High performance bifunctional electrocatalytic activity of a reduced graphene oxide-molybdenum oxide hybrid catalyst

The rGO–MoO3nanosphere hybrid synthesized exceeds the performance of high quality commercial Pt/C in terms of electrocatalytic activity, stability, durability and CO tolerance.</p

AN IMPROVED CLUSTER BASED ROUTING PROTOCOL WITH BACKUP CLUSTER HEAD FOR MANETS

ABSTRACT Mobile ad hoc network (MANET) is a reconfigurable network of mobile nodes connected by multi-hop wireless links and capable of operating without any fixed infrastructure support. In order to facilitate communication within such self-creating, self-organizing and self-administrating network, a dynamic routing protocol is needed. The routing protocol performance suffers due to resource constraints and mobility of the nodes. The existing routing challenges in MANETs clustering based protocols suffer frequently with cluster head failure problem, which reduces the cluster stability. This paper proposes, Improved CBRP, a method to develop the cluster stability and in-turn enhances the performance of traditional cluster based routing protocol (CBRP), by electing better cluster head using weighted clustering algorithm and considering some vital routing challenges. Also, proposed protocol suggests a backup cluster head for each cluster, to increase the stability of the cluster in case of unexpected failure of cluster head. Keywords: CBRP, MANETs, cluster head, WCA, backup cluster. INTRODUCTION Mobile ad-hoc networks (hereinafter, MANETs) are infrastructure less self-organizing networks, formed randomly by mobile hosts using wireless links, and the union of which forms a communication network. Routing protocol offers communication outside the physical wireless range of nodes by relaying on intermediary nodes Clustering is one approach to reduce traffic during the routing process, and several authors proposed cluster based routing protocols Node starts timer and broadcasts HELLO packet. If it receives a Hello reply from any cluster head then sets it state as cluster member else it makes itself as cluster head but only when it has bidirectional links with one or more neighbor nodes. Otherwise it repeats the procedure with sending HELLO packets. Clustering is the process that divides the network into interconnected substructures, called clusters. Each cluster has a cluster head and act as a coordinator within the substructure. Each cluster head, in other terms acts as

An Intelligent Routing Protocol for MANETs with Efficient Weighted Clustering and Twin-cluster Heads

Mobile Ad hoc Networks (MANET) consisting multiple number of nodes having the feature of wireless communication and networking capability. These nodes are able to communicate with each node irrespective of its frequency range. Being the self- organizing nature, these networks can be formed as well as deformed easily and quickly without installing any centralized infrastructure. These networks have the highest mobility and routes to be updated frequently to ensure that the connections are newer one. The best performance guaranteeing routing protocol is Cluster Based Routing Protocol (CBRP). However, the CBRP has been suffering to sustain its performance due to poor responses from the cluster heads. To overcome this challenge, it is proposed an Intelligent Cluster Based Routing Protocol( ICBRP) having the feature of dualcluster heads which ensures the firmness of clusters and a novel technique for clusterhead selection employing enhanced weighted clustering process. Also, the dualcluster heads are optimized and allowed to work together with better understanding regarding increasing the performance level of clusters, solidity and extension of network lifetime

Incidence and outcome of transplant renal artery stenosis: A single-center experience

Introduction: Transplant renal artery stenosis (TRAS) is a recognized, potentially curable cause of posttransplant arterial hypertension, allograft dysfunction, and graft loss. Aim: This study aims to study the incidence, clinical presentation, and outcome of TRAS in renal allograft recipients. Materials and Methods: This is a retrospective study done at the Institute of Nephrology, Madras Medical College, from January 2009 to November 2016. Demographic data, type of renal donor, and posttransplant evaluation including delayed graft dysfunction, acute rejection, cytomegalovirus status, blood pressure profile, and graft function were studied. Laboratory and investigation data including serum potassium, lipid profile, Doppler transplant renal artery, and angiogram were analyzed. Results: Five hundred and twenty-six renal allograft recipients were studied; 7 patients had TRAS (1.3%). The timeline of TRAS ranged from 3 to 30 months (median: 5 months) after transplant. Three patients (42%) presented with refractory hypertension, six (85%) patients developed allograft dysfunction, and three (42%) patients presented with anuria. All patients were treated with percutaneous transluminal angioplasty with stenting, and one patient had recurrent TRAS after 1 year and treated with balloon angioplasty and stenting. Among seven patients, three patients have normal graft function, three had chronic graft dysfunction, and one patient had graft loss. Conclusion: The incidence of TRAS in the study was 1.3%. Early detection and correction reduce patients morbidity and allograft dysfunction

Progress in Upcycled & Sustainable Robotics: Developing an Accessible, Flexible, and Environmentally Friendly Robotics Platform

The development of a sustainable, environmentally aware and accessible robotic platform to be used in multiple applications is detailed. The robot utilizes upcycled components and serves as an economical and environmentally friendly robotic platform whose sensor loadout can easily be tailored for mission specific needs. The robot could serve as an intelligent system that might be applied to education, safety, environmental remediation, stewardship, physical impairment services, or in active sanitation applications. Some student projects using the platform are also discussed

Synthetic, structural, and spectroscopic studies of sterically crowded tin-chalcogen acenaphthenes

The work in this project was supported by the Engineering and Physical Sciences Research Council (EPSRC) and EaStCHEM.A series of sterically encumbered peri-substituted acenaphthenes have been prepared containing chalcogen and tin moieties at the close 5,6-positions (Acenap[SnPh3][ER], Acenap = acenaphthene-5,6-diyl, ER = SPh (1), SePh (2), TePh (3), SEt (4); Acenap[SnPh2Cl][EPh], E = S (5), Se (6); Acenap[SnBu2Cl][ER], ER = SPh(7), SePh (8), SEt (9)). Two geminally bis(peri-substituted) derivatives ({Acenap[SPh2]}2SnX2, X = Cl (10), Ph (11)) have also been prepared, along with the bromo–sulfur derivative Acenap(Br)(SEt) (15). All 11 chalcogen–tin compounds align a Sn–CPh/Sn–Cl bond along the mean acenaphthene plane and position a chalcogen lone pair in close proximity to the electropositive tin center, promoting the formation of a weakly attractive intramolecular donor–acceptor E···Sn–CPh/E···Sn–Cl 3c-4e type interaction. The extent of E→Sn bonding was investigated by X-ray crystallography and solution-state NMR and was found to be more prevalent in triorganotin chlorides 5–9 in comparison with triphenyltin derivatives 1–4. The increased Lewis acidity of the tin center resulting from coordination of a highly electronegative chlorine atom was found to greatly enhance the lp(E)−σ*(Sn–Y) donor–acceptor 3c-4e type interaction, with substantially shorter E–Sn peri distances observed in the solid state for triorganotin chlorides 5–9 (∼75% ∑rvdW) and significant 1J(119Sn,77Se) spin–spin coupling constants (SSCCs) observed for 6 (163 Hz) and 8 (143 Hz) in comparison to that for the triphenyltin derivative 2 (68 Hz). Similar observations were observed for geminally bis(peri-substituted) derivatives 10 and 11.PostprintPeer reviewe

Naphthalene and Related Systems peri-Substituted by Group 15 and 16 Elements

Synthetic and bonding aspects of heavier Group 15 (P, As, Sb, Bi) and 16 (S, Se, Te) peri-substituted naphthalenes, are discussed in this review. An important and unifying feature of the chemistry of these systems is the lively discussion about the nature of the interaction between peri-atoms. Are atoms bonded when they are closer than the sum of their van der Waals radii? Is there any (weak) bonding, or just a strained repulsive interaction? Positioning atoms of Group 15 and 16 at the naphthalene 1,8-positions provides leading systems with which to study these bonding issues.</p