Perfluorinated ionomer membranes have been the topic of a tremendous amount of research for over three decades due to their use as the predominant membrane system for proton exchange membrane fuel cell (PEMFC) applications. Their excellent physical properties, including high proton conductivity, oxidative and reductive stability, and mechanical properties, have enabled the PEMFC to reach the levels of performance achieved to date. However, the demands on the fuel cell system are increasing as new applications loom with their needs for lower cost, higher performance, and flexibility to accommodate new fuels. System demands are pushing operating temperatures higher, causing the water balance and humidification of the perfluorinated ionomer membrane to become important issues. This section reviews the status of research and development activities around the Nafion ® perfluorinated ionomer membrane and Nafion ® solutions. The focus of the review is on the measurement of physical property data and new insights into the mechanisms of conduction in these systems. An attempt is made to summarize recent structural studies and characterization techniques that are bringing new insights into the conduction process, as well as recent efforts in mathematical modeling and computer simulations of the conduction process. Finally, membrane‐related issues that arise in the direct methanol PEMFC are reviewed and data on methanol transport in Nafion ® membranes are summarized.

BACKGROUNDFat patch grafting is a simple effective alternative to conventional tympanoplasty in dealing with carefully selected small central tympanic membrane perforations. Despite its numerous advantages and relative ease of the procedure, many a times it has been underused. MATERIALS AND METHODSThe study was conducted in the Department of Otolaryngology, Academy of Medical Sciences, Pariyaram, Kannur, Kerala over a period of 2 years on 44 ears. An endoscope-assisted fat patch grafting technique was used in our study. RESULTSThe Male-to-Female ratio was 2.1: 1; 39 cases had complete closure of the perforation. So, the overall success rate of the study was around 89%. CONCLUSIONFat graft myringoplasty is a simple, cost effective day care surgical procedure done under local anaesthesia. It is an under-utilised procedure by otologists for the treatment of tympanic membrane perforations. Through our study, we would like to emphasise the importance of this procedure done endoscopically for carefully selected cases, which has a very good success rate.

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