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Abstract  

The time integral pertturbed angular correlation (TIPAC) technique is employed to study PAC parameters in aqueous solutions of biomolecules Bovine Serum Albumin (BSA), lysozyme and ethylenediaminetetraacetic acid disodium salt (EDTA), using radioactive147Nd as a probe. The attenuation coefficient (G22) is found to decrease with increasing concentration of BSA The effect of attenuation is more pronounced for protein molecules BSA and lysozyme than in the case of EDTA. The relaxation constant ( 2) increases with increasing concentration of the solution as well as with the increasing size of the solute molecule.

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Biochemical basis of disease resistance was studied by analysis of total phenols, peroxidase and ß-1,3-glucanase activities in calli of Fusarium wilt resistant and susceptible genotypes and one in vitro selected resistant cell line of chickpea (Cicer arietinum L.). The callus growth of cvs. JG62, C235 and WR315 was completely inhibited at 2% (v/v) concentration of culture filtrate of the fungus, whereas, the callus growth of in vitro selected resistant cell line FWR was not inhibited even at 4% (v/v) concentration of culture filtrate, indicating that a cultivar resistant under field conditions could show susceptibility under in vitro conditions. Total phenols were more in the resistant cell line than in the susceptible cultivars. However, increase in phenolics was higher in resistant cell line than in susceptible cultivars after treatment with the cultural filtrate, indicating that phenols reach an inhibitory level to the fungus in the resistant cell line. Peroxidase followed a similar pattern. Increase in ß-1,3-glucanase activity, after treatment, was higher in resistant cell line than in susceptible cultivars. Role of total phenols, peroxidase and ß-1,3-glucanase in defense against Fusarium wilt disease of chickpea is discussed.

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The analysis of the genotype × environmental interaction, which indicates the stability of genotypes, has always been part of plant breeding programmes before the release of varieties for commercial cultivation. In the present investigation the stability of seed yield, opium yield and morphine content in 11 advanced breeding lines of opium poppy was evaluated over five years. Combined ANOVA showed that both the main effects and interactions were significant, indicating the presence of genotype × environment interactions. The average seed yield and opium yield ranged from 10.41–16.92 q/ha and 45.21–59.85 kg/ha, respectively. Stability analysis involving the parameters bi, S 2 di, λi, s 2 , δ 2 , Wi, r 2 and CV identified four genotypes (BR330, BR333, BR229 and BR243) as ideal and stable for the traits studied. The level of association among different parameters obtained using Spearman’s rank correlation showed that Eberhart and Russell’s deviation from regression (S 2 di) was significantly and positively associated with s 2 , λi, δ 2 i and CV and negatively with r 2 . The parameters λi, s 2 , δ 2 i and CV also showed positive mutual association.

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Abstract  

Perturbed angular correlation parameters in biological material bovine serum albumin were determined using - sum peak method and time integral perturbed angular correlation technique, using160Tb as a probe. The attenuation coefficient G22 decreases with an increase in the concentration of the environment resulting in an increase in Äc, the correlation time.

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The study of seismic activity at some stage in 1963 to 2006 in the Western Nepal Himalaya and its adjoining regions (28–31°N and 79–82.3°E), reveal that seismicity is non-uniform in space and time. The analyses of fault-plane solutions of twenty-four earthquakes inferred that the Western part of Nepal Himalayan frontal arc is in compressed state in which seismic activity is dominated by thrust faulting. Based on orientation of P-axes, compressive stress directed north-south to northeast-southwest approximately perpendicular to the prevailing stress along the major trend of the Himalaya. Thrust faulting coupled with shallow dip of nodal planes reflects that the Indian continental lithosphere is under-thrusting at a shallow angle. This information suggests crustal shortening in north-south direction in which earthquakes are generated due to northward compression. In the adjoining Tibet parts earthquake activity is due to normal faulting with east-west extension. These might be due to the presence of a relatively strong Main Himalayan Thrust, the plate boundary fault below the Himalayas, would have favored the occurrence of thrusting. While, a weak Main Himalayan Thrust below Tibet along with initiation of the Main Central Thrust can explain South Tibetan Detachment (geodynamic process) and associated stress field in Western Nepal Himalaya and its adjoining regions.

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A series of unusual geological incidents have occurred throughout the Kerala State (southwest Peninsular India) during the year 2001 mainly in two active phases i.e. February to March, and June to November 2001. In the beginning during February-March 2001, oscillations and rise in water levels, wavy formations and spouting up of water in the open wells, cracks in the buildings, perceptible ground fissures, shaking of trees/bushes and enhanced microearthquake activity have occurred. Collapse of shallow open wells, draining of water, lowering of water level, land subsidence, ground fissures etc., and further increased microearthquake activity were the dominant incidents in various parts of the State during June to November 2001. Interestingly, no such incidents had occurred in the past in this region. The frequency of all the above incidents, including microearthquakes activity, reduced drastically to background level beyond November 2001 except a few earthquakes during 2002 and 2003. The incidents are distributed in a vast area irrespective of geology and topography right from coastal stretch to hinterlands in the Western Ghats of India. This chain of incidents was preceded by two moderate size earthquakes of M ~ 5 on 12 December 2000 and 7 January 2001 which were not capable to trigger such widespread incidents in the region. The temporal patterns of these incidents clearly indicate the phenomenon of rapid ground vibrations at several occasions possibly due to movement of crustal block along certain active fault. This geological process perhaps lead to uplift and tilt of the ground giving rise to several underground water related anomalies and incidents of land deformations. The temporal patterns of individual incident also did not show any clear inter-relationships indicating that all these incidents were caused by a single internal geological process possibly due to converging trend of tectonic stress through the process of redistribution. It is inferred that these incidents constitute a well defined patterns of precursory sequence to a future large seismic activity in the southwest part of Peninsular India. The existence of the present chain of events can be explained by dilatancy diffusion model. Using the spatial distribution of these incidents including microearthquake activity and past significant earthquakes, an east-west trending potential area (10.7-10.9°N; 76.0-76.8°E) is delineated in the central Kerala region as the preparatory zone for the location of future earthquake.

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Abstract  

Instrumental neutron activation analysis was performed on scalp hair and fingernail samples collected randomly from a group of heavily exposed healthy male industrial workers living in the cities of Hamilton and Toronto (Ont.), Canada. The concentrations of trace elements (Ag, Au, Br, Cd, Co, Cr, Cs, Fe, Hg, Lu, Mn, Mo, Rb, Ru and T3) were evaluated and compared for scalp hair and fingernails. Various trace elements show similar variations in the two kinds of samples. The results have also been compared with those for normal subjects from USA (scalp hair) and Canada (fingernails).

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
Sardool Ghumman
,
Rajender Singh
,
N. Sidhu
, and
H. Sahota

Abstract  

The perturbed angular correlation /P.A.C./ technique is employed to investigate the structures of barium ferrite and barium hexaferrite using radioactive133Ba /10.7 Y/ as a probe. The quadrupole interaction frequencies /WQ'S/ are found to be 9.68 and 12.02 Mrad sec–1 for barium ferrite and barium hexaferrite, respectively, showing a drift from usual cubic structure.

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Copper(II), silver(I) and lead(II) salts of N-(2,4-dinitrophenyl)-N-nitroglycine were prepared and characterised. The thermal behaviour of the salts in air and nitrogen atmospheres was studied by means of DTA and TG techniques. The environment appeared to have no effect on the mode of decomposition. While metal oxides are formed as the end-products of decomposition of the copper and lead salts, metallic silver plus carbon was found to be final product from the silver salt. The thermal stabilities of these salts follow the sequence silver salt>lead salt>copper salt.

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Abstract  

The literature on the normal content of uranium in urine is reviewed. The reported normal concentration has declined several orders of magnitude over the years, probably due to improvements in analytical technique rather than a real change. The lowest mean values were reported with spectrometry (mean of 23 ng/l in 12 subjects) and thermal ion mass spectrometry (3.4 ng/l in 1 subject). Even spectrometry is not sufficiently sensitive at normal levels, so that techniques such as fission track analysis or mass spectrometry must be used to obtain results above the detection limit of the technique for individual samples.

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