Showing papers by "Jawaharlal Nehru University published in 1985"
TL;DR: The Kolar Schist belt of the Dharwar Craton of South India is an Archean greenstone belt dominated by metavolcanal amphibolites as discussed by the authors.
Abstract: The Kolar Schist Belt of the Dharwar Craton of South India is an Archean greenstone belt dominated by
metavolcanic rocks. The mafic metavolcanic rocks occur as komatiitic and tholeiitic amphibolites. The komatiitic
amphibolites occur along the margins of the N-S trending, synformal belt. They are much less abundant than the
tholeiitic amphibolites and have 14 to 21-3 wt. per cent MgO. The komatiitic amphibolites from the west/central part
of the belt have two distinctive REE patterns: (1) those enriched in the middle to light REE but depleted in Ce
relative to Nd; and (2) those with patterns that are convex up, i.e. depleted in both light and heavy REE, although
more depleted in the light REE. Associated tholeiites have light REE depleted to flat REE patterns. Komatiitic and
tholeiitic amphibolites from the eastern part of the belt have enriched light REE patterns. The tholeiitic
amphibolites from the Kolar Schist Belt are similar to the TH I and TH II types of Archean tholeiites of Condie
(1981). The komatiitic amphibolites are similar to komatiites and komatiitic basalts of Barberton Mountainland, but
have higher FeO and TiO 2 abundances and lower Yb/Gd ratios. The petrogenetic interpretations for these
rocks are based primarily on a modification of the MgO-FeO diagram of Hanson & Langmuir (1978), and modelling of
Zr, Ni and REE. All of the rocks have undergone some fractionation. While the modelling does not give accurate
temperatures, pressures, compositions and extents of melting of the mantle sources for the various amphibolites, it
does present an approach which can be used for estimating these parameters. For example, the komatiitic amphibolites
appear to be derived from melts generated by 10 to 25 per cent melting of the mantle over a range of depths and
temperatures greater than 80 km and 1575°C. The variation in the P-T conditions of magma generation is possibly
due to adiabatic melting in mantle diapirs with a range of FeO/MgO ratios. If the tholeiitic amphibolites are
derived from similar mantle sources (it is not clear that they are), their parent melts may have been generated by
similar extents of melting, but at depths of less than 80 km. The komatiitic amphibolites from the west central part
of the belt were generated from light REE depleted mantle, whereas those from the eastern part of the belt appear to
have been generated from light REE enriched mantle. The sources for the komatiitic amphibolites in both areas were
significantly enriched in FeO relative to pyrolite. Thus, a light REE depleted and a light REE enriched source
appear to have provided mafic volcanics with similar major element chemistry to this belt during its
evolution.
144 citations
TL;DR: In this article, the average chemical compositions of river-borne sediments from the Indian sub-continent have been calculated on the basis of analysis of more than 120 samples, and the average concentration values for each of the major drainage basins, and average and inter-basin differences are discussed in relation to weathering processes in the drainage basin.
113 citations
TL;DR: In this article, the authors investigate the reasons for the muted formation and development of capitalist relations in Indian agriculture, even while commercialisation in output markets has advanced considerably, and argue that the desperate dependence on land as the basis for survival, with no alternative permanent means of livelihood, perpetuates the perverse exchange relations and retards productive accumulation.
Abstract: This is an attempt to investigate the reasons for the muted formation and development of capitalist relations in Indian agriculture, even while commercialisation in output markets has advanced considerably. Analysing the qualitatively differing character of exchange involvement, resting on the class basis of a differentiated peasantry, we have noted the differential dynamics that commercialisation entails for different classes and its overall, macroeconomic consequences. We argue that the desperate dependence on land as the basis for survival, with no alternative permanent means of livelihood, perpetuates the perverse exchange relations and retards productive accumulation. Most employment‐generating schemes sponsored by the state turn out to be ameliorative, providing only an intermittent supplementary source of income. This, along with the weak pull of a tardy industrial growth, only stabilises the petty‐holders. It is the preponderance or otherwise of petty‐holders, who are in no position to undertake p...
109 citations
TL;DR: It is proved that if σ is a fuzzy subset of S and μσ is the strongest fuzzy relation on S that is a fuzzier relation on σ, then μσ are a fuzzy subgroup if and only if �x is a furry subgroup.
70 citations
TL;DR: Red light stimulated calcium uptake in maize leaf protoplasts upto 140% over the dark control and 5-Hydroxytryptamine also enhanced calcium absorption in dark, upto the red level, suggesting a possible role of phosphoinositide for signal transduction in calcium uptake for phytochrome mediated responses in higher plants.
52 citations
TL;DR: There was a dose-related decrease in the number of fetuses possessing ossified coccygeal vertebrae while an increase in the Number of Fetuses with unossified 5th metacarpals, which indicated a delay in skeletal maturity, particularly in those fetuses exposed prenatally to the betel nut extract of the unprocessed variety.
49 citations
TL;DR: Betel leaf extract at the dose levels used in the present study did not affect the body weight gain among rats and no appreciable degree of inhibition of tumor growth was noticed.
36 citations
TL;DR: Dose-related increase in the production of abnormally shaped sperms and UDS response of the early spermatids following arecoline treatment expressed its genotoxic potential in the mouse germ cells.
Abstract: The ability of arecoline, an alkaloid of betel nut, to induce abnormality in the shape of sperm heads and unscheduled DNA synthesis (UDS) in the early spermatid stages of Swiss albino mice was studied. Treatment of mice with arecoline at the dose levels of 20, 40 and 80 mg/kg elicited dose-related increase in the number of abnormal sperm heads, as well as the unscheduled incorporation of [3H]thymidine into the DNA of early spermatids. Such increase in the production of abnormally shaped sperms and UDS response of the early spermatids following arecoline treatment expressed its genotoxic potential in the mouse germ cells.
33 citations
TL;DR: It is considered that radioprotection against oxic component possibly results from the competition of caffeine with oxygen for e-aq, whereas radiosensitization of the anoxic component is, at least partly, due to restoration of physico-chemical environment achieved by oxygen alone in the irradiated cells.
Abstract: Data on the differential modification of the oxic and anoxic components of radiation clastogenesis by caffeine already published in the literature have been briefly reviewed, additional unpublished data relevant for consideration of possible mechanisms have been presented and the possible events in terms of radiation chemistry have been discussed. It is considered that radioprotection against toxic component possibly results from the competition of caffeine with oxygen for eaq−, whereas radiosensitization of the anoxic component is, at least partly, due to restoration of physico-chemical environment achieved by oxygen alone in the irradiated cells. These reactions involve eaq, °OH and H2O2 formed in the cells exposed to ionizing radiation.
28 citations
TL;DR: It is postulated that the high peroxidase activity and high sulfite turnover rate possessed by Z. mays provided a relatively high resistance against SO 2 toxicity.
24 citations
TL;DR: It is apparent that yeast lipids regulate many membrane functions and also have decisive involvement in its structure, and a multidisciplinary approach is required where both its physical and physiological parameters should be simultaneously studied.
Abstract: Publisher Summary This chapter describes several aspects of lipids with regard to their involvement in the structure and function of yeast membrane. The neutral lipid composition of the majority of yeasts consists of mainly triacylglycerols, free sterols, sterol esters, and free fatty acids. The predominant component among neutral lipids is triacylglycerol, whereas the levels of sterol esters, free sterols, and free fatty acids vary between trace amounts to 7–8%. The lipid composition of yeast exhibits great variation depending upon its growth conditions. Yeast is an ideal model for ascertaining the involvement of lipids in its structure and function. However, yeast has not been fully exploited to predict a detailed relationship between its structure and function. It is apparent that yeast lipids regulate many membrane functions and also have decisive involvement in its structure. To have greater insight into the relationship of lipid and yeast membrane, a multidisciplinary approach is required where both its physical and physiological parameters should be simultaneously studied.
TL;DR: The exogenous supply of Fe2+ during irradiation was found to eliminate the 'threshold dose' which has to be delivered before MPG shows an 'enhancement effect'.
Abstract: SummaryRadiation-induced microsomal lipid peroxidation was measured following γ-irradiation (66–399 Gy) in the presence or absence of 2-mercaptopropionylglycine (MPG) at low and high concentrations (0·03 and 0·1 mg/ml). At high concentrations of MPG, enhancement of lipid peroxidation was observed instead of reduction. Following γ-irradiation at 266·4 Gy, lipid peroxidation increased with increasing concentrations of MPG. The spontaneous lipid peroxidation also increased with increasing concentrations of MPG. When MPG and EDTA were added together, radioprotection was observed even at high concentrations of MPG after different doses of radiation. An increase in radioprotection with increasing concentrations of MPG in the presence of EDTA at 266·4 Gy was also observed. The exogenous supply of Fe2+ during irradiation was found to eliminate the ‘threshold dose’ which has to be delivered before MPG shows an ‘enhancement effect’. A possible mechanism for the enhancement of radiation-induced lipid peroxidation is...
TL;DR: In this paper, the average composition of the Cauvery river at several locations from the catchment to the river mouth, the downstream profile of sediment load, annual erosion rates, solute and sediment fluxes and have predicted on long term changes.
Abstract: Samples of water and sediments were collected over a three year period from the entire region of Cauvery river basin excluding the estuary. On the basis of our observations, we have calculated the average composition of the Cauvery river at several locations from the catchment to the river mouth, the downstream profile of sediment load, annual erosion rates, solute and sediment fluxes and have predicted on long term changes. The sediment chemistry was determined by x-ray fluorescence (xrf) technique, and calculated mean compositions of the Cauvery and its tributary bed and the suspended sediment were compared to those of world average river sediments. Downstream profiles of some of the elements appear to be controlled by size and mineralogical characteristics besides local factors specific to the location of the samples. Interelemental relationships indicated good correlation among the transition elements indicating their co-genetic behaviour within the drainage basin.
TL;DR: In this article, arecoline, a major betel nut alkaloid, was tested for its effectiveness in inducing micronuclei in fetal mouse blood after transplacental exposure late in the gestation period.
Abstract: Arecoline, a major betel nut alkaloid, was tested for its effectiveness in inducing micronuclei in fetal mouse blood after transplacental exposure late in the gestation period. Positive results were obtained and a linear dose-response relationship was expressed when pregnant mice were treated with arecoline at dose levels of 20, 40 and 80 mg/kg and micronucleated polychromatic erythrocytes from fetal blood were subsequently analysed.
TL;DR: Rat kidney L-alanine:4,5-dioxovalerate transaminase, which may be involved in the formation of aminolevulinic acid in mammalian cells, was purified 82-fold to apparent homogeneity with a 19% yield and was the most efficient amino donor and stereospecific for the L-isomer.
TL;DR: The kinetic properties of the purified brain pyruvate kinase suggest that the enzyme may be distinct from the muscle or liver enzymes.
TL;DR: An independent action of blue light and light operating via phytochrome, in the control of nitrite reductase activity was revealed and the accumulation of nitrate was unaffected either by a red light pulse followed by a subsequent dark period, or by continuous blue light.
Abstract: Summary
Irradiation with red light for 5 min stimulated nitrite reductase activity in 5-d-old etiolated seedlings of Sorghum bicolor. The stimulation was less when measured after a subsequent dark period of 12 h than after one of 24 h. A short period of irradiation with blue light did not alter the enzyme activity nor did it elicit any effect even if given for 4–6 h prior to the red light irradiation. Exposure to blue light for 12 h prior to the red light treatment increased the enzyme activity, when measured after 12 h of darkness, to the same level as that obtained by red light irradiation alone followed by 24 h of darkness. Blue light given continuously for 24 h increased nitrite reductase activity and this increase was inhibited by 6-methylpurine (5 μg ml−1) or cycloheximide (25 μg ml−1). Transfer of seedlings to continuous white light for 6 h after treatment with a pulse of red light followed by 24 h of darkness, or with continuous blue light for 24 h, revealed an independent action of blue light and light operating via phytochrome, in the control of nitrite reductase activity. The accumulation of nitrate was unaffected either by a red light pulse followed by a subsequent dark period, or by continuous blue light. In contrast, continuous white light led to an increased accumulation of nitrate.
TL;DR: In this paper, Peasant production and medieval Indian society are discussed. But their focus is on the production process and not the social structure of the people involved in the process of production.
Abstract: (1985). Peasant production and medieval Indian society. The Journal of Peasant Studies: Vol. 12, Feudalism and Non‐European Societies, pp. 228-251.
TL;DR: Drugs likeL-ethionine, 1,10-phenanthroline and 3-(2-thienyl)-DL-alanine, which arrestSaccharomyces cerevisiae cells in the G1 phase, were unable to arrestCandida albicans cells, however, C.Albicans could be arrested in G1 after a prolonged stationary phase.
Abstract: Drugs likeL-ethionine, 1,10-phenanthroline and 3-(2-thienyl)-DL-alanine which arrestSaccharomyces cerevisiae cells in the G1 phase, were unable to arrestCandida albicans cells. However,C. albicans could be arrested in G1 after a prolonged stationary phase. As compared to normal cells, there was a selective reduction in the level of accumulation of valine and glutamate in G1-arrested cells, while the phospholipid polar head group ratio was not significantly altered. When G1-arrestedC. albicans cells were again allowed to grow, the level of different phospholipids started increasing at about the time of bud emergence (2.5 h) whereas reduced levels of accumulated valine and glutamate recovered within 1 h. The recovery of phospholipids and amino acid transport are two distinct events during the progression ofG. albicans cells from G1 to S phase.
TL;DR: A correlation was established between the retardation of growth and development of effluent-treated rice seedlings with the activities of some key enzymes regulating growth andDevelopment.
01 Jan 1985
TL;DR: The results indicate that malate-aspartate shuttle is probably stimulated under diabetic conditions to enable glycolysis to continue and ATP levels to be restored partially, particularly in cerebellum and liver.
Abstract: Regionally selective and time-dependent variations were observed in the activity of brain aspartate aminotransferase at early phases of diabetes. Malate dehydrogenase activity showed an opposite pattern of changes in soluble and particulate fractions of cerebral hemispheres and brain stem, with cerebellum showing consistent increase in the activity. The activity of both the enzymes increased significantly in liver, in contrast to heart where malate dehydrogenase activity decreased in particulate fraction. Insulin treatment to diabetic animals restored the enzymes to near control levels at early stages of diabetes, except in liver. The results indicate that malate-aspartate shuttle is probably stimulated under diabetic conditions to enable glycolysis to continue and ATP levels to be restored partially, particularly in cerebellum and liver.
TL;DR: For six sediment cores collected from Yamuna river (tributary of Ganges) around Delhi, rate of sedimentation was determined by the226Ra−210Pb method as discussed by the authors.
Abstract: For six sediment cores collected from Yamuna river (tributary of Ganges) around Delhi, rate of sedimentation was determined by the226Ra−210Pb method. While an average rate of 42 mm/y is obtained, there are variations core to core. A clear-cut downstream increase in the rate, from 5 mm/y when the river enters Delhi, to 80 mm/y when it leaves Delhi, indicates solid waste contribution from the urban areas. The sediment flux of 4000 mg/cm2/y is not balanced by the calculated rate of erosion (40 tonnes/km2/y) in the river. Thus, much of the sediment flux is of local origin.
TL;DR: Light-induced changes in the membrane lipid compositions were studied in pea leaves and in protoplasts and a plasmamembrane-enriched fraction and PI increased with a concomitant decrease in PC, and the galactolipid constituent of the PMEF showed no change.
TL;DR: There was no effect of light and benzimidazole in retarding the loss in photochemical activity, although the same preserved the chlorophyll contents as well as characteristics of the chloroplast absorption spectrum.
Abstract: The possibilities of an interaction between light and the growth regulator benzimidazole in retarding senescence-induced changes in activity of chloroplasts isolated from detached wheat (Triticum aestivum L. cv. Kalyansona) leaves have been investigated. The effect of benzimidazole on the rate of degradation of chlorophylls in light depended on the quality of light used. Far-red irradiation given to detached leaves in the presence of benzimidazole retarded the pigment loss more significantly than did white or red light of similar intensity. Senescence-induced loss in chloroplast photochemical activity was higher than the loss of chlorophylls. Loss of photosystem I activity was greater than photosystem II activity. Benzimidazole maintained the gramicidin-mediated enhancement in whole chain electron transport uniformly throughout the incubation period irrespective of the light quality. There was no effect of light and benzimidazole in retarding the loss in photochemical activity, although the same preserved the chlorophyll contents as well as characteristics of the chloroplast absorption spectrum.
TL;DR: Investigation of the effect of perturbing the interfacial water structure on the osmotic shrinkage properties, such as water permeability and extent of shrinkage of egg lecithin liposomes found it to arise from concentration-dependent structural transitions of the ordered water at the membrane-aqueous interface.
Abstract: The role of large amounts of membrane-bound water in regulating various functions of the membrane is not clear at present. We have investigated the effect of perturbing the interfacial water structure on the osmotic shrinkage properties, such as water permeability and extent of shrinkage of egg lecithin liposomes. Water structure was perturbed by a series of reagents which have been earlier reported to affect phase transition of dipalmitoyl phosphatidylcholine liposomes by perturbing interfacial water structure. Anomalous variations of osmotic shrinkage properties with concentration of structure maker and breaker reagents have been interpreted to arise from concentration-dependent structural transitions of the ordered water at the membrane-aqueous interface. Various modes of interaction of these reagents on interfacial structured water have been suggested. Influence of molecular size and functional groups on the molecule in actions of some structure makers and breakers were also observed.
TL;DR: The removal of 3′,5′‐cyclic AMP‐dependent protein kinase from the microsomes by sodium dodecyl sulphate treatment abolished the activation and/or inhibition of the Na+,K+‐ATPase by aldehyde; it can be inferred that 3‐methoxy‐4‐hydroxybenzaldehyde‐ analogue of MAO is involved in the regulation of Na+.
Abstract: :
Kinetic studies on the action of monoamine oxidase (MAO) in the regulation of Na+,K+-ATPase were performed using 3-methoxy-4-hydroxybenzaldehyde (MHB), which is an analogue of 3-methoxy-4-hydroxyphenylacetylaldehyde (product of MAO-catalysed reaction with dopamine as substrate). It was observed that at 2.6 μM MHB, the activation of Na+,K+-ATPase may be the result of the removal of the inhibitory Ca2+, thereby increasing the Vmax. Double-reciprocal plots of Pi versus MHB showed that Ca2+ counteracted the effect of the aldehyde not by changing the Km, but be decreasing the Vmax of the Na+,K+-ATPase stimulation. The removal of 3′,5′-cyclic AMP-dependent protein kinase from the microsomes by sodium dodecyl sulphate treatment abolished the activation and/or inhibition of the Na+,K+-ATPase by aldehyde; it can therefore be inferred that 3′,5′-cyclic AMP-dependent protein kinase is involved in the regulation of Na+,K+-ATPase.
TL;DR: L‐Alanine: 4,5‐dioxovalerate transaminase Heme biosynthesis Hemin End product inhibitor Hemin end product inhibitor
TL;DR: Dark grown (20-day-old) callus obtained from explants of Brassica oleracea var.
TL;DR: It appeared that control of the acid and alkaline phosphatases might be affected by 2 independent initial actions of phytochrome.
Abstract: A short pulse of red light or continuous far-red light enhanced the activities of acid and alkaline phosphatases in 5-day-old etiolated sorghum cv. Pusa Chari 6 seedlings compared with the dark controls. For 30 min after the red light pulse 100% and 80% of the red/far-red photoreversibilitys was maintained for the acid and alkaline phosphatases, resp. Thereafter, the photoreversibility escape reaction was fast, being completed within 180 min. Cycloheximide and 6-methyl purine markedly inhibited red light enhancement of the activities of the phosphatases, but chloramphenicol, lincomycin and rifamycin SV were ineffective. In spite of photoregulation of both the phosphatases at the time of de novo synthesis, it appeared that control of the acid and alkaline phosphatases might be affected by 2 independent initial actions of phytochrome