Security Threats and Challenges for Wireless Sensor Network

A wireless sensor network is a network of a large number of independently working small sensing units which can communicate wirelessly. The basic plan of a Wireless sensor network (WSN) is to structural distribute self-determining devices using sensors to monitor physical or environmental conditions. Wireless communication technology performance different forms of security threats. WSN need effective security mechanisms because of these networks deployed in untended environments. Due to fixed limitations in wireless sensor networks, security is a crucial issue. The intent of this paper is to investigate the security-related threats and challenges in wireless sensor networks. The threats faced by this WSN are similar but not limited to those observed in a simple network of computers or Internet.We identify thesensorsecuritythreats, review proposed security mechanisms for wireless sensor networks

­­Eleven tips for operational researchers working with health programmes: our experience based on implementing differentiated tuberculosis care in south India

Due to the workload and lack of a critical mass of trained operational researchers within their ranks, health systems and programmes may not be able to dedicate sufficient time to conducting operational research (OR). Hence, they may need the technical support of operational researchers from research/academic organisations. Additionally, there is a knowledge gap regarding implementing differentiated tuberculosis (TB) care in programme settings. In this ‘how we did it’ paper, we share our experience of implementing a differentiated TB care model along with an inbuilt OR component in Tamil Nadu, a southern state in India. This was a health system initiative through a collaboration of the State TB cell with the Indian Council of Medical Research institutes and the World Health Organisation country office in India. The learnings are in the form of eleven tips: four broad principles (OR on priority areas and make it a health system initiative, implement simple and holistic ideas, embed OR within routine programme settings, aim for long-term engagement), four related to strategic planning (big team of investigators, joint leadership, decentralised decision-making, working in advance) and three about implementation planning (conducting pilots, smart use of e-tools and operational research publications at frequent intervals). These may act as a guide for other Indian states, high TB burden countries that want to implement differentiated care, and for operational researchers in providing technical assistance for strengthening implementation and conducting OR in health systems and programmes (TB or other health programmes). Following these tips may increase the chances of i) an enriching engagement, ii) policy/practice change, and iii) sustainable implementation

Transparent and Flexible Mn 1−

Control over the fabrication of state-of-the-art portable pseudocapacitors with the desired transparency, mechanical flexibility, capacitance, and durability is challenging, but if resolved will have fundamental implications. Here, defect-rich Mn1−x−y(CexLay)O2−δ ultrathin films with controllable thicknesses (5–627 nm) and transmittance (≈29–100%) are fabricated via an electrochemical chronoamperometric deposition using a aqueous precursor derived from end-of-life nickel-metal hydride batteries. Due to percolation impacts on the optoelectronic properties of ultrathin films, a representative Mn1−x−y(CexLay)O2−δ film with 86% transmittance exhibits an outstanding areal capacitance of 3.4 mF cm−2, mainly attributed to the intercalation/de-intercalation of anionic O2− through the atomic tunnels of the stratified Mn1−x−y(CexLay)O2−δ crystallites. Furthermore, the Mn1−x−y(CexLay)O2−δ thin-film device exhibits excellent capacitance retention of ≈90% after 16 000 cycles. Such stability is associated with intervalence charge transfer occurring among interstitial Ce/La cations and Mn oxidation states within the Mn1−x−y(CexLay)O2−δ structure. The energy and power densities of the transparent flexible Mn1−x−y(CexLay)O2−δ full-cell pseudocapacitor device, is measured to be 0.088 μWh cm−2 and 843 µW cm−2, respectively. These values show insignificant changes under vigorous twisting and bending to 45–180° confirming these value-added materials are intriguing alternatives for size-sensitive energy storage devices.</p