217 research outputs found

    Flexible Support Stanchion

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    Figure 1 shows the assembly drawing of the Central Calorimeter Cryostat Flexible Support Stanchion. Figures 2 and 3 show the Flexible Support STanchion in detail. These Stanchions support the cryostat safely, reduce the heat load to the cryostat from the ambient by a factor of more than ten, provide a spring like action that reduce the loads created by thermal contraction of the cryostat and position the cryostate accurately. Table 1 shows all of the details of the Flexible Support system for the C.C. Cryostat

    PVP2008-61205 NATURAL FLAW SHAPE DEVELOPMENT DUE TO STRESS CORROSION CRACKING

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    ABSTRACT Typical ASME Section XI subcritical cracking analyses assume an idealized flaw shape driven by stress intensity factors developed for semi-elliptical shaped flaws. Recent advanced finite element analyses (AFEA) conducted by both the US NRC and the nuclear industry for long circumferential indications found in the pressurizer nozzle dissimilar metal welds at the Wolf Creek power plant, suggest that the semielliptical flaw assumption may be overly conservative in some cases. The AFEA methodology that was developed allowed the progression of a planar flaw subjected to typical SCC-type growth laws by calculating stress intensity factors at every nodal point along the crack front, and incrementally advancing the crack front in a more natural manner. Typically crack growth analyses increment the semi-elliptical flaw by considering only the stress intensity factor at the deepest and surface locations along the crack front, while keeping the flaw shape semi-elliptical. In this paper, a brief background to the AFEA methodology and the analyses conducted in the Wolf Creek effort will be discussed. In addition, the natural behavior of surface cracks under normal operating conditions (plus welding residual stress) will be investigated and compared to the semi-elliptical assumption. Conclusions on the observation of when semi-elliptical flaw assumptions are appropriate will be made. These observations will add insight into the conservatism of using an idealized flaw shape assumption. INTRODUCTION In October 2006, circumferential indications were located by ultrasonic testing (UT) in three of the pressurizer nozzle dissimilar metal (DM) welds at the Wolf Creek nuclear power plant. The indications located were relatively long circumferential defects in Alloy 82/182 dissimilar metal welds. In one case the flaw was sized at 43% of the circumference and 26% deep. Using ASME Section XI type analyses, Emc 2 and NRC staff estimated the times to both leakage and rupture fo

    The effect of 14 weeks of vitamin D3 supplementation on antimicrobial peptides and proteins in athletes

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    Heavy training is associated with increased respiratory infection risk and antimicrobial proteins are important in defence against oral and respiratory tract infections. We examined the effect of 14 weeks of vitamin D3 supplementation (5000 IU/day) on the resting plasma cathelicidin concentration and the salivary secretion rates of secretory immunoglobulin A (SIgA), cathelicidin, lactoferrin and lysozyme in athletes during a winter training period. Blood and saliva were obtained at the start of the study from 39 healthy men who were randomly allocated to vitamin D3 supplement or placebo. Blood samples were also collected at the end of the study; saliva samples were collected after 7 and 14 weeks. Plasma total 25(OH)D concentration increased by 130% in the vitamin D3 group and decreased by 43% in the placebo group (both P=0.001). The percentage change of plasma cathelicidin concentration in the vitamin D3 group was higher than in the placebo group (P=0.025). Only in the vitamin D3 group, the saliva SIgA and cathelicidin secretion rates increased over time (both P=0.03). A daily 5000 IU vitamin D3 supplement has a beneficial effect in up-regulating the expression of SIgA and cathelicidin in athletes during a winter training period which could improve resistance to respiratory infections

    S100A4 Elevation Empowers Expression of Metastasis Effector Molecules in Human Breast Cancer.

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    Many human glandular cancers metastasize along nerve tracts, but the mechanisms involved are generally poorly understood. The calcium-binding protein S100A4 is expressed at elevated levels in human cancers, where it has been linked to increased invasion and metastasis. Here we report genetic studies in a Drosophila model to define S100A4 effector functions that mediate metastatic dissemination of mutant Ras-induced tumors in the developing nervous system. In flies overexpressing mutant RasVal12 and S100A4, there was a significant increase in activation of the stress kinase JNK and production of the matrix metalloproteinase MMP1. Genetic or chemical blockades of JNK and MMP1 suppressed metastatic dissemination associated with S100A4 elevation, defining required signaling pathway(s) for S100A4 in this setting. In clinical specimens of human breast cancer, elevated levels of the mammalian paralogs MMP2, MMP9, and MMP13 are associated with a 4- to 9-fold relative decrease in patient survival. In individual tumors, levels of MMP2 and MMP13 correlated more closely with levels of S100A4, whereas MMP9 levels correlated more closely with the S100 family member S100P. Overall, our results suggest the existence of evolutionarily conserved pathways used by S100A4 to promote metastatic dissemination, with potential prognostic and therapeutic implications for metastasis by cancers that preferentially exploit nerve tract migration routes. Cancer Res; 77(3); 1-10. ©2016 AACR
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