350 research outputs found

    The Role of Local Therapy in Multi-focal Epithelioid Haemangioendothelioma

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    Contains fulltext : 208930.pdf (publisher's version ) (Open Access)BACKGROUND/AIM: Epithelioid haemangioendothelioma (EHE) is a rare tumor with a wide spectrum of clinical behavior. There is no consensus on the role of local therapy in symptomatic, multi-focal disease. PATIENTS AND METHODS: A retrospective review of patients presenting to the Royal Marsden Hospital between January 2000 and December 2017 was conducted. RESULTS: Fifty-three patients with EHE were identified, of which 18 patients (34.0%) received local therapy, and 11 patients (20.8%) underwent active surveillance. A variety of local treatment modalities were used with few toxicities, and local recurrence was managed with other local treatments or systemic therapy. Distal disease progression was infrequent (n=4, 7.5%). Patients who developed pleural effusion (n=5, 9.4%) had poor outcome irrespective of treatment. CONCLUSION: Local therapy has a role in a selected patient group managed in a multidisciplinary setting, including patients with indolent disease, and patients with a solitary area of progression/symptomatic disease

    Reproductive health operations research, 1995–1998

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    This book presents in-depth reports on promising new interventions that have been developed and important programmatic changes that have been achieved by operations research in Latin America between 1995 and 1998. The INOPAL III project has made advances in five areas including access and quality of services, integration of family planning and other reproductive health services, financial sustainability, post-abortion care, and emergency contraception. Each of these topics are represented by at least three studies conducted in two or more countries. The operations research projects discussed under each topic are not replications of a single study. They use different research designs and address different questions. Nevertheless, when taken together, they provide managers and decision-makers with a body of programmatically relevant information on each broad topic covered

    (INVITED) Methods for determining the refractive indices and thermo-optic coefficients of chalcogenide glasses at MIR wavelengths

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    Chalcogenide glasses have attracted much attention for the realization of photonic components owing to their outstanding optical properties in the mid-infrared (MIR) region. However, relatively few refractive index dispersion data are presently available for these glasses at MIR wavelengths. This paper presents a mini review of methods we have both used and developed to determine the refractive indices and thermo-optic coefficients of chalcogenide glasses at MIR wavelengths, and is supported by new results. The mini review should be useful to both new and established researchers in the chalcogenide glass field and fields of MIR optics, fiber-optics and waveguides. Three groups of methods are distinguished: (1) spectroscopic ellipsometry, (2) prism-based methods, and (3) methods using Fourier transform infrared (FTIR) transmission data. The mini review is supported by a brief discussion of refractive index models

    Determining the refractive index dispersion and thickness of hot-pressed chalcogenide thin films from an improved Swanepoel method

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    The well-known method presented by Swanepoel can be used to determine the refractive index dispersion of thin films in the near-infrared region from wavelength values at maxima and minima, only, of the transmission interference fringes. In order to extend this method into the mid-infrared (MIR) spectral region (our measurements are over the wavelength range from 2 to 25 μm), the method is improved by using a two-term Sellmeier model instead of the Cauchy model as the dispersive equation. Chalcogenide thin films of nominal batch composition As40Se60 (atomic %) and Ge16As24Se15.5Te44.5 (atomic %) are prepared by a hot-pressing technique. The refractive index dispersion of the chalcogenide thin films is determined by the improved method with a standard deviation of less than 0.0027. The accuracy of the method is shown to be better than 0.4% at a wavelength of 3.1 μm by comparison with a benchmark refractive index value obtained from prism measurements on Ge16As24Se15.5Te44.5 material taken from the same batch

    Broadband, mid-infrared emission from Pr3+ doped GeAsGaSe chalcogenide fiber, optically clad

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    We present a study of mid-infrared photoluminescence in the wavelength range 3.5–5.5lm emitted from Pr3+: GeAsGaSe core/GeAsGaSe cladding chalcogenide fiber. The Pr3+doped fiber optic preform is fabricated using extrusion and is successfully drawn to low optical loss, step-index fiber. Broadband mid-infrared photoluminescence is observed from the fiber, both under 1.55microns or 1.94 microns wavelength excitation. Absorption, and emission, spectra of bulk glass and fiber are presented. Luminescent lifetimesare measured for the fiber and the Judd–Ofelt parameters are calculated. The radiative transition rates calculated from Judd–Ofelt theory are compared with experimental lifetimes. The observed strong broad-band emission suggests that this type of fiber is a good candidate for further development to realize both fiber lasers and amplified spontaneous emission fiber sources in the mid-infrared region

    Boson-fermion stars: exploring different configurations

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    We use the flexibility of the concept of a fermion-boson star to explore different configurations, ranging from objects of atomic size and masses of the order 101810^{18} g, up to objects of galactic masses and gigantic halos around a smaller core, with possible interesting applications to astrophysics and cosmology, particularly in the context of dark matter.Comment: 8 pages. Minor changes, new reference added and a few typos correcte

    Determining small refractive index contrast in chalcogenide-glass pairs at mid-infrared wavelengths

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    A two-composition thin film (Ge20Sb10Se70/Ge20Sb10Se67S3 atomic%core/cladding glasses) was fabricated using a hot-fibre-pressing technique in which both glasses follow the same post-fibre processing. A simple approach is proposed that uses normal incidence transmission spectra to determine their refractive index contrast over the wavelength range from 2 to 25 μm with an error of less than _ 0.002. Using an improved Swanepoel method, the calculated numerical aperture of these two compositions was within _ 0.011 of that obtained from prism minimum deviation measurements. Results show that introducing 3 atomic % S into the Ge-Sb-Se glass system lowered the refractive index and blue-shifted the visible optical bandgap, the far-infrared fundamental vibrational absorption bands and the zero-dispersion wavelength

    Study of the production of Λb0\Lambda_b^0 and B0\overline{B}^0 hadrons in pppp collisions and first measurement of the Λb0J/ψpK\Lambda_b^0\rightarrow J/\psi pK^- branching fraction

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    The product of the Λb0\Lambda_b^0 (B0\overline{B}^0) differential production cross-section and the branching fraction of the decay Λb0J/ψpK\Lambda_b^0\rightarrow J/\psi pK^- (B0J/ψK(892)0\overline{B}^0\rightarrow J/\psi\overline{K}^*(892)^0) is measured as a function of the beauty hadron transverse momentum, pTp_{\rm T}, and rapidity, yy. The kinematic region of the measurements is pT<20 GeV/cp_{\rm T}<20~{\rm GeV}/c and 2.0<y<4.52.0<y<4.5. The measurements use a data sample corresponding to an integrated luminosity of 3 fb13~{\rm fb}^{-1} collected by the LHCb detector in pppp collisions at centre-of-mass energies s=7 TeV\sqrt{s}=7~{\rm TeV} in 2011 and s=8 TeV\sqrt{s}=8~{\rm TeV} in 2012. Based on previous LHCb results of the fragmentation fraction ratio, fΛB0/fdf_{\Lambda_B^0}/f_d, the branching fraction of the decay Λb0J/ψpK\Lambda_b^0\rightarrow J/\psi pK^- is measured to be \begin{equation*} \mathcal{B}(\Lambda_b^0\rightarrow J/\psi pK^-)= (3.17\pm0.04\pm0.07\pm0.34^{+0.45}_{-0.28})\times10^{-4}, \end{equation*} where the first uncertainty is statistical, the second is systematic, the third is due to the uncertainty on the branching fraction of the decay B0J/ψK(892)0\overline{B}^0\rightarrow J/\psi\overline{K}^*(892)^0, and the fourth is due to the knowledge of fΛb0/fdf_{\Lambda_b^0}/f_d. The sum of the asymmetries in the production and decay between Λb0\Lambda_b^0 and Λb0\overline{\Lambda}_b^0 is also measured as a function of pTp_{\rm T} and yy. The previously published branching fraction of Λb0J/ψpπ\Lambda_b^0\rightarrow J/\psi p\pi^-, relative to that of Λb0J/ψpK\Lambda_b^0\rightarrow J/\psi pK^-, is updated. The branching fractions of Λb0Pc+(J/ψp)K\Lambda_b^0\rightarrow P_c^+(\rightarrow J/\psi p)K^- are determined.Comment: 29 pages, 19figures. All figures and tables, along with any supplementary material and additional information, are available at https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2015-032.htm
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