15 research outputs found

    β-Arrestin-1 expression and epithelial-to-mesenchymal transition in laryngeal carcinoma.

    Get PDF
    Aim: The novel primary end-point of the present study was to ascertain β-arrestin-1 expression in a cohort of consecutive patients with laryngeal squamous cell carcinoma (LSCC) with information available on their cigarette-smoking habits. A secondary end-point was to conduct a preliminary clinical and pathological investigation into the possible role of β-arrestin-1 in the epithelial-to-mesenchymal transition (EMT), identified by testing for E-cadherin, Zeb1, and Zeb2 expression, in the setting of LSCC. Methods: The expression of β-arrestin-1, E-cadherin, zeb1, and zeb2 was ascertained in 20 consecutive LSCCs. Results: Statistical analysis showed no significant associations between β-arrestin-1 and EMT (based on the expression of E-cadherin, Zeb1, and Zeb2). The combined effect of nicotine and β-arrestin-1 was significantly associated with a shorter disease-free survival ( P=0.01) in our series of LSCC. This latter result was also confirmed in an independent, publicly available LSCC cohort ( P=0.047). Conclusions: Further investigations on larger series (ideally in prospective settings) are needed before we can consider closer follow-up protocols and/or more aggressive treatments for patients with LSCC and a combination of nicotine exposure and β-arrestin-1 positivity in tumor cells at the time of their diagnosis. Further studies on how β-arrestin functions in cancer via different signaling pathways might reveal potential targets for the treatment of even advanced laryngeal malignancies

    Seismic analysis and retrofitting of an existing R.C. highway bridge: investigation through pseudo-dynamic

    Get PDF
    The “Retro” TA project funded by the European commission within the Series-project aims at studying numerically and experimentally the seismic behaviour of an old existing reinforced concrete bridge with portal frame piers and the effectiveness of different isolation systems. In particular, an experimental test campaign will be performed at ELSA Laboratory of JRC (Ispra, Italy). Two piers (scale 1:2.5) will be built and tested using the PsD technique with sub-structuring; the modelling of he entire viaduct is considered along with the non-linear behaviour of each pier, due to bending, shear on the transverse beams and strain penetration effect at the column bases. The comprehensive numerical investigations have shown the high vulnerability of the sample bridge. Consequently two isolation systems (yielding-based and friction-based bearings) have been currently designed and characterized. Because the test will start after the summer 2012, in this paper the relevant issues will be here addressed and discussed.JRC.G.5-European laboratory for structural assessmen

    VERT-X: VERTical X-ray raster-scan facility for ATHENA calibration. The concept design

    Get PDF
    Calibration of the ATHENA telescope is a critical aspect of the project and raises significant difficulties due to the unprecedented size, mass and focal length of the mirror assembly. The VERT-X project, financed by ESA and started in January 2019 by a Consortium led by INAF and which includes EIE, Media Lario Technologies, GPAP, and BCV Progetti, aims to design an innovative calibration facility. In the VERT-X design the parallel beam, needed for calibration, is produced placing a source in the focus of an X-ray collimator. This system is mounted on a raster-scan mechanism which covers the entire ATHENA optics. The compactness of the VERT-X design allows a vertical geometry for the ATHENA calibration facility, with several potential benefits with respect to the long horizontal tube calibration facilities

    Silicon pore optics mirror modules for inner and outer radii

    Get PDF
    Athena (Advanced Telescope for High Energy Astrophysics) is an x-ray observatory using a Silicon Pore Optics telescope and was selected as ESA's second L-class science mission for a launch in 2028. The x-ray telescope consists of several hundreds of mirror modules distributed over about 15-20 radial rings. The radius of curvature and the module sizes vary among the different radial positions of the rings resulting in different technical challenges for mirror modules for inner and outer radii. We present first results of demonstrating Silicon Pore Optics for the extreme radial positions of the Athena telescope. For the inner most radii (0.25 m) a new mirror plate design is shown which overcomes the challenges of larger curvatures, higher stress values and bigger plates. Preliminary designs for the mounting system and its mechanical properties are discussed for mirror modules covering all other radial positions up to the most outer radius of the Athena telescope

    Simulating the optical performances of the ATHENA x-ray telescope optics

    Get PDF
    The ATHENA (Advanced Telescope for High Energy Astrophysics) X-ray observatory is an ESA-selected L2 class mission. In the proposed configuration, the optical assembly has a diameter of 2.2 m with an effective area of 1.4 m2 at 1 keV, 0.25 m2 at 6 keV, and requires an angular resolution of 5 arcsec. To meet the requirements of effective area and angular resolution, the technology of Silicon Pore Optics (SPO) was selected for the optics implementation. The ATHENA's optic assembly requires hundreds of SPOs mirror modules (MMs), obtained by stacking wedged and ribbed silicon wafer plates onto silicon mandrels to form the Wolter-I configuration. Different factors can contribute to limit the imaging performances of SPOs, such as i) diffraction through the pore apertures, ii) plate deformations due to fabrication errors and surface roughness, iii) alignment errors among plates in an MM, and iv) co-focality errors within the MMs assembly. In order to determine the fabrication and assembling tolerances, the impact of these contributions needs to be assessed prior to manufacturing. A set of simulation tools responding to this need was developed in the framework of the ESA-financed projects SIMPOSIuM and ASPHEA. In this paper, we present the performance simulation obtained for the recentlyproposed ATHENA configuration in terms of effective area, and we provide a simulation of the diffractive effects in a pair of SPO MMs. Finally, we present an updated sizing of magnetic diverter (a Halbach array) and the magnetic fields levels that can be reached in order to deviate the most energetic protons out of the detector field
    corecore