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Air pollution is a major contributor to several respiratory problems, it affects the whole population in general but children are more susceptible. Exposure to automobile exhaust is associated with increased respiratory symptoms and may impair lung function in children. In view of this, the study was conducted among the children of Delhi, the capital city of India, where ambient air quality was much above the National Ambient Air Quality Standards. The study was conducted in children aged 9–17 years. Pulmonary function test was carried out following the guideline of American Thoracic Society using a portable, electronic spirometer. Air quality data was collected from Central and State Pollution Control Boards. In addition, the level of particulate matter in indoor air was measured by portable laser photometer. Lung function was reduced in 43.5% schoolchildren of the urban area compared with 25.7% of control group. The urban children had increased prevalence of restrictive, obstructive, as well as combined type of lung functions deficits. Besides higher prevalence, the magnitude of lung function deficits was also much more in them. After controlling potential confounders like season, socioeconomic conditions and ETS, PM10 level in ambient air was found to be associated with restrictive (OR?=?1.35, 95% CI 1.07–1.58), obstructive (OR?=?1.45, 95% CI 1.16–1.82), and combined type of lung function deficits (OR?=?1.74, 95% CI 1.37–2.71) in children. Spearman's rank correlation test reaffirmed the association. The study confirms that the level of air pollution is affecting the children.  相似文献   
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Artemisia pallens Bess. is a low volume and high value essential oil plant used in perfumery, cosmetic and flavouring industries. On account of the failure of conventional procedures to induce variability in species, mutation techniques have been tried in our experiments. Dry and viable seeds (moisture content 8%) of homozygous pure breeding lines were subjected to 150–500 Gy doses of gamma rays and 0.01–0.1% ethyl methane sulphonate (EMS) for 8 h. Desirable qualitative mutants were recovered from segregating M2 generation (4,283 plants scored) raised as single plant progenies. The spectrum of morphological mutants included late and early flowering types; bushy and high yielding types; tall and more capitula-producing types and high oil and high davanone yielding types. These were raised through M3 families to evaluate stability and transmission of mutant characters. As such out of 15 different types selected in M2, only 11 types bred true to their characteristic variability. Based on their performance, the mutants were characterised depending upon their distinguishing features. Davanone, the main component of oil showed the maximum increase (64.22% against 54.64% in control) in mutant ‘S–5’ recovered from exposure with 250 Gy γ-rays. Mutant ‘E-6’ was economically most viable having increased oil biosynthesis (0.36% against 0.22% in control) and hence yields higher oil per unit area than the parental control (isolated from 0.05% EMS treatment).  相似文献   
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An assessment of arsenic contamination in Raipur city (21°14′N, 18°38′E) of Chhattisgarh in the central part of India is reported here, for a monitoring period between November 1996 to June 1997, in airborne dust particulates. The concentration level of As were higher in the industrial site, followed by heavy traffic as compared to other sites. The monthly atmospheric arsenic deposition, in μg As per g of dust fall, of 6 sites are in the range of 0.100(μ0.020)–4.00(μ0.020); site no. 1 industrial area, 0.100(μ0.020)–0.320(μ0.020); site no. 2 residential area, 0.044(μ0.070)–0.337(μ0.030); site no. 3 commercial area, 0.093(μ0.068)–1.870(μ0.020); site no. 4 residential area, 0.111(μ0.020)–1.912(μ0.010); site no. 5 residential area and 0.068(μ0.040)–3.037(μ0.060); site no. 6 heavy traffic area. The total annual flux of As in the fall-out at different zones is in the range 0.033–1.12 kg km-2 yr-1. The month wise collection and analysis of dust fall out rate between 3.0(μ0.10)–91.3(μ1.4) mt (metric tonnes) km-2 month-1 were observed at all 6 sampling sites. Anthropogenic and environmental factors play important roles in the contribution of arsenic in airborne particulate matters.  相似文献   
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A protein isolate was prepared from karanj seed (KPI) with 921.2 g protein/kg seed, which contained a negligible amount of anti‐nutritional factors and a balanced amino acid composition, especially rich in methionine. For 60‐day feeding trial, five isonitrogenous (300 g/kg CP) and isocaloric (15 MJ DE/kg) diets were formulated by replacing soybean protein isolate (SPI) on protein equivalent basis, KPI‐0 (control, 0 g/kg KPI); KPI‐25 (replacing 250 g/kg SPI protein with KPI); KPI‐50 (replacing 500 g/kg SPI protein with KPI); KPI‐75 (replacing 750 g/kg SPI protein with KPI) and KPI‐100 (replacing 1,000 g/kg SPI protein with KPI) for the feeding of L. rohita. The weight gain percentage, specific growth rate, feed conversion ratio and protein efficiency ratio were not significantly (p > .05) varied among the KPI fed and control groups. A significantly higher hepatosomatic index was recorded in the control and KPI‐25 groups compared with other groups. The whole‐body compositions, except ether extract, did not differ significantly (p > .05) among the groups. Digestive (amylase, protease, lipase and alkaline phosphatase) and metabolic enzyme activities (hexokinase, transaminases and lactate dehydrogenase) and glycogen stores were not significantly affected, whereas intestinal alkaline phosphatase differed significantly (p < .05). The RNA–DNA ratio was significantly (p < .05) higher in the KPI‐75 group. Thus, the study revealed that KPI can completely replace SPI protein at 191 g/kg inclusion level in the diets of L. rohita fingerlings.  相似文献   
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Gynoecious is an important economic trait of cucumber for determinant of earliness and yield, yet genetic mechanism is not well understood for this trait. The experiment was conducted using F2 mapping population by crossing of PPC-2, a gynoecious and parthenocarpic line with Pusa Uday (monoecious and non-parthenocarpic cultivar). Out of 179 SSR markers screened, 39 markers differentiated the gynoecious and monoecious parents. However, only 17 markers were segregating with F2 mapping population, those were used for genotyping and linkage map analysis and these markers were placed along with F locus on chromosome 6 covering a total distance of 100.4cM. The SSR markers, SSR13251 and UW020605 were found to be closely linked to gynoecious (F) locus at 1.0 and 4.5 cM, respectively. The segregation of F2 population of PPC-2 × Pusa Uday and GPC-1 × Punjab Naveen and test crosses for sex type herein suggested that single dominant gene controlled the gynoecious sex expression in cucumber particularly in gynoecious genotypes PPC-2 and GPC-1. Therefore, the monogenic dominant nature of gynoecious sex identified in the present experiment and SSR markers closely linked to the F locus will be useful in marker-assisted backcross breeding for transfering gynoecious trait into horticulturally desirable varieties.  相似文献   
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The diffuse reflectance Fourier transform spectroscopic (DRS-FTIR) method, using potassium bromide matrix, has been developed for the one-drop microdetermination of sulfite in beverage samples. The present method is very simple, rapid, and precise for the determination of sulfite. The nanogram level of sulfite determination is based on the selection of a quantitative analytical peak at 495 cm (-1) among the three observed vibrational peaks obtained by diffuse reflectance Fourier transform infrared spectroscopy (DRS-FTIR). As little as a single drop of sample is sufficient for quantitative analysis of sulfite. The limit of detection (LOD) and the limit of quantification (LOQ) of the method are found to be 8 and 40 ng of SO 3 (2-) 0.1 g (-1) of KBr matrix, respectively. The linear range of the method (LR) as well as the LOD based on the concentration of sulfite in the solution are 5-500 and 0.8 microg/mL, respectively. The precision in terms of standard deviation and relative standard deviation value at a level of 100 ng of SO 3 (2-) 0.1 g (-1) of KBr for n = 10 are found to be 2 ng of SO 3 (2-) and 2.3%, respectively. The relative standard deviation ( n = 10) for the determination of sulfite in beverage samples available in the local market was observed to be in the range of 2.4-7.8%. The method is free from interionic effects of foreign species. No sample pretreatment is required in this method. The proposed method avoids the requirement of large numbers and bulk amounts of reagents. The method is well-suited to the need of green chemistry.  相似文献   
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