Measurements of SCRF cavity dynamic heat load in horizontal test system

The Horizontal Test System (HTS) at Fermilab is currently testing fully assembled, dressed superconducting radio frequency (SCRF) cavities. These cavities are cooled in a bath of superfluid helium at 1.8K. Dissipated RF power from the cavities is a dynamic heat load on the cryogenic system. The magnitude of heat flux from these cavities into the helium is also an important variable for understanding cavity performance. Methods and hardware used to measure this dynamic heat load are presented. Results are presented from several cavity tests and testing accuracy is discussed.Comment: 6 pp. Cryogenic Engineering Conference and International Cryogenic Materials Conference 28 Jun - 2 Jul 2009. Tucson, Arizon

Fermilab SRF cryomodule operational experience

Fermi National Accelerator Laboratory is constructing an Advanced Accelerator Research and Development facility at New Muon Lab. The cryogenic infrastructure in support of the initial phase of the facility consists of two Tevatron style standalone refrigerators, cryogenic distribution system as well as an ambient temperature pumping system to achieve 2 K operations with supporting purification systems. During this phase of the project a single Type III plus 1.3 GHz cryomodule was installed, cooled and tested. Design constraints of the cryomodule required that the cryomodule individual circuits be cooled at predetermined rates. These constraints required special design solutions to achieve. This paper describes the initial cooldown and operational experience of a 1.3 GHz cryomodule using the New Muon Lab cryogenic system.Comment: 7 pp. Cryogenic Engineering Conference and International Cryogenic Materials Conference CEC-ICMC 2011 13-17 June 2011, Spokane, Washingto

Critical speed measurements in the Tevatron cold compressors

The Fermilab Tevatron cryogenic system utilizes high-speed centrifugal cold compressors, manufactured by Ishikawajima-Harima Heavy Industries Co. Ltd. (IHI), for high energy operations. Nominal operating range for these compressors is 43,000 to 85,000 rpm. Past foil bearing failures prompted investigation to determine if critical speeds for operating compressors fall within operating range. Data acquisition hardware and software settings will be discussed for measuring liftoff, first critical and second critical speeds. Several tests provided comparisons between an optical displacement probe and accelerometer measurements. Vibration data and analysis of the 20 Tevatron ring cold compressors will be presented

Transcriptomic analysis of pathways regulated by toll-like receptor 4 in a murine model of chronic pulmonary inflammation and carcinogenesis

<p>Abstract</p> <p>Background</p> <p>Therapeutic strategies exist for human pulmonary neoplasia, however due to the heterogeneity of the disease, most are not very effective. The innate immunity gene, toll-like receptor 4 (TLR4), protects against chronic pulmonary inflammation and tumorigenesis in mice, but the mechanism is unclear. This study was designed to identify TLR4-mediated gene expression pathways that may be used as prognostic indicators of susceptibility to lung tumorigenesis in mice and provide insight into the mechanism.</p> <p>Methods</p> <p>Whole lung mRNA was isolated from C.C3H-<it>Tlr4</it>^{<it>Lps</it>-<it>d </it>}(BALB^{<it>Lps</it>-<it>d</it>}; <it>Tlr4 </it>mutant) and BALB/c (<it>Tlr4 </it>normal) mice following butylated hydroxytoluene (BHT)-treatment (four weekly ip. injections; 150-200 mg/kg/each; "promotion"). mRNA from micro-dissected tumors (adenomas) and adjacent uninvolved tissue from both strains were also compared 27 wks after a single carcinogen injection (3-methylcholanthrene (MCA), 10 μg/g; "control") or followed by BHT (6 weekly ip. injections; 125-200 mg/kg/each; "progression"). Bronchoalveolar lavage fluid was analyzed for inflammatory cell content and total protein determination, a marker of lung hyperpermeability; inflammation was also assessed using immunohistochemical staining for macrophages (F4/80) and lymphocytes (CD3) in mice bearing tumors (progression).</p> <p>Results</p> <p>During promotion, the majority of genes identified in the BALB^{<it>Lps</it>-<it>d </it>}compared to BALB/c mice (P < 0.05) were involved in epithelial growth factor receptor (EGFR) signaling (e.g. epiregulin (<it>Ereg</it>)), secreted phosphoprotein 1(<it>Spp1</it>)), which can lead to cell growth and eventual tumor development. Inflammation was significantly higher in BALB^{<it>Lps</it>-<it>d </it>}compared to BALB/c mice during progression, similar to the observed response during tumor promotion in these strains. Increases in genes involved in signaling through the EGFR pathway (e.g. <it>Ereg</it>, <it>Spp1</it>) were also observed during progression in addition to continued inflammation, chemotactic, and immune response gene expression in the BALB^{<it>Lps</it>-<it>d </it>}versus BALB/c mice (<it>P </it>< 0.05), which appears to provide more favorable conditions for cell growth and tumor development. In support of these findings, the BALB/c mice also had significantly reduced expression of many immune response and inflammatory genes in both the tumors and uninvolved tissue.</p> <p>Conclusion</p> <p>This transcriptomic study determined the protective effect of TLR4 in lung carcinogenesis inhibition of multiple pathways including EGFR (e.g. <it>Ereg</it>), inflammatory response genes (e.g. <it>Cxcl5)</it>, chemotaxis (e.g. <it>Ccr1</it>) and other cell proliferation genes (e.g. <it>Arg1</it>, <it>Pthlh</it>). Future studies will determine the utility of these pathways as indicators of immune system deficiencies and tumorigenesis.</p

Diversity, competition, extinction: the ecophysics of language change

As early indicated by Charles Darwin, languages behave and change very much like living species. They display high diversity, differentiate in space and time, emerge and disappear. A large body of literature has explored the role of information exchanges and communicative constraints in groups of agents under selective scenarios. These models have been very helpful in providing a rationale on how complex forms of communication emerge under evolutionary pressures. However, other patterns of large-scale organization can be described using mathematical methods ignoring communicative traits. These approaches consider shorter time scales and have been developed by exploiting both theoretical ecology and statistical physics methods. The models are reviewed here and include extinction, invasion, origination, spatial organization, coexistence and diversity as key concepts and are very simple in their defining rules. Such simplicity is used in order to catch the most fundamental laws of organization and those universal ingredients responsible for qualitative traits. The similarities between observed and predicted patterns indicate that an ecological theory of language is emerging, supporting (on a quantitative basis) its ecological nature, although key differences are also present. Here we critically review some recent advances lying and outline their implications and limitations as well as open problems for future research.Comment: 17 Pages. A review on current models from statistical Physics and Theoretical Ecology applied to study language dynamic

Stable propagation of an ordered array of cracks during directional drying

We study the appearance and evolution of an array of parallel cracks in a thin slab of material that is directionally dried, and show that the cracks penetrate the material uniformly if the drying front is sufficiently sharp. We also show that cracks have a tendency to become evenly spaced during the penetration. The typical distance between cracks is mainly governed by the typical distance of the pattern at the surface, and it is not modified during the penetration. Our results agree with recent experimental work, and can be extended to three dimensions to describe the properties of columnar polygonal patterns observed in some geological formations.Comment: 8 pages, 4 figures, to appear in PR

Measurements of SCRF cavity dynamic heat load in horizontal test system

The Horizontal Test System (HTS) at Fermilab is currently testing fully assembled, dressed superconducting radio frequency (SCRF) cavities. These cavities are cooled in a bath of superfluid helium at 1.8K. Dissipated RF power from the cavities is a dynamic heat load on the cryogenic system. The magnitude of heat flux from these cavities into the helium is also an important variable for understanding cavity performance. Methods and hardware used to measure this dynamic heat load are presented. Results are presented from several cavity tests and testing accuracy is discussed

Insulin-like growth factor-binding protein-2 promotes prostate cancer cell growth via IGF-dependent or -independent mechanisms and reduces the efficacy of docetaxel

Background: The development of androgen independence, chemo-, and radioresistance are critical markers of prostate cancer progression and the predominant reasons for its high mortality. Understanding the resistance to therapy could aid the development of more effective treatments. Aim: The aim of this study is to investigate the effects of insulin-like growth factor-binding protein-2 (IGFBP-2) on prostate cancer cell proliferation and its effects on the response to docetaxel. Methods: DU145 and PC3 cells were treated with IGFBP-2, insulin-like growth factor I (IGF-I) alone or in combination with blockade of the IGF-I receptor or integrin receptors. Cells were also treated with IGFBP-2 short interfering ribonucleic acid with or without a PTEN (phosphatase and tensin homologue deleted on chromosome 10) inhibitor or docetaxel. Tritiated thymidine incorporation was used to measure cell proliferation and Trypan blue cell counting for cell death. Levels of IGFBP-2 mRNA were measured using RT-PCR. Abundance and phosphorylation of proteins were assessed using western immunoblotting. Results: The IGFBP-2 promoted cell growth in both cell lines but with PC3 cells this was in an IGF-dependent manner, whereas with DU145 cells the effect was independent of IGF receptor activation. This IGF-independent effect of IGFBP-2 was mediated by interaction with β-1-containing integrins and a consequent increase in PTEN phosphorylation. We also determined that silencing IGFBP-2 in both cell lines increased the sensitivity of the cells to docetaxel. Conclusion: The IGFBP-2 has a key role in the growth of prostate cancer cells, and silencing IGFBP-2 expression reduced the resistance of these cells to docetaxel. Targeting IGFBP-2 may increase the efficacy of docetaxel.7 page(s