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排序方式: 共有149条查询结果,搜索用时 15 毫秒
31.
Céspedes CL Lemus A Salazar JR Cabrera A Sharma P 《Journal of agricultural and food chemistry》2003,51(10):2923-2929
This work presents the herbicidal and plant growth regulatory activities of tertiary bismuthines containing heterocyclic aromatic rings of the general formula (2-C(4)H(3)X)(3)Bi, where X = S (3), O (1), or NMe (2). Toxicity against Artemia salina and herbicidal activity on Lactuca sativa, Trifolium pratense, and Lolium multiflorum were tested. In addition to the effects on mitochondrial respiration obtained from roots of Phaseolus vulgaris, these compounds also demonstrated partial radical scavenging properties against 2,2-diphenyl-1-picrylhydrazyl (DPPH). The furyl substituent is the most important structural requirement for the activity measurements observed in this study. 相似文献
32.
Setchell KD Brzezinski A Brown NM Desai PB Melhem M Meredith T Zimmer-Nechimias L Wolfe B Cohen Y Blatt Y 《Journal of agricultural and food chemistry》2005,53(6):1938-1944
Pharmacokinetic studies of soybean isoflavones have shown that following oral ingestion, the two major isoflavones, daidzin and genistin, are hydrolyzed in the intestine, rapidly absorbed into the peripheral circulation, and eliminated from the body with a terminal half-life of 7-8 h. These characteristics make maintenance of steady-state plasma isoflavone concentrations difficult to attain unless there is repeated daily ingestion of foods or supplements containing isoflavones. In an attempt to sustain more constant plasma isoflavone concentrations, a new slow-release formulation of a soybean isoflavone extract was prepared by microencapsulation with a mixture of hydroxypropylcellulose and ethylcellulose to alter its dissolution characteristics. In vitro experiments confirmed slow aqueous dissolution of isoflavones from this formulation when compared with the conventional isoflavone extract. The pharmacokinetics of this slow-release isoflavone extract was studied in 10 healthy postmenopausal women after oral administration of a single capsule containing the equivalent of 22.3 mg of genistein and 7.47 mg of daidzein expressed as aglycons. A comparison of the key pharmacokinetic parameters obtained in this study with those established in extensive studies performed previously in this laboratory indicated that the mean residence time of genistein and daidzein increased 2-fold with microencapsulation. These findings are indicative of a decreased rate of absorption, consistent with the observed slow in vitro dissolution rate. These findings show that it is feasible to employ polymer matrices that slow the aqueous dissolution for preparing sustained-release formulations of soy isoflavones. Further studies to optimize such formulations are warranted. 相似文献
33.
The present paper describes a rational approach to minimum cost design of an integrated activated sludge process which includes activated sludge reactor, secondary clarifier and sludge recycle. The cost of anaerobic digestion of excess sludge produced is also considered. Procedures for optimal design of both single and multiple stage activated sludge processes, considering construction and operational costs are developed. Biomass concentration in aeration tank and return sludge are utilized as the primary independent design variables to which system performance is related for single stage process. In the multiple stage process, additional design variables (flow and volume fractions for each stage) are included in design vector. Liquid-biomass separation is based on the batch solids flux theory. The optimization problem is framed as minimization of capital and operating cost subject to the constraints determined by effluent quality criteria and process variables affecting the performance. The interior penalty function method is used. Results definitely favor the application of multiple stage process over single stage. The major factor which appears to be contributing to reduction in cost is the biological solids retention time and hence the aeration tank volume. 相似文献
34.
Volatilization of NH3 from soil is a major N-loss mechanism that reduces the efficiency of applied N fertilizers, and causes environmental pollution. Strategies are needed to reduce the loss. The influences of dicyandiamide (DCD), farmyard manure (FYM) and irrigation on NH3 volatilization from an alluvial soil in rice (Oryza sativa L.)-wheat (Triticum aestivum L.) cropping system was studied using the acid trap method. The loss of NH3 in the rice-wheat system ranged from 38.6 kg N ha-1 from the unfertilized soil to 69.0 kg N ha-1 in the treatment with urea+DCD. Substitution of 50% N provided through urea by FYM reduced NH3-N volatilization by 10% in rice and wheat as compared to the urea treatment. Application of DCD increased NH3 volatilization in wheat by 7% but in rice it had no effect. The irrigation level had no effect on NH3 volatilization in rice but fewer irrigations with fewer splits of N in wheat resulted in higher NH3 volatilization. Application of DCD and FYM with urea had similar effects on grain yield and N uptake by rice and wheat as that of the urea treatment. The study showed that integrated use of organic manure and chemical fertilizer has the potential to reduce the loss of N due to volatilization and thereby minimize environmental pollution. Nitrification inhibitors, which are reported to be useful in increasing the N-use efficiency by reducing the leaching and denitrification losses of N, however, may increase N loss due to volatilization. 相似文献
35.
Pankaj Kumar Srivastava Poonam C. Singh Manjul Gupta Arpita Sinha Aradhana Vaish Ashish Shukla Nandita Singh Sri Krishna Tewari 《植物养料与土壤学杂志》2011,174(3):420-429
The present investigation was aimed to analyze influence of earthworm culture on nutritive status, microbial population, and enzymatic activities of composts prepared by utilizing different plant wastes. Vermicomposts were prepared from different types of leaves litter of horticulture and forest plant species by modified vermicomposting process at a farm unit. Initial thermophilic decomposition of waste load using cow‐dung slurry was done in the separate beds. The culture of Eisenia fetida was used for vermicomposting in specially designed vermibeds at the farm unit. The physico‐chemical characteristics, enzyme activities (oxido‐reductases and hydrolases), and microbial population (bacteria, fungi, free‐living nitrogen‐fixing bacteria, actinomycetes, Bacillus, Pseudomonas, phosphate‐solubilizing bacteria and fungi) of vermicomposts were found significantly higher (p < 0.05) than those of control (without earthworm inoculum). The study quantified significant contributions of earthworm culture to physico‐chemical, enzymatic, and microbiological properties of vermicompost and confirmed superior fertilization potential of vermicompost for organic farming. The agronomic utility of vermicompost was assessed on yellow mustard plant in a pot experiment. Pot soil was amended with different ratios (5%, 10%, 20%) of vermicompost and normal compost (without earthworm inoculum). Effects of these amendments on the growth of Brassica comprestis L. were studied. The significant differences (p < 0.05) in the growth of plant were observed among vermicompost‐, compost‐amended soil, and control. Vermicompost increased the root and shoot lengths, numbers of branches and leaves per plant, fresh and dry weights per plant, numbers of pods and flowers, and biochemical properties of plant leaf significantly, especially in 20% amendment. These results proved better fertilization potential of vermicompost over non‐earthworm‐inoculated compost. 相似文献
36.
The study was conducted on 18 lactating Murrah buffaloes in 83.72 ± 14.75 days after calving. Group I buffaloes were not injected
with oxytocin and served as control. Buffaloes of Group II were injected with oxytocin @ 2.5 IU per 0.5 ml intramuscularly
at the hip region for a period of 1 month while Group III buffaloes received injection of oxytocin @ 5.0 IU per ml intramuscularly
at the hip region for a period of 1 month. Milk samples from three groups of buffaloes were collected after oxytocin injections
at 15 days interval on 0, 15, 30 and 45 days. Blood samples were collected in heparinized tubes at 0, 15, 30 and 45 days of
experiment from all three groups of buffaloes. There was no significant change in cisternal, alveolar and total milk yield
by exogenous oxytocin administration. Fat % in cisternal, alveolar and total milk decreased significantly (P < 0.01) by 11.8%
and 21.3% in groups II and III buffaloes, respectively. Protein % increased significantly (P < 0.01) in group III. A significant
increase was observed in somatic cell counts of milk by 5.36% and 6.22% in groups II and III, respectively as compared to
control group.
Part of MV. Sc. Thesis of the first author submitted to National Dairy Research Institute (Deemed University) 相似文献
37.
Koratigere Parameshanayka Devaraja Ranjith Kumar Ellur Pankaj Ashok K. Singh Anumanahalli Puttasawamy Abhishek Gowda Anil Sirohi 《Plant pathology》2023,72(1):179-194
The rice root-knot nematode (RRKN), Meloidogyne graminicola, is one of the major pests of the rice–wheat cropping system. Resistance against M. graminicola in rice could be most valuable in alleviating this problem. The host response of 75 Oryza genotypes was examined at three day/night temperature regimes, 29/26°C, 34/31°C and 38/35°C, in Pluronic gel as well as in soil. Out of the 75 selected rice genotypes, only Zhenshan 97 B exhibited high resistance to this set of temperature regimes, with the least number of galls/root system. At 34/31°C, more second-stage juveniles (J2s) were hatched and J2 population densities in roots of the susceptible rice genotypes increased significantly compared with those of plants grown at the 29/26°C. In resistant genotypes, only a few J2s penetrated roots and developed into mature females. The histopathological studies revealed that in susceptible rice genotypes at high-temperature regimes, the multinucleate giant cells were well developed. The results presented in this study revealed that an increase in temperature had a significant effect on the resistance of rice genotypes and resistance appeared more pronounced in genotype Zhenshan 97 B. This resistant genotype can be used in marker-assisted selection to develop resistant elite cultivars. 相似文献
38.
39.
Pankaj Lal Janaki R. R. Alavalapati Marian Marinescu Jagannadha Rao Matta Puneet Dwivedi Andres Susaeta 《Journal of Sustainable Forestry》2013,32(8):736-755
Bioenergy production has increased significantly in the last decade, and recent legislative efforts such as the discussion draft for the American Clean Energy and Security Act of 2009 and the Energy Independence and Security Act (EISA) of 2007 are expected to encourage even more growth. The growing demand for bioenergy will necessitate production of large quantities of woody biomass and plant residues if it is to be met. However, concerns are being raised as to how increased pressures will affect the sustainability of woody biomass. In order to avoid potential pitfalls and ensure the sustainability of wood-based bioenergy systems, a set of sustainability indicators needs to be developed. Some of these indicators can be based on standards similar to those developed for sustainable forest management, energy balances, greenhouse gas emission reductions, and existing codes and guidelines for biomass harvesting. This article discusses a potential set of sustainability indicators encompassing ecological, economic, and social principles for harvesting woody biomass for bioenergy. The extent to which existing standards and certification systems reflect these indicators is elaborated upon. Methods for making these standards operational are also suggested. 相似文献
40.
Chandra S. Prabhakar Pankaj Sood Sarbjit S. Kanwar Prem N. Sharma Ajay Kumar Pawan K. Mehta 《Phytoparasitica》2013,41(2):193-201
Gut bacteria of fruit fly, Bactrocera tau (Walker) (Diptera: Tephritidae), were isolated and the isolates attractive to B. tau adults were characterized using morphological, biochemical and 16S rRNA analyses to determine their taxonomic position. Based upon morphological, biochemical and 16S rRNA sequences (on the basis of closest match), five gut bacterial species of B. tau were characterized as Delftia acidovorans, Pseudomonas putida, Flavobacterium sp., Defluvibacter sp. and Ochrobactrum sp., of which four bacterial isolates, viz., Delftia acidovorans, Flavobacterium sp., Defluvibacter sp. and Ochrobactrum sp. are new records from guts of the fruit fly species. 相似文献