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Abstract  

Double sulfates of thallium and lanthanides form an interesting series of compounds with first fractional crystallization leading to the formation of tetrahydrated double sulfates. The radiation induced defects including changes in the oxidation states were studied by carrying out EPR investigations of -irradiated Tl (I) Ln (III) (SO4)2.4H2O (Ln=Sm, Eu and Nd) compounds. The important finding of these investigations is the formation of a radiation-induced paramagnetic center Tl2+ simultaneously with that of Eu2+, revealing their intrinsic association. Similar formation of Tl2+ was not observed in other rare earth salts, implying that the stability of the half-filled electronic configuration of Eu2+ may be responsible for the stabilization of Tl2+. Their relaxation back to Eu3+ and Tl+ simultaneously at 255 K gives further confirmation of their association and suggests that the matrix intrinsically does not favor the stabilization of Eu2+ as reported in a number of other matrices. The hyperfine coupling constant for Tl2+ was calculated using the Breit-Rabi equation and was found to be 80 GHz.

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Abstract

Effect of microwave drying on milling, cooking, and microstructure characteristic of paddy rice in comparison to hot air drying was assessed in the present study. Results revealed that modified microwave drying significantly (P < 0.05) affected the milling quality of paddy. Raw paddy had head rice recovery of 49.63%, while after microwave drying, the head rice recovery increased by 6.73% in comparison to hot air drying. Microwave drying brought significant changes in the colour characteristic of rice as it had total colour change of 13.50 in comparison to 10.93 by hot air drying. Cooking time and water uptake ratio after microwave drying increased to 31.46 min and 3.16%, in comparison to 27.05 min and 2.65% for hot air dried samples, respectively. Scanning Electron Microscope images revealed that both hot air and microwave dried rice had a coarse surface and large starch particles, while starch structure was more damaged in hot air drying, however, agglomeration of protein-starch matrix was more uniform in microwave dried samples due to modification of the microwave applicator that prevented thermal decomposition. It was recommended that paddy may be dried using a modified microwave applicator with a shorter duration and a better quality.

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A field study conducted for two years (2002–04) at New Delhi showed that the seed yield (1.80 t ha −1 ) of rocket salad ( Eruca sativa Mill.) obtained by applying 5 t ha −1 pressmud compost based on distillery effluent + half the recommended dose of NPKS (recommended dose: 60 kg N, 13 kg P, 25 kg K and 20 kg S ha −1 ) was on par with the seed yield (1.69 t ha −1 ) recorded with the recommended dose of NPKS. However, the seed yield recorded with the former treatment significantly exceeded that obtained with 5 t ha −1 of a 1:1 mixture of fly ash and distillery effluent + half the recommended dose of NPKS (by 30.4%) or 5 t ha −1 of dry Jatropha curcas leaves + ½ NPKS (by 24.1%). On average, distillery effluent-based pressmud compost + ½ NPKS induced a perceptible increase in the soil-available NPK, recorded after the harvest of rocket salad, compared to the initial fertility status. The uptake of NPKS in the seed and stover of rocket salad was the highest after the application of pressmud compost, closely followed by the recommended dose of NPKS, and the lowest in the control. The residual effect of treatments given to rocket salad was significant on the fodder yield of succeeding sorghum [ Sorghum bicolor (L.) Moench]. The fodder yield recorded with pressmud compost + ½ NPKS was significantly higher than the other treatments. The application of pressmud compost alone was also significantly superior to the same rate of fly ash + effluent mixture or dry Jatropha leaves with respect to the seed yield of rocket salad, residual fertility after the harvest of rocket salad and the fodder yield of succeeding sorghum.

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Abstract

Methicillin-resistant coagulase-negative staphylococci (MR-CoNS) cause infectious diseases due to their potential to form biofilm and further colonization in hospital materials. This study evaluated the antibiotic susceptible phenotypes, biofilm-producing ability, and biofilm-associated genes (mecA, icaAD, bap, cna, and fnbA). Biofilm formation was detected through Congo red agar (CRA) method and MTP method. The presence of biofilm and associated genes in MR-CoNS were detected by PCR. A total of 310 (55.95%) isolates produced the biofilm. Among these isolates, Staphylococcus haemolyticus (34.83%), Staphylococcus epidermis (31.93%), Staphylococcus capitis (16.77%), Staphylococcus cohnii (10.96%), and Staphylococcus hominis (5.48%) were identified. The antimicrobial susceptibility pattern of CoNS isolates indicated resistance to cefoxitin (100%), erythromycin (94.8%), ciprofloxacin (66.7%), sulfamethoxazole/trimethoprim (66.7%), gentamicin (66.12%), and clindamycin (62.9%). Resistance rate to mupirocin was 48.5% in S. epidermidis and 38.9% in S. haemolyticus isolates. All isolates were sensitive to vancomycin and linezolid.

The prevalence rates of icaAD, bap, fnbA, and cna were 18.06%, 12.5%, 47.4%, and 27.4%, respectively. icaAD and bap genes were detected in 18.06% and 12.5% of MR-CoNS isolates. fnbA and cna genes were detected in 47.41% and 27.41% of MRCoNS isolates. icaAD positive strains exhibited a significant increase in the biofilm formation compared with those that lacked icaAD (0.86 (0.42, 1.39) versus 0.36 (0.14, 0.75), respectively; P < 0.001).

In conclusion, the majority of MR-CoNS isolates were biofilm producers, and S. capitis, which possessed icaAD genes, ranked as the great biofilm producer than other Staphylococcus. The study’s findings are important to form a strategy to control biofilm formation as an alternative strategy to counter the spread of MR-CoNS in healthcare settings.

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Summary

A simple, selective, and stability-indicating reverse phase liquid chromatographic method has been developed and validated for the simultaneous determination of impurities and forced degradation products of quetiapine fumarate. The chromatographic separation was achieved on Inertsil-3 C8, 150 mm × 4.6 mm, 5 μm column at 35°C with UV detection at 217 nm using gradient mobile phase at a flow rate of 1.0 mL/min. Mobile phase A contains a mixture of 0.01 M di-potassium hydrogen orthophosphate (pH 6.8) and acetonitrile in the ratio of 80:20 (v/v), respectively, and mobile phase B contains a mixture of 0.01 M di-potassium hydrogen orthophosphate (pH 6.8) and acetonitrile in the ratio of 20:80 (v/v), respectively. The drug product was subjected to the stress conditions of oxidative, hydrolysis (acid and base), hydrolytic, thermal, and photolytic degradation. Quetiapine fumarate was found to degrade significantly in acid, base, and oxidative stress conditions. The degradation products were well resolved from main peak and its impurities. The mass balance was found to be in the range of 96.6–102.2% in all the stressed conditions, thus proved the stability-indicating power of the method. The developed method was validated as per ICH guidelines with respect to specificity, linearity, limit of detection and quantification, accuracy, precision, and robustness.

Open access

Summary

Root exudates were obtained from three mangrove species, viz. Bruguiera gymnorrhiza, Excoecaria agallocha, and Heritiera fomes. Spot tests revealed the presence of, presumably, phenolic compounds in the exudates. Paper chromatography revealed two spots each for B. gymnorrhiza and H. fomes and a single spot for E. agallocha. GC-MS analysis suggested the presence of aminopyrine, palmitic acid, stearic acid, di-n-propyl ether, and 2,5-anhydrogluconic acid in B. gymnorrhiza exudates, aminopyrine and palmitic acid in E. agallocha exudates, and aminopyrine, palmitic acid, and 2,5-anhydrogluconic acid in H. fomes exudates.

Open access

Twenty-four promising drought tolerant genotypes of IRRI and different parts of India were evaluated for genetic variability and drought susceptibility index (DSI) for 12 quality characters and grain yield under irrigated (E1) and drought (E2) conditions. In the present study differences among the genotypes are highly significant for all the characters; between the environments head rice recovery, alkali spreading value, water uptake, kernel length after cooking and yield were significant, while genotype × environment interaction was only significant for hulling, milling, head rice recovery and water uptake. Head rice recovery, alkali spreading value, water uptake and amylose content were observed to be governed by additive gene action under both the environments. Grain yield was positively correlated with kernel width and amylose content under stress environment while, kernel width was positively correlated with hulling and milling and kernel length was correlated with amylose content. The path coefficient analysis revealed that only kernel width in both the environments and amylose content in E2 had positive direct effect on yield. Most of the genotypes expressed low DSI value (<1) for yield and quality characters. However, Swarna and IR 78877-181-B-1-2 were identified as stable genotypes with low DSI value for seed yield and quality characters.

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Diploid wheat T. monococcum L. is a model plant for wheat functional genomics. A soft glume mutant was identified during manual screening of EMS-treated M2 progenies of a T. monococcum accession pau14087. The seeds in the mature spike of the mutant could be easily threshed manually. The soft glume mutant with high sterility, tapering and broader spikes had also tougher rachis than the wild type parent. Genetic analysis of crosses of the mutant with wild type indicated that the mutant was monogenic recessive. To map the soft glume mutant, a mapping population was developed by crossing the soft glume mutant with wild Triticum boeoticum acc. pau 5088, having tough glumes and hard threshing. The soft glume mutant was mapped between SSR markers Xgwm473 and Xbarc69 on 7AmL chromosome of T. monococcum, with a genetic distance of 1.8 cM and 8.3 cM, respectively. The soft glum mutant mapped on 7AmL, being distinct from a previously mapped soft glume mutant in wheat, has been designated as sog2. The work on fine mapping of sog2 gene is in progress.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
Y. Gautam
,
A. Sharma
,
S. Sharma
,
K. Rao
,
J. Kumar
,
V. Kumar
,
B. Singh
,
A. Kumar
, and
A. Hedge

Abstract  

Atmospheric tritium activity is measured regularly around Narora Atomic Power Station (NAPS) since gaseous waste, which contains tritium, is being released through a 145 m high stack at NAPS site. Atmospheric data collected during 2004–2008 shows a large variation of 3H concentration in air, fluctuating in the range of ≤0.2–91.6 Bq m−3. Significantly, higher tritium levels were measured in samples near the site boundary (1.6 km) of NAPS compared to off-site locations. The atmospheric dilution factor was found to be in the range of 1.1 × 10−7–7.3 × 10−7 s m−3. The scavenging ratio of NAPS site was found to be varying from 0.2 × 104 to 14.1 × 104 (Bq m−3 rain water per Bq m−3 air). The inhalation dose to a member of general public at different distances (1.6–30 km) from NAPS site was found to be ranged from 0.08–0.21 μSv year−1.

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A purified alkaline thermo-tolerant bacterial lipase from Pseudomonas aeruginosa MTCC-4713 was immobilized on a poly (AAc-co-HPMA-cl-MBAm) hydrogel. The hydrogel-bound lipase achieved 93.6% esterification of ethanol and propionic acid (300 mM: 100 mM) into ethyl propionate at temperature 65oC in 3 h in the presence of a molecular sieve (3 Å). In contrast, hydrogel-immobilized lipase pre-exposed to 5 mM of HgCl2 orNH4Cl resulted in approximately 97% conversion of reactants in 3 h into ethyl propionate under identical conditions. The salt-exposed hydrogel was relatively more efficient in repetitive esterification than the hydrogel- bound lipase not exposed to any of the cations. Moreover, bound lipase exposed Hg2+ or NH4 + ions showed altered specificity towards p-nitrophenyl esters and was more hydrolytic towards higher C-chain p-nitrophenyl esters (p-nitrophenyl laurate and p-nitrophenyl palmitate with C 12 and C 16 chain) than the immobilized lipase not exposed to any of the salts. The later showed greater specificity towards p-nitrophenyl caprylate (C 8).

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