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  • Author or Editor: R. Kumar x
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Aim of this study is to analyze the effect of chronic administration of beta agonist isoproterenol hydrochloride (60 mg kg −1 day −1 ; 30 days) on soleus (a slow type) and extensor digitorum longus (EDL, a fast type) muscles in young mice. Isoproterenol resulted in significant increase in muscle weight to whole body weight ratio with no increase in hypertrophy index in soleus muscle. A significant increase in noncontractile protein collagen is also observed in both muscles but more prominent in soleus muscle. Collagen proliferation is also analyzed on sodium dodecyle sulphate polyacrylamide gel electrophoresis (SDS-PAGE) of pepsin soluble and Cyanogen Bromide (CNBr) treated pepsin insoluble collagen. Isoproterenol remolded the myofibrillar proteins in both muscles but significant increase in myofibrillar ATPase activity occurred only in soleus muscle. It is concluded that growth stimulatory effect of isoproterenol hydrochloride is more prominent in soleus than EDL muscle. Isoproterenol augmented the proliferation of non-contractile protein collagen in soleus and EDL muscles. The transformation in myofibrillar proteins caused by isoproterenol might lead to an enhancement of contractile performance.

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Summary

Two new structural variants of Marfey's reagent (1-fluoro-2,4-dinitrophenyl-5-l-alaninamide, FDNP-l-Ala-NH2) were synthesized by nucleophilic substitution of one fluorine atom in 1,5-difluoro-2,4-dinitrobenzene (DFDNB) by l-methioninamide or d-phenylglycinamide. The new variants FDNP-l-Met-NH2 and FDNP-d-Phg-NH2 were characterized and used for derivatization of twenty-six α-amino acids. The resulting diastereomeric derivatives were separated on a reversed-phase C18 HPLC column using a linear gradient of acetonitrile and aqueous trifluoroacetic acid (TFA) and the results were compared with those obtained by use of Marfey's reagent. To determine and establish the efficiency of both the new variants, separation results were compared for diastereomers of five representative amino acids (Ala, Phe, Ser, Asp, and Asn) prepared with MR, FDNP-l-Phe-NH2, FDNP-l-Val-NH2, FDNP-l-Leu-NH2, and FDNP-l-Pro-NH2, experiments being performed under identical conditions. Both the new chiral reagents enabled better separation of the diastereomers than Marfey's reagent for most of the amino acids. The reagent FDNP-d-Phg-NH2 enabled excellent separation for serine and asparagine whereas other reagents failed or provided poor results.

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Wheat is one of the staple food crops in major areas of the world providing the required carbohydrate and proteins in our diet. A decrease in the total yield of wheat has been observed worldwide due to elevation in environmental temperature. Heat stress causes pollen sterility, drying of stigmatic fluid, pseudo-seed setting, empty pockets in endosperm and shrivelled seeds in wheat. Every plant system has defence mechanisms to cope up with the different environmental challenges. The defence mechanisms of wheat consist of heat responsive miRNAs, signalling molecules, transcription factors and stress associated proteins like heat shock proteins (HSPs), antioxidant enzymes etc. Wheat is sensitive to heat stress especially in stages like pollination to milky dough kernel stages is critical for growth and development. Heat stress causes an oxidative burst inside cell system followed by increase in the expression of various proteins like protein kinases, HSPs and antioxidant enzymes. These stress proteins modulate the defence mechanisms of wheat by protecting the denaturation and aggregation of nascent proteins involved in various metabolic reactions. Genetic variation has been observed with respect to expression and accumulation of these stress proteins. Exogenous treatment of various hormones, signalling molecules and chemicals has been reported to enhance the thermotolerance level of wheat under heat stress. Tools of genetic engineering have been also used to develop wheat transgenic lines with over-expression of stress proteins under heat stress condition. There is an arduous task in front of breeders and molecular biologists to develop a climate smart wheat crop with sustainable yield under the threat of global climate change.

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Abstract  

The phase analysis of the rusts generated beneath the primer containing micaceous iron oxide (MIO) and micaceous iron oxide in combination with red lead (RL), zinc phosphate (ZP), basic lead silicochromate (BLSC) and zinc chromate (ZC) has been carried out by Mössbauer spectroscopy at room temperature. The rust beneath the coating obtained after immersion of the painted panel for six months in 3% NaCl, consists mainly of nonstoichiometric magnetite together with small fractions of γ-, α-FeOOH except in the case of panel painted with RL containing MIO showed only a central doublet indicating the formation of γ-FeOOH and SPM α-FeOOH. Non-stoichiometry of magnetite as calculated from the ratio of B/A sites of the peaks of magnetite in the spectrum has been found depending on the nature of anticorrosive pigment present in the primer coating. The order of non-stoichiometry has been found to be in order of ZC>BLSC>ZP>MIO.

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Summary Tris(dicarboxylate) complexes of iron(III) with oxalate, maleate, malonate and phthalate viz. K3[Fe(C2O4)3]×3H2O (1), K3[Fe(OOCCH2COO)3]×3H2O (2), K3[Fe(OOCCH=CHCOO)3]×3H2O (3), K3[Fe(OOC-1,2-(C6H4)-COO)3]×3H2O (4) have been synthesized and characterized using a combination of physicochemical techniques. The thermal decomposition behaviour of these complexes have been investigated under dynamic air atmosphere upto 800 K. All these complexes undergo a three-step dehydration/decomposition process for which the kinetic parameters have been calculated using Freeman-Carrol model as well as using different mechanistic models of the solid-state reactions. The trisoxalato and trismalonato ferrate(III) complexes undergo rapid dehydration at lower temperature below 470 K. At moderately higher temperatures (i.e. >600 and 500 K, respectively) they formed bis chelate iron(III) complexes. The trismalonato and trismaleato complexes dehydrate with almost equal ease but the latter is much less stable to decomposition and yields FeCO3 below 760 K. The cis-dicarboxylate complexes particularly with maleate(2-) and phthalate(2-) ligands are highly prone to the loss of cyclic anhydrides at moderately raised temperatures. The thermal decomposition of the tris(dicarboxylato)iron(II) to iron oxide was not observed in the investigated temperature range up to 800 K. The dehydration processes generally followed the first or second order mechanism while the third decomposition steps followed either three-dimensional diffusion or contracting volume mechanism.

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A field experiment conducted on the sandy loam soil in New Delhi during the winter season of 2003–2004 indicated that the application of three irrigations at the branching, flowering and seed formation stages gave the maximum values of growth and yield attributes (plant height and branches plant −1 , umbels plant −1 , umbellets umbel −1 and seeds umbel −1 ) with the highest seed and stover yields, but was at par with omitting one irrigation at the seed formation stage. The data on the growth and yield indicated that, compared to the other stages, omitting irrigation at the flowering strage resulted in the greatest reduction. The growth and yield attributes and the seed and stover yield of coriander significantly responded to fertilization up to 80 kg N ha −1 . The crop evapotranspiration was the highest with the application of three irrigations, but the water use efficiency remained the highest when irrigation was omitted at the seed formation stage. Nitrogen fertilization up to 120 kg and 80 kg N ha −1 increased the water use and water use efficiency, respectively.

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The regeneration potential of pearl millet, a crop which is of vital importance for farmers in semi-arid tropical regions, was evaluated in a 12 × 12 line × tester cross involving six male sterile (A) lines from five systems of cytoplasmic-genic male sterility, namely two male sterile lines from system A1 (MS81A1, MS8A1), and one each from A2 (Pb313A2), A3 (Pb402A3), A4 (MS81A4) and A5 (MS81A5), the six corresponding maintainer (B) lines 81B1, 8B1, Pb313B2, Pb402B3, 81B4and 81B5, and twelve restorer (R) lines, namely H90/4-5, H77/833-2, G73-107, CSSC46-2, 77/245, 78/711, 77/273, ICR 161, ISK48, 77/28-2, 77/180 and Raj 42. The 24 parents and 144 crosses were grown separately in contiguous blocks in a randomized block design with two replications in three treatments each in 2000 and 2001 at the Research Farm, Bajra Section, Department of Plant Breeding, CCS HAU, Hisar. The plot size was 2.5 m × 0.45 m with 10 cm intra-row spacing. The genotypes (A lines, B lines, R lines, A × R crosses, B × R crosses), sowing dates, years, year × sowing date and genotype × treatment interactions (direct and reciprocal) exhibited significant differences. The comparison of mean performance of the early-sown non-ratooned crop vs. ratooned (cut, regenerated) vs. late-sown unratooned crop treatments revealed that both the grain and dry fodder yields and the major yield-contributing characters exhibited little reduction in the ratoon crop, while the total tillers at maturity and the effective tillers increased in the ratoon crop in comparison to the direct-sown crop. Additional green fodder yields of 189.63 g and 144.02 g per plant, harvested 40 days after sowing (DAS) in the ratoon crops in 2000 and 2001, respectively, and similar grain and dry fodder yields emphasized the utility of cutting and regeneration in pearl millet. The ratooning ability of genotypes, assessed from the ratio of the performance of various characters in ratoon and early and late sown unratooned crops for yield and major yield components was high for a number of lines, testers and hybrids. Most of the hybrids involved one or two parents with good regeneration potential. Sufficient genetic variability was observed for regeneration and ratooning ability, which was found to be under genetic control, suggesting that regeneration potential could be incorporated in genotypes with high yield. A base population developed from promising parents and crosses can be improved by cyclic breeding.

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Abstract  

Corrosion products of mild steel exposed to four different cultures of sulfur reducing bacteria (SRB) grown in a synthetic medium have been studied by transmission Mössbauer spectroscopy (TMS). Cultures of SRB studied are two hydrogenase positive strains,Desulfovibrio desulfuricans (DD) andDesulfovibrio vulgaris (DV) and two hydrogenase negative strainsDesulfotomaculum orientis orientis (DO) andDesulfotomaculum nigrificans (DN). The corrosion products generated on the coupons as well as in the broth were studied. In all the cases, the corrosion products removed from coupons showed the presence of green rust 2 (GR2), ferrous sulfides, γ-FeOOH and superparamagnetic (SPM) α-FeOOH in different proportions. The corrosion products from the broth showed a symmetrical central doublet, which indicates the presence of γ-FeOOH and SPM α-FeOOH along with ferrous sulfides. The corrosion products from coupons suspended in sewage water also showed the presence of GR 2 and ferrous sulfides together with oxyhydroxides. FTIR spectrum supports the presence of these phases in corrosion products. The formation of GR 2 on coupons seems to be the first step for the SRB induced corrosion. The corrosion rate has been found in the order of DO>DN>DV>DD.

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Abstract  

Polyaniline sorbed with microgram quantity of mercury was prepared and its homogeneity and stability with respect to mercury was evaluated over a period of time. The volatilisation loss of mercury during and after neutron irradiation was studied. It was found that polyaniline was homogeneous and stable with respect to mercury. No loss of mercury from polyaniline was observed during and after neutron irradiation. Thus polyaniline sorbed with mercury can serve as a good standard for neutron activation analysis of mercury.

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A study was undertaken to determine the genetics of corn leaf aphid (CLA) resistance in barley under controlled conditions with artificial inoculation at adult plant stage. Inheritance of CLA resistance was investigated in five resistant barley genotypes (EB921, EB2507, Manjula, DL529 and K144) in crosses with susceptible parent Alfa93 in F1, F2, F3 and backcross (BCF1) generations. The aphid inoculation was done using the brush method as well as the detached leaf method. Individual plants were classified in resistant, moderately resistant, susceptible and highly susceptible categories base on number per shoot as well as multiplication of CLA on any of the fresh, young leaf. The plants scored as resistant or moderately resistant were observed twice more at 10 days interval to confirm their reaction. Resistance was governed by a single dominant gene in EB921, DL529 and K144, while it was monogenic recessive in Manjula and EB2507. These diverse sources may be used in breeding for CLA resistance in barley improvement programme.

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