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The present paper reports that significant genetic variability was evident in Fe, Zn, β-carotene, and phytic acid (phytate, PA) contents in a set of 39 diverse maize genotypes collected from maize breeding programme of hill agriculture, India. The Fe, Zn, β-carotene, and PA concentrations were found to be in the range 19.31–50.64 mg kg−1, 12.60–37.18 mg kg−1, 0.17–8.27 µg g−1, and 6.59–7.13 g kg−1, respectively. The genotypes V335, V420, V393, V416, V414, V372, and V351 were identified to have higher concentration of β-carotene, Fe, and Zn but lower amount of PA. Possible availability of the minerals Fe and Zn was determined using molar ratio between PA as inhibitor and β-carotene as promoter for their absorption. The micronutrient molar ratio showed that Fe and Zn traits could be dependent of each other. Low R2 value revealed relation between β-carotene and kernel colour. The selected genotypes could be considered as potential sources of favourable genes for further breeding programs to develop micronutrient enriched maize cultivars.

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Septoria tritici blotch (STB) caused by Mycosphaerella graminicola, is one of the most destructive foliar diseases of wheat (Triticum aestivum L.) especially in temperate and humid regions across the world. The susceptibility of recently released varieties, evolution of resistance to fungicides and increasing incidence of STB disease emphasizes the need to understand the genetics of resistance to this disease and to incorporate host resistance into adapted cultivars. This study aimed to decipher the genetics and map the resistance to STB using a recombinant inbred line (RIL) mapping population derived from ‘Steele-ND’ (susceptible parent) and ‘ND 735’ (resistant parent). The RILs were evaluated in three greenhouse experiments, using a North Dakota (ND) isolate of STB pathogen. The mean disease severity of parental genotypes, ‘ND 735’ (11.96%) and ‘Steele-ND’ (66.67%) showed significant differences (p < 0.05). The population segregated for STB and the frequency distribution of RILs indicated quantitative inheritance for resistance. The mean disease severity in RILs ranged from 0 to 71.55% with a mean of 21.98%. The genome map of this population was developed using diversity array technology (DArT) and simple sequence repeat (SSR) markers. The framework linkage map of this population was developed using 469 molecular markers. This map spanned a total distance of 1,789.3 cM and consisted of 17 linkage groups. QTL mapping using phenotypic data and the framework linkage maps detected three QTL through composite interval mapping. One QTL was consistently detected in all experiments on the long arm of chromosome 5B, and explained up to 10.2% phenotypic variation. The other two QTLs, detected in single environments, were mapped to 1D and 7A and explain 13% and 5.5% of the phenotypic variation, respectively. The map position of the consistent QTL on 5BL coincides with the map position of durable resistance gene Stb1 suggesting the importance of this region of ‘ND 735’ as a source of durable STB resistance for the wheat germplasm.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: S. Ravi, S. Ravi, A. K. Deepa, A. K. Deepa, S. Susheela, S. Susheela, P. V. Achuthan, P. V. Achuthan, S. Anil Kumar and U. Jambunathan

Summary  

A method has been developed for the estimation of 90Sr in reprocessed uranium oxide samples obtained from the Purex processing of natural uranium spent fuel discharged from the research reactor. The method employs a combination of precipitation and solvent extraction procedure to eliminate other beta-impurities prior to resorting to the estimation of 90Sr by beta-counting. 106Ru was eliminated by volatalizing with perchloric acid, uranium was removed by carrier precipitation with strontium as sulphate. The sulphate precipitate was converted to carbonate and dissolved in nitric acid. 234Th and 234Pa were eliminated by synergistic solvent extraction using tri-n-butyl phosphate and thenoyl trifluoroacetone extractant mixture in xylene. An iron scavenging step was included to remove any residual impurities. Finally, strontium is precipitated as SrC2O4 . H2O. The separated 90Sr activity was followed to check the equilibrium growth of 90Y.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: S. Ravi, A. Deepa, B. Surekha, S. Susheela, P. Achuthan, S. Anil Kumar, K. Vijayan, U. Jambunathan, S. Munshi and P. Dey

Abstract  

90Sr estimation in reprocessed uranium was carried out by a series of solvent extraction and carrier precipitation techniques using strontium and lanthanum carriers. Fuming with HClO4 was used to remove 106Ru as RuO4. Three step solvent extraction with 50% tri-n-butyl phosphate in xylene in presence of small amounts of dibutyl phosphate and thenoyl trifluoro acetone was carried out to eliminate uranium, plutonium, thorium and protactinium impurities. Lanthanum oxalate precipitation in acid medium was employed to scavenge the remaining multivalent ions. Strontium was precipitated as strontium oxalate in alkaline pH and 137 Cs was removed by washing the precipitate with water. A strontium recovery well above 70% was obtained. Final estimation was carried out by radiometry using end window GM counter after drying the precipitate under an infra red lamp. The same procedure was extended to the estimation of 90Sr in a diluted sample of the actual spent fuel solution. An additional lanthanum oxalate precipitation step was required to remove the entire 144Ce impurity from this sample. This modified procedure was employed in the determination of 90Sr in a number of reprocessed uranium samples and the over all precision of the method was found to be well within ±10%. An additional barium chromate precipitation step was necessary for the analysis of reprocessed uranium samples from high bumup fuels to eliminate trace amounts of short lived 224Ra produced during the decay of 232U and its daughters as they interfere in the estimation of 90Sr.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: P. Govindan, S. Sukumar, K. Vijayan, G. Santhosh Kumar, S. Ganesh, Pradeep Sharma, K. Dhamodharan, R. Subba Rao, M. Venkataraman and R. Natarajan

Abstract  

A novel method has been developed for recovery of plutonium and uranium from carbonate wash solutions generated during solvent wash process involved in the reprocessing of high burn up FBTR fuel. The proposed method involves a selective coprecipitation of Pu and U by adding ammonium hydroxide to the pre acidified carbonate wash solution. Substantial removal of DBP by successive steps of coprecipitation, completely eliminates the possibility of undesired solid formation which is mainly due to the presence of high content of DBP. By adopting this method, an excellent decontamination factor for DBP has been achieved without any crud/solid formation. Phosphate content in the final oxide product meets the product specifications. Flowsheet condition necessary for the recovery process for plutonium from the aqueous carbonate solution is formulated and adopted in the CORAL facility.

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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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European Journal of Microbiology and Immunology
Authors: Gangadhararao Appana, Dipankar Das, Maroudam Veerasami, Ramachandran Lakshmikanthan Senthilkumar, Munishkumar Durishetty, B. Ramalakshmi, Vijay Bahekar, Falguni Mukherjee, Dev Chandran, P. Uday Kumar, B. Sesikeran and Villuppanoor Alwar Srinivasan Ph.D.

Abstract

A male cattle calf was detected as subclinically and naturally infected with Mycobacterium avium subspecies paratuberculosis (MAP) by a series of antemortem and postmortem tests. The MAP infection was identified by strong antibody and cell-mediated immune (CMI) response by a commercial ELISA kit and an intradermal Johnin test, respectively, in the initial antemortem examination. The antemortem status of the calf was further confirmed by MAP-specific interferon gamma (IFN-γ) response. For detection of IFN-γ response, MAP-specific IFN-γ release assays (IGRAs): (a) immuno capture ELISA (IC-ELISA) and (b) ELISPOT was employed. In addition, the presence of intracellular cytokine IFN-γ was detected by flow cytometry. For all cytokine assays, MAP-specific recombinant antigens HSP65 and 35 kDa were employed to overcome the poor sensitivity and specificity resulting from the use of Johnin, the crude protein purified derivative of MAP. Postmortem examination of the MAP-infected/suspected cattle calf did not reveal any pathognomonic gross lesions in the gastro-intestinal tract. Histopathological examination of multiple organs showed the presence of epithelioid cells/macrophages and edematous lesions in the mesenteric lymph nodes suggestive of MAP; however, no granulomas were observed in the intestinal tract. The necropsy samples of rectum and mesenteric lymph nodes were positive for isolation of MAP by culture in the BACTEC™ MGIT™ 960 system, and acid fast bacilli were demonstrated by fluorescence microscopy confirming the infection. Due to differential and complex expression patterns of MAP antigens reported in literature, a combination of assays such as those based on IGRAs and antibody detection is essential. Therefore, the current experimental evidence confirms the efficacy of the approach adopted. However, further studies will be needed to understand the optimal combination MAP-specific antigens for use in IGRAs or antibody assays that can be used for detecting MAP infection in every stage of the disease.

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Acta Chromatographica
Authors: Azazahemad A. Kureshi, Chirag Dholakiya, Tabaruk Hussain, Amit Mirgal, Siddhesh P. Salvi, Pritam C. Barua, Madhumita Talukdar, C. Beena, Ashish Kar, T. John Zachariah, Premlata Kumari, Tushar Dhanani, Raghuraj Singh and Satyanshu Kumar

Xanthones are well recognized as chemotaxonomic markers for the plants belonging to the genus Garcinia. Xanthones have many interesting pharmacological properties. Efficient extraction and rapid liquid chromatography methods are essentially required for qualitative and quantitative determination of xanthones in their natural sources. In the present investigation, fruit rinds extracts of 8 Garcinia species from India, were prepared with solvents of varying polarity. Identification and quantification of 3 xanthones, namely, α-mangostin, β-mangostin, and γ-mangostin in these extracts were carried out using a rapid and validated ultra-high-performance liquid chromatography–photodiode array detection (UHPLC–PDA) method at 254 nm. γ-Mangostin (3.97 ± 0.05 min) was first eluted, and it was followed by α-mangostin (4.68 ± 0.03 min) and β-mangostin (5.60 ± 0.04 min). The calibration curve for α-mangostin, β-mangostin, and γ- mangostin was linear in the concentration range 0.781–100 μg/mL. α-Mangostin was quantified in all 4 extracts of Garcinia mangostana. Its content (%) in hexane, chloroform, ethyl acetate, and methanol extracts of G. mangostana was 10.36 ± 0.10, 4.88 ± 0.01, 3.98 ± 0.004, and 0.044 ± 0.002, respectively. However, the content of α-mangostin was below the limit of detection or limit of quantification in the extracts of other Garcinia species. Similarly, β-mangostin was quantified only in hexane (1.17 ± 0.01%), chloroform (0.39 ± 0.07%), and ethyl acetate (0.28 ± 0.03%) extracts of G. mangostana. γ-Mangostin was quantified in all 4 extracts of G. mangostana. Its content (%) in hexane, chloroform, ethyl acetate, and methanol extracts of G. mangostana was 0.84 ± 0.01, 1.04 ± 0.01, 0.63 ± 0.04, and 0.15 ± 0.01, respectively. γ-Mangostin was also quantified in hexane (0.09 ± 0.01), chloroform (0.05 ± 0.01), and ethyl acetate (0.03 ± 0.01) extracts of G. cowa, ethyl acetate extract of G. cambogia (0.02 ± 0.01), G. indica (0.03 ± 0.01), and G. loniceroides (0.07 ± 0.01). Similarly, γ-mangostin was quantified in 3 extracts of G. morella, namely, hexane (0.03 ± 0.01), chloroform (0.04 ± 0.01), and methanol (0.03 ± 0.01). In the case of G. xanthochymus, γ-mangostin was quantified in chloroform (0.03 ± 0.001) extract only. α-Mangostin and β-mangostin were not detected in any of 4 extracts of G. pedunculata.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: M. Krivopustov, A. Pavliouk, A. Kovalenko, I. Mariin, A. Elishev, J. Adam, A. Kovalik, Yu. Batusov, V. Kalinnikov, V. Brudanin, P. Chaloun, V. Tsoupko-Sitnikov, A. Solnyshkin, V. Stegailov, Sh. Gerbish, O. Svoboda, Z. Dubnicka, M. Kala, M. Kloc, A. Krasa, A. Kugler, M. Majerle, V. Wagner, R. Brandt, W. Westmeier, H. Robotham, K. Siemon, M. Bielewicz, S. Kilim, M. Szuta, E. Strugalska-Gola, A. Wojeciechowski, S. Hashemi-Nezhad, M. Manolopoulou, M. Fragopolou, S. Stoulos, M. Zamani-Valasiadou, S. Jokic, K. Katovsky, O. Schastny, I. Zhuk, A. Potapenko, A. Safronova, Zh. Lukashevich, V. Voronko, V. Sotnikov, V. Sidorenko, W. Ensinger, H. Severin, S. Batsev, L. Kostov, Kh. Protokhristov, Ch. Stoyanov, O. Yordanov, P. Zhivkov, A. Kumar, M. Sharma, A. Khilmanovich, B. Marcinkevich, S. Korneev, Ts. Damdinsuren, Ts. Togoo and H. Kumawat

Abstract  

An extended U/Pb-assembly was irradiated with an extracted beam of 2.52 GeV deuterons from the Nuclotron accelerator of the Laboratory of High Energies within the JINR in Dubna, Russia. The lay-out of this experiment and first results are reported. The Pb-target (diameter 8.4 cm, length 45.6 cm) is surrounded by a natU-blanket (206.4 kg) and used for transmutation studies of hermetically sealed radioactive samples of 129I, 237Np, 238Pu and 239Pu. Estimates of transmutation rates were obtained as result of measurements of gamma-activities of the samples. Information about the spatial and energy distribution of neutrons in the volume of the lead target and the uranium blanket was obtained with sets of activation threshold detectors (Al, Y and Au) and solid state nuclear track detectors (SSNTD). An electronic 3He neutron detector was tested on-line. A comparison of experimental data with theoretical model calculations using the MCNPX program was performed yielding satisfactory results.

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