Existence of Nearest Neighbor and Variable Range Hopping in Pr2_2ZnMnO6_6

A joint investigation of X-ray diffraction (XRD) pattern and Raman spectrum authenticate the double phase monoclinic P21/n and cubic Fd-3m structures of polycrystalline Pr2ZnMnO6 (PZM). The existence of two different conduction mechanisms (Nearest neighbor hopping and Motts variable range hopping) is observed using a combined study of conductivity, dielectric relaxation and impedance spectra in PZM. This investigation point towards a transition from nearest neighbor hoping to Motts variable range hopping mechanism due to lowering activation energy around 580 K. The charge carriers hopping between the localized acceptor states at the grain boundaries (GBs), which dominants conduction mechanism below 580 K. The ac conductivity, dielectric relaxation, Nyquist plot, and electric modulus highlight the blended effect of grains (Gs) and GBs leads to the charge carrier dynamics in PZM. The dielectric relaxation and modulus formalism are analyzed on the basis of empirical Cole-Cole model. The conduction mechanism is found to be highly correlated with the relaxation mechanism and impedance spectroscopy.Comment: 15 page

Close Range High Voltage Multiplier Device

This project has been implemented to create a sample, cheap and easy to make “Electroshock defensive device†.This is powered from a 9 volt DC source making use of basic electronic components. This voltage is multiplied through the Cockroft –Walton Voltage Multiplier Ladder.It generates a high voltage arc across its output electrodes ranging from 4.5KV to 75000KV.The output voltage is pulsating. Based on the prototype design this can be used for a plethora of applications. This must be handled with extreme precaution since misuse of device may lead to hazardous accidents

Special Issue on Survivable and Resilient Communication Networks and Services

Communication networks and services play a vital role in our modern lives. This importance is expected to continue to grow in future decades. More and more business, healthcare or government organizations will become increasingly dependent on the communication between their offices and people. Not only does modern society depend on these services in terms of availability but also in terms of proper functioning in all circumstances. These services having stringent requirements with respect to protection of privacy and security. Anonymity (such as e-health) cannot accept, for example, temporary leakage of confidential information by accident whether a result of human error or technical problems. The information and communication network technology itself have also been evolving with tremendous breakthroughs. Users have more and more different types of mobile devices that interconnect them to the Internet. These mobile devices provide incentives to generate novel technology paradigms that enable more flexible provisioning, network virtualization, or improved power efficiency. The robustness and fault tolerance of these novel evolutions is as crucial as ever

A Study on Traumatic Faciomaxillary Fractures Encountered at a Tertiary Care Centre of North-Eastern India

Introduction Faciomaxillary fractures can present either as an isolated injury or as a part of polytrauma. The incidence of faciomaxillary injuries is on the incline with changing lifestyles in developing countries like India; thus posing as a major health burden. We conducted this study to aid in defining strategies to prevent and tackle the same. Materials and Methods A Prospective Observational study was conducted on all the patients admitted for traumatic faciomaxillary fractures in the Department of ENT for a period of three years. Aim of the study was to study the incidence, demography, pattern, management and postoperative complications in traumatic faciomaxillary fractures. Result Out of 499 cases who comprised our study group, the most common fracture encountered was of nasal bone(26.25%) with male predominance (86.37%), mostly scattered in the age group of 18-40 yrs (67.13%). RTA was found to be the most common cause (52.1%). Fractures of lateral third of face and mandible almost always needed an open reduction. Discussion The age and gender distribution pattern as well as the cause of faciomaxillary fractures and complications have been compared with the published reports. The central third of the facial skeleton has been found to be affected most in traumatic fractures, whereas some other studies found fracture of the mandible to be the most common. Open reduction was needed in 44.9% of patients.   Conclusion With increasing incidence of RTAs, there is a need to understand the pattern, review our management techniques and hence be able to provide appropriate and individualized management to those in need of it

A Unified Software Architecture to Enable Cross-Layer Design in the Future Internet

Abstract—While research on cross-layer network optimization has been progressing, useful implementations have been lagging because the current Internet architecture does not accommodate cross-layering gracefully. As part of our FIND project, we propose a software architecture for the future Internet that is designed to accommodate such interactions. We present a conceptual overview as well as high level software design and an early prototype implementation, and point out the strengths of our architecture. I

Identification and Characterization of Differentially Expressed Transcripts in the Gills of Freshwater Prawn (Macrobrachium rosenbergii) under Salt Stress

The giant freshwater prawn, Macrobrachium rosenbergii, is an economically important species. It is a euryhaline shrimp, surviving in wide-range salinity conditions. A change in gene expression has been suggested as an important component for stress management. To better understand the osmoregulatory mechanisms mediated by the gill, a subtractive and suppressive hybridization (SSH) tool was used to identify expressed transcripts linked to adaptations in saline water. A total of 117 transcripts represented potentially expressed under salinity conditions. BLAST analysis identified 22% as known genes, 9% as uncharacterized showing homologous to unannotated ESTs, and 69% as unknown sequences. All the identified known genes representing broad spectrum of biological pathways were particularly linked to stress tolerance including salinity tolerance. Expression analysis of 10 known genes and 7 unknown/uncharacterized genes suggested their upregulation in the gills of prawn exposed to saline water as compared to control indicating that these are likely to be associated with salinity acclimation. Rapid amplification of cDNA ends (RACE) was used for obtaining full-length cDNA of MRSW-40 clone that was highly upregulated during salt exposure. The sequenced ESTs presented here will have potential implications for future understanding about salinity acclimation and/or tolerance of the prawn

A Late Cretaceous amber biota from central Myanmar

International audienceInsect faunas are extremely rare near the latest Cretaceous with a 24-million-year gap spanning from the early Campanian to the early Eocene. Here, we report a unique amber biota from the Upper Cretaceous (uppermost Campanian ~72.1 Ma) of Tilin, central Myan-mar. The chemical composition of Tilin amber suggests a tree source among conifers, indicating that gymnosperms were still abundant in the latest Campanian equatorial forests. Eight orders and 12 families of insects have been found in Tilin amber so far, making it the latest known diverse insect assemblage in the Mesozoic. The presence of ants of the extant sub-families Dolichoderinae and Ponerinae supports that tropical forests were the cradle for the diversification of crown-group ants, and suggests that the turnover from stem groups to crown groups had already begun at ~72.1 Ma. Tilin amber biota fills a critical insect faunal gap and provides a rare insight into the latest Campanian forest ecosystem

Designing for Network and Service Continuity in Wireless Mesh Networks

“Designing for Network and Service Continuity in Wireless Mesh Networks” describes performance predictability of the new wireless mesh network paradigm, and describes considerations in designing networks from the perspective of survivability and service continuity metrics.  The work provides design insights for network design researchers and industry professionals. It includes designs for new mesh networks and extensions of existing networks with predictable performance

On Optimal Traffic Grooming in WDM Rings

We consider the problem of designing a virtual topology to minimize electronic routing, that is, grooming traffic, in wavelength routed optical rings. The full virtual topology design problem is NP-hard even in the restricted case where the physical topology is a ring, and various heuristics have been proposed in the literature for obtaining good solutions, usually for different classes of problem instances. We present a new framework which can be used to evaluate the performance of heuristics and which requires significantly less computation than evaluating the optimal solution. This framework is based on a general formulation of the virtual topology problem, and it consists of a sequence of bounds, both upper and lower, in which each successive bound is at least as strong as the previous one. The successive bounds take larger amounts of computation to evaluate, and the number of bounds to be evaluated for a given problem instance is only limited by the computational power available. The bounds are based on decomposing the ring into sets of nodes arranged in a path and adopting the locally optimal topology within each set. While we only consider the objective of minimizing electronic routing in this paper, our approach to obtaining the sequence of bounds can be applied to many virtual topology problems on rings. The upper bounds we obtain also provide a useful series of heuristic solutions