29 research outputs found

    DRIFT : a numerical simulation solution for cooling tower drift eliminator performance

    Get PDF
    Topical report for Task #3 of the Waste Heat Management Research ProgramA method for the analysis of the performance of standard industrial evaporative cooling tower drift eliminators using numerical simulation methods is reported. The simulation methods make use of the computer code SOLASUR as a subroutine of the computer code DRIFT to calculate the two dimensional laminar flow velocity field and pressure loss in a drift eliminator geometry. This information is then used in the main program to obtain the eliminator collection efficiency by performing trajectory calculations for droplet's of a given size by a fourth' order Runge-Kutta numerical method.New England Electric System & Northeast Utilities Service Co

    Comparative evaluation of cooling tower drift eliminator performance

    Get PDF
    Originally presented as the author's thesis, (Ph.D.) in the M.I.T. Dept. of Nuclear Engineering, 1977.The performance of standard industrial evaporative cooling tower drift eliminators is analyzed using experiments and numerical simulations. The experiments measure the droplet size spectra at the inlet and outlet of the eliminator with a laser light scattering technique. From these measured spectra, the collection efficiency is deduced as a function of droplet size. The numerical simulations use the computer code SOLASUR as a subroutine of the computer code DRIFT to calculate the two-dimensional laminar flow velocity field and pressure drop in a drift eliminator. The SOLASUR subroutine sets up either no-slip or freeslip boundary conditions at the rigid eliminator boundaries. This flow field is used by the main program to calculate the eliminator collection efficiency by performing trajectory calculations for droplets of a given size with a fourth-order Runge-Kutta Numerical method. The experimental results are in good agreement with the collection efficiencies calculated with no-slip boundary conditions. The pressure drop data for the eliminators is measured with an electronic manometer. There is good agreement between the measured and calculated pressure losses. The results show that both particle collection efficiency and pressure loss increase as the eliminator geometry becomes more complex, and as the flowrate through the eliminator increases.New England Electric System Northeast Utilities Service Co. under the MIT Energy Laboratory Electric Power Progra

    Progress report no. 5

    Get PDF
    Includes bibliographical referencesProgress report; June 30, 1974U.S. Atomic Energy Commission contract AT(11-1)225

    2012 ACCF/AHA/ACP/AATS/PCNA/SCAI/STS guideline for the diagnosis and management of patients with stable ischemic heart disease

    Get PDF
    The recommendations listed in this document are, whenever possible, evidence based. An extensive evidence review was conducted as the document was compiled through December 2008. Repeated literature searches were performed by the guideline development staff and writing committee members as new issues were considered. New clinical trials published in peer-reviewed journals and articles through December 2011 were also reviewed and incorporated when relevant. Furthermore, because of the extended development time period for this guideline, peer review comments indicated that the sections focused on imaging technologies required additional updating, which occurred during 2011. Therefore, the evidence review for the imaging sections includes published literature through December 2011

    Epigenetic Silencing of Cellular Retinol-Binding Proteins in Nasopharyngeal Carcinoma

    Get PDF
    Aberrant retinoid signaling in human cancers is extending from the nucleus to the cytoplasm. Recently, we have demonstrated frequent epigenetic inactivation of a retinoic acid receptor (RAR), RARβ2, in nasopharyngeal carcinoma (NPC). To further explore targets contributing to aberrant retinoid signaling in NPC, the expression of cellular retinol-binding proteins (CRBPs), cellular retinoic acid-binding proteins (CRABPs), RARs, and retinoid X receptors (RXRs) was examined. Apart from RARβ2, transcriptional silencing of two CRBPs, CRBPI and CRBPIV, was observed in NPC cell lines and xenografts. Hypermethylation of CRBPI and CRBPIV CpG islands was found to be closely correlated with the loss of expression. Treatment with the DNA methyltransferase inhibitor, 5-aza2'-deoxycytidine, resulted in reexpression of CRBPI and CRBPIV gene expression in NPC cell lines. Both CRBPI and CRBPIV hypermethylations were also observed in 43/48 (87.8%) and 26/48 (54.2%) primary NPC tumors, respectively. Here, we reported for the first time that CRBPIV was transcriptionally inactivated by promoter hypermethylation in human cancer. Simultaneous methylation of CRBPI, CRBPIV, and RARβ2 was commonly found in NPC primary tumors. Our findings implied that epigenetic disruption of the CRBPs, CRBPI and CRBPIV, is important in NPC tumorigenesis and may contribute to the loss of retinoic acid responsiveness in cancer

    Short-Form Thymic Stromal Lymphopoietin (sfTSLP) Is the Predominant Isoform Expressed by Gynaecologic Cancers and Promotes Tumour Growth

    No full text
    Thymic stromal lymphopoietin (TSLP) is an epithelial cell derived cytokine belonging to the IL-7 family and a key initiator of allergic inflammation. Two main isoforms of TSLP, classified as long- (lfTSLP) and short-form (sfTSLP), have been reported in human, but their expression patterns and role(s) in cancers are not yet clear. mRNA expression was examined by isoform-specific RT-PCR and RNA in situ hybridisation. Epigenetic regulation was investigated by chromatin immunoprecipitation-PCR and bisulfite sequencing. Tumour progression was investigated by gene overexpression, cell viability assay, cancer organoid culture and transwell invasion. Signals were investigated by proteome profiler protein array and RNA-sequencing. With the use of isoform-specific primers and probes, we uncovered that only sfTSLP was expressed in the cell lines and tumour tissues of human ovarian and endometrial cancers. We also showed the epigenetic regulation of sfTSLP: sfTSLP transcription was regulated by histone acetylation at promoters in ovarian cancer cells, whereas silencing of the sfTSLP transcripts was regulated by promoter DNA methylation in endometrial cancer cells. In vitro study showed that ectopically overexpressing sfTSLP promoted tumour growth but not invasion. Human phosphokinase array application demonstrated that the sfTSLP overexpression activated phosphorylation of multiple intracellular kinases (including GSK3α/β, AMPKα1, p53, AKT1/2, ERK1/2 and Src) in ovarian cancer cells in a context-dependent manner. We further investigated the impact of sfTSLP overexpression on transcriptome by RNA-sequencing and found that EFNB2 and PBX1 were downregulated in ovarian and endometrial cancer cells, suggesting their role in sfTSLP-mediated tumour growth. In conclusion, sfTSLP is predominantly expressed in ovarian and endometrial cancers and promotes tumour growth

    Metastasis-suppressing NID2, an epigenetically-silenced gene, in the pathogenesis of nasopharyngeal carcinoma and esophageal squamous cell carcinoma

    Get PDF
    Nidogen-2 (NID2) is a key component of the basement membrane that stabilizes the extracellular matrix (ECM) network. The aim of the study is to analyze the functional roles of NID2 in the pathogenesis of nasopharyngeal carcinoma (NPC) and esophageal squamous cell carcinoma (ESCC). We performed genome-wide methylation profiling of NPC and ESCC and validated our findings using the methylation-sensitive high-resolution melting (MS-HRM) assay. Results showed that promoter methylation of NID2 was significantly higher in NPC and ESCC samples than in their adjacent non-cancer counterparts. Consistently, down-regulation of NID2 was observed in the clinical samples and cell lines of both NPC and ESCC. Re-expression of NID2 suppresses clonogenic survival and migration abilities of transduced NPC and ESCC cells. We showed that NID2 significantly inhibits liver metastasis. Mechanistic studies of signaling pathways also confirm that NID2 suppresses the EGFR/Akt and integrin/FAK/PLCγ metastasis-related pathways. This study provides novel insights into the crucial tumor metastasis suppression roles of NID2 in cancers
    corecore