Zinc ferrite nanoparticles of different sizes ranging from 12 to 62 nm were synthesized by using the nitrate route. These nanoparticles were irradiated by a 100 MeV oxygen beam at two fluences: 1 × 10 13 and 5 × 10 13 ions/cm 2 . It was observed that modes corresponding to cubic spinel phase were retained after the irradiation in all the systems. The variation in the parameters of various modes follows phonon confinement, while this effect seems to violate in irradiated specimen. It was found that the irradiation-induced changes in the modes F 2g (2) and F 2g (3) depend on whether the crystallite size of the pristine sample is less than, equal to or greater than the phonon confinement length, while this length is not dominant for the irradiation-induced changes in the mode A 1g . The changes in various parameters of the modes are attributed to the combined effect of the restructuring of the chemical species and ion-induced defects.

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Cisplatin treatment of rats results into a significant increase in the activity of Ca(2+)-independent nitric oxide synthase (NOS) in kidneys and liver. Significant enhancement of lipid peroxidation in gastric mucosa, kidneys and liver was also observed. The administration of NG-nitro-L-arginine methyl ester, an inhibitor of NOS, markedly reduced renal and gastrointestinal toxicity, and also decreased the content of blood urea nitrogen, serum creatinine, and incidence of diarrhoea along with a significant inhibition in lipid peroxidation in the target organs. The present report, while demonstrating the beneficial effect of the blockade of NO pathways during cisplatin chemotherapy, may be helpful in developing strategies for combating some of the toxic side-effects of the drug.

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A special type of metal side disk rotating electrode has been demonstrated for the direct estimation of total arsenic [As(III) and As(V)] at low ppb (mg/L) level using anodic stripping differential pulse voltammetry (ASDPV). A conventional three electrodes cell is used equipped with side disk rotating gold electrode as working, graphite/ platinum electrode as auxiliary and Ag/AgCl/3M KCl as reference electrodes. Arsenic is estimated in various acidified samples without any digestion, containing a trace amount of copper at low ppb level. The major problems associated with ASDPV of high acidic condition (acid hazards), irreproducible results due to the interference of hydrogen bubbles, evolved at the cathode during the deposition of arsenic in acidified samples and poor detection level are overcome with the help of the specially designed gold side disk rotating electrode and modified electrolyte. The presence of a trace amount of copper(II) salt in the electrolyte is found to enhance the sensitivity of the technique. The shape and position of the metal disk at the electrode, rotation speed of the electrode and electrolyte are optimized to have less hydrogen gas bubbles interference and high reproducibility in the detection of arsenic up to 2 ppbAE 15% level in various samples. The electrode has been found very stable and reproducible even for more than 200 estimations.