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Motivation/Background: Red complex bacteria are proven periodontal pathogens. In dentistry, there is a need to identify and quantitate the organisms from the diseased sites quickly and reliably. Since culture requires several days, molecular methods are being used frequently to detect these bacteria. Among them, Fluorescent in situ hybridization (FISH) is rapid, sensitive and quantitative. An attempt is made here to evaluate the applicability of this technique as a diagnostic tool in periodontology. Method: Subgingival plaque was collected from participants, fixed with paraformaldehyde and subjected to FISH. Fluorescently labeled oligonucleotide probes were used for hybridization. After the procedure, the fluorescently stained bacteria were identified and counted from the smear and quantitated using a simple grading. Results: There was a significant difference in the prevalence and numbers of red complex bacteria in healthy and diseased subjects. A strong linear relationship existed between P. gingivalis, T. forsythia and T. denticola. Conclusions: The procedure used in the study is simple, rapid and can be easily adaptable. It also has a high sensitivity and has the ability to detect a single bacterial cell. The method can be directly applied to the clinical samples and can be used as a rapid diagnostic tool in periodontics..

In this paper a new power efficient routing algorithm for MANETs with self-organizing and self-routing features is described and its performance analyzed in different simulation scenarios. The algorithm has the logic of a non-cooperative routing algorithm based on the evaluation of a weight parameter, the latter being a function of properties of the MANET nodes related to the nominal available power and the transmission range. A self-estimation of this weight parameter for each node is introduced in the routing process based on the status and functional history of the node. The routing is based on network layering, formation of service areas in each layer and choice of nodes from these areas to have the functionality of default gateways. The proposed algorithm, named service zone gateway prediction (SZGP), is a hybrid type of routing mechanism, incorporating pre-computed multipath hop-by-hop distributed routing, with a periodically updated hierarchical multilayered structure. The results from the simulation experiments show that the performance of the proposed SZGP algorithm in relation to the basic performance parameters such as packet delivery ratio, delay and throughput are similar to those of the well-known AODV algorithm, but in relation to power efficiency the proposed algorithm outperforms AODV significantly. This is due to the fact that such an approach reduces the overall number of broadcasts in the network and ensures a reliable and energy efficient connection by balancing the load among the nodes.

Aims and Objectives: The oral microbial flora is highly complex and diverse with obligate anaerobic bacteria as the predominant component. Most of these are not yet cultivated/difficult to cultivate due to technical limitations. In this study, we aim to detect two novel oral bacterial species Dialister invisus and Olsenella uli by simplified and economical procedure of polymerase chain reaction (PCR) and study their association with primary and persistent endodontic infections. Material and Methods: The study involved 60 patients that included 30 patients of primary endodontic infections and 30 with persistent endodontic infections. The sample collection from the root canal was performed by universally accepted protocol by using sterile paper points. The deoxyribonucleic acid (DNA) extraction was done, followed by PCR with species specific primers. We made several changes to the protocol mentioned by original authors. We adopted a one-step protocol for amplification of bacterial DNA, omitting the 16SrDNA amplification step with universal primers. Results: It was seen that 7 (23.3 %) samples in primary endodontic infection group and 24 (80 %) samples in persistent endodontic infection group were positive for D. invisus. On the other hand, 11 (36.6 %) patients of primary endodontic infection showed positivity for O. uli in comparison to 9 (30 %) of persistent endodontic infection. Conclusion: The results from the present study showed efficient amplification of both O. uli and D. invisus in a single-step PCR. Hence, we conclude that the modified protocol used here with taq polymerase enzyme offers a faster and cheaper alternative to nested PCR without compromising the quality of amplification process.

Porphyromonas gingivalis is a keystone pathogen and major colonizer in host tissue which plays a pivotal role in periodontitis among the other polymicrobial infections. Increasing facts demonstrate that curcumin has antibacterial activity and anti-biofilm effect against the periodontopathogens through diverse mechanisms that have a positive impact on periodontal health. The present study was aimed to elucidate the effect of curcumin on biofilm formation and virulence factor gene expression of P. gingivalis. By using gene expression studies, we exploited the mechanism of anti-biofilm effects of curcumin on P. gingivalis. The minimum inhibitory concentration and minimum bactericidal concentration of curcumin for both ATCC and clinical strains of P. gingivalis were found to be 62.5 and 125 µg ml

Congenital heart surgery was born in the USA and then spread all over the world in the second half of the twentieth century. The speciality was brought to India by foreign-trained Indian surgeons as well as American and Canadian missionary surgeons. The first generation Indian surgeons were trained in the USA, Canada, Australia, and New Zealand. In this article, an attempt is made to explore how the pioneer surgeons established this speciality in India by reviewing the published literature, visiting institutions of historical significance, and also interviewing few surgeons who took the key role in both laying the foundation as well as training the next generation surgeons.

This paper presents the experimental results of the path generated by a few widely accepted path planning algorithms used for stationary obstacle avoidance in UAVs. The algorithms evaluated were Dijkstra, A*, Artificial Potential Field planning, RRT, and RRT*. The evaluation parameters for these algorithms were the length of the path, maximum deviation angle, and the clearance between the path and the obstacles.

Searchable symmetric encryption (SSE) scheme allows a data owner to perform search queries over encrypted documents using symmetric cryptography. SSE schemes are useful in cloud storage and data outsourcing. Most of the SSE schemes in existing literature have been proved to leak a substantial amount of information that can lead to an inference attack. This paper presents, a novel leakage resilient searchable symmetric encryption with periodic updation (LRSSEPU) scheme that minimizes extra information leakage, and prevents an untrusted cloud server from performing document mapping attack, query recovery attack and other inference attacks. In particular, the size of the keyword vector is fixed and the keywords are periodically permuted and updated to achieve minimum leakage. Furthermore, our proposed LRSSEPU scheme provides authentication of the query messages and restricts an adversary from performing a replay attack, forged query attack and denial of service attack. We employ a combination of identity-based cryptography (IBC) with symmetric key cryptography to reduce the computation cost and communication overhead. Our scheme is lightweight and easy to implement with very little communication overhead.