Showing papers by "Banaras Hindu University published in 1977"

Genetic control of heterocyst formation in the blue-Green algae Nostoc muscorum and nostoc linckia

Abstract: Non-heterocystous, non-nitrogenfixing (het- nif-), heterocystous, non-nitrogenfixing (het+ nif-) and multiple heterocystous, nitrogen-fixing (M-het+ nif+) mutants of heterocystous, nitrogen-fixing (het+ nif+) wild-type Nostoc muscorum and Nostoc linckia were isolated and characterized with respect to (a) nitrogenfixing activity, (b) reversion frequency, (c) ammonium repressibility of heterocyst formation, (d) heterocyst spacing pattern, and (e) action of L-methionine-DL-sulphoximine (MSO), an inhibitor of glutamine synthetase (GS), on heterocyst regulation. The mutant and revertant results suggest: (i) either involvement of a common genetic determinant in the formation of heterocyst and nitrogenase or the organization of het genes and nif genes in a single operon prone to complete inactivation by a single polar mutation, (ii) non-participation of active nitrogenase in regulation of heterocyst spacing; (iii) involvement of genetic factor(s) in the control of heterocyst spacing pattern in N. linckia, and (iv) apparently different nature of the mechanism of heterocyst inhibition by proheterocyst from that of heterocyst inhibition by NO 3 - or NH 4 + .

Complexes of copper(II) with nicotinic acid and some related ligands

Abstract: Coordination compounds of copper(II) chloride, bromide, thiocyanate and sulphate with nicotinic acid, nicotinamide and isonicotinamide have been prepared and characterized by molecular conductance, magnetic susceptibility, electronic and i.r. spectral measurements down to 200 cm−1 in the solid state. Possible stereochemistries for these complexes in the solid state are discussed.

Meiotic Behaviour of Spontaneous and Mutagen Induced Partial Desynaptic Plants in Pearl Millet

Abstract: Partial desynaptic plants were isolated from normal population of pearl millet (Pennisetum typhoides S. and H.) inbred T55 and mutagen (EMS and gamma-rays) treated populations of inbreds Tif23A, Tif23B and K560. The pachytene pairing was complete and normal. A variable number (2-14) of univalents occurred at MI. Anaphase I separation was normal in the majority (66-79%) of the cells; many showed 8:6 and 9:5 chromosome separation. The spontaneous desynaptic plant showed laggards and chromatin bridges at anatelophase I, while the induced ones did not show these aberrations. Chiasma frequency in the desynaptic plants was lower than that in the normal controls.

Histochemistry of the unicellular glands in relation to their physiological significance in the epidermis of Monopterus cuchia (Synbranchiformes, Pisces)

Abstract: The cytochemical nature of the secretory contents of the unicellular glands—the mucous cells and the sacciform granulated cells in the epidermis of Monopterus cuchia has been described in order to understand their physiological significance. The mucous cells secrete mainly the acid mucopolysaccharides and mucoproteins in addition to small amounts of phospholipids. The secretory contents of the sacciform granulated cells are proteinaceous in nature and give strong reactions for elastin, tryptophan and tryosine. High amounts of cholesterol and small amounts of phospholipids and acid mucopolysaccharides are also identified in these sacciform granulated cells. Phospholipids, mucoproteins and elastin could well increase the viscosity of mucopolysaccharides retaining the slimy secretions on the surface for relatively longer periods. The retention of mucopolysaccharides and elastin on the surface for longer periods that can bind large amounts of water has been correlated to keep the skin moist, facilitating the cutaneous respiration and preventing the fish from desiccation when it is on land. The role of elastin in protecting the fish from various chemical attacks and mechanical stresses is also discussed. Tryptophan secreted by sacciform granulated cells may have the immunological role facilitating the antibody transfer across the epidermis.

Conductance studies in amide-water mixtures. II. Sodium salts inN,N-dimethylformamide-water mixtures at 35°C

Abstract: Conductance data for sodium nitrite, chloride, and acetate in water andN,N-dimethylformamide (DMF)-water mixtures (74.82≥D≥42.48) for the concentration range 0.001–0.04N, as well as the densities, viscosities, and dielectric constants of the solvent mixtures at 35°C, are reported. The data have been analyzed by the Fuoss (1975) equation. The existence of a maximum in the viscosity at a 1∶3 mole ratio of DMF and water is indicated. The Walden products for all the three salts pass through a maximum while the equivalent conductances show a minimum with increasing DMF content. The maxima in the Walden product are attributed to the dehydration of ions by the cosolvent (DMF).

On the formation of the diamond grain configuration during high temperature creep and fatigue

Abstract: A study has been made of the influence of test variables on the formation of the diamond grain configuration during high temperature creep and fatigue deformation of a wide variety of metals. The proposed mechanisms for the formation of this interesting grain morphology are reviewed. It is concluded that the diamond grain configuration arises from a balance between grain-boundary sliding, grain-boundary mobility, intragranular deformation and defect imbalance across the grain boundaries and that it tends to be stabilized by intergranular cavitation. While the phenomenon occurs during high temperature fatigue in a variety of metals irrespective of their crystal structure, during creep it has been observed only in to h c p metals. It is surmised that the occurrence of the diamond array of grain boundaries during creep deformation in h c p metals is aided by the limited number of slip systems which leads to high defect imbalances in adjacent grains and consequently high driving forces for grain-boundary migration. On the basis of quantitative metallography involving measurements of the number of edges per grain section, the number of grains meeting at vertices, angular distribution histograms and grain-boundary lengths in different angular orientations with respect to the stress axis in "annealed" and "diamond" microstructures, it is concluded that the shape of the "diamond" grain is essentially the same as that of the "annealed" grain but in a distorted form.

Competition from weeds and their control in direct‐seeded rice

Abstract: Summary: In direct-seeded upland rice (Oryza sativa L.) yield reductions due to weed competition ranged from 42 to 65% in field experiments conducted in eastern Utter Pradash, India. The most critical period, when crop losses due to weed competition were most severe, ranged from 10 to 20 days after emergence. Yields generally continued to increase, however, as the length of the weed-free period increased. The weed flora consisted of various grasses, sedges and broadleaved species. The most effective herbicide treatment evaluated was a pre-emergence application of alachlor followed by a post-emergence application of propanil or one mechanical weeding. Resume: Competition exercee par les mauvaises herbes et desherbage dans les cultures de riz en semis direct Dans des cultures de riz (Oryza sativa L.) en region montagneuse et en semis direct, les reductions de rendement provoquees par la competition des mauvaises herbes ont ete comprises entre 42 et 65% dans des essais au champ realises dans l'Utter Pradash oriental, en Inde. La periode la plus critique, lorsque les pertes de rendement dues e la competition des mauvaises herbes ont ete les plus severes, sest situee entre 10 et 20 jours apres la Ievee. Toutefois, les rendements ont generalement continueasaccroatre, a mesure qu'augmentait la duree de la periode sans mauvaises herbes. La flore adventice etait constituee par diverses gramines, des cyperacees et des esptees dicotyledones. Le plus efficace des traitements herbicides essayes a ete une application d'alachlore en preievee, suivi d'une application de propanil en postlevee ou d'un sarclage mecanique. Zusammenfassung Urtkrautkonkurrenz und Unkrautbekampfung in direktgesatem Reis In Feldversuchen die im ostlichen Utter Pradash (Indien) in direktgesatem Trockenreis durchgefuhrt wurden, betrugen die Ertragsverluste durch Unkrautkonkurrenz zwischen 42 und 65%. Die kritischste Periode in der die Ertragsverluste durch die Unkrauter am starksten auftrat, war die Zeit zwischen dem 10. und dem 20. Tag nach dem Auflaufen. Die Ertrage stiegen jedoch weiter an, wenn die Bestande mit zunehmender Dauer unkrautfrei gehalten wurden. Die Unkrautflora setzte sich aus verschiedenen Grasern, Seggen und dikotylen Arten zusammen. Die wirkungsvolls Herbizidbehandlung bestand in einer Vorauflaufspritzung mit Alachlor und einer Nachauflaufbe-handlung mit Propanil oder einer mechanischen Massnahme.

Isolation and characterization of chlorate-resistant mutants of the blue-green alga Nostoc muscorum

Abstract: Spontaneous chlorate-resistant (Clr) mutants of three classes were isolated from Nostoc muscorum under three different selective conditions. A Clr-N 2 class of mutants lacked nitrate reductase and showed nitrate inhibition of nitrogen fixation. A Clr-NO 3 group of het + nif − mutants formed heterocysts, but lacked nitrogen fixation and active nitrogenase enzyme. The Clr-NO 2 class included those mutants deficient in both active nitrogenase and nitrate reductase, as they were unable to grow at the expense of molecular nitrogen or with nitrate nitrogen. The results suggest a common genetic determinant of active nitrogenase and nitrate reductase in the blue-green alga N. muscorum .

Nicotinoyl hydrazide complexes of some first row transition metal ions

Abstract: Nicotinoyl hydrazide, L, complexes of the MLCl2 · n EtOH type [M = manganese(II), iron(ll), cobalt(II), nickel(II) and copper(II); n = 0 or 1], WL2) (NO3)2 [M = cobalt(II) and nickel(II)] and mixed metal complexes such as HgCo2 L2 Cl6 and (NiL2)HgI4 have been prepared and their nature and structure studied by molar conductance, magnetic susceptibility, electronic, e.s.r. and i.r. spectral measurements. Octahedral structures have been proposed for all the complexes except MnLCl2, CoLCl2 and HgCo2 L2 C16 for which tetrahedral geometry is suggested.

Copper(II) acetate and picrate complexes of sulfa drugs

Abstract: Copper(II) acetate and picrate complexes of sulfa drugsviz., sulfanilamide, sulfaguanidine, sulfathiazole, sulfadiazine, sulfamerazine and sulfamethazine were prepared and characterized with the help of analytical, electronic, i.r. and magnetic moment data. The complexes are paramagnetic, planar or mixed planar and octahedral, insoluble and melt (with decomposition) in the 185°–225° range. The sulfa drugs coordinate through their amino groups and the acetate or picrate ions are bonded to the metal through the -C(O)O group.

The occurrence of 12, 13-epoxytrichothecenes in seeds of safflower infected with Fusarium oxysporum f. sp. carthami.

Abstract: From the seeds of safflower (Carthamus tinctorius Linn.), infected with Fusarium oxysporum f. sp. carthami, 3 toxic compounds have been isolated in quantities sufficient to cause mycotoxicosis on prolonged ingestion. 2 of these have been identified as diacetoxyscirpenol and T-2 toxin, while the third one has also been partially characterized as a 12, 13-epoxytrichothecene. Additionally, the incidence of secondary fusarial infection of healthy seeds due to contamination with the infected ones has been reported for the first time.

Effect of soil burning on microfungi

Abstract: The qualitative and quantitative nature of microfungi in soil after burning was studied for seven months. The numbers of fungal species and their colonies in soil were reduced immediately after burning but returned to their normal state after about a couple of months. Species of Aspergillus and Penicillium were the first to colonize the burnt soil. Trichoderma viride appeared after two months. Penicillium spp. decreased consistently with time whereas T. viride followed the reverse path. Several other species appeared in due course as and when ecological conditions became suitable for them. re]19760720

Synthesis and structural studies of some first row transition metal complexes of acetone nicotinoyl hydrazone

Abstract: Acetone nicotinoyl hydrazone (ANII) complexes of the types M(ANH)Cl2 · nEtOH and M(ANH-H)2 H2O (where M = MnII FeII, CoII, NiII, CuII or ZnII and n = 0,1 or 2) have been prepared and their structures studied by molar conductance, i.r. and electronic spectra, and room temperature magnetic measurements. All the complexes arc nonionic in a 0.001 M solution of formic acid. Magnetic and electronic spectral studies show that all the complexes are spin-free regular or distorted octahedra except Mn(ANH)Cl2 and Co(ANH)CI2 which are tetrahedral. The distorted octahedral geometry of Cu(ANH-H)2 · H2O has also been confirmed from its sold state e.s.r spectrum at 77 K. From i.r. spectral studies, ANH has been found to act as a tridentate ligand in all the complexes except Mn(ANH)Cl2 where it behaves as a bidentate ligand.

Effects of Some Growth Substances on Mitosis

Abstract: Cytological effects of three growth substances namely, Gibberellic acid (GA), Indole-butyric acid (IBA), and 2, 4-Dichlorophenoxyacetic acid (2, 4-D) were studied on root tip mitosis of Vicia faba treated with 10 and 50 ppm concentrations and 3, 6 and 12 hours durations. GA enhanced cell division while 2, 4-D and IBA inhibited it and were more toxic than GA. Main effects at chromosomal level were chromosome breakage, bridge formation, C-mitosis, micronuclei formation, stickiness and chromosome condensation.

Propagation of Sonic Waves in Radiating Gases

Abstract: The paper discusses the propagation of a sonic discontinuity in a radiating gas. The velocity of propagation is determined and it is shown that the velocity of propagation of the sonic discontinuity is not influenced by the radiative heat transfer under thin gas approximation. The fundamental differential equations governing the growth of the sonic discontinuity are obtained and solved. It is concluded that if the sonic discontinuity is a compressive wave of order 1, then it terminates into a shock wave after a critical time tc which has been determined. But on the other hand, if it is an expansion wave of order 1, it will decay and be damped out ultimately. Particular cases of plane and spherical wave fronts have been discussed in details.

Transformation of dipole to schlumberger sounding curves by means of digital linear filters

Abstract: Linear relationship between dipole and Schlumberger sounding resistivities leads to the use of digital filters to transform the former to the latter. This transformation is of importance from the viewpoint that Schlumberger interpretational techniques and know-how could then be applied to the pseudo-Schlumberger field curve. Filters for this transformation are presented for the radial, perpendicular, and parallel (30°) dipole method. The characteristics of these filters are similar to the ones for transforming dipole data to the kernel and are favourable in that they do not amplify noise. A sampling interval of (In 10) /6 has been used in determining the filter yielding good accuracy. Like previous filters the present one is handy and fast in operation.

N-benzamidosalicylaldimine complexes of copper(II), nickel(II), cobalt(II), iron(II), manganese(II), oxyvanadium(IV) and oxytitanium(IV)

Abstract: N-benzamidosalicylaldimine (H2L) complexes of CuII, NiII, CoII, FeII, MnII. VOIV and TiOIV have been prepared. The ligand probably coordinates to the metal from the hydroxyl, carbonyl and imino groups.

Sulfadrug complexes of zinc(II), cadmium(II) and mercury(II)

Abstract: ZnII, CdII and HgII complexes of sulfadrugs,viz., sulfathiazole, sulfadiazine, sulfamerazine and sulfamethazine were prepared and characterized by analytical and spectroscopic data. The complexes are insoluble and melt with decomposition. The drugs act as bidentate ligands yielding polymeric complexes except for the ZnII(sulfamethazine) complex in which the drug is monodentate.

Effect of sectioning the prothoracic gland nerves in the larva of the lemon-butterfly, Papilio demoleus L

Abstract: Sectioning the nerves innervating the prothoracic glands of the larva of the lemon-butterfly has no effect on the development and metamorphosis of the insect. The results are discussed in the light of the known facts.