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Showing papers by "Banaras Hindu University published in 1989"


Journal ArticleDOI
06 Apr 1989-Nature
TL;DR: In this paper, the authors show that a reciprocal relationship exists between microbial biomass and plant growth rate and suggest that microbial immobilization may be a main source of nutrients for the plants and may lead to nutrient conservation.
Abstract: MORE than half of all tropical soils are highly weathered, leached and impoverished, requiring the ecosystem to develop nutrient-conserving mechanisms1,2. Nutrient retention and withdrawal mechanisms are most effective in nutrient-poor systems3,4. Thus, although dry tropical forests and savanna have the potential capacity to grow at high rates5,6, this capacity is strictly limited by climate and nutrients. Our studies on these nutrient-poor ecosystems show that a reciprocal relationship exists between microbial biomass and plant growth rate. This suggests that microbial immobilization may be a main source of nutrients for the plants and may lead to nutrient conservation.

590 citations


Journal ArticleDOI
TL;DR: Two new glycowithanolides isolated from Withania somnifera Dun.
Abstract: Two new glycowithanolides, sitoindoside IX (1) and sitoindoside X (2), isolated from Withania somnifera Dun., were evaluated for their immunomodulatory and CNS effects (anti-stress, memory and learning) in laboratory animals, because the plant extract is used by practitioners of the Indian systems of medicine for similar purposes. The two compounds, in doses of 100–400 μg/mouse, produced statistically significant mobilization and activation of peritoneal macrophages, phagocytosis and increased activity of the lysosomal enzymes secreted by the activated macrophages. Both these compounds (50–200 mg/kg p.o.) also produced significant anti-stress activity in albino mice and rats and augmented learning acquisition and memory retention in both young and old rats. These findings are consistent with the use of W. somnifera, in Ayurveda, to attenuate cerebral function deficits in the geriatric population and to provide non-specific host defence.

152 citations


Journal ArticleDOI
TL;DR: In this paper, the results indicated that the native forest soil lost about 57% and 62% organic C and total N, respectively, in the 0-10 cm layer after 15 years of cultivation.
Abstract: Fifteen- and forty-year-old cropfields developed from a dry tropical forest were examined for soil organic C and total N and soil microbial C and N. The 15-year-old field had never been manured while the 40-year-old field had been fertilized with farmyard manure every year. The native forest soil was also examined. The results indicated that the native forest soil lost about 57% and 62% organic C and total N, respectively, in the 0–10 cm layer after 15 years of cultivation. The microbial C and N contents of the forest soil were greater than those of the cultivated soils. Application of farmyard manure increased the biomass-C and -N levels in the cultivated soil but the values were still markedly lower than in the forest soil. There was an appreciable seasonal variation in biomass C and N, the values being highest in summer and lowest in the rainy season. During an annual cycle, biomass-C contents varied from 180 to 727 μg g−1 and N from 20 to 80 μg g−1 dry soil, and both were linearly related. Microbial biomass C represented 1.6%–3.6% of total soil organic C and microbial biomass N represented 1.7% 1–4.4% of soil organic N.

97 citations


01 Jan 1989
TL;DR: In this paper, the present status of the field of solid state ionics is updated, starting with an overview of recent trends in ionics and concluding with the assessment of future implications.
Abstract: Superionic solids and solid electrolytes are a special group of materials showing high ionic conductivity with tremendous technological potential This book updates the present status of the field Starting with an overview of recent trends in solid state ionics, the book ends with the assessment of future implications Different theoretical, experimental (including NMR), and materials aspects have been covered along with applications Important materials covered include alkali and silver ion conductors, fluorites, Nasicon, heterogeneous solid electrolytes, and glasses The theoretical topics covered in this volume include phenomenological models, fractal techniques, the pre-exponential problem, and fluctuations

86 citations


Journal ArticleDOI
TL;DR: Results suggest possible role of proteins and amino acids in confering salt tolerance in sugarcane cultivars and salt stressed seedlings compared to susceptibles.
Abstract: Seeds of four rice cultivars differing in salt tolerance when grown under increasing level of NaCl salinity and seedling vigour as well as metabolic status of total and soluble proteins, amino acids were evaluated in seedlings at increasing days of growth it was observed that increasing level of salinity caused loss in dry wt. of seedlings as well as reduction in lengths of root and shoot. In both sets of cultivars salt stressed seedlings showed higher levels of total as well as soluble proteins, total amino acids compared to non salinized seedlings. In roots of salt susceptible cvs. Ratna and Jaya increased salinity up to 14 mmhos/cm remarkably increased total as well as soluble protein level whereas in shoots moderate level of salinity increased protein level compared to controls and higher salinity level caused suppression in such increase. Tolerant cultivars always maintained higher levels of total as well as soluble proteins and total amino acids in salt stressed seedlings compared to susceptibles. Amino acids which accumulated greatly in salinized seedlings were arginine, phenylalanine, alanine, leucine, proline, valine and glutamine. Results suggest possible role of proteins and amino acids in confering salt tolerance in rice.

85 citations


Journal ArticleDOI
TL;DR: In this article, a classic example of inverted Himalayan metamorphism is described in the Darjeeling-Sikkim region, where the different parageneses of pelitic rocks containing chlorite, biotite, garnet, staurolite, kyanite, sillimanite, plagioclase and K-feldspar are documented by a variety of textures resulting from continuous and discontinuous reactions in the different zones.
Abstract: The Darjeeling-Sikkim region provides a classic example of inverted Himalayan metamorphism. The different parageneses of pelitic rocks containing chlorite, biotite, garnet, staurolite, kyanite, sillimanite, plagioclase and K-feldspar are documented by a variety of textures resulting from continuous and discontinuous reactions in the different zones. Microprobe data of coexisting minerals show that XMg varies in the order: garnet < staurolite < biotite < chlorite. White mica is a solid solution between muscovite and phengite. Garnet is mostly almandine-rich and shows normal growth zoning in the lower part of the Main Central Thrust (MCT) zone, and reverse zoning in the upper part of the zone. Chemographical relations and inferred reactions for different zones are portrayed in AFM space. In the low-grade zones oriented chlorites and micas and rolled garnets grew syntectonically, and were succeeded by cross-cutting chlorites and micas and garnet rims. In the upper zones sillimanite, kyanite and staurolite crystallized during a static inter-kinematic phase. P-T contitions of metamorphism, estimated through different models of geothermobarometry, are estimated to have been 580°c for the garnet zone to a maximum of 770°c for the sillimanite zone. The preferred values of pressure range from 5.0 kbar to 7.7 kbar. Models to explain the inverted metamorphism include overthrusting of a hot high Himalayan slab along a c. 5 km wide ductile MCT zone and the syn- or post-metamorphic folding of isograds.

79 citations


Journal ArticleDOI
TL;DR: A chronological description of the discoveries of the effects of histamine on ovarian function is given and suggestions for future research in this area are made.
Abstract: Mast cells, endothelial cells, basophils and platelets are potential sources of histamine in the ovary. Little is known about the role of the latter three cell types in ovarian function. Several studies have revealed changes in the number and degranulation (release of histamine) of mast cells in the ovary during the cycle. Mast cells degranulate on pro-oestrus in the rodent ovary, and mast cells numbers increase in the theca externa of the dominant follicle in the bovine ovary. In rodents, mast cells are limited to the ovarian hilum and are not observed in follicles, corpora lutea and interstitium; this contrasts with larger species such as man, cows and monkeys where mast cells are observed throughout the ovary. Evidence is accumulating that mast cell degranulation in the ovary may be regulated by neuronal input. Neurones have been shown to have close morphological relationships with mast cells in the ovary. Histamine participates in regulating capillary permeability and blood flow in the ovary. These actions are induced by injections of LH, yet the mechanism by which LH induces mast cell degranulation is unknown. Histamine stimulates ovarian contractility, ovulation and follicular progesterone secretion in vitro. Whether these actions of histamine occur in vivo are currently unknown. This review gives a chronological description of the discoveries of the effects of histamine on ovarian function and makes suggestions for future research in this area.

69 citations


Journal ArticleDOI
TL;DR: Haemanthus kalbreyeri provides a new source of the anti-tumour alkaloid, pancratistatine, and the plant growth regulatory profile of these two alkaloids and three other isocarbostyril congeners, narciclasine, 7-deoxynareiclasines, and pancratiside, is appraised.

62 citations


Journal ArticleDOI
01 Sep 1989-Wear
TL;DR: In this article, the wear rate of a 6061 aluminium alloy-14 vol.% graphite composite with graphite particle protrusions was evaluated against a rotating EN25 steel disc using a pin-on-disc apparatus.

58 citations


Journal ArticleDOI
TL;DR: The results strongly indicate that histamine has a role in the formation of early traumatic brain edema and that this reaction can be influenced by pharmacological procedures.

57 citations


Journal ArticleDOI
TL;DR: The results suggest that the combination of pimozide and luteinizing hormone-releasing hormone analogue and LHRHa can be used as a simple and efficient method for inducing ovulation in the catfish.

Journal ArticleDOI
TL;DR: In this paper, the vibrational overtones of CH stretching oscillators are reported as observed by conventional IR spectroscopy and dual-beam thermal lensing spectrograms for benzene, fluorobenzene, chlorobenzenes, bromobenzeni, and benzonitrile in the liquid phase at room temperature.

Journal ArticleDOI
TL;DR: Factors such as pH, organic carbon sources (glucose and acetate), and amino acids were found to regulate the toxicity of all three herbicides to N. linckia, which was found to be more tolerant to 2,4-D (lethal doses 1500-2000 micrograms/ml) than to Machete and Saturn.

Journal ArticleDOI
TL;DR: In this paper, the impact of air pollutants on vegetation around Obra thermal power plant (1550 M W capacity) in the Mirzapur district of Uttar Pradesh was investigated. And the results showed that the SO2 and SPM concentrations were quite high in the immediate vicinity of the power plant and there also exists a direct relationship between the concentration of SPM in air and amount of dust deposited on leaf surfaces.

Book ChapterDOI
TL;DR: In this article, the available experimental and theoretical information concerning the bed-to-surface heat-transfer coefficient is discussed, along with the design of the gas distributor plate and the relative size of heat transfer surface and the fluidized bed.
Abstract: Publisher Summary This chapter discusses the available experimental and theoretical information concerning the bed to surface heat-transfer coefficient. The high heat transfer rates achieved for boiler tubes immersed in fluidized-bed coal combustors, along with their in situ capability to remove SO x and suppress the emission of NO x in high-pressure systems, have led to their exploitation as a promising technology for the generation of electrical power from sulfur-rich coal. The atmospheric fluidized-bed combustion (AFBC) technology has been claimed to be ready for commercialization for some time. On the other hand, thermodynamic analysis has shown that pressurized fluidized-bed combustion (PFBC) of coal in the combined-cycle mode is very efficient and economically preferable. Heat transfer rate from an immersed surface in a gas-fluidized bed depends upon a number of factors, such as the size, size range, shape, and properties of the bed particles; operating conditions, temperature, pressure, fluidizing velocity, and properties of the gas; shape, size, surface finish, and orientation of the heat transfer surface; the relative size of the heat transfer surface and the fluidized bed; and on the design of the gas distributor plate.

Journal ArticleDOI
TL;DR: Eight weeks of latent iron deficiency in weaned rats maintained on an experimental low iron content diet did not significantly alter the packed cell volume and hemoglobin concentration; however, the hepatic and brain nonheme iron contents decreased by 66% and 21% (p < 0.001), respectively.
Abstract: Eight weeks of latent iron deficiency in weaned rats maintained on an experimental low iron content diet (18-20 mg/kg) did not significantly alter the packed cell volume and hemoglobin concentration; however, the hepatic and brain nonheme iron contents decreased by 66% and 21% (p less than 0.001), respectively. The tryptophan concentration decreased by 31% and 34% in liver and brain, respectively, in rats on experimental diet (p less than 0.01). The brain 5-hydroxytryptamine and 5-hydroxyindoleacetic acid contents were reduced by 21% and 23% (p less than 0.01 and p less than 0.02), respectively. However, in the brain, weight, protein, DNA, and the activities of monoamine oxidase, aldehyde dehydrogenase, and liver tryptophan oxygenase were found to remain unaltered. When rehabilitated with a diet containing 390 mg/kg iron, rats previously maintained on the experimental diet for 2 weeks showed partial recovery in tryptophan levels both in liver and brain. However, brain 5-hydroxytryptamine and 5-hydroxyindoleacetic acid levels remained unaltered. The hepatic iron content improved without any change in brain iron content. The latent iron deficiency produced significant alterations in the metabolism of 5-hydroxytryptamine and brain iron content that could not be recovered 2 weeks after the iron rehabilitation.

Journal ArticleDOI
TL;DR: In this article, the effects of rewarding and punishing verbal reinforcers on verbal operant conditioning as a function of extraversion-introversion were investigated, and the results showed that extraverts compared to introverts and ambiverts condition better with the rewarding reinforcer compared to the punishing one.
Abstract: The present investigation was designed to study the effects of rewarding and punishing verbal reinforcers on verbal operant conditioning as a function of extraversion-introversion. A randomized block design involving three levels of extraversion (extraverts, ambiverts and introverts) and two verbal reinforcement conditions (‘good’ and ‘poor’), was replicated 20 times. One hundred and twenty undergraduate and postgraduate female students were individually subjected to Taffel's verbal conditioning procedure. The study supports the following conclusions: (1) extraverts as compared to introverts and ambiverts condition better with the rewarding reinforcer (‘good’) while the introverts compared to extraverts and ambiverts condition better with the punishing reinforcer (‘poor’); (2) extraverts condition better with the rewarding reinforcer compared to the punishing one, whereas the introverts condition better with the punishing reinforcer compared to the rewarding one; (3) ambiverts condition comparably with both the rewarding and punishing reinforcers.

Journal ArticleDOI
TL;DR: Evidence is presented to suggest that the bunchy top, die-back, abnormal inflorescence and blossom blight disease of Mangifera indica are interlinked and can be expressed as a disease cycle in mango malformation.
Abstract: Evidence is presented to suggest that the bunchy top, die-back, abnormal inflorescence and blossom blight disease of Mangifera indica are interlinked and can be expressed as a disease cycle in mango malformation. The morphological and biochemical connections among these symptoms, induced by Fusarium moniliforme var. subglutinans Wollenw. and Reink., are appraised. Partial control of the mango malformation has been accomplished by spraying the diseased parts with mangiferin-Zn2+ and mangiferin-Cu2+ chelates. The salutory effect of niangiferin-metal chelates is evidenced by the revival of normal balance of mangiferin and the micronutrients in the diseased parts, dechne in the fungal population and emergence of healthy shoots.

Journal ArticleDOI
TL;DR: In this article, the chain ratio type estimators for ratio of two population means using two auxiliary characters have been derived and the expressions for bias and mean square error of these estimators were derived.
Abstract: In this paper we have proposed chain ratio type estimators for ratio of two population means using two auxiliary characters. The expressions for bias and mean square error of these estimators have been derived. A comparison of the proposed estimator with that of double sampling estimator has been made in terms of mean square error. An emperical study has also been made.

Journal ArticleDOI
TL;DR: The immobilized cells showed a stronger positive correlation between Cu adsorption and uptake and the total Cu uptake was almost two and a half-times more than their free cell counterpart under identical experimental conditions.
Abstract: Copper uptake in free and immobilized cells of the cyanobacterium Nostoc calcicola has been examined. The immobilized cells invariably maintained a higher profile of Cu intake rate (12.7 nmol mg−1 protein min−1) over the free cells (6.0 nmol mg−1 protein min−1). The total Cu uptake in immobilized cells was almost two and a half-times more than their free cell counterpart under identical experimental conditions. Also, the immobilized cells showed a stronger positive correlation between Cu adsorption and uptake. The results have been discussed in terms of improved metabolic efficiency of immobilized cells.

Journal ArticleDOI
01 Jun 1989-JOM
TL;DR: In this paper, an emerging class of metallic materials (nanocrystalline metals) can lead to enhanced mechanical and physical properties such as strength, modulus, ductility, wear characteristics and corrosion behavior.
Abstract: Increasing systems requirements, particularly in the aerospace industry, demand improved material performance. One emerging class of metallic materials—nanocrystalline metals—can lead to enhanced mechanical and physical properties such as strength, modulus, ductility, wear characteristics and corrosion behavior.

Journal ArticleDOI
TL;DR: This age‐related increase in DNA methylation occurs both at CCGG sites of the RDS and in the entire genome, which may alter chromatin conformation and gene expression in the brain as the rat ages.

Journal ArticleDOI
TL;DR: In this paper, the epireflective hull of the standard two-point Sierpinski space is known to coincide with the subcategory of T0 topological spaces, and the corresponding T0-objects are identified.

Journal ArticleDOI
TL;DR: A fixed point theorem for a generalized nonexpansive fuzzy mapping is given which extends a result of Bose and Sahani [3], and a theorem of Kirk and Downing on fixed points of a multi-valued mapping for a fuzzy mapping on a metric space is extended.

Journal ArticleDOI
TL;DR: Group groups did not differ in the ability to identify emotions from partial facial expressions, however, schizophrenics were significantly poorer than anxiety neurotics and controls in identifying emotions from full facial expressions.
Abstract: Schizophrenics, anxiety neurotics, and nonpatient control subjects were asked to identify the emotion expressed in partial (upper-middle-lower) and full facial expression of four negative emotions: sadness, fear, anger and disgust. Groups did not differ in the ability to identify emotions from partial facial expressions, however, schizophrenics were significantly poorer than anxiety neurotics and controls in identifying emotions from full facial expressions.

Journal ArticleDOI
TL;DR: Shilajit and different combinations of FAs, MCB and DDP provided statistically significant protection to antigen‐induced degranulation of sensitized mast cells, markedly inhibited the antigen‐ induced spasm of sensurized guinea‐pig ileum, and prevented mast cell disruption induced by compound 48/80.
Abstract: The effects of shilajit and the combined effects of its main constituents, fulvic acids (FAs), 4′-methoxy-6-carbomethoxybiphenyl (MCB) and 3,8-dihydroxy-dibenzo-α-pyrone (DDP), were studied in relation to the degranulation and disruption of mast cells against noxious stimuli. Shilajit and different combinations of FAs, MCB and DDP provided statistically significant protection to antigen-induced degranulation of sensitized mast cells, markedly inhibited the antigen-induced spasm of sensitized guinea-pig ileum, and prevented mast cell disruption induced by compound 48/80. The findings are appraised in view of the clinical use of shilajit in the treatment of allergic disorders in Ayurvedic medicine.

Journal ArticleDOI
TL;DR: The results of in vivo studies in mice showed prolonged tissue levels of pentazocine from the multiple O/W/O emulsions in comparison to aqueous drug solution and simple O/w emulsion.
Abstract: Multiple O/W/O emulsions containing pentazocine were prepared and tested in vitro and in vivo. The effect of two different concentrations of three additives, viz. sodium chloride, glucose and glycerol, location of the drug either in one or any two phases of the O/W/O emulsions and pH of the receptor fluid on in vitro release characteristics of the drug was studied. All the parameters influenced the drug release. Multiple O/W/O emulsions gave higher extent of drug release than the simple O/W emulsions. The results of in vivo studies in mice showed prolonged tissue levels of pentazocine from the multiple O/W/O emulsions in comparison to aqueous drug solution and simple O/W emulsion.

Journal Article
TL;DR: Abroagation of anti-inflammatory effect of Picrorhiza kurroa extract by beta-adrenergic blockade was confirmed, which suggests alteration in cell-surface biology by PK treatment, and selective PK influence on membrane linked activation events in inflammatory effector cells could be the basis ofAnti-inflammatory and perhaps other biological activities reported with the herb.
Abstract: In this work abroagation of anti-inflammatory effect of Picrorhiza kurroa extract (PK) by beta-adrenergic blockade was confirmed, which suggests alteration in cell-surface biology by PK treatment. Blockade of protein synthesis by cycloheximide pretreatment reduced PK effect, suggesting protein mediation. Metabolic inhibitor dinitrophenol inhibited inflammatory cedema equally in control and PK treated animals, and masking of PK effect was concluded. Discriminations of anti-inflammatory mechanism(s) of PK and the latter two cytotoxic agents was inferred from these observations and from existing knowledge. Selective PK influence on membrane linked activation events in inflammatory effector cells could be the basis of anti-inflammatory and perhaps other biological activities reported with the herb.

Journal ArticleDOI
TL;DR: In this article, an empirical model has been tested to understand the kinetics of Pb(II) removal at different concentrations and temperatures for the present system and activation energy has been determined and found to be 8.533 Kjoules.
Abstract: The removal of Pb(II) is dependent of contact time, concentration, pH and temperature, of the solution. The various rate parameters of adsorption, have been determined at different concentrations and temperatures for the present system. An empirical model has been tested to understand the kinetics of Pb(II) removal at different concentrations. The pore diffusion is mainly rate controlling step. The Langmuir isotherm has been applied to find out the adsorption parameters involved in the present adsorption process. The isosteric heat of adsorption has been determined at different surface coverages of the adsorbent. The negative value of enthalpy change (? H= ‐7.269 Kcal mol‐1) suggests the exothermic nature of the adsorption process. The activation energy has been determined and found to be ‐8.533 Kjoules. The various thermodynamic parameters have been calculated to understand the clear mechanism involved in the adsorption process.

Journal ArticleDOI
TL;DR: Results suggest possible relationship between levels of free amino acids arginine, leucine, alanine, valine, glutamine and proline and degree of salt tolerance in rice and all amino acids should be considered in combination as indices for saltolerance in rice.
Abstract: Metabolic status of total and individual free amino acids were studied in endosperms and embryoaxes of four rice cultivars differing in salt tolerance, growing under increasing levels of saline stress. At all saline treatment levels and in controls salt tolerant cultivars had higher levels of total free amino acids in germinating seed parts than sensitives. Individual free amino acids which always maintained higher levels in germinating tolerant seeds over sensitives were aspartic acid, arginine, glycine and leucine. Salinity caused accumulation of free amino acids in germinating seed parts in all cultivars. Maximum accumulation was of arginine followed by leucine, alanine, valine, glutamine and proline. Individual amino acids accumulated greatly in tolerant cultivars than sensitives. Increased salinity caused decrease in the levels of aspartic acid, serine, glutamic acid, glycine, lysine and histidine in growing embryoaxes. Results suggest possible relationship between levels of free amino acids arginine, leucine, alanine, valine, glutamine and proline and degree of salt tolerance in rice. These all amino acids should be considered in combination as indices for salt tolerance in rice.