An Overview and Assessment of Wireless Technologies and Co- existence of ZigBee, Bluetooth and Wi-Fi Devices

AbstractWi-Fi, ZigBee and Bluetooth wireless communication systems utilize the Industrial Scientific and Medical-(ISM) Band, which results in a high mutual interference between these technologies since they all these systems operate at the same or very close frequency bands. The interference problem increases with an in-device Co-existence (technologies existing on same device). This is primarily due to the characteristics of each technology such as access mechanism, frame structure, peak transmit power and frequency of operation. This work describes the interference between the Wi-Fi mostly as an aggressor on Bluetooth and ZigBee wireless networks. So the experimental analysis of the coexistence of these three technologies in an assumed home environment is studied especially when ZigBee is enabled for a Home Automation Network where there could be close proximity of Wi-Fi and Bluetooth devices such as PDAs and mobile phones. The obtained result shows that there is severe degradation on ZigBee and Bluetooth packet transmission of packets as well as re-transmission of ZigBee packets when Wi-Fi is operating

Shelf Life Study and Quality Attributes of Cocoyam Chips

The study was carried out to determine changes in the quality indices (levels of peroxides values, acid values, pH and colour) of cocoyam chips and microbiological safety (bacterial, yeast and mould counts) of cocoyam chips as influenced by temperature during storage period of fried cocoyam chips. Cocoyam tubers were processed into chips of 3mm thickness; the slices were then fried at a frying temperature of 170°C in a shallow pot for 7 minutes and was packaged in polyethylene bags and stored under room and refrigerator temperature. The results showed that there was significant difference (p≤0.05) between quality indices, microbiological safety and storage temperature and packaging materials. From week 0-5, peroxide values of samples stored under refrigeration temperature were found to be low, ranged from 3.39 - 11.58 meq kg-1, while the samples stored in the room temperature were found to be higher 3.81 - 12.87 meq kg-1. Acid values were also found to be low in the samples stored in the refrigerator, ranged from 5.79 - 16 3.34mg/g and the samples that were stored in the room temperature ranged from 9.94 - 24.05mg/g. The samples stored under refrigeration temperature had low bacterial counts ranged from 5.0 x 101 - 6.2 x 101 cfu/ml while samples stored in the room temperature had higher bacterial counts, ranged from 9.0 x 101 – 74 x 101 cfu/ml. Yeast and mould counts in samples stored under refrigeration temperature ranged from 4.0 x 101 - 32 x 10 cfu/ml while the samples that were stored in room temperature had higher counts, ranged from 3.0 x 10 – 38 x 10 cfu/ml. pH ranged between 6.88 - 7.02 for both samples during storage period. The results showed that storage temperature and properly sealed packaging material has effect on the above parameters that were determined. There were also colour changes during the storage period

Genome biology of the paleotetraploid perennial biomass crop Miscanthus

Miscanthus is a perennial wild grass that is of global importance for paper production, roofing, horticultural plantings, and an emerging highly productive temperate biomass crop. We report a chromosome-scale assembly of the paleotetraploid M. sinensis genome, providing a resource for Miscanthus that links its chromosomes to the related diploid Sorghum and complex polyploid sugarcanes. The asymmetric distribution of transposons across the two homoeologous subgenomes proves Miscanthus paleo-allotetraploidy and identifies several balanced reciprocal homoeologous exchanges. Analysis of M. sinensis and M. sacchariflorus populations demonstrates extensive interspecific admixture and hybridization, and documents the origin of the highly productive triploid bioenergy crop M. x giganteus. Transcriptional profiling of leaves, stem, and rhizomes over growing seasons provides insight into rhizome development and nutrient recycling, processes critical for sustainable biomass accumulation in a perennial temperate grass. The Miscanthus genome expands the power of comparative genomics to understand traits of importance to Andropogoneae grasses