Probing the multifunctional behaviour of barium zirconate/barium titanate/epoxy resin hybrid nanodielectrics

In this study, hybrid composite nanodielectrics of epoxy resin and BaZrO3/BaTiO3 ceramic nanoparticles were prepared via a mixing process varying the filler content. Composites\u27 morphology was studied via scanning electron microscopy, and in all cases, fine nanodispersions were detected. The electrical response of the employed nanofillers, as well as of the produced hybrid composite specimens, was examined by means of broadband dielectric spectroscopy in a wide temperature and frequency range. The thermally varying polarization of the embedded nanoparticles induces functionality to the prepared composite systems, due to the thermally triggered structural transitions of BaZrO3 and BaTiO3. Aiming to investigate these structural transitions, samples were studied by means of X-Ray diffraction with temperature as a parameter. Finally, the ability of the examined nanosystems to store and harvest energy under various conditions was determined and discussed in tandem with the mutual interactions of the occurring physical mechanisms at specific temperature ranges

Restless legs syndrome in hemodialysis patients: an epidemiologic survey in Greece

Background: Restless legs syndrome (RLS) is a sensorimotor disorder characterized by an uncontrolled need to move extremities accompanied by unpleasant sensations, which frequently leads to sleep disturbances. In hemodialysis (HD) patients, the previously reported RLS prevalence varied enormously, between 6% and 60%. In our study, we investigated the RLS prevalence in HD patients for the first time in Greece. Methods: A continuous sample of HD patients was studied between January and September of 2010 in six dialysis units in Greece. RLS diagnosis was based on the essential clinical criteria of the International RLS Study Group (IRLSSG). The standardized incidence ratio (SIR) for RLS in HD patients was calculated in comparison to data from a recent survey of the general population in Greece. Results: In our study of 579 HD patients in Greece (236 women; mean age, 65 +/- 13 years), the prevalence of RLS was elevated in comparison to the general population (26.6% vs 3.9%), with an SIR of 5.4 (95% confidence interval [CI], 4.6-6.3). In the fully adjusted model, the risk for RLS in HD patients was reduced in older age (odds ratio [OR], 0.98 [95% CI, 0.96-0.99]) and increased in women (OR, 1.60 [95% CI, 1.05-2.43]) in cases with elevated levels of beta(2) microglobulin (OR, 1.15 [95% CI, 1.01-1.32]) and intact parathormone (iPTH) (OR, 1.30 [95% CI, 1.08-1.56]). Conclusion: A high RLS prevalence was recorded in a large HD population in Greece, clearly suggesting the need for enhanced awareness of RLS in nephrology. The RLS risk was increased in women and in younger HD patients as well as in those with elevated beta(2) microglobulin and iPTH levels. (C) 2013 Published by Elsevier B.V