Survey on Wireless Sensor Network Applications and Energy Efficient Routing Protocols

Wireless sensor network (WSN) is a group of small power-constrained nodes that sense data and communicate it to the base station (BS). These nodes cover a vast region of interest (ROI) for several purposes according to the application need. The first challenge encountered in WSNs is how to cover the ROI perfectly and send the monitored data to the BS. Although the energy introduced during setup phase and the violation of energy fairness constraint of dynamic routing topologies, they achieve high network performance in terms of coverage and connectivity. In this paper, we categorize the applications of WSN based on different aspects to show the major protocol design issues. Thus, the energy efficiency of the recent proactive routing protocols is studied from different angles. The energy overhead and energy fairness of each protocol were carefully analyzed. The most energy efficient routing protocols for homogeneous proactive networks were studied and compared to highlight the research challenges and existing problems in this area. The results proved that energy overhead and route selection are the most effective aspects of network lifetime and network efficiency.

     

Intercellular induction of apoptosis signalling pathways

Intercellular signalling plays an important role in the progression of a transformed cell to a tumour. In order to characterise the underlying mechanisms, a well-defined model cell system of intercellular induction of apoptosis was used where neighbouring normal cells can selectively eliminate transformed cells. In the absence of non-transformed cells, the induction of apoptosis in transformed 208Fsrc3 cells occurs via autocrine destruction and is dominated by peroxidase (PO), which initiates the PO/hypochlorous acid signalling pathway at high local cell densities. However, when the transformed cells are co-cultured with the non-transformed 208F cells, apoptosis in transformed cells additionally occurs as a result of intercellular signalling with the non-transformed cells and is predominantly due to the production of nitric oxide (NO(?)), which initiates the NO(?)/peroxynitrite pathway.