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Abstract  

The solubility of NdPO4(c) was studied at 23±2 °C from both the over and undersaturation directions, with pH ranging from 0 to 9, P concentrations ranging from 0.0003 to 1.00M, and equilibration periods ranging from 6 to 57 days. Equilibrium was reached in <6 days. From the H+, Nd, and P concentrations in equilibrated solutions, the logarithm of the thermodynamic equilibrium constant for the reaction (NdPO4(c) Nd3++PO4 3-) was calculated to be -24.65±0.23 and the value of the Pitzer ion-interaction parameter (2)for Nd3+-H2PO4 - was determined to be -92.9. Predictions based on these thermodynamic quantities were in excellent agreement with the experimental data.

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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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A Global Positioning System (GPS) permanent station has been established as a reference point at the Department of Civil Engineering of Indian Institute of Technology Bombay (IITB), by the IITB GPS group, and is continuously operating since January 2002. The station is being operated under a research project funded by the Department of Science and Technology (DST), Government of India, under the “National GPS Programme for Earthquake Studies”. A brief description of the station set up, the strategy used in determining its precise position, and some sample results are presented in this paper.

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Inheritance of male sterility and fertility restoration of the A 1 system of cytoplasmic-nuclear male sterility in pearl millet was investigated using 12 crosses among three diverse male sterile lines (A-lines) and four diverse restorers (R-lines). Individual plants from R- lines were used to make crosses on A-lines. The segregation pattern of male sterile (S) and male fertile (F) plants observed in F 2 and BC 1 in two seasons at ICRISAT, Patancheru was suggestive more likely of a single-gene control of male sterility and fertility restoration. However, a 3-gene model of male sterility/fertility restoration where dominant alleles at any two of the three duplicate complimentary loci will lead to male fertility could not be ruled out, nor could be ruled out a 2-gene control with duplicate interaction. There was indication of variability even within a highly inbred R-line for fertility restoration gene(s). Depending on the genetic constitution of the R-lines at these loci, even the 3-gene model can lead to single-gene segregation ratios as observed in most of the F 2s and backcrosses, and 2-gene ratios as observed in a few F 2s and backcrosses. The deviations from these expected ratios in some of the crosses influenced by modifiers and environmental conditions generally resulted from the excess of fertile plants in the rainy season or excess of sterile plants in the dry season, the more so in crosses involving an A-line which has been reported to be relatively more unstable for male sterility.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
M. Alrakabi
,
G. Singh
,
A. Bhalla
,
S. Kumar
,
S. Kumar
,
A. Srivastava
,
B. Rai
,
N. Singh
,
J. Shahi
, and
D. Mehta

Abstract  

The elemental concentration of uranium in the samples collected from the ground water and the canal water in the Bathinda district of Punjab state, India, have been investigated using X-ray fluorescence technique. The residues obtained after drying the water samples were analysed using the energy dispersive X-ray fluorescence spectrometer consisting of Mo-anode X-ray tube equipped with selective absorbers as an excitation source and an Si(Li) detector. The uranium concentration values in significant fraction of the shallow ground water samples from the hand pumps is found to be above the permissible level of 15 ppb recommended by World Health Organisation for the drinking water, and its values in the canal water samples are below 5 ppb. To investigate the flyash from the coal-fired thermal power plants as a possible source of ground water contamination, the water samples collected from the surroundings of the power plants and the flyash samples were also analyzed. The results rule out flyash as a source of uranium contamination. Agrochemical processes occurring in the calcareous soils in the region are the favoured potential source of uranium contamination of the ground water.

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