186 research outputs found

    RDD-Eclat: Approaches to Parallelize Eclat Algorithm on Spark RDD Framework

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    Initially, a number of frequent itemset mining (FIM) algorithms have been designed on the Hadoop MapReduce, a distributed big data processing framework. But, due to heavy disk I/O, MapReduce is found to be inefficient for such highly iterative algorithms. Therefore, Spark, a more efficient distributed data processing framework, has been developed with in-memory computation and resilient distributed dataset (RDD) features to support the iterative algorithms. On the Spark RDD framework, Apriori and FP-Growth based FIM algorithms have been designed, but Eclat-based algorithm has not been explored yet. In this paper, RDD-Eclat, a parallel Eclat algorithm on the Spark RDD framework is proposed with its five variants. The proposed algorithms are evaluated on the various benchmark datasets, which shows that RDD-Eclat outperforms the Spark-based Apriori by many times. Also, the experimental results show the scalability of the proposed algorithms on increasing the number of cores and size of the dataset.Comment: 16 pages, 6 figures, ICCNCT 201

    Dynamical tunneling in molecules: Quantum routes to energy flow

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    Dynamical tunneling, introduced in the molecular context, is more than two decades old and refers to phenomena that are classically forbidden but allowed by quantum mechanics. On the other hand the phenomenon of intramolecular vibrational energy redistribution (IVR) has occupied a central place in the field of chemical physics for a much longer period of time. Although the two phenomena seem to be unrelated several studies indicate that dynamical tunneling, in terms of its mechanism and timescales, can have important implications for IVR. Examples include the observation of local mode doublets, clustering of rotational energy levels, and extremely narrow vibrational features in high resolution molecular spectra. Both the phenomena are strongly influenced by the nature of the underlying classical phase space. This work reviews the current state of understanding of dynamical tunneling from the phase space perspective and the consequences for intramolecular vibrational energy flow in polyatomic molecules.Comment: 37 pages and 23 figures (low resolution); Int. Rev. Phys. Chem. (Review to appear in Oct. 2007

    Regulation of Transforming Growth Factor-β1–driven Lung Fibrosis by Galectin-3

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    Rationale: Idiopathic pulmonary fibrosis (IPF) is a chronic dysregulated response to alveolar epithelial injury with differentiation of epithelial cells and fibroblasts into matrix-secreting myofibroblasts resulting in lung scaring. The prognosis is poor and there are no effective therapies or reliable biomarkers. Galectin-3 is a beta-galactoside binding lectin that is highly expressed in fibrotic tissue of diverse etiologies. Objectives: To examine the role of galectin-3 in pulmonary fibrosis. Methods: We used genetic deletion and pharmacologic inhibition in well-characterized murine models of lung fibrosis. Further mechanistic studies were performed in vitro and on samples from patients with IPF. Measurements and Main Results: Transforming growth factor (TGF)-beta and bleomycin-induced lung fibrosis was dramatically reduced in mice deficient in galectin-3, manifest by reduced TGF-beta 1 induced EMT and myofibroblast activation and collagen production. Galectin-3 reduced phosphorylation and nuclear translocation of beta-catenin but had no effect on Smad2/3 phosphorylation. A novel inhibitor of galectin -3, TD139, blocked TGF-beta-induced beta-catenin activation in vitro and in vivo and attenuated the late-stage progression of lung fibrosis after bleomycin. There was increased expression of galectin-3 in the bronchoalveolar lavage fluid and serum from patients with stable IPF compared with nonspecific interstitial pneumonitis and controls, which rose sharply during an acute exacerbation suggesting that. galectin-3 may be a marker of active fibrosis in IPF and that strategies that block galectin-3 may be effective in treating acute fibrotic exacerbations of IPF. Conclusions: This study identifies galectin-3 as an important regulator of lung fibrosis and provides a proof of principle for galectin-3 inhibition as a potential novel therapeutic strategy for IPF

    Biomarkers for Clinical and Incipient Tuberculosis: Performance in a TB-Endemic Country

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    Simple biomarkers are required to identify TB in both HIV(-)TB(+) and HIV(+)TB(+) patients. Earlier studies have identified the M. tuberculosis Malate Synthase (MS) and MPT51 as immunodominant antigens in TB patients. One goal of these investigations was to evaluate the sensitivity and specificity of anti-MS and -MPT51 antibodies as biomarkers for TB in HIV(-)TB(+) and HIV(+)TB(+) patients from a TB-endemic setting. Earlier studies also demonstrated the presence of these biomarkers during incipient subclinical TB. If these biomarkers correlate with incipient TB, their prevalence should be higher in asymptomatic HIV(+) subjects who are at a high-risk for TB. The second goal was to compare the prevalence of these biomarkers in asymptomatic, CD4(+) T cell-matched HIV(+)TB(-) subjects from India who are at high-risk for TB with similar subjects from US who are at low-risk for TB.Anti-MS and -MPT51 antibodies were assessed in sera from 480 subjects including PPD(+) or PPD(-) healthy subjects, healthy community members, and HIV(-)TB(+) and HIV(+)TB(+) patients from India. Results demonstrate high sensitivity (approximately 80%) of detection of smear-positive HIV(-)TB(+) and HIV(+)TB(+) patients, and high specificity (>97%) with PPD(+) subjects and endemic controls. While approximately 45% of the asymptomatic HIV(+)TB(-) patients at high-risk for TB tested biomarker-positive, >97% of the HIV(+)TB(-) subjects at low risk for TB tested negative. Although the current studies are hampered by lack of knowledge of the outcome, these results provide strong support for the potential of these biomarkers to detect incipient, subclinical TB in HIV(+) subjects.These biomarkers provide high sensitivity and specificity for TB diagnosis in a TB endemic setting. Their performance is not compromised by concurrent HIV infection, site of TB and absence of pulmonary manifestations in HIV(+)TB(+) patients. Results also demonstrate the potential of these biomarkers for identifying incipient subclinical TB in HIV(+)TB(-) subjects at high-risk for TB

    Effect of Body Mass Index on work related musculoskeletal discomfort and occupational stress of computer workers in a developed ergonomic setup

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    <p>Abstract</p> <p>Background</p> <p>Work urgency, accuracy and demands compel the computer professionals to spend longer hours before computers without giving importance to their health, especially body weight. Increase of body weight leads to improper Body Mass Index (BMI) may aggravate work related musculoskeletal discomfort and occupational-psychosocial stress. The objective of the study was to find out the effect of BMI on work related musculoskeletal discomforts and occupational stress of computer workers in a developed ergonomic setup.</p> <p>Methods</p> <p>A descriptive inferential study has been taken to analyze the effect of BMI on work related musculoskeletal discomfort and occupational-psychosocial stress. A total of 100 computer workers, aged 25-35 years randomly selected on convenience from software and BPO companies in Bangalore city, India for the participation in this study. BMI was calculated by taking the ratio of the subject's height (in meter) and weight (in kilogram). Work related musculoskeletal discomfort and occupational stress of the subjects was assessed by Cornell University's musculoskeletal discomfort questionnaire (CMDQ) and occupational stress index (OSI) respectively as well as a relationship was checked with their BMI.</p> <p>Results</p> <p>A significant association (p < 0.001) was seen among high BMI subjects with their increase scores of musculoskeletal discomfort and occupational stress.</p> <p>Conclusion</p> <p>From this study, it has been concluded that, there is a significant effect of BMI in increasing of work related musculoskeletal discomfort and occupational-psychosocial stress among computer workers in a developed ergonomic setup.</p

    Galanin and galanin receptor expression in neuroblastic tumours: correlation with their differentiation status

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    Neuroblastoma and its benign differentiated counterpart, ganglioneuroma, are paediatric neuroblastic tumours arising in the sympathetic nervous system. Their broad spectrum of clinical virulence is mainly related to heterogeneous biologic background and tumour differentiation. Neuroblastic tumours synthesize various neuropeptides acting as neuromodulators. Previous studies suggested that galanin plays a role in sympathetic tissue where it could be involved in differentiation and development. We investigated the expression and distribution of galanin and its three known receptors (Gal-R1, Gal-R2, Gal-R3) in 19 samples of neuroblastic tumours tissue by immunohistochemistry, in situ hybridization and fluorescent-ligand binding. This study provides clear evidence for galanin and galanin receptor expression in human neuroblastic tumours. The messengers coding for galanin, Gal-R1 and -R3 were highly expressed in neuroblastoma and their amount dramatically decreased in ganglioneuroma. In contrast, Gal-R2 levels remained unchanged. Double labelling studies showed that galanin was mainly co-expressed with its receptors whatever the differentiation stage. In neuroblastic tumours, galanin might promote cell-survival or counteract neuronal differentiation through the different signalling pathways mediated by galanin receptors. Finally, our results suggest that galanin influences neuroblastoma growth and development as an autocrine/paracrine modulator. These findings suggest potential critical implications for galanin in neuroblastic tumours development

    Induction of the interleukin 6/ signal transducer and activator of transcription pathway in the lungs of mice sub-chronically exposed to mainstream tobacco smoke

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    <p>Abstract</p> <p>Background</p> <p>Tobacco smoking is associated with lung cancer and other respiratory diseases. However, little is known about the global molecular changes that precede the appearance of clinically detectable symptoms. In this study, the effects of mainstream tobacco smoke (MTS) on global transcription in the mouse lung were investigated.</p> <p>Methods</p> <p>Male C57B1/CBA mice were exposed to MTS from two cigarettes daily, 5 days/week for 6 or 12 weeks. Mice were sacrificed immediately, or 6 weeks following the last cigarette. High density DNA microarrays were used to characterize global gene expression changes in whole lung. Microarray results were validated by Quantitative real-time RT-PCR. Further analysis of protein synthesis and function was carried out for a select set of genes by ELISA and Western blotting.</p> <p>Results</p> <p>Globally, seventy nine genes were significantly differentially expressed following the exposure to MTS. These genes were associated with a number of biological processes including xenobiotic metabolism, redox balance, oxidative stress and inflammation. There was no differential gene expression in mice exposed to smoke and sampled 6 weeks following the last cigarette. Moreover, cluster analysis demonstrated that these samples clustered alongside their respective controls. We observed simultaneous up-regulation of <it>interleukin 6 </it>(<it>IL-6</it>) and its antagonist, <it>suppressor of cytokine signalling </it>(<it>SOCS3</it>) mRNA following 12 weeks of MTS exposure. Analysis by ELISA and Western blotting revealed a concomitant increase in total IL-6 antigen levels and its downstream targets, including phosphorylated signal transducer and activator of transcription 3 (Stat3), basal cell-lymphoma extra large (BCL-XL) and myeloid cell leukemia 1 (MCL-1) protein, in total lung tissue extracts. However, in contrast to gene expression, a subtle decrease in total SOCS3 protein was observed after 12 weeks of MTS exposure.</p> <p>Conclusion</p> <p>Global transcriptional analysis identified a set of genes responding to MTS exposure in mouse lung. These genes returned to basal levels following smoking cessation, providing evidence to support the benefits of smoking cessation. Detailed analyses were undertaken for IL-6 and its associated pathways. Our results provide further insight into the role of these pathways in lung injury and inflammation induced by MTS.</p
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