DESIGN ISSUES AND CLASSIFICATION OF WSNS OPERATING SYSTEMS

Wireless Sensor Networks is an emerging area of research. Wireless Sensor networks (WSNs) face lot of problems that do not arise in other types of wireless networks and computing environments. Limited computational resources, power constraints, low reliability and higher density of sensor nodes (motes) are just some basic problems that have to be considered when designing or selecting a new operating system in order to evaluate the performance of wireless sensor nodes (motes). In this paper we focused on design issues, challenges and classification of operating systems for WSNs

Optimization of xylanase production from <i style="mso-bidi-font-style:normal">Melanocarpus albomyces</i> using wheat straw extract and its scale up in stirred tank bioreactor

282-289Production of xylanase from agro-industrial by-product such as wheat straw has been optimized. The wheat straw is subjected to heat treatment under mild alkaline conditions for the extraction of xylo-oligosaccarides, which serve as both an inducer and a carbon source for fungal growth and xylanase production under submerged fermentation. The statistical approach of response surface methodology has been employed for the optimization of different nitrogen sources. The production of xylanase is influenced by the synergic effect of nitrogen sources in the fermentation medium. Further optimization of other factors such as inoculum age, inoculum size, initial pH, growth temperature and agitation significantly enhance xylanase activity to about 425 ± 5 IU/mL in shake flask using optimized fermentation medium and conditions. The scale up of fermentation process up to 14 L bioreactor yields a maximum xylanase activity of about 520 IU/mL in 36 h of fermentation which is 1.22-fold higher than that obtained at shake flask level

Spray-drying of xylanase from thermophilic fungus <i style="mso-bidi-font-style:normal">Melanocarpus albomyces</i>–Effect of carriers and binders on enzyme stability

89-95A spray-dried powder formulation obtained from the fermentation broth of the fungus has been developed. The effect of different additives (carriers and binders) on thermal deactivation of xylanase has been evaluated at 60°C. Addition of carriers and binders improves half-life by 6.6-7.0 folds, whereas the synergistic effect of carrier and binder enhances the half-life by 27.5 folds. Under the optimized conditions of the spray-drying process, retention of 99.4% specific activity is obtained with the maximum powder recovery of 62.4% at 140/65.2°C inlet/outlet temperature. The final spray dried powder produced is found to be brownish, free flowing and non-hygroscopic. The shelf-life of spray-dried powder is 202 days at 30°C, making it industrially useful product. </span