Showing papers by "University of Madras published in 1987"
TL;DR: Pseudomonas fluorescens strains antagonistic to Sarocladium oryzae, the sheath rot pathogen of rice, were evaluated in greenhouse and field tests for suppression of Sh-R severity and enhancement of grain yields of rice.
Abstract: Pseudomonas fluorescens strains antagonistic to Sarocladium oryzae, the sheath rot (Sh-R) pathogen of rice (Oryza sativa L.), were evaluated in greenhouse and field tests for suppression of Sh-R severity and enhancement of grain yields of rice. Imprints of rice seedlings and a direct-observation technique of staining roots with fluorochromes confirmed the association of P. fluorescens with roots and the ability of the strain to move along shoot tips. In greenhouse tests, P. fluorescens-treated rice plants (cv. IR 20) showed a 54% reduction in the length of Sh-R lesions. In three field tests, treatment with P. fluorescens reduced the severity of Sh-R by 20 to 42% in five rice cultivars. Bacterization of rice cultivars with P. fluorescens enhanced plant height, number of tillers, and grain yields from 3 to 160%.
131 citations
TL;DR: Native strains of Pseudomonas fluorescens were examined for their ability to suppress the root and stem rot pathogen of peanut, Scterotium rolfsii, in greenhouse experiments and in in vitro plate tests.
Abstract: Native strains of Pseudomonas fluorescens were examined for their ability to suppress the root and stem rot pathogen of peanut, Scterotium rolfsii . P. fluorescens restricted the mycelial growth of S. rolfsii in in vitro plate tests. Sclerotia showed 10–20% and 50–60% germination losses after they were immersed in a bacterial cell suspension for 1 h and 1 week respectively. In greenhouse experiments, 99% of peanut plants were protected from S. rolfsii infection if they were inoculated with P. fluorescens (10 8 cfu ml −1 ). Non-bacterized S. rolfsii -infected plants wilted or died in 10 days and fresh weights of tops of these plants were significantly lower than those of plants inoculated with bacteria infected with S. rolfsii .
81 citations
TL;DR: The results indicate that the ion pairs may contribute to the stability of solvent‐exposed alpha helices, and since the stabilization of protein secondary structure, may throw light on the mechanism of protein folding.
Abstract: A survey of 47 globular proteins was made to determine the probability of occurrence of ion pairs separated by 1,2,3,... and 8 residues in the alpha helices. As a control, the probability of occurrence of like charged pairs was also determined. The survey showed that ion pairs of the type i,i +/- 3 and i, i +/- 4 are the most predominant. Such a preference was not observed for like charged pairs. The observed frequency of ion pairs is significantly greater than their expected frequency. The normalized frequencies of occurrence of the ion pairs were also found to increase generally with the helix length. These results indicate that the ion pairs may contribute to the stability of solvent-exposed alpha helices. Since the stabilization of protein secondary structure enhances the stability of protein tertiary structure, these results may throw light on the mechanism of protein folding.
60 citations
TL;DR: Bacillus subtilis utilized ferulic acid and its intermediates vanillin, vanillic acid, and protocatechuic acid as sole carbon source and Concentration of the inducer profoundly influenced the induction of the enzymes involved in ferulic Acid dissimilation.
Abstract: Bacillus subtilis utilized ferulic acid and its intermediates vanillin, vanillic acid, and protocatechuic acid as sole carbon source. The enzymes of the ferulic acid degradative pathway such as deacetylase, vanillin oxidase, vanillate-o-demethylase, and protocatechuate 3,4-dioxygenase were inducible in nature. Concentration of the inducer profoundly influenced the induction of the enzymes involved in ferulic acid dissimilation.
55 citations
TL;DR: The function of lipid peroxidation and the antiperoxidative enzymes of rat liver and kidney were studied in stone formation induced by intraperitoneal administration of sodium oxalate to observe a significantly pronounced release of malondialdehyde.
Abstract: The function of lipid peroxidation and the antiperoxidative enzymes of rat liver and kidney were studied in stone formation induced by intraperitoneal administration of sodium oxalate (7 mg/100 g body weight). The animals sacrificed 3 and 12 h after administration of sodium oxalate had higher level of malondialdehyde in liver and kidney than control animals. A significantly pronounced release of malondialdehyde was observed in treated liver and kidney homogenates when incubated with either ferrous sulphate or hydrogen peroxide compared to control liver and kidney. Superoxide dismutase activity was increased only in liver and not in kidney in treated animals compared to the control. A highly significant decrease in catalase activity was observed in both liver and kidney of treated animals.
38 citations
TL;DR: The qualitative and quantitative variations found in the AMPS content of spermatophoric components of two prawns have been discussed in relation to their adhesion to thelycum as well as sperm storage and maintenance pending fertilization.
33 citations
TL;DR: An overview of hydrogen energy research and development work in India can be found in this article, starting with a summary of the energy situation in the country and concluding with an overview of the various aspects of the hydrogen energy system.
26 citations
TL;DR: In this paper, the SUSY-based modified semiclassical quantization rule of Comtet et al. is demonstrated to be exact for solvable potentials by showing that all higher-order corrections vanish.
23 citations
TL;DR: The structure of the local anaesthetic benzocaine was solved by direct methods and refined to anR of 0·12 for 531 observed reflections as mentioned in this paper, where the packing of the molecule is stabilised by N−H … O hydrogen-bonds.
Abstract: The structure of the local anaesthetic benzocaine was solved by direct methods and refined to anR of 0·12 for 531 observed reflections The packing of the molecule is stabilised by N−H … O hydrogen-bonds (2–97 Â) The alkyl chain attached to the benzene ring is intrans-trans conformation The benzoic moiety shows a quinonoid character as found in some other local anaesthetics
22 citations
TL;DR: The results suggest that PRL plays a specific stimulatory influence on monkey prostate, and the combinations of these androgens with PRL/Br with TP/DHT enhanced the body weight, organ weights, and secretory activities.
Abstract: The effects of prolactin (PRL), bromocriptine (Br), testosterone propionate (TP), dihydro-testosterone (DHT), and the combinations of these androgens with PRL/Br on the growth and secretory activities of cranial and caudal prostates were studied in castrated mature monkeys, Macaco radiata. Castration decreased the body weight, organ weights, nucleic acids (DNA and RNA), phosphatases, and citric acid of cranial and caudal prostates. PRL did not alter the body weight but increased the organ weights, nucleic acids, phosphatase activities, and citric acid. Br given alone decreased the body weight and the secretory activities of prostates but caused no significant alteration in the nucleic acids. TP/DHT replacement brought back the body weight and prostatic nucleic acids to normal. It enhanced the weights, phosphatase activities, and citric acid contents of cranial and caudal prostates. PRL + TP/DHT enhanced the body weight, organ weights, and secretory activities. Br + TP/DHT decreased the body weight and secretory products of prostate but it did not produce any alteration in the organ weight and RNA content. These results suggest that PRL plays a specific stimulatory influence on monkey prostate.
21 citations
TL;DR: In this article, the authors investigated the kinetics of aqueous polymerization of acrylonitrile initiated by peroxomonosulphate Co(II) redox system in the range 30-50°C under nitrogen at a fixed ionic strength of 0.30 mol · dm −3.
TL;DR: Severity of stem-rot disease of peanut caused by Rhizoctonia solani was reduced by 54.9 and 68% in plants of two cultivars treated in the greenhouse with antagonistic strains ofPseudomonas fluorescens.
Abstract: Severity of stem-rot disease of peanut caused byRhizoctonia solani was reduced by 54.9 and 68% in plants of two cultivars treated in the greenhouse with antagonistic strains ofPseudomonas fluorescens. These strains were selected based on theirin vitro toxicity to mycelial growth and sclerotial germination ofR. solani. In field experiments, bacterization of peanuts withP. fluorescens resulted in taller plants (by 25.7%) and increased yields (by 59.0%).
TL;DR: Claisen rearrangement of methyl-3-aryloxy-2-(aryloxymethyl)prop-2-enoates (4) in refluxing N,N-diethylaniline gave 3-(2-hydroxyphenylmethylene) -3,4-dihydro-2H-1-benzopyran-2.1.
TL;DR: A new method for the analysis of linear singular systems via the single-term Walsh series (STWS) approach, which is very simple and direct and can easily be implemented on a digital computer.
Abstract: The paper presents a new method for the analysis of linear singular systems via the single-term Walsh series (STWS) approach. Block pulse and discrete solutions are obtained for any length of time. The method is very simple and direct and can easily be implemented on a digital computer.
TL;DR: A survey of blue-green algae occurring in rice fields in Kerala State (India), has been carried out, and ten taxa are recorded for the first time in a rice-field environment.
Abstract: A survey of blue-green algae occurring in rice fields in Kerala State (India), has been carried out. Among the thirty taxa identified and described, ten are recorded for the first time in a rice-field environment. The taxa included unicellular, non-heterocystous filamentous, heterocystous filamentous and heterotrichous forms.
TL;DR: The nature and levels of copper in different tissues after exposing the crabs to copper-rich medium are studied to indicate the relative importance of various tissues in accumulation an the possible mechanisms of regulation of the environmental copper.
Abstract: In the decapod crustaceans copper is distributed in various tissues. In these animals the tissue copper generally exists in four forms; ionic, bound to proteins, lipids and membrane. In the estuarine crab Scylla serrata, the haemolymph copper exists only in association with proteins, whereas in the hepatopancreas it exists in all the four forms and in gills it exists in all the forms except in combination with lipids. Although food is the major source of copper in decapod crustaceans evidence indicate that copper may be directly obtained from the environment. It was postulated earlier that in Scylla serrata the haemolymph and hepatopancreas may be involved in copper regulation. In the present work the authors have studied the nature and levels of copper in different tissues after exposing the crabs to copper-rich medium. The results indicate the relative importance of various tissues in accumulation an the possible mechanisms of regulation of the environmental copper. Besides, as a pre-requisite for studies of this kind, the toxic levels for different forms of copper were estimated since the form of toxicant is known to influence the toxicity to the decapod crustaceans.
TL;DR: Bacillus subtilis utilized guaiacol glyceryl ether (GGE) as sole carbon source and catabolized it via guaiacsol and catechol via the ortho pathway.
Abstract: Bacillus subtilis utilized guaiacol glyceryl ether (GGE) as sole carbon source and catabolized it via guaiacol and catechol. Cell free extracts of GGE grown cells contained high levels of catechol 1,2-dioxygenase and cleaved catechol via the ortho pathway. Nutrients such as sugars, organic acids, methanol, nitrogen and phosphate influenced the catabolism of GGE by B. subtilis.
TL;DR: A dissimilatory plasmid, designated as pAMB1, was effectively cured by mitomycin C treatment and was transferred to a Pseudomonas sp., with a transfer frequency of 2.2 × 10−5 transconjugants/donor cell as mentioned in this paper.
Abstract: Pseudomonas solanacearum degrades catechin to phloroglucinolcarboxylic acid, protocatechuic acid, catechol, phloroglucinol, resorcinol and hydroxyquinol, which is plasmid-encoded. This dissimilatory plasmid, designated as pAMB1, was effectively cured by mitomycin C treatment and was transferred to a Pseudomonas sp., with a transfer frequency of 2.2 × 10−5 transconjugants/donor cell. The cured strains did not utilize catechin or its intermediates, and lacked the plasmid.
TL;DR: In this paper, sufficient conditions for global relative controllability of non-linear systems with time-varying multiple delays in control and implicit derivatives are derived using the measure of noncompactness of a set and Darbo's fixed-point principle.
Abstract: Sufficient conditions for global relative controllability of non-linear systems with time-varying multiple delays in control and implicit derivatives are derived. The results are obtained using the measure of non-compactness of a set and Darbo's fixed-point principle.
TL;DR: In this paper, the hyperfine field distribution P(H) of METGLAS 2605CO (Fe67 Co18B14Si1) is evaluated at RT from the Mossbauer spectrum.
Abstract: The hyperfine field distribution P(H) of METGLAS 2605CO (Fe67 Co18B14Si1) is evaluated at RT from the Mossbauer spectrum. It is representative of a single amorphous phase. At a higher temperature, P(H) distribution develops distinct broad humps. A study of the temperature dependence of P(H) distribution reveals the phenomenon of amorphous phase separation.
TL;DR: In this paper, the existence of optimal control for nonlinear systems having implicit derivative with quadratic performance criteria was proved. But the authors did not consider the nonlinear system with implicit derivatives.
Abstract: We prove the existence of optimal control for nonlinear systems having implicit derivative with quadratic performance criteria.
TL;DR: Aspergillus flavus utilized gallic acid as sole carbon source and increased in presence of glucose and sucrose and the estradiol (meta) fission of gallic Acid by A. flavus was postulated.
TL;DR: In this paper, the authors used scaling law analysis to determine the critical exponent of the alpha-Fe, Fe2B and FeWB phases in amorphous Fe95-xW5Bx alloys with x = 15, 20 and 25.
Abstract: Thermomagnetic studies and X-ray analysis made on the amorphous Fe95-xW5Bx alloys with x=15, 20 and 25 show the presence of stable alpha -Fe, Fe2B and FeWB phases. Low-temperature (4.2-300 K) magnetisation measurements indicate the existence of spin waves and Stoner or single-particle excitations. Isochronal and isothermal annealing treatments reveal two stages of relaxation, one of which is attributed to compositional or chemical short-range ordering (CSRO). The value of the critical exponent beta for all the three compositions is determined to be 0.43 by means of scaling law analysis and it is found to be independent of annealing treatments.
TL;DR: It was concluded that central monoaminergic neurons were specifically influenced either directly or indirectly after meethanol administration and that the effect of methanol differed according to the brain area and its action on different monoaminerential systems were quite different.
TL;DR: The behavior of very high rotational states of the highly excited compound nuclear systems formed in fusion reactions is studied in the framework of the statistical theory and a shift in the yrast minima is predicted towards higher angular momentum states with the increase in the excitation energy and the entropy of the compound nuclear system.
Abstract: The behavior of very high rotational states of the highly excited compound nuclear systems formed in fusion reactions is studied in the framework of the statistical theory. The very high spin states populated in these reactions results in the observation of phenomena like backbending and yrast traps. The experimental data on the angular momentum limitation on fusion probability are reproduced at higher entropy values. Shape transitions are observed for the systems /sup 12/C+/sup 12/C, /sup 16/O+/sup 16/O, /sup 18/O+/sup 18/O, and /sup 40/Ca+/sup 40/Ca. We predict a shift in the yrast minima towards higher angular momentum states in the case of /sup 40/Ca+/sup 40/Ca with the increase in the excitation energy and the entropy of the compound nuclear system. Lines of constant entropy or constant level density are found to be almost equally spaced.
TL;DR: In this paper, the effect of thermal history on the glass transition temperature Tg of polystyrene, polyvinylchloride and polyethyleneterephthalate was studied using differential scanning calorimetry (DSC).
TL;DR: In this article, the thermal decomposition of different aniline-formaldehyde (A-F) resins (1:1, 1:2, 1.4 and 1:5) was studied in nitrogen and oxygen atmospheres and the validity of the linear kinetic compensation law was observed.
TL;DR: It is concluded that heparin interferes with wound healing by depriving the fibroblasts of their scaffold and causing cross linking of collagen and accelerated its degradation.
Abstract: Heparin with its ability to dissolve the fibrin clot exerts its major effect in the early stages of wound healing by depriving the fibroblasts of their scaffold. Heparin inhibits cross linking of collagen and accelerates its degradation. There is faulty orientation of the collagen fibrils in the heparinized wound. It may be concluded that heparin interferes with wound healing.
TL;DR: Injection of 16 mg of plumbagin per kg body weight was found to decrease liver total reduced glutathione and also fcrosomal glucose-6-phosphatase, and the results are discussed with reference to the anti- and prooxidant properties of plumberagin.
Abstract: Plumbagin was administered to rats at a concentration of 1,2,4,8 and 16 mg per kg body weight. After 24 h lipid peroxide levels were found to decrease in subcellular fractions of liver. Plumbagin inhibited ascorbate and nicotinafde adenine dinucleotide phosphate (reduced) dependent lipid peroxidation but was without any effect on cumene hydroperoxide dependent lipid peroxidation. Injection of 16 mg of plumbagin per kg body weight was found to decrease liver total reduced glutathione and also fcrosomal glucose-6-phosphatase. The results are discussed with reference to the anti- and prooxidant properties of plumbagin.