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51.
Grigor’ev A. A. Devi N. M. Kukarskikh V. V. V’yukhin S. O. Galimova A. A. Moiseev P. A. Fomin V. V. 《Russian Journal of Ecology》2019,50(4):311-322
Russian Journal of Ecology - Analysis of the age structure of Dahurian larch (Larix gmelinii Rupr.) forests in the western part of the Putorana Plateau (Sukhie Gory Range) and comparison of... 相似文献
52.
Devi Prasad Mishra Patitapaban Sahu Durga Charan Panigrahi Vivekanand Jha R. Lokeswara Patnaik 《Environmental science and pollution research international》2014,21(3):2305-2312
This paper presents a comparative study of 222Rn emanation from the ore and backfill tailings in an underground uranium mine located at Jaduguda, India. The effects of surface area, porosity, 226Ra and moisture contents on 222Rn emanation rate were examined. The study revealed that the bulk porosity of backfill tailings is more than two orders of magnitude than that of the ore. The geometric mean radon emanation rates from the ore body and backfill tailings were found to be 10.01?×?10?3 and 1.03 Bq m?2 s?1, respectively. Significant positive linear correlations between 222Rn emanation rate and the 226Ra content of ore and tailings were observed. For normalised 226Ra content, the 222Rn emanation rate from tailings was found to be 283 times higher than the ore due to higher bulk porosity and surface area. The relative radon emanation from the tailings with moisture fraction of 0.14 was found to be 2.4 times higher than the oven-dried tailings. The study suggested that the mill tailings used as a backfill material significantly contributes to radon emanation as compared to the ore body itself and the 226Ra content and bulk porosity are the dominant factors for radon emanation into the mine atmosphere. 相似文献
53.
M. Yokesh Babu L. Palanikumar N. Nagarani V. Janaki Devi S. Ramesh Kumar C. M. Ramakritinan A. K. Kumaraguru 《Environmental science and pollution research international》2014,21(16):9604-9616
Marine macroalgae have evolved a different mechanism to maintain physiological concentrations of essential metal ions and non-essential metals. The objective of the present work was to evaluate the antioxidant response and DNA damage of copper and cadmium ions in three halophytes, namely, Acanthophora spicifera, Chaetomorpha antennina, and Ulva reticulata. Accumulation of copper was significantly higher (P?0.05) than that of cadmium. Biochemical responses showed that copper was considerably more toxic than cadmium (P?0.05). Decreases in glutathione content and fluctuations of super oxide dismutase, catalase, and glutathione peroxidase activities were observed corresponding to time and concentration of exposure. Interestingly, it was also observed that antioxidant levels decreased as a result of metal accumulation, which may be due to free radicals generated by copper and cadmium in seaweeds. The present study also showed that copper and cadmium increased oxidative stress and induced antioxidant defense systems against reactive oxygen species. The order of toxicity for metals in the studied seaweeds was U. reticulata > A. spicifera > C. antennina. DNA damage index analysis supported that copper was significantly (P?0.05) more toxic than cadmium. Bioaccumulation, biochemical responses, and DNA damage observed in the here analyzed marine macroalgae after exposure to selected metals indicate that these marine organisms represent useful bioindicators of marine pollution. 相似文献
54.
Naser A. Anjum Pallavi Sharma Sarvajeet S. Gill Mirza Hasanuzzaman Ekhlaque A. Khan Kiran Kachhap Amal A. Mohamed Palaniswamy Thangavel Gurumayum Devmanjuri Devi Palanisamy Vasudhevan Adriano Sofo Nafees A. Khan Amarendra Narayan Misra Alexander S. Lukatkin Harminder Pal Singh Eduarda Pereira Narendra Tuteja 《Environmental science and pollution research international》2016,23(19):19002-19029
Plants have to counteract unavoidable stress-caused anomalies such as oxidative stress to sustain their lives and serve heterotrophic organisms including humans. Among major enzymatic antioxidants, catalase (CAT; EC 1.11.1.6) and ascorbate peroxidase (APX; EC 1.11.1.11) are representative heme enzymes meant for metabolizing stress-provoked reactive oxygen species (ROS; such as H2O2) and controlling their potential impacts on cellular metabolism and functions. CAT mainly occurs in peroxisomes and catalyzes the dismutation reaction without requiring any reductant; whereas, APX has a higher affinity for H2O2 and utilizes ascorbate (AsA) as specific electron donor for the reduction of H2O2 into H2O in organelles including chloroplasts, cytosol, mitochondria, and peroxisomes. Literature is extensive on the glutathione-associated H2O2-metabolizing systems in plants. However, discussion is meager or scattered in the literature available on the biochemical and genomic characterization as well as techniques for the assays of CAT and APX and their modulation in plants under abiotic stresses. This paper aims (a) to introduce oxidative stress-causative factors and highlights their relationship with abiotic stresses in plants; (b) to overview structure, occurrence, and significance of CAT and APX in plants; (c) to summarize the principles of current technologies used to assay CAT and APX in plants; (d) to appraise available literature on the modulation of CAT and APX in plants under major abiotic stresses; and finally, (e) to consider a brief cross-talk on the CAT and APX, and this also highlights the aspects unexplored so far. 相似文献
55.
Pramanik S Devi S Chowdhary S Surendran ST Krishnamurthi K Chakrabarti T 《Chemosphere》2011,82(7):941-946
Reduction in DNA repair capacity is associated with increased rates of birth defects, cancer, and accelerated ageing. Genetic polymorphisms in DNA repair genes might influence the repair activities of the enzymes predisposing individuals to cancer risk. Owing to the presence of these genetic variants, inter-individual and ethnic differences in DNA repair capacity have been observed in various populations. India harbors enormous genetic, cultural and linguistic diversity. The present study was undertaken to determine the allele and genotype frequencies of four non-synonymous SNPs, XRCC1 Arg399Gln (C > T, rs25487), XRCC3 Thr241Met (G > A, rs861539), XPD Lys751Gln (T > G, rs13181), and OGG1 Ser326Cys (C > G, rs1052133) in the Maharashtrian population, residing in the Vidarbha region of central India and to compare them with HapMap and other Indian populations. The variant alleles of these polymorphisms have been found to be positively associated with different forms of cancer in several genetic epidemiological studies. The basic prevalence of these polymorphisms in the general population must be known to evaluate their significance in risk assessment in cancer and other phenotypes. About 215 healthy and unrelated individuals from the Maharashtrian population were genotyped for each of these four polymorphisms using PCR-RFLP. The allele and genotype frequency distribution at the four DNA repair gene loci among Maharashtrians revealed a characteristic pattern. To the best of our knowledge, this is the first report of these DNA repair gene polymorphisms in a central Indian population. 相似文献
56.
The aim of this study was to examine effects of lead (Pb)-based paints on malondialdehyde (MDA) levels as an indicator for lipid peroxidation; and on activities of serum antioxidant enzymes activities such as superoxide dismutase (SOD) and glutathione peroxidase (GPx) in industrial painters. A total of 67 male painters and 50 age-matched and gender-matched controls were included in this cross-sectional study. There were 19 smokers and 48 non-smokers in the paint-exposed group and 20 smokers and 30 non-smokers in the control group. Hemoglobin concentrations were lower in painters’ blood compared to controls. The blood Pb concentrations were higher in painters compared to controls. SOD and GPx activities were significantly lower in painters compared to controls. MDA concentration was found to be significantly elevated. Smoking was found to be a major confounder. Data suggest that Pb-based paints affect oxidant parameters in occupationally exposed workers. 相似文献
57.
S. Palani S. Raja R. Praveen Kumar K. Sakthivel K. Devi B. Senthil Kumar 《毒物与环境化学》2013,95(6):1199-1211
Hyperlipidemia is an associated complication of diabetes mellitus. Many spices and herbs are known to be hypoglycemic. Mahonia leschenaultia Takeda (Berberidaceae) (MLT) is a traditional medicinal plant that is commonly used against diseases in India and other Asian countries. The aim of this study is to identify the phytoconstituents by gas chromatography–mass spectrography (GC–MS) and evaluate the antihyperglycemic and antihyperlipidemic effects of the ethanol extract of MLT on streptozotocin (STZ)-induced diabetic rats. Phytoconstituents like oleicacid, 9,12-octadecadienoic acid (Z, Z)-n-hexadecanoic acid were identified as high % peak when compared with other compounds by GC–MS. STZ-induced diabetic animals were fed with plant extracts at different doses (250 or 500 mg kg?1 body wt) of ethanol extract of MLT. The results of the study revealed a significant increase in total hemoglobin and glycosylated hemoglobin along with the reduction in hyperglycemia and hyperlipidemia effects in MLT-treated STZ-induced diabetic rats compared to diabetic only rats. Further, ethanol extracts of MLT-treated animals at 500 mg kg?1 showed that shrinkage of β cells of islets of Langerhans was restored as evidenced by histological studies of pancreas of diabetic animals. Thus the ethanol extract of MLT might serve as a reliable adjuvant for antihyperglycemic and antihyperlipidemic effects of STZ, and may be promising for development of phytomedicines for diabetes mellitus. 相似文献
58.
Roshan Appa V. A. Mhaisalkar Amit Bafana S. Saravana Devi Kannan Krishnamurthi Tapan Chakrabarti Pravin K. Naoghare 《Environmental monitoring and assessment》2018,190(8):489
Environmental occurrence of CECs poses a great threat to both aquatic life and human health. The aim of this study was to optimize and validate SPE/LC-(ESI)MS-MS method for simultaneous quantitative monitoring of two sub-classes of CECs (pharmaceuticals and hormones) and to estimate the concentrations of select CECs in environmental water samples. For all the tested analytes, recoveries in laboratory reagent water were greater than 81%. Average percent (relative standard deviation) RSD of the analytes in recovery, repeatability, and reproducibility experiments were ≤?10%. Determination coefficients (r2) of primidone, diclofenac, testosterone, and progesterone were estimated to be 0.9979, 0.9972, 0.9968, and 0.9962, respectively. Limits of detection (LOD) for primidone, diclofenac, testosterone, and progesterone were 4.63 ng/L, 5.36 ng/L, 0.55 ng/L, and 0.88 ng/L, respectively. Limits of quantification (LOQ) for primidone, diclofenac, testosterone, and progesterone were 14.72 ng/L, 17.06 ng/L, 1.766 ng/L, and 2.813 ng/L, respectively. Average recoveries in environmental water and wastewater samples were greater than 74% and RSD were ≤?7%. Trace levels (68.33–125.70 ng/L) of primidone were detected in four environmental water samples, whereas diclofenac was not detected in any of the tested sample. Trace levels of progesterone were observed in two environmental samples (16.64 –203.73 ng/L), whereas testosterone was detected in STP inlet sample (178.16 ng/L). 相似文献
59.
K. K. Sharma Irani Mukherjee Balwinder Singh Sanjay K. Sahoo N. S. Parihar B. N. Sharma V. D. Kale R. V. Nakat A. R. Walunj Saudamini Mohapatra A. K. Ahuja Debi Sharma Geeta Singh Rajbir Noniwal Sunita Devi 《Environmental monitoring and assessment》2014,186(11):7673-7682
Supervised field trials were conducted at four different agro-climatic zones in India to evaluate the dissipation pattern and risk assessment of flubendiamide on tomato. Flubendiamide 480 SC was sprayed on tomato at 48 and 96 g active ingredient (a.i.) ha?1. Samples of tomato fruits were drawn at 0, 1, 3, 5, 7, 10, 15, and 20 days after treatment. Quantification of residues was done on a high-performance liquid chromatography (HPLC) device with a photo diode array detector. The limit of quantification (LOQ) of this method was found to be 0.01 mg kg?1 while limit of detection (LOD) being 0.003 mg kg?1. Residues of flubendiamide were found below the determination limit of 0.01 mg kg?1 in 20 days at both the dosages in all the locations. The half-life of flubendiamide at an application rate of 48 g a.i.?ha?1 varied from 0.33 to 3.28 days and at 48-g a.i. ranged from 1.21 to 3.00 days. On the basis of data generated under the All India Network Project on Pesticide Residues, a preharvest interval (PHI) of 1 day has been recommended, and the flubendiamide 480 SC has been registered for its use on tomato by the Central Insecticide Board and Registration Committee, Ministry of Agriculture, Government of India. The maximum residue limit (MRL) of flubendiamide on tomato has been fixed by the Ministry of Health and Family Welfare, Government of India under Food Safety Standard Authority of India, as 0.07 μg g?1 after its risk assessment. 相似文献
60.
Gomathi Devi LN Krishnamurthy G 《Journal of environmental science and health. Part. B》2008,43(7):553-561
Photocatalytic degradation of the herbicide, pendimethalin (PM) was investigated with BaTiO3/TiO2 UV light system in the presence of peroxide and persulphate species in aqueous medium. The nanoparticles of BaTiO3 and TiO2 were obtained by gel to crystallite conversion method. These photo catalysts are characterized by energy dispersive x-ray analysis (EDX), scanning electron microscope (SEM), x-ray diffraction (XRD), and Brunauer-Emmett-Teller (BET) adsorption isotherm and reflectance spectral studies. The quantum yields for TiO2 and BaTiO3 for the degradation reactions are 3.166 Einstein m(-2) s(-1) and 2.729 Einstein m(-2) s(-1) and catalytic efficiencies are 6.0444 x 10(-7) mg(-2)h(-1)L2 and 5.403 x 10(-7) mg(-2)h(-1)L2, respectively as calculated from experimental results. BaTiO3 exhibited comparable photocatalytic efficiency in the degradation of pendimethalin as the most widely used TiO2 photocatalyst. The persulphate played an important role in enhancing the rate of degradation of pendimethalin when compared to hydrogen peroxide. The degradation process of pendimethalin followed the first-order kinetics and it is in agreement with Langmuir-Hinshelwood model of surface mechanism. The reason for high stability of pendimethalin for UV-degradation even in the presence of catalyst and oxidizing agents were explored. The higher rate of degradation was observed in alkaline medium at pH 11. The degradation process was monitored by spectroscopic techniques such as ultra violet-visible (UV-Vis), infrared (IR) and gas chromatography mass spectroscopy (GC-MS). The major intermediate products identified were: N-propyl-2-nitro-6-amino-3, 4-xylidine, (2, 3-dimethyl-5-nitro-6-hydroxy amine) phenol and N-Propyl-3, 4-dimethyl-2, 6-dinitroaniline by GC-MS analysis and the probable reaction mechanism has been proposed based on these products. 相似文献