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Abstract

The concept of a Lie recurrence was introduced by the first author [6]. It is an infinitesimal transformation with respect to which the Lie derivative of a curvature tensor is proportional to itself. Apart from other results related to a Lie recurrence, it was established that the Weyl projective curvature tensor is Lie recurrent with respect to a Lie recurrence but its converse is not necessarily true. However, an infinitesimal transformation with respect to which the Weyl projective curvature tensor and the Ricci tensor are Lie recurrent, is necessarily a Lie recurrence. Singh [12] studied an infinitesimal transformation with respect to which the Lie derivative of the curvature tensor is proportional to itself and called such transformation as curvature inheritance. Obviously, a curvature inheritance is nothing but a Lie recurrence. Singh [13] also considered a curvature inheritance which is a projective motion and called it a projective curvature inheritance. Gatoto and Singh [1,2] studied -curvature inheritance and projective -curvature inheritance. Pandey and Pandey [9] studied projective Lie recurrence. Mishra and Yadav [3] studied projective curvature inheritance in an NP-F n. In the present paper we have established that an infinitesimal transformation in a Finsler space is Lie recurrence if and only if the normal projective curvature tensor is Lie recurrent. A part from this result we have generalized almost all theorems of Mishra and Yadav [3].

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Abstract  

A simple and rapid, laser fluorimetric method for the determination of uranium concentration in raffinate stream of Purex process during reprocessing of spent nuclear fuel has been developed. It works on the principle of detection of fluorescence of uranyl complex formed by using fluorescence enhancing reagent like sodium pyrophosphate. The uranium concentration was determined in the range of 0–40 ppb and detection limit of 0.2 ppb. The optimum time discrimination is obtained when the uranyl ion is complexed with sodium pyrophosphate. Need of preconcentration step or separation of uranium from interfering elements is not an essential step.

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Yellow mosaic and leaf curling symptoms were observed on Ageratum conyzoides plants in a survey made during 2007–09 at Gorakhpur and nearby locations of North-Eastern Uttar Pradesh, India. The incident of disease was significantly high with severe symptoms. Due to presence of whiteflies in the field, begomovirus infection was suspected. Therefore, polymerase chain reaction (PCR) was performed with begomovirus specific primers (TLCV-CP). Total genomic DNA was isolated from infected as well as healthy leaf samples. In gel electrophoresis an ∼800 bp amplicon was obtained in diseased leaf samples as expected, while no amplicon was found in healthy plants.Amplicons obtained were directly sequenced and submitted to the GenBank with the accession number GQ412352 and a phylogeny tree was constructed with the available sequences in the Genbank. Based on the highest nucleotide similarity (98%), amino acid similarity and close relationship with isolates of Ageratum enation virus, the present isolate was considered as an isolate of Ageratum enation virus.

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Zinc is essentially required for crop growth and its insufficient supply to the plants may severely limit the yield traits of a crop. A field experiment was performed during rabi season of 2009–10 and 2010–11 to evaluate the performance of different wheat genotypes under different levels of zinc namely 0 kg ZnSO4 ha−1, 20 kg ZnSO4 ha−1 and 20 kg ZnSO4 ha−1 along with foliar spray of 0.5% solution of ZnSO4. Genotypes responded positively in terms of tiller number, grain and biological yield, spikelet length, spikelet number, grain number and thousandgrain weight. The best response was observed with the application of 20 kg ZnSO4 ha−1 along with foliar spray of 0.5% solution of ZnSO4. Zinc application brought about a maximum increase of 58.6% in tiller number, 63.7% in thousand-grain weight, 40.5% in biological yield, 66.1% in grain yield irrespective of genotypes and the year of study. Wheat genotypes exhibited a variation in their performance which has been exploited in this study. Genotypes UP-262, PBW-175, PBW-343 were found to be superior for one or the other yield contributing factors.

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Cereal Research Communications
Authors: N. Jain, G.P. Singh, R. Yadav, R. Pandey, P. Ramya, M.B. Shine, V.C. Pandey, N. Rai, J. Jha, and K.V. Prabhu

Under limiting water resources, root system response of genotypes to soil-water conditions with enhanced shoot biomass holds the key for development of improved genotypes. Based on the hypothesis of root biomass contribution to higher yields under limiting conditions which might be attributed to the root system plasticity of genotypes, a set of thirty-four genotypes were evaluated under three moisture regimes in a pot experiment for root system traits. Total root dry matter had a positive association with total shoot dry matter (0.35). The identified genotypes showed greater yields and higher stress tolerance index (STI) in an independent field experiment. Root dry matter positively correlated with stress tolerance index on grain yields in both the years. The total variation was partitioned into principal components and GGE biplots were studied to identify the best performing genotypes under the three environments for root dry biomass and related traits. HD2932 appeared to be the winner genotype under different regimes. These results might be helpful in identifying donors for moisture stress tolerance that can be utilized in wheat breeding programmes for accelerated development of varieties with improved root systems.

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Abstract  

A spectrophotometric method is developed for the determination of dissolved tri-n butyl phosphate (TBP) in aqueous streams of Purex process used in nuclear fuel reprocessing. The method is based on the formation of phosphomolybdate with added ammonium molybdate followed by reduction with hydrazine sulphate in acid medium. Orthophosphate and molybdate ions combine in acidic solution to give molybdophosphoric (phosphomolybdic) acid, which upon selective reduction (with hydrazinium sulphate) produces a blue colour, due to molybdenum blue. The intensity of blue colour is proportional to the amount of phosphate. If the acidity at the time of reduction is 0.5 M in sulphuric acid and hydrazinium sulphate is the reductant, the resulting blue complex exhibits maximum absorption at 810–840 nm. The system obeys Lambert–Beer’s law at 830 nm in the concentration range of 0.1–1.0 μg/ml of phosphate. Molar Absorptivity was determined to be 3.1 × 10L mol−1 cm−1 at 830 nm. The results obtained are reproducible with standard deviation of 1 % and relative error less than 2 % and are in good agreement with those obtained by ion chromatographic technique.

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