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Copyright of Synergies Inde is the property of GERFLINT (Groupe d'Etudes et de Recherches pour le Francais Langue Internationale) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Analysis of wide bandgap compound semiconductors for high frequency and high power unipolar electronic devices indicates that intermetallics, diamond and compounds such as AlN, ZnO, GaN and InN enhance the magnitude of on-resistance. The improvement in resistance facilitates high temperature operations.

Copyright of Synergies Inde is the property of GERFLINT (Groupe d'Etudes et de Recherches pour le Francais Langue Internationale) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

ABSTRACT Heavy metals are known for their associated nephrotoxicity and nickel is no exception. An integrated metabonomic approach, based on high-resolution 1H NMR spectroscopy, was applied to determine the acute biochemical effects of NiCl2 on the renal tissues of rats. Kidney homogenates from rats treated with NiCl2 at two dose levels (4 and 20 mg kg−1 b.w., i.p.) and those from controls were analysed using 1H NMR spectroscopy and also assessed for antioxidant parameters at days 1, 3 and 5 post-dose. The major metabolite changes corresponding to nickel exposure were related to amino acids, osmolytes and energy metabolites. Differential responses were observed in 1H NMR spectra with exposure to low and high doses of NiCl2. For high doses, 1H NMR spectral analysis revealed alterations in renal tissues, along with damage to the cortical and papillary region and depletion of renal osmolytes such as betaine, trimethyl amine oxide, myo-inositol and taurine, which persisted until day 5 post-dose. The metabolite profile of 1H NMR spectra obtained from animals treated with lower dose of NiCl2 initially increased as an immediate stress response and then showed signs of recovery with the passage of time. NMR spectral analysis was well corroborated with histopathological and oxidative stress results. Nickel-induced oxidative stress was observed in both groups of animals with increased levels of antioxidant parameters at initial time points, but continued to increase in the high-dose group. The present study shows a huge potential of metabonomics for mapping organ-based metabolic response during heavy metal toxicity. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

An essay is presented on Lemuria, an imagined lost continent located in the Indian and Pacific oceans. It examines how the foundational myth of this continent constituted a powerful counter-narrative to colonial and postcolonial settlement. It discusses how the work of writer Robert-Edward Hart constructs a male subject that is linked with the nurturing earth. It explores the works of contemporary writer Ananda Devi who shows the island as claustrophobic, miserable, and hellish space.

The increasing threat of nuclear terrorism or radiological accident has made high throughput radiation biodosimetry a requisite for the immediate response for triage. Owing to detection of subtle alterations in biological pathways before the onset of clinical conditions, metabolomics has become an important tool for studying biomarkers and the related mechanisms for radiation induced damage. Here, we have attempted to combine two detection techniques, LC-MS and 1 H NMR spectroscopy, to obtain a comprehensive metabolite profile of urine at 24 h following lethal (7.5 Gy) and sub-lethal (5 Gy) irradiation in mice. Integrated data analytics using multiblock-OPLSDA (MB-OPLSDA), correlation networking and pathway analysis was used to identify metabolic disturbances associated with radiation exposure. MB-OPLSDA revealed better clustering and separation of irradiated groups compared with controls without overfitting ( p -value of CV-ANOVA: 1.5 × 10 -3 ). Metabolites identified through MB-OPLSDA, namely, taurine, creatine, citrate and 2-oxoglutarate, were found to be dose independent markers and further support and validate our earlier findings as potential radiation injury biomarkers. Integrated analysis resulted in the enhanced coverage of metabolites and better correlation networking in energy, taurine, gut flora, L-carnitine and nucleotide metabolism observed post irradiation in urine. Our study thus emphasizes the major advantage of using the two detection techniques along with integrated analysis for better detection and comprehensive understanding of disturbed metabolites in biological pathways.

Heavy metals are known for their associated nephrotoxicity and nickel is no exception. An integrated metabonomic approach, based on high-resolution (1) H NMR spectroscopy, was applied to determine the acute biochemical effects of NiCl(2) on the renal tissues of rats. Kidney homogenates from rats treated with NiCl(2) at two dose levels (4 and 20 mg kg(-1) b.w., i.p.) and those from controls were analysed using (1) H NMR spectroscopy and also assessed for antioxidant parameters at days 1, 3 and 5 post-dose. The major metabolite changes corresponding to nickel exposure were related to amino acids, osmolytes and energy metabolites. Differential responses were observed in (1) H NMR spectra with exposure to low and high doses of NiCl(2). For high doses, (1) H NMR spectral analysis revealed alterations in renal tissues, along with damage to the cortical and papillary region and depletion of renal osmolytes such as betaine, trimethyl amine oxide, myo-inositol and taurine, which persisted until day 5 post-dose. The metabolite profile of (1) H NMR spectra obtained from animals treated with lower dose of NiCl(2) initially increased as an immediate stress response and then showed signs of recovery with the passage of time. NMR spectral analysis was well corroborated with histopathological and oxidative stress results. Nickel-induced oxidative stress was observed in both groups of animals with increased levels of antioxidant parameters at initial time points, but continued to increase in the high-dose group. The present study shows a huge potential of metabonomics for mapping organ-based metabolic response during heavy metal toxicity., (Copyright © 2011 John Wiley & Sons, Ltd.)

Incubation of BMG-1 cells with thallium chloride (201Tl) in the range of diagnostic dose did not show a smooth uptake curve and appeared to have an unsuspected deviation in initial phase. In the present study this unexpected phenomenon was explored, using commonly used radionuclides (viz., 201Tl and 131I). Comparison was made with technetium-99m pertechnetate (99mTcO4(-)) and technetium-99m labeled methoxyisobutylisonitrile (99mTc-MIBI) that are known to show conventional 2 phase graph representing inflow and outflow segments. Serial in vitro, ex-vivo and in vivo gamma scintigraphy as well as NMR spectroscopy experiments were conducted to corroborate the results. BMG-1 cells demonstrated a four-phase uptake pattern with 201Tl as compared to a conventional biphasic pattern with 99mTc-MIBI. Flow cytometry data however did not reveal any 201Tl induced cell injury. Further, mice tissue extracts injected with 201Tl also showed a transient depression in its uptake. Scintigraphy experiments in rabbits administered with diagnostic dose of 201Tl and 131I confirmed the in vitro and ex vivo findings. Further, proton NMR spectroscopy showed decrease in the level of choline at 3 h and 24 h in 201Tl treated animals as compared to control. Phosphoethanolamine peak firstly decreased at 3 h but reached normal level at 24 h time point. No significant change was observed in the level of betaine. This transient reduction in internalization of 201Tl and 131I may represent a hitherto unknown acute effect of low dose radiation, i.e., transient depression in Na+-K+ ATPase pump activity without any apparent evidence of cell damage, representing a transient cell membrane dysfunction. The phenomenon may present a mechanistical explanation of 'thyroid stunning' at cellular level and suggest that it may be more universal in nature than suspected till now.