Polypyrrole (PPy) and polypyrrole/cerium oxide nanocomposite (PPy/CeO2) were prepared by the chemical oxidative method in an aqueous medium using anhydrous ferric chloride (FeCl3) as an oxidant. The successful formulation of materials was confirmed by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and transmittance electron microscopy (TEM). A four-in-line probe device was used for studying DC electrical conductivity and ammonia vapor sensing properties of PPy and PPy/CeO2. The significant improvement in both the conductivity and sensing parameters of PPy/CeO2 compared to pristine PPy reveals some synergistic/electronic interaction between PPy and cerium oxide nanoparticles (CeO2 NPs) working at molecular levels. The initial conductivity (i.e., conductivity at room temperature) was found to be 0.152 Scm-1 and 1.295 Scm-1 for PPy and PPy/CeO2, respectively. Also, PPy/CeO2 showed much better conductivity retention than pristine PPy under both the isothermal and cyclic ageing conditions. Ammonia vapor sensing was carried out at different concentration (0.01, 0.03, 0.05, 0.1, 0.2, 0.3, 0.4, and 0.5 vol %). The sensing response of PPy/CeO2 varied with varying concentrations. At 0.5 vol % ammonia concentration, the % sensing response of PPy and PPy/CeO2 sensor was found to be 39.1% and 93.4%, respectively. The sensing efficiency of the PPy/CeO2 sensor was also evaluated at 0.4. 0.3, 0.2, 0.1, 0.05, 0.03, and 0.01 vol % ammonia concentration in terms of % sensing response, response/recovery time, reversibility, selectivity as well as stability at room temperature.
Despite the availability of international recommendations for the management of Infantile Epileptic Spasms Syndrome (IESS), there is a lack of recommendations adapted to the local context of clinical practice of pediatric neurology in the Gulf Cooperation Council (GCC) countries. By an initiative from the Saudi Pediatric Neurology Society (SPNS), a literature review was performed and an expert panel comprised of 13 pediatric neurologists from all GCC countries (Saudi Arabia, Kuwait, Bahrain, Oman, Qatar, and the United Arab Emirates) was subsequently convened to discuss all issues related to the management and diagnosis practices of IESS in the GCC. The overall aim of this consensus document was to develop practical recommendations to support the care of patients with IESS in the GCC and to reflect on how clinical management approaches compare with those adopted internationally.