Ambient air monitoring for suspended particulate matter was carried over a period of one year in some coal mining areas of the Raniganj coalfield. Concentrations of seven elements in suspended particulate matter were determined. The set of data obtained was analysed to determine the sources of trace elements by factor analysis. The data could be interpreted on the basis of five factors. These factors are attributed to various sources of particulate matter by noting the dependence of factors on the elements. 相似文献
Molecular methods, including DNA probes, were used to identify and enumerate pathogenic Vibrio species in the Chesapeake Bay; our data indicated that Vibrio vulnificus exhibits seasonal fluctuations in number. Our work included a characterization of total microbial communities from the Bay; development of microarrays that identify and quantify the diversity of those communities; and observation of temporal changes in those communities. To identify members of the microbial community, we amplified the 16S rDNA gene from community DNA isolated from a biofilm sample collected from the Chesapeake Bay in February, 2000. The resultant 75 sequences were 95% or more similar to 7 species including two recently described Shewanella species, baltica and frigidimarina, that have not been previously isolated from the Chesapeake. When the genera of bacteria from biofilm after culturing are compared to those detected by subcloning amplified 16S fragments from community DNA, the cultured sample exhibited a strong bias. In oysters collected in February, the most common bacteria were previously unknown. Based on our 16S findings, we are developing microarrays to detect these and other microbial species in these estuarine communities. The microarrays will detect each species using four distinct loci, with the multiple loci serving as an internal control. The accuracy of the microarray will be measured using sentinel species such as Aeromonas species, Escherichia coli, and Vibrio vulnificus. Using microarrays, it should be possible to determine the annual fluctuations of bacterial species (culturable and non-culturable, pathogenic and non-pathogenic). The data may be applied to understanding patterns of environmental change; assessing the health of the Bay; and evaluating the risk of human illness associated with exposure to and ingestion of water and shellfish. 相似文献
Pesticide-induced toxicity is a serious issue which has resulted in plethora of diseases all over the world. The organophosphate pesticide malathion has caused many incidents of poisoning such as cardiac manifestations. The present study was designed to evaluate the effect of Syzygium cumini on malathion-induced cardiotoxicity. Dose optimization of malathion and polyphenols such as curcumin, (?)-epicatechin, gallic acid, butylated hydroxyl toluene, etc. was done by MTT cell proliferation assay. Nuclear deformities, ROS production, and integrity of extra cellular matrix components were analyzed by different techniques. S. cumini methanolic pulp extract (MPE), a naturally derived gallic acid-enriched antioxidant was taken to study its effect on malathion-induced toxicity. Nuclear deformities, ROS production, and integrity of extra cellular matrix components were also analyzed. Twenty micrograms per milliliter LD50 dose of malathion was found to cause stress-mediated responses in H9C2 cell line. Among all the polyphenols, gallic acid showed the most significant protection against stress. Gallic acid-enriched methanolic S. cumini pulp extract (MPE) showed 59.76 %?±?0.05, 81.61 %?±?1.37, 73.33 %?±?1.33, 77.19 %?±?2.38 and 64.19 %?±?1.43 maximum inhibition for DPPH, ABTS, NO, H2O2 and superoxide ion, respectively, as compared to ethanolic pulp extract and aqueous pulp extract. Our study suggests that S. cumini MPE has the ability to protect against the malathion-mediated oxidative stress in cardiac myocytes. 相似文献
Chlorantraniliprole, an anthranilic diamide insecticide with novel mode of action, is found effective against several lepidopteran as well as coleopteran, dipteran, and hemipteran pests. The present studies were carried out to study the persistence pattern of chlorantraniliprole on sugarcane field soil following application of granule formulation. The residues of chlorantraniliprole were estimated using high performance liquid chromatograph (HPLC) and confirmed by liquid chromatograph-mass spectrometry (LC-MS/MS). Following application of chlorantraniliprole (Ferterra 0.4G) at 100 and 200 g a.i. ha?1, the average initial deposits of chlorantraniliprole were observed to be 0.88 and 1.59 mg kg?1, respectively. These residues dissipated below the limit of quantification (LOQ) of 0.01 mg kg?1 after 56 days of the application of insecticides at both the dosages. The half-life values (t1/2) of chlorantraniliprole were worked out to be 8.36 and 8.25 days, at recommended and double the recommended dosages, respectively. 相似文献
The automobile exhausts are one of the major sources of particulate matter in urban areas and these particles are known to influence the atmospheric chemistry in a variety of ways. Because of this, the oxidation of dissolved sulfur dioxide by oxygen was studied in aqueous suspensions of particulates, obtained by scraping the particles deposited inside a diesel truck exhaust pipe (DEP). A variation in pH showed the rate to increase with increase in pH from 5.22 to about ~6.3 and to decrease thereafter becoming very slow at pH?=?8.2. In acetate-buffered medium, the reaction rate was higher than the rate in unbuffered medium at the same pH. Further, the rate was found to be higher in suspension than in the leachate under otherwise identical conditions. And, the reaction rate in the blank reaction was the slowest. This appears to be due to catalysis by leached metal ions in leachate and due to catalysis by leached metal ions and particulate surface both in suspensions. The kinetics of dissolved SO2 oxidation in acetate-buffered medium as well as in unbuffered medium at pH?=?5.22 were defined by rate law: kobs?=?k0?+?kcat[DEP], where kobs and k0 are observed rate constants in the presence and the absence of DEP and kcat is the rate constant for DEP-catalyzed pathway. At pH?=?8.2, the reaction rate was strongly inhibited by DEP in buffered and unbuffered media. Results suggest that the DEP would have an inhibiting effect in those areas where rainwater pH is 7 or more. These results at high pH are of particular significance to the Indian subcontinent, because of high rainwater pH. Conversely, it indicates the DEP to retard the oxidation of dissolved SO2 and control rainwater acidification.
Controlled release nanoformulations of carbendazim (Methyl 1H-benzimidazol-2-ylcarbamate), a systemic fungicide, have been prepared using laboratory synthesized poly(ethylene glycols) (PEGs)-based functionalized amphiphilic copolymers. The release kinetics of carbendazim from developed controlled release (CR) formulations was studied and compared with that of the commercially available 50% Wettable Powder (WP). Further, the bioefficacy evaluation of developed formulations was done against plant pathogenic fungi Rhizoctonia solani by the poison food technique method. The release of maximum amount of carbendazim from developed formulations was dependent on the molecular weight of PEGs and was found to increase with increasing molecular weights. The range of carbendazim release was found to be between 10th to 35th day as compared to commercial formulation which was up to 7th day. The diffusion exponent (n value) of carbendazim in water ranged from 0.37 to 0.52 in the tested formulations. The half-release (t1/2) values ranged between 9.47 and 24.20 days, and the period of optimum availability (POA) of carbendazim ranged from 9.15 to 26.63 days. Also, ED50 values of the developed formulations vary from 0.40 to 0.74 mg L?1. These formulations can be used to optimize the release of carbendazim to achieve disease control for the desired period depending on the matrix of the polymer used. 相似文献
Environmental Science and Pollution Research - Present work describes a laboratory study aiming at assessing the impact of sewage treatment plant (STP) effluents on fish health by means of... 相似文献