A novel face recognition system using hybrid neural and dual eigenspaces methods

2002-2003 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Shear capacity evaluation of reinforced concrete beams: finite element simulation

The shear performance of reinforced concrete beams with rectangle cross-section and two different continuous rectangular spiral shear reinforcement under monotonous loading is numerically evaluated. Further, the behaviour of two continuous shear reinforcement systems named, “Single Square Spring Shear Resistance System” (SSSSRS) and “Double Square Spring Shear Resistance System” (DSSSRS) as transverse reinforcements are compared with conventional discontinuous system “Stirrups”. The finite element study includes three (3) beams. The results clearly show that the application of continuous shear reinforcement system delivered improved shear behaviour and enhanced bearing capacity in beams. Beams with Single Square Spring Shear Resistance System (SSSSRS) and Double Square Spring Shear Resistance System (DSSSRS) exhibited 14.4% and 19.8% increased shear performance in comparison with conventional control beam. It was concluded that under the same deflection higher forces was achieved for “Single Square Spring Shear Resistance System” (SSSSRS) and “Double Square Spring Shear Resistance System” (DSSSRS) compared to control specimens

Emotional persistence in online chatting communities

How do users behave in online chatrooms, where they instantaneously read and write posts? We analyzed about 2.5 million posts covering various topics in Internet relay channels, and found that user activity patterns follow known power-law and stretched exponential distributions, indicating that online chat activity is not different from other forms of communication. Analysing the emotional expressions (positive, negative, neutral) of users, we revealed a remarkable persistence both for individual users and channels. I.e. despite their anonymity, users tend to follow social norms in repeated interactions in online chats, which results in a specific emotional "tone" of the channels. We provide an agent-based model of emotional interaction, which recovers qualitatively both the activity patterns in chatrooms and the emotional persistence of users and channels. While our assumptions about agent's emotional expressions are rooted in psychology, the model allows to test different hypothesis regarding their emotional impact in online communication.Comment: 34 pages, 4 main and 12 supplementary figure

Aharonov-Bohm interference in topological insulator nanoribbons

Topological insulators represent novel phases of quantum matter with an insulating bulk gap and gapless edges or surface states. The two-dimensional topological insulator phase was predicted in HgTe quantum wells and confirmed by transport measurements. Recently, Bi2Se3 and related materials have been proposed as three-dimensional topological insulators with a single Dirac cone on the surface and verified by angle-resolved photoemission spectroscopy experiments. Here, we show unambiguous transport evidence of topological surface states through periodic quantum interference effects in layered single-crystalline Bi2Se3 nanoribbons. Pronounced Aharonov-Bohm oscillations in the magnetoresistance clearly demonstrate the coverage of two-dimensional electrons on the entire surface, as expected from the topological nature of the surface states. The dominance of the primary h/e oscillation and its temperature dependence demonstrate the robustness of these electronic states. Our results suggest that topological insulator nanoribbons afford novel promising materials for future spintronic devices at room temperature.Comment: 5 pages, 4 figures, RevTex forma

An incremental dual nu-support vector regression algorithm

© 2018, Springer International Publishing AG, part of Springer Nature. Support vector regression (SVR) has been a hot research topic for several years as it is an effective regression learning algorithm. Early studies on SVR mostly focus on solving large-scale problems. Nowadays, an increasing number of researchers are focusing on incremental SVR algorithms. However, these incremental SVR algorithms cannot handle uncertain data, which are very common in real life because the data in the training example must be precise. Therefore, to handle the incremental regression problem with uncertain data, an incremental dual nu-support vector regression algorithm (dual-v-SVR) is proposed. In the algorithm, a dual-v-SVR formulation is designed to handle the uncertain data at first, then we design two special adjustments to enable the dual-v-SVR model to learn incrementally: incremental adjustment and decremental adjustment. Finally, the experiment results demonstrate that the incremental dual-v-SVR algorithm is an efficient incremental algorithm which is not only capable of solving the incremental regression problem with uncertain data, it is also faster than batch or other incremental SVR algorithms

Effects of cyclooxygenase-1 and -2 gene disruption on Helicobacter pylori-induced gastric inflammation

Background. Cyclooxygenases (COXs) play important roles in inflammation and carcinogenesis. The present study aimed to determine the effects of COX-1 and COX-2 gene disruption on Helicobacter pylori-induced gastric inflammation. Methods. Wild-type (WT), COX-1 and COX-2 heterozygous (COX-1 +/- and COX-2 +/-), and homozygous COX-deficient (COX-1 -/- and COX-2 -/-) mice were inoculated with H. pylori strain TN2 and killed after 24 weeks of infection. Uninfected WT and COX-deficient mice were used as controls. Levels of gastric mucosal inflammation, epithelial cell proliferation and apoptosis, and cytokine expression were determined. Results. COX deficiency facilitated H. pylori-induced gastritis. In the presence of H. pylori infection, apoptosis was increased in both WT and COX-deficient mice, whereas cell proliferation was increased in WT and COX-1-deficient, but not in COX-2-deficient, mice. Tumor necrosis factor (TNF)-α and interleukin-10 mRNA expression was elevated in H. pylori-infected mice, but only TNF-α mRNA expression was further increased by COX deficiency. Prostaglandin E 2 levels were increased in infected WT and COX-2-deficient mice but were at very low levels in infected COX-1-deficient mice. Leukotriene (LT) B 4 and LTC 4 levels were increased to a similar extent in infected WT and COX-deficient mice. Conclusions. COX deficiency enhances H. pylori-induced gastritis, probably via TNF-α expression. COX-2, but not COX-1, deficiency suppresses H. pylori-induced cell proliferation. © 2006 by the Infectious Diseases Society of America. All rights reserved.published_or_final_versio

Back reaction, covariant anomaly and effective action

In the presence of back reaction, we first produce the one-loop corrections for the event horizon and Hawking temperature of the Reissner-Nordstr\"om black hole. Then, based on the covariant anomaly cancelation method and the effective action technique, the modified expressions for the fluxes of gauge current and energy momentum tensor, due to the effect of back reaction, are obtained. The results are consistent with the Hawking fluxes of a (1+1)-dimensional blackbody at the temperature with quantum corrections, thus confirming the robustness of the covariant anomaly cancelation method and the effective action technique for black holes with back reaction.Comment: 17 page

Genetical genomics: spotlight on QTL hotspots

No abstract available

Anticancer Gene Transfer for Cancer Gene Therapy

Gene therapy vectors are among the treatments currently used to treat malignant tumors. Gene therapy vectors use a specific therapeutic transgene that causes death in cancer cells. In early attempts at gene therapy, therapeutic transgenes were driven by non-specific vectors which induced toxicity to normal cells in addition to the cancer cells. Recently, novel cancer specific viral vectors have been developed that target cancer cells leaving normal cells unharmed. Here we review such cancer specific gene therapy systems currently used in the treatment of cancer and discuss the major challenges and future directions in this field

Genomic-Bioinformatic Analysis of Transcripts Enriched in the Third-Stage Larva of the Parasitic Nematode Ascaris suum

Differential transcription in Ascaris suum was investigated using a genomic-bioinformatic approach. A cDNA archive enriched for molecules in the infective third-stage larva (L3) of A. suum was constructed by suppressive-subtractive hybridization (SSH), and a subset of cDNAs from 3075 clones subjected to microarray analysis using cDNA probes derived from RNA from different developmental stages of A. suum. The cDNAs (n = 498) shown by microarray analysis to be enriched in the L3 were sequenced and subjected to bioinformatic analyses using a semi-automated pipeline (ESTExplorer). Using gene ontology (GO), 235 of these molecules were assigned to ‘biological process’ (n = 68), ‘cellular component’ (n = 50), or ‘molecular function’ (n = 117). Of the 91 clusters assembled, 56 molecules (61.5%) had homologues/orthologues in the free-living nematodes Caenorhabditis elegans and C. briggsae and/or other organisms, whereas 35 (38.5%) had no significant similarity to any sequences available in current gene databases. Transcripts encoding protein kinases, protein phosphatases (and their precursors), and enolases were abundantly represented in the L3 of A. suum, as were molecules involved in cellular processes, such as ubiquitination and proteasome function, gene transcription, protein–protein interactions, and function. In silico analyses inferred the C. elegans orthologues/homologues (n = 50) to be involved in apoptosis and insulin signaling (2%), ATP synthesis (2%), carbon metabolism (6%), fatty acid biosynthesis (2%), gap junction (2%), glucose metabolism (6%), or porphyrin metabolism (2%), although 34 (68%) of them could not be mapped to a specific metabolic pathway. Small numbers of these 50 molecules were predicted to be secreted (10%), anchored (2%), and/or transmembrane (12%) proteins. Functionally, 17 (34%) of them were predicted to be associated with (non-wild-type) RNAi phenotypes in C. elegans, the majority being embryonic lethality (Emb) (13 types; 58.8%), larval arrest (Lva) (23.5%) and larval lethality (Lvl) (47%). A genetic interaction network was predicted for these 17 C. elegans orthologues, revealing highly significant interactions for nine molecules associated with embryonic and larval development (66.9%), information storage and processing (5.1%), cellular processing and signaling (15.2%), metabolism (6.1%), and unknown function (6.7%). The potential roles of these molecules in development are discussed in relation to the known roles of their homologues/orthologues in C. elegans and some other nematodes. The results of the present study provide a basis for future functional genomic studies to elucidate molecular aspects governing larval developmental processes in A. suum and/or the transition to parasitism