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The photoluminescence studies were carried out for Pr3+ ion-doped NaBaB9o15 phosphors by varying Pr3+ ion concentrations. The formation of single-phase was confirmed through X-Ray diffraction analysis. FTIR analysis was made to identify functional groups presented in the studied phosphors. The morphology of synthesized phosphors was examined through SEM analysis. As-prepared NaBaB9O15:xPr3+ phosphors exhibit strong red emission peak with FWHM of 14 nm under blue excitation. In the studied phosphors, optimum dopant (Pr3+ ions) concentration was found as 4 mol%. The CIE method was employed to find dominant giving out color of prepared phosphors. The color coordinates are passed through red region of CIE diagram and hence, the studied NBB:xPr3+ phosphors have the ability to emit intense red color under blue excitation. Decay measurements are made to determine the fluorescent lifetime values of 1D2 excited level of Pr3+ ions and the decay curves are well fitted to non-exponential curve fitting method. All the measurements were done as a function of Pr3+ ion concentration at room temperature and the results were compared with similar literature results. [ABSTRACT FROM AUTHOR]

High night temperature (HNT) impairs crop productivity through the reproductive failure of gametes (pollen and pistil). Though female gametophyte (pistil) is an equal partner in the seed-set, the knowledge of the antioxidant system(s) and hormonal control of HNT tolerance or susceptibility of pistils is limited and lacking. The objectives of this study were to determine the antioxidant mechanism for homeostatic control of free radicals, and the involvement of abscisic acid (ABA) and gibberellic acid (GA3) in HNT stress protection in the wheat pistils of contrasting wheat genotypes. We hypothesized that HNT tolerance is attributed to the homeostatic control of reactive oxygen species (ROS) and hormonal readjustment in pistils of the tolerant genotype. The ears of two contrasting wheat genotypes—HD 2329 (susceptible) and Raj 3765 (tolerant) were subjected to two HNTs (+5 °C and +8 °C) over ambient, in the absence and presence of dimethylthiourea (DMTU), a chemical trap of hydrogen peroxide (H2O2). Results showed that HNTs significantly increased ROS in pistils of susceptible genotype HD 2329 to a relatively greater extent compared to tolerant genotype Raj 3765. The response was similar in the presence or absence of DMTU, but the H2O2 values were lower in the presence of DMTU. The ROS levels were balanced by increased activity of peroxidase under HNT to a greater extent in the tolerant genotype. Cytosolic glyceraldehyde-3-phosphate dehydrogenase (GAPC) activity was inversely related to H2O2 production within a critical range in Raj 3765, indicating its modulation by H2O2 levels as no change was observed at the transcriptional level. The hormonal status showed increased ABA and decreased GA3 contents with increasing temperature. Our study elucidates the role of H2O2 and GA3 in stress tolerance of pistils of tolerant genotype where GAPC acts as a ROS sensor due to H2O2-mediated decrease in its activity. [ABSTRACT FROM AUTHOR]

The study of trap generation during high voltage stressing of thin oxide films reveals that high field emission processes generate the traps inside the oxide. The study is performed by the coupling of the trap generation process to the statistical features of breakdown. The wearout and breakdown of oxides is revealed by this study.

The time-to-breakdown, number of traps generated and charge-to-breakdown of thin silicon oxide films stressed with positive and negative bipolar pulses are evaluated and compared to unipolar stressed oxide films with constant dc voltages. The three parameters of bipolar stressed oxide films increase with an increase in an opposite polarity pulse that eventually becomes the stressing pulse. The traps generated from the various interfaces of the films differ in spatial arrangements.

In a multicenter study conducted by the Indian Council of Medical Research, 1,646 samples of wheat grain collected from rural and urban areas of 10 states representing different geographical regions of India were analyzed for aflatoxin (AFBI). AFB, concentrations of ⩾5 µg kg-1 were recorded in 40.3% of the samples, and concentrations above the Indian permissible regulatory limit of 30 µg kg-1 were found in 16% of the samples. The proportion of samples with AFB1 concentrations above the Indian regulatory limit ranged from 1.7 to 55.8% in different states, with the minimum in Haryana and the maximum in Orissa. The variation in wheat contamination among states seems to be mainly the result of unsatisfactory storage conditions. Median AFB1 concentrations of 11, 18, and 32 µg kg-1 were observed in samples from Uttar Pradesh, Assam, and Orissa, respectively; concentrations in other states were <5 µg kg-1. The maximum AFB1 concentration of 606 µg kg-1 was observed in a sample from the state of Uttar Pradesh. The calculated probable daily intakes of AFB, through consumption of contaminated wheat for the population in some states were much higher than the suggested provisional maximum tolerable daily intake. Human health hazards associated with such AFB1 exposure over time cannot be ruled out. [ABSTRACT FROM AUTHOR]

Under a multi-centre study conducted by the Indian Council of Medical Research, 1511 samples of parboiled rice were collected from rural and urban areas of 11 states representing different geographical regions of India. These samples were analysed for contamination with aflatoxin B 1. The presence of aflatoxin B 1 at levels?=?5?µg?kg -1 was found in 38.5% of the total number of samples of the parboiled rice. About 17% of the total samples showed the presence of aflatoxin B 1 above the Indian regulatory limit of 30?µg?kg -1 . No statistically significant difference in percentage of samples contaminated with >30?µg?kg -1 was observed between pooled rural (19.4%) and urban (14.5%) data. A median value of 15?µg?kg -1 of aflatoxin B 1 was observed in samples from Assam, Bihar and Tripura. In all other states surveyed the median value was [ABSTRACT FROM AUTHOR]

Under a multicentre study conducted by the Indian Council of MedicalResearch, 2074 samples of maize were collected from rural and urban areas of 11 states representing different geographical regions of thecountry. These samples were analysed for aflatoxin B{sub}1{end} using the AOAC method. Analytical quality assurance between various participating laboratories was ensured through analysis of check-samples. About 26% of maize samples collected from 11 states exceeded the permissible Indian regulatory limit of 30 mu g kg{sup}-1{end}. No statistically significant difference in percentage of samples contaminated (greater than 30 mu g kg{sup}-1{end}) was observed between pooled rural (27.8%) and urban (23.7%) data. The maximum level of contamination of 666 mu g kg{sup}-1{end} was observed in the state of Haryana. The median level of less than 5 mu g kg{sup}-1{end} was observed in the states of Gujarat, Haryana, West Bengal, Andhra Pradesh and Karnataka.In all other states studied the median level was found to vary between 10 and 35 mu g kg{sup}-1{end}. [ABSTRACT FROM AUTHOR]

Under a multicentre study conducted by the Indian Council of Medical Research, 2062 samples of groundnut were collected from rural and urban areas of 11 states representing different geographical regions of the country. These samples were analysed for aflatoxin B1 using the AOAC method. Analytical quality assurance between various participating laboratories was ensured through analysis of check-samples. Twenty-one per cent of groundnut samples collected from 11 states exceeded the permissible Indian regulatory limit of 30 micrograms/kg. No statistically significant difference in percentage of samples contaminated (> 30 micrograms/kg) were observed between pooled rural (22.9%) and urban (19.9%) data. Amongst the 11 states, the minimum and maximum per cent contamination respectively (> 30 micrograms/kg) was observed to be 15.2 in the state of Andhra Pradesh and 28.3 in the state of Haryana. The maximum level of contamination of 833 micrograms/kg was observed in the state of Gujarat. The median level of < 5 micrograms/kg was observed in the states of Gujarat, Haryana, Punjab, Andhra Pradesh and Karnataka. In all other states studied, the median level was found to vary between 10 and 20 micrograms/kg. The 90th percentile values were high in Andhra Pradesh (125 micrograms/kg), Gujarat (111 micrograms/kg) and Haryana (110 micrograms/kg). In the remaining states the 90th percentile value ranged from 60 to 93 micrograms/kg. Analysis of pooled data showed the percentages of samples exceeding the level of contamination of 5 micrograms/kg and 15 micrograms/kg, respectively were 44.9% and 37.4% which therefore, showed a marked increase when compared with the per cent of samples exceeding 30 micrograms/kg in the overall data.