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Shagufta YASMEEN Nintu MANDAL Anupam DAS Pritam GANGULY Sanjay KUMAR Rajiv RAKSHIT 《土壤圈》2024,34(3):664-675
Soil ecosystem is experiencing stresses due to climate change, and soil inhabitants try to demonstrate their inherent resistance and resilience against those stresses. Application of nanomaterials as agricultural inputs could bring shifts in resistance and resilience patterns of soil microbes and associated enzymes, especially under short-term heat stress. With this background, the impacts of multi-walled carbon nanotube (MWCNT) on the resistance and resilience of soil biological indicators were evaluated. An incubation experiment was conducted with varied MWCNT concentrations (0, 50, 100, 250, and 500 mg kg-1 soil) for 90 d after 24-h heat stress at 48 ±2 ℃ to assess the impacts of MWCNT on soil enzyme activities and microbial populations vis-à-vis their resistance and resilience indices under short-term exposure to heat stress. Enzyme activities were reduced after exposure to heat stress. Resistance indices of enzyme activities were enhanced by MWCNT application on day 1 after heat stress, whereas there was no recovery of enzyme activities after 90-d incubation. Like soil enzyme activities, resistance index values of soil microbial populations followed the similar trend and were improved by MWCNT application. Multi-walled carbon nanotube has the potential to improve resistance indices of soil enzyme activities and microbial populations under heat stress, although they could not recover to their original state during periodical incubation after heat stress. This study helps to understand the relative changes of biological indicators under MWCNT and their ability to withstand heat stress. 相似文献
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Pritam Singh 《Forest Pathology》1989,19(3):129-143
This article describes the most important biotechnological research in major tree diseases of Canadian forests and discusses the role of biotechnology in the management of forest diseases. A brief information on Canada's forest resources and the damage caused by these diseases is also included. 相似文献
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Pritam Singh 《Forest Pathology》1980,10(7):420-431
Inoculation of five softwood provenances have revealed that they vary considerably with regard to their percent infection, percent mortality, severity of disease symptoms and progress of infection. Sitka spruce was the most susceptible species and served as a better substrate for further development of mycelium and rhizomorphs as compared to Norway and black spruces and Scots pine. The fungus always entered through uninjured surface of root collar and/or roots, the latter with more than 2 mm diameter. There was a conspicuous reduction m the total and annual growth in height in A. mellea-infected seedlings. 相似文献
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Venkatathalam Dinakaran Vinod Kumar Dumka Bibhuti Ranjan Ramalingam Balaje Pritam Kaur Sidhu 《Tropical animal health and production》2013,45(7):1509-1512
Disposition following single intravenous injection (2 mg/kg) and pharmacodynamics of cefquinome were investigated in buffalo calves 6–8 months of age. Drug levels in plasma were estimated by high-performance liquid chromatography. The plasma concentration–time profile following intravenous administration was best described by a two-compartment open model. Rapid distribution of cefquinome was evident from the short distribution half-life (t ½α ?=?0.36?±?0.01 h), and small apparent volume of distribution (Vdarea?=?0.31?±?0.008 L/kg) indicated limited drug distribution in buffalo calves. The values of area under plasma concentration–time curve, elimination half-life (t ½β ), total body clearance (ClB), and mean residence time were 32.9?±?0.56 μg·h/mL, 3.56?±?0.05 h, 60.9?±?1.09 mL/h/kg, and 4.24?±?0.09 h, respectively. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration of cefquinome were 0.035–0.07 and 0.05–0.09 μg/mL, respectively. A single intravenous injection of 2 mg/kg may be effective to maintain the MIC up to 12 h in buffalo calves against the pathogens for which cefquinome is indicated. 相似文献
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Utilization of fly ash, a byproduct of coal combustion in thermal power plants, is a sustainable use of waste for power generation. Discarding fly ash as waste in landfills/ash ponds may not only be regarded as a loss of valuable land and essential nutrients, but also pose a significant health hazard due to fine air-borne particles and leaching of heavy metals. The presence of essential macro- and micronutrients and its porosity make fly ash an excellent soil amendment for plant growth as an organic nitrogen (N) and carbon (C) supplementation. As harmful heavy metals make fly ash unsafe for agronomy, bioenergy crop plantation and energy generation from different thermochemical conversions of the biomass would be an ideal method for coal fly ash utilization through which carbon-neutral fuel can be generated from fossil fuel, thus reducing climate change impact. This review summarizes the development of bioenergy plantation and silviculture at fly ash dumpsites with an integrated phyto-bio-rhizo-mycoremediation approach and assesses utilization of the valuable biomass for thermal energy, electricity, and biofuel generation with inclusion of a SWOT analysis (a strategic technique typically used to help identify the strength, weakness, opportunities, and threat). Bioenergy crop production through integrated phytomanagement can generate billions of dollars of wealth from waste and provides a sustainable solution for fly ash management, with environmental, economic, and social benefits. 相似文献
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Yarns and fabrics are subjected to a low level of stresses or strains of repetitive nature in processing and actual use which
leads to breakage, permanent deformation, bagging and loss of useful life of the product. The ability of the spun yarns and
fabrics to withstand such stresses depends upon their structural integrity. A structurally rigid yarn (i.e. yarns in which
fibres are tightly bound) would behave more like an elastic solid and consume more energy during deformation as the constituent
fibres have to be deformed. Once the strain is released, the recovered energy will also be more. On the other hand if the
structural integrity of the same yarn is poor, fibres would easily slip during deformation and would consume much less energy.
The recoverable energy also will be much less. The present investigation reports on the structural integrity of friction spun
yarns in terms of energy loss or decay by employing cyclic extension test. It has been observed that friction spun yarns in
which the core is immediately wrapped by long and strong polyester fibre layer make the structure strongest as polyester is
expected to form tight wrappings. The decay in deformation energies during extension cycling depends upon sheath structure
i.e. its composition and location of constituent fibres in sheath layers. With increase in core fibre %, the decay has been
found to increase. However, the decay values discriminate more between core% differences than between sheath fibre layer arrangements. 相似文献