lindane analysis was done by the GLC and LPO by the spectrophotometer, and the sperm mitochondrial status, ROS, and SCSA with the flow cytometer. The questionnaire data showed no significant difference in the demographic characteristics between the two groups, i.e., trying to conceive >1 year and proven fertility. However, a significant difference in the concentration of p, p′-DDE and lindane was observed between the groups. When the subjects were divided among four categories by quartile of exposure, the subjects in the highest quartile showed low sperm motility as compared to the subjects in the lowest quartile. Pearson’s correlation showed a significant negative correlation between semen p, p′-DDE, lindane level, and sperm quality and positive association with the number of cells with depolarized mitochondria, elevation in ROS production and LPO, and DNA fragmentation index (DFI). The findings are suggestive that these toxicants might cause a decline in semen quality, and these effects might be ROS, LPO, and mitochondrial dysfunction mediated.  相似文献   
129.
Bioremediation of textile dyestuffs under solid-state fermentation (SSF) using industrial wastes as substrate pose an economically feasible, promising, and eco-friendly alternative. The purpose of this study was to adsorb Red M5B dye, a sample of dyes mixture and a real textile effluent on distillery industry waste-yeast biomass (DIW-YB) and its further bioremediation using Bacillus cereus EBT1 under SSF. Textile dyestuffs were allowed to adsorb on DIW-YB. DIW-YB adsorbed dyestuffs were decolorized under SSF by using B. cereus. Enzyme analysis was carried out to ensure decolorization of Red M5B. Metabolites after dye degradation were analyzed using UV–Vis spectroscopy, FTIR, HPLC, and GC-MS. DIW-YB showed adsorption of Red M5B, dyes mixture and a textile wastewater sample up to 87, 70, and 81 %, respectively. DIW-YB adsorbed Red M5B was decolorized up to 98 % by B. cereus in 36 h. Whereas B. cereus could effectively reduce American Dye Manufacture Institute value from DIW-YB adsorbed mixture of textile dyes and textile wastewater up to 70 and 100 %, respectively. Induction of extracellular enzymes such as laccase and azoreductase suggests their involvement in dye degradation. Repeated utilization of DIW-YB showed consistent adsorption and ADMI removal from textile wastewater up to seven cycles. HPLC and FTIR analysis confirms the biodegradation of Red M5B. GC-MS analysis revealed the formation of new metabolites. B. cereus has potential to bioremediate adsorbed textile dyestuffs on DIW-YB. B. cereus along with DIW-YB showed enhanced decolorization performance in tray bioreactor which suggests its potential for large-scale treatment procedures.  相似文献   
130.
Bajpai A  Shukla P  Dixit BS  Banerji R 《Chemosphere》2007,67(7):1403-1407
In this study, organochlorine insecticides (OCPs), DDT metabolites and HCH isomers were quantified in mustard, groundnut and sunflower oils collected from different regions of India. The maximum level of 222.0 ng g(-1) and minimum level of 0.2 ng g(-1) of SigmaDDT were detected in mustard oil from Deoria and Varanasi while those of SigmaHCH i.e., 1500 ng g(-1) and 8.0 ng g(-1) in mustard oil from Deoria and Kanpur, respectively. However, the maximum total concentration of alpha-, beta- and gamma-HCH was in mustard oil, whereas maximum delta-HCH was in groundnut oil. However, the maximum percentage of p,p'-DDT was in mustard oil while maximum p,p'-DDE was in groundnut oil. The study calls for periodical monitoring to ensure safe supply of edible oils to consumers.  相似文献   
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