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41.
In their natural environment, plants are often attacked simultaneously by many insect species. The specificity of induced plant responses that is reported after single herbivore attacks may be compromised under double herbivory and this may influence later arriving herbivores. The present study focuses on the dynamics of induced plant responses induced by single and double herbivory, and their effects on successive herbivores. Morphological (leaf length, area and trichome density) and chemical changes (leaf alkenyl and indole glucosinolates) in Brassica juncea were evaluated 4, 10, 14 and 20 days after damage by the specialist Plutella xylostella alone, or together with the generalist Spodoptera litura. To assess the biological effect of the plant’s responses, the preference and performance of both herbivores on previously induced plants were measured. We found that alkenyl glucosinolates were induced 20 days after damage by P. xylostella alone, whereas their levels were elevated as early as 4 days after double herbivory. Trichome density was increased in both treatments, but was higher after double herbivory. Interestingly, there was an overall decrease in indole glucosinolates and an increase in leaf size due to damage by P. xylostella, which was not observed during double damage. S. litura preferred and performed better on undamaged plants, whereas P. xylostella preferred damaged plants and performed better on plants damaged 14 and 10 days after single and double herbivory, respectively. Our results suggest that temporal studies involving single versus multiple attacker situations are necessary to comprehend the role of induced plant responses in plant–herbivore interactions.  相似文献   
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Studies were conducted on population dynamics of Metaphire posthuma, Lampito mauritii and Dichogaster bolaui in cultivated pedoecosystem of desert region of Rajasthan. The populations of aclitellate and clitellate M. posthuma, L. mauritii and D. bolaui were maximum in rainy season and minimum in summer season. The abundant population of these worms were found during the months of July to October. The species M. posthuma breed throughout the year except in extreme summer but L. mauritii breed twice in a year in the field. However, D. bolaui breed once in a year. Among these earthworm species D. bolaui with relative density of 44.2% was the most dominant species in cultivated land while L. mauritii and M. posthuma contributed 33.3% and 22.5% of density, respectively. The total population of earthworms showed significant positive correlation with different soil nutrients.  相似文献   
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Sustainability is one of the most critical issues facing manufacturers today. The industries must develop new and innovative approaches to ensure sustainability in economic, environmental and social aspects. The operational excellence strategies such as Lean and Agile manufacturing can be applied in the industries that add value to the product by eliminating waste and quickly respond to dynamic changes in demand. This paper presents a framework that builds and assesses the sustainability of the manufacturing system with combined lean and agile concepts. Analytical Hierarchy Process and Analytical Network Process are identified as suitable methodologies to analyze the model. The model is validated in an Ayurveda Pharmaceutical industry to identify the most important factors of lean and agile manufacturing that build and enable the sustainability dimensions such as Economic, Environmental, Social, Technological and Ethical. The results show that the industry focuses more on economic aspects of sustainability followed by social, environmental, ethics and technological dimensions of sustainability in the case of a lean perspective. For an agile perspective, the weightage is more for social dimension followed by ethics, economic, technological and environmental dimensions of sustainability.  相似文献   
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Phthalates are plasticizers and are concerned environmental endocrine-disrupting compounds. Due to their extensive usage in plastic manufacturing and personal care products as well as the potential to leach out from these products, phthalates have been detected in various aquatic environments including drinking water, groundwater, surface water, and wastewater. The primary source of their environmental occurrence is the discharge of phthalate-laden wastewater and sludge. This review focuses on recent knowledge on the occurrence of phthalate in different aquatic environments and their fate in conventional and advanced wastewater treatment processes. This review also summarizes recent advances in biological removal and degradation mechanisms of phthalates, identifies knowledge gaps, and suggests future research directions.  相似文献   
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The present investigation determined the effects of epibrassinolide (EBL) on the levels of indole-3-acetic acid (IAA), abscisic acid (ABA), and polyamine (PA) and antioxidant potential of 7-d old Raphanus sativus L. cv. ‘Pusa chetki’ seedlings grown under Cr (VI) metal stress. Reduced titers of free (0.767 μg g−1 FW) and bound (0.545 μg g−1 FW) IAA in Cr (VI) stressed seedlings were observed over untreated control. Supplementations of EBL to Cr (VI) stressed seedlings were able to enhance both free (2.14-5.68 μg g−1 FW) and bound IAA (2.45-7.78 μg g−1 FW) concentrations in comparison to Cr (VI) metal treatment alone. Significant rise in free (13.49 μg g−1 FW) and bound (12.17 μg g−1 FW) ABA contents were noticed for Cr (VI) stressed seedlings when compared to untreated control. No significant increase in ABA contents were recorded for Cr (VI) stressed seedlings upon supplementation with EBL over Cr (VI) treatment alone. A significant increase in Put (18.40 μg g−1 FW) and Cad (9.08 μg g−1 FW) contents were found for 10−9 M EBL plus Cr (VI) metal treatments when compared to Cr (VI) treatment alone. Spermidine (Spd) contents were found to decline significantly for EBL treatment alone or when supplemented with Cr (VI) treatments over untreated controls and Cr (VI) treatment alone. Antioxidant levels were found to enhance, with glutathione (57.98 mg g−1 FW), proline (4.97 mg g−1 FW), glycinebetaine (39.01 μmol mL−1), ascorbic acid (3.17 mg g−1 FW) and phytochelatins (65.69 μmol g−1 FW) contents noted for EBL supplemented to Cr (VI) metal solution over Cr (VI) treatment alone. Reduced activities of guaiacol peroxidase (0.391 U mg−1 protein) and catalase (0.221 U mg−1 protein) and enhanced activities of glutathione reductase (7.14 U mg−1 protein), superoxide dismutase (15.20 U mg−1 protein) and ascorbate peroxidase (4.31 U mg−1 protein) were observed in seedlings treated with EBL plus Cr (VI) over Cr metal treatment alone. Reduced MDA (2.55 μmol g−1 FW) and H2O2 (33.24 μmol g−1 FW) contents were recorded for 10−9 M EBL supplemented to Cr (VI) stress over Cr (VI) treatment alone. Enhancement in free radical scavenging potential as indicated by higher values of 1,1-diphenylpicrylhydrazyl, deoxyribose and reducing power activity assays, and increased levels of phenols and soluble sugars also showed significant influence of EBL in alleviating Cr (VI) stress in radish seedlings.  相似文献   
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A sharp decline in the water level in Jaipur city and its hinterland region in NW India has been observed during the last decades. Such a drop can be correlated with a widening gap between groundwater draft and recharge resulting from poor and erratic rainfall and over-exploitation of groundwater resources. The city has undergone uncontrolled urban expansion complete with a multifold rise in the population, which now stands at more than 3.3 million. Drying up of the surface water bodies has further led to a total dependence on groundwater resources to meet the rising domestic and industrial demand for water. There are about 1,000 bore wells drilled by Governmental agencies and an estimated 11,000 privately owned ones. The water is generally alkaline carbonate–bicarbonate type. We evaluated water quality for the period between 1993 and 2001 and observed notable deterioration that we attribute to inadequate recharge and a change in the potential water-bearing zones from alluvium to granite–gneiss bedrocks, caused by a drop in the water table. In addition, we also attribute the problem of high nitrate in groundwater in densely populated parts of Jaipur city to improper sewage disposal.  相似文献   
50.
The biodegradation behavior of PCL film with high molecular weight (80,000 Da) in presence of bacterium Alcaligenes faecalis and the analysis of degraded polymer film have been carried out. Thin Films of PCL were prepared by means of solution casting method and the bacterial degradation behavior was carried in basal medium, in presence of bacteria with time variation after UV treatment. It was observed that after UV treatment the degradation of polymer film was increased and the degradation rate followed a three steps degradation mechanism. The degraded polymer film was analyzed by means of Differential Scanning Calorimeter (DSC), Thermo Gravimetric Analyzer (TGA) and Fourier Transform Infrared Spectroscope (FTIR). DSC results revealed that at the initial stages of the degradation up to 15–20 days, the bacterium preferentially degrades the amorphous parts of the polymer film over the crystalline zone. Thermo gravimetric analysis highlighted the low temperature stability of degraded films with extent of degradation. FTIR results showed the chain scission mechanism of the polymer chains and also supported the preferential degradation of amorphous phase over crystalline phase in the initial stages of the degradation.  相似文献   
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