Time filter

Source Type

Jindal V.,Apeejay Stya University | Bawa S.,Thapar University | Batra S.,Thapar University
Information Processing and Management | Year: 2014

With ever increasing information being available to the end users, search engines have become the most powerful tools for obtaining useful information scattered on the Web. However, it is very common that even most renowned search engines return result sets with not so useful pages to the user. Research on semantic search aims to improve traditional information search and retrieval methods where the basic relevance criteria rely primarily on the presence of query keywords within the returned pages. This work is an attempt to explore different relevancy ranking approaches based on semantics which are considered appropriate for the retrieval of relevant information. In this paper, various pilot projects and their corresponding outcomes have been investigated based on methodologies adopted and their most distinctive characteristics towards ranking. An overview of selected approaches and their comparison by means of the classification criteria has been presented. With the help of this comparison, some common concepts and outstanding features have been identified. © 2013 Elsevier Ltd. All rights reserved. Source

Dhingra V.,Apeejay Stya University | Bhatia K.,YMCA University of Science and Technology
International Journal of Information Technology and Web Engineering | Year: 2012

Ontologies are the backbone of knowledge representation on Semantic web. Challenges involved in building ontologies are in terms of time, efforts, skill, and domain specific knowledge. In order to minimize these challenges, one of the major advantages of ontologies is its potential of "reuse," currently supported by various search engines like Swoogle, Ontokhoj. As the number of ontologies that such search engines like Swoogle, OntoKhoj Falcon can find increases, so will the need increase for a proper ranking method to order the returned lists of ontologies in terms of their relevancy to the query which can save a lot of time and effort. This paper deals with analysis of various ontology ranking algorithms. Based on the analysis of different ontology ranking algorithms, a comparative study is done to find out their relative strengths and limitations based on various parameters which provide a significant research direction in ranking of ontologies in semantic web. Copyright © 2012, IGI Global. Source

Yadav A.K.,National Institute of Nutrition | Tyagi A.,National Dairy Research Institute | Kumar A.,Seth jai parkash mukand lal institute of engineering and technology | Saklani A.C.,Apeejay Stya University | And 2 more authors.
Archives of Microbiology | Year: 2014

Adhesion to the human intestinal epithelial cell is considered as one of the important selection criteria of lactobacilli for probiotic attributes. Sixteen Lactobacillus plantarum strains from human origins were subjected for adhesion to extracellular matrix (ECM) components, and their physiochemical characterization, incubation time course and effect of different pH on bacterial adhesion in vitro were studied. Four strains showed significant binding to both fibronectin and mucin. After pretreatment with pepsin and trypsin, the bacterial adhesion to ECM reduced to the level of 50 % and with lysozyme significantly decreased by 65–70 %. Treatment with LiCl also strongly inhibited (90 %) the bacterial adhesion to ECM. Tested strains showed highest binding efficacy at time course of 120 and 180 min. Additionally, the binding of Lp91 to ECM was highest at pH 6 (155 ± 2.90 CFU/well). This study proved that surface layer components are proteinaceous in nature, which contributed in adhesion of lactobacillus strains. Further, the study can provide a better platform for introduction of new indigenous probiotic strains having strong adhesion potential for future use. © 2014, Springer-Verlag Berlin Heidelberg. Source

Kumar A.,Apeejay Stya University
E-Journal of Chemistry | Year: 2011

The triplex formation of disulphide containing oligonucleotide with duplex DNA using melting temperature studies is reported. The stability of the triplex formed with disulphide containing oligonucleotide was compared with unmodified oligonucleotide and C-5 propyne deoxyuridine containing oligonucleotide. Melting temperature (Tm) values of the triplexes formed with disulphide containing oligonucleotide were found to be 37 oC and 46 oC at pH 7 and 6 respectively. The triplexes formed with C-5 propyne deoxyuridine substituted oligonucleotide showed Tm values at 27 oC and 42 oC at pH 7 and 6. The Tm values of the triplexes formed with unmodified oligonucleotide were found to be 18 oC and 32 oC at pH 7 and 6 respectively. This clearly demonstrates that disulphide containing oligonucleotide stabilzes triplex DNA structure better than unmodified oligonucleotide as well as C-5 propyne deoxyuridine containing oligonucleotide when targeted with duplex DNA at both the mentioned pH values. Source

Kumar A.,Apeejay Stya University
E-Journal of Chemistry | Year: 2011

The small dumbbell oligonucleotides containing loops of phosphodiester (OL-1), two trimethylene, C3 moieties in each loop (OL-2) and phosphorothioate (OL-3) linkages were synthesized. Incubation of OL-1 and OL-2 with S-1 nuclease generated break down products whereas incubation of OL-3 did not result in significant cleavage. Their binding to moloney murine leukemia virus reverse transcriptase was evaluated by PAGE band mobility shift assays. The OL-3 bound more strongly to the reverse transcriptase than OL-1 and OL-2. The dissociation constants evaluated using PAGE band mobility shift assays were of the order of 10-7. Investigation of inhibition of RNase H activity of reverse transcriptase showed that the OL-3 is a better inhibitor of the retroviral RNase H activity than both OL-1 and OL-2. Thus OL- 3 may be used as RNase H inhibitor. Our studies demonstrated that this particularly designed oligonucleotide (OL-3) displays an IC50 of 25 nM in its inhibition on the reverse transcriptase RNase H activity, a magnitude lower than that of first nucleotide reverse transcriptase of HIV-1, tenofovir, introduced by Gilead Science in the market. Source

Discover hidden collaborations