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  • Author or Editor: R. P. S. Verma x
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Summary  

Sorption of inorganic mercury (Hg2+) and methyl mercury, on chemically synthesized polyaniline, in 0.1-10N HCl solutions has been studied. Hg2+ is strongly sorbed at low acidities and the extent of sorption decreases with increase in acidity. The sorption of methyl mercury is very low in the HCl concentration range studied. Sorption of Hg2+ on polyaniline in 0.1-10N LiCl and H2SO4 solutions has also been studied. The analysis of the data indicates that the sorption of Hg2+ depends on the degree of protonation of polyaniline and the nature of mercury(II) chloride complexes in solution. X-ray photoelectron spectroscopy analysis (XPS) of polyaniline sorbed with mercury show that mercury is bound as Hg2+. Sorbed mercury is quantitatively eluted from polyaniline with 0.5N HNO3. Polyaniline can be used for separation and pre-concentration of inorganic mercury from aqueous samples.

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Abstract  

Monazite (chief source of thorium) which is available in plenty in the beach sands of Kerala, India, contains uranium in the range of 0.25% to 0.35%. An attempt has been made to estimate 231Pa in monazite and the corresponding process stream samples of the thorium production cycle. This paper reports the 231Pa activity in these samples, after coprecipitation of 231Pa on MnO2 carrier and estimation by -ray spectrometry. The estimation shows about 1000 Bq/kg of 231Pa in monazite. This is the first reported estimate of 231Pa in monazite.

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A new molybdenum(VI) complex Cs2(NH4)2[Mo3O8(C2O4)3] (CAMO) has been prepared and characterized by chemical analysis and IR spectral studies. Thermal decomposition studies have been made using TG, DTA and DTG techniques. The compound is anhydrous and stable up to 160°C. Thereafter it decomposes in three stages. The first and the second stages occur in the temperature ranges 160–220°C and 220–280°C to give the intermediate compounds having the tentative compositions Cs4(NH4)2[Mo6O16(C2O4)3(CO3)2] and Cs4[Mo6O16(C2O4)2(CO3)2] respectively, the later then decomposing to give the end product Cs2Mo3O10 at 370°C. The end product was characterized by chemical analysis, IR spectral and X-ray studies.

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Pyrenophora teres f. teres (Ptt), causing net blotch in barley, is an important and frequently isolated leaf pathogen across the globe. The virulence spectrum of Ptt from North Africa including Morocco is poorly understood. Sixteen barley genotypes were challenged, at seedling stage, with 15 Ptt isolates that were collected from different agroecological zones of Morocco. The experiment was conducted in a factorial arrangement of treatments in a randomized complete block design with three replicates. The ANOVA revealed highly significant (P < 0.001) effects of genotype (G), isolate (I) and G×I interaction explaining 23.2, 62.5, and 13.9% of the variation, respectively. Therefore, the current study revealed highly diverse virulence pattern of Moroccan isolates. Furthermore, the results indicated that minor virulence of Ptt isolates dominated over virulence interaction. In addition, Taffa (6-rowed) and Aglou (2 rowed), had the highest level of resistance to Ptt, while Coast and Rabat071 were the most susceptible genotypes. Pt2, Pt7, Pt8 and Pt4 were being the most virulent isolates, while Pt10 and Pt11 were the least virulent isolates. The emergence of the new Ptt pathotypes, which were highly virulent to durable resistance in Rabat071 posed a risk of breaking down the currently deployed resistance to net blotch in Morocco. A careful evaluation and selection of Ptt isolates based on minor virulence pattern to barley genotypes is essential for successful barley breeding program for resistance to net blotch in Morocco.

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European Journal of Microbiology and Immunology
Authors: P. Vidyasagar, V. Nimmagadda Sridevi PhD, S. Rajan, A. Praveen, A. Srikanth, G. Abhinay, V. Siva Kumar, R. R. Verma and L. Rajendra

Abstract

Human papillomavirus (HPV) is the well-known second most cause of cervical cancer in women worldwide. According to the WHO survey, 70% of the total cervical cancers are associated with types HPV 16 and 18. Presently used prophylactic vaccine for HPV contains mainly capsid protein of L1 virus like particles (VLPs). Correct folding of VLPs and display of neutralizing epitopes are the major constraint for VLP-based vaccines. Further, monoclonal antibodies (mAbs) play a vital role in developing therapeutics and diagnostics. mAbs are also useful for the demonstration of VLP conformation, virus typing and product process assessment as well. In the present study, we have explored the usefulness of mAbs generated against sf-9 expressed HPV 16 VLPs demonstrated as type-specific and conformational dependent against HPV 16 VLPs by ELISA. High affinity and high pseudovirion neutralization titer of mAbs indicated their potential for the development of prophylactic vaccines for HPV. Also, the type-specific and conformational reactivity of the mAbs to HPV 16 VLPs in sf-9 cells by immunofluorescence assay proved their diagnostic potential.

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Cereal Research Communications
Authors: S. L. Krishnamurthy, S. K. Sharma, D. K. Sharma, P. C. Sharma, Y. P. Singh, V. K. Mishra, D. Burman, B. Maji, B. K. Bandyopadhyay, S. Mandal, S. K. Sarangi, R. K. Gautam, P. K. Singh, K. K. Manohara, B. C. Marandi, D. P. Singh, G. Padmavathi, P. B. Vanve, K. D. Patil, S. Thirumeni, O. P. Verma, A. H. Khan, S. Tiwari, M. Shakila, A. M. Ismail, G. B. Gregorio and R. K. Singh

Genotype × environment (G × E) interaction effects are of special interest for identifying the most suitable genotypes with respect to target environments, representative locations and other specific stresses. Twenty-two advanced breeding lines contributed by the national partners of the Salinity Tolerance Breeding Network (STBN) along with four checks were evaluated across 12 different salt affected sites comprising five coastal saline and seven alkaline environments in India. The study was conducted to assess the G × E interaction and stability of advanced breeding lines for yield and yield components using additive main effects and multiplicative interaction (AMMI) model. In the AMMI1 biplot, there were two mega-environments (ME) includes ME-A as CARI, KARAIKAL, TRICHY and NDUAT with winning genotype CSR 2K 262; and ME-B as KARSO, LUCKN, KARSA, GOA, CRRI, DRR, BIHAR and PANVE with winning genotypes CSR 36. Genotypes CSR 2K 262, CSR 27, NDRK 11-4, NDRK 11-3, NDRK 11-2, CSR 2K 255 and PNL 1-1-1-6-7-1 were identified as specifically adapted to favorable locations. The stability and adaptability of AMMI indicated that the best yielding genotypes were CSR 2K 262 for both coastal saline and alkaline environments and CSR 36 for alkaline environment. CARI and PANVEL were found as the most discernible environments for genotypic performance because of the greatest GE interaction. The genotype CSR 36 is specifically adapted to coastal saline environments GOA, KARSO, DRR, CRRI and BIHAR and while genotype CSR 2K 262 adapted to alkaline environments LUCKN, NDUAT, TRICH and KARAI. Use of most adapted lines could be used directly as varieties. Using them as donors for wide or specific adaptability with selection in the target environment offers the best opportunity for widening the genetic base of coastal salinity and alkalinity stress tolerance and development of adapted genotypes. Highly stable genotypes can improve the rice productivity in salt-affected areas and ensure livelihood of the resource poor farming communities.

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