Search

Present investigation looks into the effect of ferrite grain size on ratcheting behavior of 0.14% carbon Nb-bearing microalloyed steel. Ferrite grain size has been varied by annealing treatment at 925, 1000, and 1075°C for one hour. Ratcheting behavior of the steels has been studied by asymmetrical cyclic stressing for 500 cycles at three different mean stresses, 5, 10, and 15% yield stress, but keeping the stress amplitude fixed at the yield stress level, corresponding to the respective ferrite grain size. It is observed that with increase in ferrite grain size final ratcheting strain decreases. Further, with increasing mean stress higher ratcheting strain develops in the specimens irrespective of grain size. It is also observed that while ratcheting strain with number of cycle follow different pattern depending upon ferrite grain size, the variation of maximum ratcheting strain with mean stress obeys a linear relationship for all the grain sizes. Effect of ratcheting on subsequent Low cycle fatigue (LCF...

Papaya (Carica papaya L.) is a heavy feeder of nutrients. To maintain the continuous growth and fruiting, heavy doses of fertilizers should be applied at frequent intervals which may lead to unsustainability of the present day agricultural system causing soil deterioration and environmental pollution. Hence, there is a need to shift from conventional nutrient management system to integrated nutrient management system. As the biofertilizers are the essential components of integrated nutrient management, an investigation was conducted at Horticulture Research Station of Bidhan Chandra Krishi Viswavidyalaya, Mondouri, Nadia, West Bengal to study the efficacy of PSM (Bacillus megatherium + Aspergillus awamori) and VAM (Glomus mosseae + G. fasciculatum) biofertilizers with graded levels of phosphorus (P 2 O 5 at 50, 100, 150 and 200 g) on growth and nutrient uptake of papaya. Maximum plant height (192.67 cm), girth (24.00 cm) and total number of leaves (25.17) were observed in VAM + 200 g P 2 O 5 . VAM were also found more effective in increasing height and girth than PSM. Early flowering was noticed due to application of increased phosphorus level and biofertilizer inoculation. Highest yield (64.85 tonnes/ha) was resulted due to the inoculation effect of PSM and 200 g P 2 O 5 treatment combination. P and K content of leaves increased with increasing phosphorus level and biofertilizer application.

Streptomyces venezuelae P(10) could produce extracellular chitinase in a medium containing 0.6% colloidal chitin that was fermented for 96 hours at 30 degrees C. The enzyme was purified to apparent homogeneity with 80% saturation of ammonium sulfate as shown by chitin affinity chromatography and DEAE-cellulose anion-exchange chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of the enzyme showed a molecular weight of 66 kDa. The chitinase was characterized, and antifungal activity was observed against phytopathogens. Also, the first 15 N-terminal amino-acid residues of the chitinase were determined. The chitin hydrolysed products were N-acetylglucosamine and N, N'-diacetylchitobiose.

ZnO films doped with different concentrations of aluminum (AZO) have been prepared by the sol-gel technique. The electrical properties of the samples have been measured on as-deposited films. Two of the films have been heat treated in vacuum at 400 °C to determine the changes in transport properties. The electrical properties, i.e. conductivity and Hall coefficient, have been studied from room temperature down to low temperatures. Combining these two it has been possible to determine the Hall mobilities, carrier concentrations and the barrier height at the grain-boundary region. Attempts have been made to explain the barrier height assuming monovalent trapping states at the grain boundary and the density of trapped states has been estimated from the experimental data. As carrier concentration increases after heat treatment of the samples in vacuum the role of non-ionized impurities decreases.

The optical transmission and reflection data for aluminum doped zinc oxide films have been analyzed. The optical absorption coefficient ( α ) and hence the refractive index ( n ), extinction coefficient ( k ) and the band gap ( E g ) have been determined for these films using different methods. The films are prepared by sol–gel technique and are optically transparent. It is observed that the band gap increases with aluminum doping from 3.19 to 3.24 eV, but is less than the bulk ZnO crystal. A qualitative explanation has been put forward for the band gap widening with doping. The width of the band tail states which is connected to localized states in the band gap is least for 1 at% doped aluminum film. The porosity of the films as deduced from the refractive index seems to be of the same order in all the cases, but relatively higher for 1 at% aluminum doped films.

A field experiment was conducted to study the effect of arbuscular mycorrhizal association in mulberry saplings var. S1, together with two levels of phosphate, on growth characters, leaf yield and phosphorus uptake. The experiment was conducted in the period 1995 to 1997 at the Technical Service Centre, Kashipur, Purulia (West Bengal) under rainfed, lateritic soil conditions. Pooled data analysis revealed that there was no significant variation among the treatments in most of the characters except height of plant and leaf moisture percentage. Plant height in both treatments with Glomus mosseae was significantly less than in the others, while there was significant reduction in moisture percentage in G. fasciculatum with 25 kg of phosphate and G. mosseae with 10 kg of phosphate ha–1 year–1 than in other treatments. There was no significant season–treatment effect on any of the parameters. Considering all the quantitative and qualitative characters, G. fasciculatum together with the most economic dose of phosphate showed more promising performance than G. etunicatum and G. mosseae with different doses of phosphate fertilizer. At 80% of the recommended dose of inorganic phosphate fertilizer, Rs 534.0 were earned as net profit.

Elevated plasma Homocysteine level is an independent risk factor for age related (senile) cataract. Certain nutritional deficiencies, in particular Folate, Vitamin B(12), Vitamin B(6) relate inversely with Homocysteine level. This study was undertaken to evaluate the plasma level of Vitamin B(12), Folate, and Homocysteine of cataract patients and to study the interplay between them. Serum Homocysteine level is significantly increased in cataract patients when compared with control (p0.001). There was a significant decrease in the level of Folate as compared with control (p0.001). There was a negative correlation between Homocysteine vs. Vitamin B(12) (p0.01) and Folate (p0.01) in the Cataract patients. Our findings suggest that increased plasma Homocysteine level is associated with decreased plasma levels of Folate and VitaminB(12) in Cataract patients, which might have a possible role in the root cause of cataract pathogenesis.

Generally, the failure of major machinery parts is due to fatigue damage. Because of the structural inhomogeneity of metals, fatigue damage may sometimes occur significantly below the yield strength of the material due to microplastic deformation at low stress levels. Commercial En-8 grade steel (widely used for making secondary metalworking products) was used to estimate the fatigue damage response during cyclic loading nearer to the fatigue endurance limit. Estimation of fatigue damage was carried out with the aid of a nondestructive testing (NDT) method, that is, Elastosonic measurement of fatigue damping coefficient and slope of fatigue damping curves. Results indicate that fatigue damage increases in annealed En-8 steel with an increase in peak stress and with an increase in the number of cycles. However, for hardened and tempered En-8 steel, experimental results may not provide a true indication of fatigue damage during fatigue loading nearer to the endurance limit, most likely due to the more homogeneous structure. Generally, fatigue failure occurs in this grade of steel due to microcrack generation in the cementite of the pearlite phase of annealed steel.

Localized swelling has been observed in 24Cr-24Ni-Nb steel transportation rollers used in the normalizing furnace of a plate mill after prolonged service at high temperature. Due to high localized thermal and mechanical stresses, the chromia layer formed on the roller surface ruptures, exposing the roller substrate to furnace oxygen. Oxidation of second-phase carbides results in the formation of carbon monoxide at very high partial pressure. This leads to formation of voids, leading in turn to localized swelling of the roller material.

Actual nitrogen fixation of root nodules of differentAlbizia-rhizobium symbioses, was compared with the potential nitrogen fixation of isolated bacteroids. The potential nitrogen fixation exceeded actual nitrogen fixation in all symbionts. After addition of nitrate the actual nitrogen fixation decreased more than did potential nitrogen fixation in effective symbiosis, whereas in a less effective symbiosis, the actual and potential nitrogen fixation increased as a result of better photosynthate supply to the roots and nodules. As confirmed by correlation analysis, the nitrogen fixation and photosynthetic yield of suboptimum symbioses were relatively enhanced by dressing with inorganic nitrogen fertilizer.

The agar gel double diffusion test was evaluated for detection of nuclear polyhedrosis virus infecting the silkworm, Bombyx mori L. (BmNPV). The test was successful using alkali-dissolved BmNPV as antigen. The antiserum raised against dissolved BmNPV gave positive results with a wider range of antigenic concentrations compared to antiserum raised against undissolved BmNPV. Gel plates prepared using phosphate buffered-saline as dissolving medium for agarose gave sharper and clearer precipitation bands compared to those made with sodium carbonate-saline as diluent. Sharp bands were obtained when the experiment was carried out at 25°C, whereas at higher temperature (35°C), the bands were diffused. The test was able to detect antigen concentration as low as 2 × 106 OBs/ml (18.9 μg/ml of antigen protein).

Jute fiber was grafted by acrylonitrile and methylmethacrylate monomers in raw and bleached condition. It was also noted that optimum grafting takes place after about 4 h of grafting. It was also noted that in bleached jute fiber, the grafting percentage is higher at all stages of grafting but the tenacity value at the highest add-on is practically the same as that of raw fiber with much less add-on. The crystalline orientation of the grafted jute fiber was correlated with the fiber tenacity. The moisture regain (%) of the fiber after grafting showed a decreasing trend with an increase in grafting percentage. No structural change of the fiber occurred due to grafting. © 1995 John Wiley & Sons, Inc.

Large size single crystals of undoped and Ce doped Li6Gd(BO3)3 oriented in direction have been grown using the Czochralski technique. The Transparency of these crystals was >85%. The Low temperature photoluminescence study of these crystals revealed that the temperature quenching of Ce3+ emission is compensated, to some extent, by an increased energy transfer between Gd3+ →Ce3+ with temperature.

Despite the prevalence of starch-hydrolyzing enzymes in bacilli, relatively few have been studied in detail. In an attempt to isolate an effective α-amylase-producing strain, Bacillus globisporus BH-1b has been isolated. The strain requires few nutritional supplements and shows induction in the presence of galactose. 2% potassium nitrate and pH 7.2 emerged as optimum for the fermentation medium. The durability of the enzyme has also been tested at a low pH and a high temperature.

Raw and partially delignified jute fibers were grafted with acrylonitrile and methyl meth-acrylate monomers, using the redox system of initiation with ceric ammonium sulfate. Grafting was also carried out in a mixed monomer system with acrylonitrile and methyl methacrylate monomers in different proportions. The optimum grafting condition depends on the duration of grafting treatment and proportion of grafting monomers. The monomers entered the fiber matrix with high add-on and, at still higher graft add-ons, the ultimate fibers suffered disintegration. The surfaces were increasingly covered with grafted materials and longitudinal cracks developed on the fiber surface with higher add-on. © 1993 John Wiley & Sons, Inc.

Jute stick was treated with white-rot fungus for incubation periods of 6 days (MBA) and 12 days (MBB). The infrared spectra of fungus treated samples (MBA and MBB) and control jute stick (MBC) were analyzed and compared. The bands attributed mainly to hemicellulose show an increase in absorbance intensity ratios (A v /A 2900 ) with increaae of incubation time. Similarly the bands attributed to lignin show an increase in the absorbance intensity ratios with increase of incubation time. Increase in the intensity of 1635 cm -1 band with increases of incubation time was observed.

Thyroid stimulating hormone (TSH), Free Thyroxine (FT(4)) and Free Triiodothyronine (FT(3)) were assayed in 505 women of this region. 60 women had previous history of thyroid disease. The remaining 445 women formed the "Disease free group". A "Reference group" was obtained by excluding women with previous and present history of thyroid dysfunction. Of the total 505 women examined 15.8% had thyroid dysfunction and 84.2% were euthyroid. 11.5% were hypothyroid (9.5% sub-clinical) and 1.8% hyperthyroid (1.2% clinical). The geometric mean TSH for the total population was 2.65 μIU/ml. It was significantly (p=0.025) lower in the reference population 2.17 μIU/ml. There was no significant difference in the FT(3) and FT(4) values between groups. 19% of women over 60 years had elevated TSH above 4.5 μIU/ml. The 2.5 and 97.5 percentiles of the reference population was 1.1-5.2 μIU/ml. 6.1% of women in the reference group had TSH levels above the reference intervals. Hypothyroidism particularly sub-clinical hypothyroidism is predominantly present amongst women in this iodine sufficient region. Evaluation of thyroid status could help in early detection and treatment.

Jute stick was bleached with sodium chlorite and alkaline hydrogen peroxide solutions. The infrared (IR) spectra of bleached samples and jute stick were analyzed and compared. The bleached samples were characterized by higher absorbance intensity ratios (Av/A2900) of the bands attributed to hemicellulose. Among the bleached samples the chlorite-bleached sample showed higher intensity for the bands mentioned. The bands attributed to lignin are either absent or very weak in the chlorite-bleached jute stick as compared to that of peroxide-bleached jute stick, although some residual lignin was present in the substrate. The 1635 cm−1 band attribute to the vibration of adsorbed water molecules in the noncrystalline regions in cellulose appears as a sharp peak in chlorite-bleached jute stick and as a shoulder in peroxide-bleached jute stick. This can be attributed to the difference in the nature of the two bleaching processes.

We have undertaken a fundamental study of heterodiffusion of foreign ions in pure single crystals. The present work describes the measurements of the diffusion coefficient of monovalent cations in some alkali halides, namely Na+ and Rb+ into KCl, KBr, NaI and KI. The priority is given to the super-accuracy of the experimental data. The target is to test the validity of the existing theories for calculating the enthalpy and entropy of migration.

Defatted jute stick was treated with sodium hydroxide solution (2% w/v) at ambient temperature (∼ 32∼C) and boiling water bath temperature (95–97°C). Infrared (IR) spectra of defatted jute stick and alkali-treated jute stick were studied. The IR spectra of the alkalitreated jute stick were conspicuous by the absence of the 1730 cm−1 band, as compared to that of jute stick. Another characteristic feature of the alkali treated jute sticks is the absence of the band at 1240 cm−1, which is replaced by the 1265 and 1225 cm−1 bands; other bands in the above samples also recorded significant changes.

The infrared spectra of alkaline jute stick have been discussed and compared to that of untreated and control sample. A higher shift in the OH and lower shift in the CH stretching frequencies were observed in alkaline sample. The presence of a strong band at 1440–1430 cm−1 may be due to the coupling of COO− frequency with CH2 deformation frequency. The CO stretching mode at 1240 cm−1 disappears on alkaline treatment with the formation of new peaks at 1265 and 1225 cm−1. The β−glucosidic band at 895 cm−1 is shifted to 880 cm−1 with doubled intensity in alkaline jute stick.

Background. Microbial and fungal cellulases are known to hydrolyse cellulose, which is ingested as plant mate rial by herbivorous/omnivorous fishes. Microbial enzymes have enormous advantage of being produced in large quantities by established fermentation techniques. The present investigation aims to optimize the environmental and nutritional parameters for fermentation to enhance cellulase production by two bacterial strains isolated from fish gastrointestinal tracts. Materials and methods. Two bacterial strains, Bacillus subtilis CY5 and Bacillus circulans TP3, isolated from the gastrointestinal tracts of common carp, Cyprinus carpio L., and Mozambique tilapia, Oreochromis mossam bicus (Peters, 1852), respectively were identified as potent cellulase producers. Both strains were cultured in tryp tone soya broth for 24 h at 32 ± 2oC, when average viable count of 9.75 · 10 7 cells · mL –1 culture broth was obtained. This was used as the inoculum for the production medium. The fermentation medium was seeded with 1.0%, 2.0%, 3.0%, 4.0%, and 5.0% inoculum (tryptone soya broth) and incubated in static culture at 40oC to stan dardize the inoculum size for fermentation. The effect of different production parameters, such as fermentation condition, moisture, pH, temperature, inoculum size, and nitrogen sources on cellulase production by the isolat ed bacterial strains were studied. Results. Cellulase yield was highest (26 U in B. subtilis and 20.2 U in B. circulans ) in solid-state fermentation (SSF). Enzyme production in both the isolates increased in an optimum pH range of 7.0 to 7.5. Minimum cellulase production was observed at 45oC, while maximum production was obtained at 40oC. To standardize the fermenta tion period for cellulase production, production rate was measured at 12-h intervals up to 120 h. Enzyme produc tion increased for 96 h of fermentation in both strains, and decreased thereafter. The enzyme production increased with increased inoculum size up to 3.0 percentage points. Asparagine as the nitrogen source was most effective in B. subtilis CY5, while beef extract proved useful in optimizing enzyme production by B. circulans TP3. Conclusion. The results of this study will help to standardize the requirements for optimum production of cellu lase by cellulase-producing fish gut bacteria and might contribute towards better fish feed formulation incorpo rating plant ingredients, especially in the larval stages when the enzyme system is not efficient .

—Silkworm larvae infected transovarially with Nosema bombycis were fed with an aqueous suspension of Bavistin (50% carbendazim w/w) at 2 and 3% concentrations. The treatments increased the survival of worms and reduced the pebrine infection in the lot significantly, although complete elimination of infection was not observed. Significant beneficial effects of the treatments at 2 and 3% were also observed with respect to larval, cocoon and cocoon shell weights and cocoon to shell ratio. However, treatments with Bavistin at 4% concentration produced an adverse effect on cocoon characters.

Two trace elements, copper (Cu) and zinc (Zn) in serum are elevated in cancer patients since both areconstituents of super oxide dismutase (SOD) as metalloenzyme, the enzyme that scavenge free radicals andactivated oxygen species in the body. The study of 52 cancer patients comprising of 31 carcinoma stomachand 21 breast cancer showed the elevation of both of these trace elements in serum when compared to 32healthy controls and effected the kidney functions as a consequences. Serum Cu and Zn were estimated byAtomic Absorption Spectrometer (AAS), analyzed statistically by student "t" test and marked elevationwas observed in cancer patient compared to healthy controls. Serum Cu and Zn values were 98.13 ± 17.49μg/dl 99..57 ± 13.91 μg /dl respectively in 38 healthy subjects and these trace metals were 156.23 ± 31.02 μg/dl and 171.86 ± 35.15 μg/dl in 52 cancer patients showing significant elevation (P

A soil isolate of Bacillus stearothermophilus was found to synthesize thermostable alpha-amylase. The enzyme was purified to homogeneity by ammonium sulfate fractionation and IECC on DEAE-cellulose column. The purified enzyme was considered to be a monomeric protein with a molar mass of 64 kDa, as determined by SDS-PAGE. The enzyme showed a wide range of pH tolerance and maximum activity at pH 7.0. The temperature tolerance was up to 100 degrees C with more than 90% catalytic activity; the maximum activity was observed at 50 degrees C. Divalent metal ions exhibited inhibitory effect on the enzyme activity. However, proteinase inhibitor did not react positively.

Degraded gum, obtained from the waste liquor after degumming of decorticated ramie with hot dilute alkali, can replace one-third of the urea-formaldehyde resin required for making jute-stick particle board.

Microorganisms are the dominatign inhabitants of the soil, and there is an icnreasing tendency to apply heavy metals in agricultural practice. The ecological balance may be distrubed unknowingly if we do nogt measure the tolerance by the microorganisms of these heavy metals. It has been found in a Oscillatoria model system that widely used heavy metals have a high degree of toxicity to this cyanobacter.

The elastic scattering of photons from excited state configurations of carbon atoms and ions is considered, using the S–matrix approach, for configurations involving varying numbers of K and L electrons, with any remaining electrons being placed in an outer ( N ) shell. Situations where the scattering cross section is much larger or smaller than that for the ground state configuration are identified.

Les resultats du greffage de fibres brutes et blanchies montrent que l'acrylonitrile est greffe sur la lignine et la cellulose

A hydrocarbon utilizing strain of Micrococcus varians 2Fa isolated from local soil has been found to yield lysine 2.6 g l −1 . Addition of B-vitamins and trace elements to the optimal media, has been found to stimulate growth and enhance lysine yield

The lattice statics method has been used for relaxation calculations in lead due to a vacancy created in the lattice. Using the measured phonon dispersion relations and the elastic constants as constraints the dynamical matrix is derived considering progressively the interactions up to seventh neighbour. The calculation shows that the first twelve neighbours relax towards the vacancy whereas the second six relax outwards. In general, the displacements are found to be larger in the close-packed directions. The divacancy binding energy is found to be in accordance with other calculations and the bond model. The formation energy of the monovacancy is also found to be very close to the experimental value.

The diffusion of nickel into copper and copper–nickel alloys are investigated in the temperature range of 780 to 1037 °C by the resistometric method and the diffusion coefficients and activation energies are obtained. The nickel diffusion in copper is compared with the previous studies. For the diffusion of nickel into copper–1.08 at% nickel and copper–2.81 at% nickel alloys no such comparison can be made as there are no data available in this dilution range. The diffusion coefficients of the systems studied show a strong dependence on the alloy composition. It is also observed that addition of nickel into copper retards the diffusivity. The data obtained from the studies are analysed in the light of the theories of LeClaire and Neumann and Hirschwald.

The reactions of bis(acetylacetonato)oxovanadium (IV) hydrate, VO(acac)2H2O, with different chelating ligands (containing at least one NH2 group) have been studied. In dry refluxing toluene, heterochelates of the type [VO(acac)(Lsbnd;L)]0(or+)·nH2O (where LL = neutral or monoanion of bidentate chelating ligands; n = 0–1) have been isolated. On the other hand, dibasic tridentate (LH2) or dibasic tetradentate (L′H2) Schiff bases replaced all the acetylacetonate anions from VO(acac)2H2O to produce VO(L)H2O or VO(L′) in refluxing toluene or ethanol. Analogous reactions of VO(acac)2H2O with aminoacids, aminoalcohols, semi- and thiosemi-carbazide in ethanol, methanol, water-ethanol or water-acetone mixture, produced a variety of mixed ligand complexes of oxovanadium(IV) ion involving Schiff bases, many of which show subnormal magnetic moments at room temperature. In the course of this study several mixed ligand oxovanadium(IV) complexes with neutral acetylacetone (or glycine) have also been isolated. The reactions of VO(acac)2H2O with chelating amino ligands in presence of even trace amount of water invariably result in the template syntheses of Schiff base chelates, which has been discussed qualitatively The electronic spectra of these chelates have been interpreted with the help of either C2V or C4V local symmetry. The elemental analyses, i.r. spectral data and cryomagnetic data have also been used to characterise the complexes.

DNAs have been isolated from various Oryza species and studied using physical techniques. The percent of guanine plus cytosine has been determined by thermal denaturation. While the base composition varied between the species, no heterogeneity in the base pair distribution was observed. Renaturation kinetics data of DNAs from different species show that the proportion of repeated DNA sequences vary considerably depending on the DNA content per cell, whereas the nonrepetitive DNA component remains relatively constant. These results suggest that in addition to a small range of DNA variation between the species, changes in the base composition and proportion of repeated sequences have accompanied divergence of the species within the genus.

Theoretical studies of Rayleigh scattering of photons from neon atoms with different degrees of ionization, for energies both below and above the K-edges of the ions, are presented. Some unexpected structures both in Rayleigh scattering and in photoionization from neutral and weakly ionized atoms, very close to threshold, have been reported. It has recently been realized that some of the predicted structures may have a nonphysical origin and are due to the limitation of the independent-particle model and also to the use of a Coulombic Latter tail. Use of a K-shell vacancy potential — in which an electron is assumed to be removed from the K-shell — in calculating K-shell Rayleigh scattering amplitudes removes some of the structure effects near threshold. We present in this work a discussion of scattering angular distributions and total cross sections, obtained utilizing vacancy potentials, and compare these predictions with those previously obtained in other potential models.

The diffusion of tin in lead has been studied in the temperature range 195–322[ddot]C by the resistometric method. An Arrhenius relation is found to be obeyed. The values of activation energy and diffusion coefficient agree well with the earlier values determined by the radioactive tracer technique. An attempt has been made to interpret the data in the light of pseudo-potential theory using two different potentials and different exchange and correlation functions. The effect of exchange and correlation have been incorporated and the effect of relaxation of the neighbours at the activated position of the impurity atom during migration was taken into account. The calculated value of ΔQ, namely the difference between the activation energies of impurity and self-diffusion, seems to depend on the form of potential and exchange correlation chosen although the sign of ΔQ is reproduced in all cases.

Twenty-three newly synthesized mixed-ligand complexes of oxo-vanadium(IV) and oxo-vanadium(V) were studied for antimicrobial activity. Eight of these complexes were found to have microbicidal properties. The complexes [NH4][VO(gl)2]H2O (gl-H2 = glycolic acid) and [VO(ACOAP)(acac-H)]H20 (ACOAP-H2=Schiff base of acetylacetone and orthoaminophenol, acac-H=acetyl-acetone) show broad bactericidal spectra, while the complexes [VO(ACSAM)2]OH (ACSAM-H = Schiff base of acetylacetone and sulphanilamide) and [VO(CSSAM-H)2]H2O (CSSAM-H =Schiff base of 3-carboxy salicylaldehyde and sulphanilamide) possess pronounced antidermatophytic properties. The latter is inhibitory to plant pathogenic fungi as well. Plant tumour producing Agrobacterium tumefaciens is effectively inhibited in vitro by the complex [VO(ACTSC-Na)(acac)]H2O (ACTSC-H2 = condensation product of acetylacetone and thiosemicarbazide). Minimum inhibitory concentrations of all the active complexes are within the values of 0.125-2.00 mg/ml. Out of the 7 active complexes tested for 50% inhibition of conidial germination of Helminthosporium oryzae, a rice plant pathogen, only 1 complex, viz. [VO(acac) (ACACAACD)] (ACACAACD(H)NH4 equal Schiff base of acetylacetone and ammonium 2-amino-1-cyclopentene-1-dithiocarboxylate) shows a positive result. The effective concentration is 0.55 mg/ml. Three vanadium complexes were tested for insect sterilant and ovicidal properties on the red cotton bug, Dysdercus koenigi. The complex [VO(HASA-Na) (acac)]H2O (HASA-H2 = Schiff base of orthohydroxyacetophenone and anthr anilic acid) was found to be a suitable male sterilant.

In vitro culture ofBrassica alba anthers on a growth medium containing inorganics of KB5 and organics, iron, sucrose and hormones of B5 resulted in a very high response of anthers (93.75%) towards callus induction. All the calli transferred to regeneration media responded favourably even after six months of callus induction. Numerous torpedo-shaped embryoids developed in clusters at many sites from each callus mass. Secondary embryogenesis and multiple shoot formation was also observed in many cases. The number of embryoids and plantlets produced by one embryogenic anther were as high as 169.8 and 17 respectively. 87% of the regenerated plants were haploids.

Activity of DAP-decarboxylase in lysine overproducing strains of Micrococcus luteus, M. varians and Arthrobacter globiformisLb reached the highest level during the end of the exponetial phase of growth and remained at the same high level during the stationary phase of growth when major bulk of lysine was accumulated. In comparison in a lysine non-producing strain of Arthrobacter globiformis I 4 the activity of the same enzyme was low. DAP-decarboxylase of these three lysine overproducers has two specialities, persistence during the stationary phase and insensivity to repression by exogenous lysine.

A glucomannan, isolated by fractionation of the alkali-soluble hemicelluloses of sunn-hemp fibre (crotalaria juncea linn), had [α] -45° and, on hydrolysis, yielded glucose, mannose, and xylose in the molar ratios 1.2:1:0.07. The methylated polysaccharide contained an average of ≈45 hexose residues, whereas the corresponding value for the nitrate derivative was 49. Structural studies showed that the glucomannan has a main chain of (1→4)-linked β-D-glucopyranosyl and -mannopyranosyl residues. The molecule appears to have an average of one branch point, through position 6 of both glucose and mannose residues of the main chain. Both D-glucopyranosyl (87%) and d-mannopyranosyl (13%) residues were present as non-reducing end groups. D-glucose and d-mannose occur in the chain both as alternate and contiguous units.

The diffusion of tin in copper and lead in silver has been studied by the resistometric method, using the step annealing procedure of Ceresara et al. The impurity diffusion coefficient D2 and activation energy Q2 are determined for the systems under consideration. The values thus obtained are in fairly good agreement with those obtained by earlier studies using radioactive tracer and X-ray techniques. The data are interpreted in terms of the electrostatic theory for impurity diffusion in metals.

A hydrocarbon utilizing strain of Arthrobacter globiformis Lb isolated from local soil has been found to yield lysine 3.4 g l−1, keeping the medium optimal for pH, C- and N-sources. Addition of antibiotics and micronutrients to that optimal media stimulated cell growth and enhanced lysine yield.

SUMMARYNuclear DNA syntheses have been measured microspectrophotometrically in course of meiotic nuclear development inNeurospora crassa. The purpose of the study has been to establish the timing of these DNA syntheses in relation to meiosis and in the formation of its final products in an ideal genetic material, where the products of the meiotic division can be recovered and identified. Spectrophotometric analysis has indicated that the last premeiotic DNA replication is completed before caryogamy; a postmeiotic DNA replication takes place at the tetrad of the nuclei level; and finally a second postmeiotic DNA replication occurs in the ascospores to result in eight binucleated ascospores. The timing of postmeiotic replication is compatible with the models explaining gene conversion through the postulated mechanisms involving heteroduplex formation.

Regeneration of rice plantlets (Oryza sativa L.) from calli originated from leaf sheath cells was made possible. This was possible in tissues initially grown in media containing 2.4-D (2.4-dichlorophenoxyacetic acid) at low temperature and illumination. The slow growing tissues were subsequently subjected to growth conditions at an elevated temperature and higher illumination with addition of kinetin and IAA and without 2.4-D. The suitability of leaf sheath cells for protoplast technology is indicated by this success.

Significant differences have been observed in the steady-state permeation of gases through symmetric and asymmetric (Loeb-type) cellulose acetate membranes. The studies were made with O2, N2, Ar, Kr, Xe, and CO2 in the temperature range from -5 to 85°C and at subatmospheric pressures. The differences in permeation behavior may reflect structural differences between the symmetric membranes and the dense surface layer (“skin”) of the asymmetric membranes. The overall mechanism of gas permeation through the symmetric membranes appears to be one of “solution-diffusion,” similar to that observed with many other nonporous polymeric membranes. In the case of the asymmetric membranes, this mechanism is probably modified by the presence of micropores or other imperfections in the dense surface layer. Cellulose acetate exhibits two second-order transitions in the presence of the penetrant gases, one between 60 and 70°C and the other near 15°C. The transitions were observed with both types of membranes.

The results of treatment of meiotic cells of Lilium longiflorum by cycloheximide at the time of chiasma initiation and formation suggest that in the sequential phases of nuclear development, complete chiasma suppression resulting in achiasmate cells is attained prior to a quantitative reduction of chiasma frequency. Reduction of chiasma frequency and complete suppression are believed to be based on two different mechanisms.