46 research outputs found
Simultaneous PIXE and RBS data analysis using Bayesian Inference with the DataFurnace code
The Rutherford Backscattering Spectroscopy (RBS) and Particle Induced X-ray
Emission (PIXE) techniques can be used to obtain complementary information
about the characteristics of a sample but, traditionally, a gap has separated
the available computer codes for analyzing data from each technique, being hard
to simultaneously analyze data from the same sample. The recent development of
a free and open source library, LibCPIXE, for PIXE simulation and analysis of
arbitrary multilayered samples, has permitted to integrate this technique into
the DataFurnace code which already handles many other IBA techniques such as
Rutherford and non-Rutherford backscattering, elastic recoil detection, and
non-resonant nuclear reaction analysis. The fitting capabilities of DataFurnace
can therefore now be applied to PIXE spectra as well, including the Bayesian
Inference analysis and the simultaneous and coherent fitting of multiple
spectra from different techniques. Various examples are presented in which the
simultaneous RBS and PIXE analysis allows us to obtain consistent results that
cannot be obtained by independent analysis of the data from each technique.Comment: 10 pages, 5 figures. Paper initially presented to IBA2005. Please
cite the published version (DOI:10.1016/j.nimb.2006.03.190
LibCPIXE: a PIXE simulation open-source library for multilayered samples
Most particle induced X-ray emission (PIXE) data analysis codes are not
focused on handling multilayered samples. We have developed an open-source
library called "LibCPIXE", for PIXE data analysis. It is written in standard C
and implements functions for simulating X-ray yields of PIXE spectra taken from
arbitrary samples, including multilayered targets. The library is designed to
be fast, portable, modular and scalable, as well as to facilitate its
incorporation into any existing program. In order to demonstrate the
capabilities of the library, a program called CPIXE was developed and used to
analyze various real samples involving both bulk and layered samples. Just as
the library, the CPIXE source code is freely available under the General Public
License. We demonstrate that it runs both under GNU/Linux systems as well as
under MS Windows. There is in principle no limitation to port it to other
platforms
Smoking and plasma fibrinogen, lipoprotein (a) and serotinin are markers for postoperative infrainguinal graft stenosis
Objectives:A number of systemic variables are associated with infrainguinal graft failure and also with experimental smooth muscle hyperplasia. Stenosis is the most common cause of infrainguinal graft thrombosis but it is not known if systemic variables are associated with stenosis.Design, materials and methods:In this study, clinical and serological factors were measured and correlated with stenosis development in 81 infrainguinal bypass grafts (52 vein, 29 PTFE; 28 with stenosis) in prospective (n = 46) and retrospective (n = 35) groups. Pre-existing stenosis was ecluded by perioperative graft assessment.Results:There was a significantly greater proportion of smokers in the patients who developed stenosis (11/18; 61%) compared with those who did not (6/28; 21%, p = 0.006; x2). Patients who developed stenosis also had significantly (Mann Whitney U-tests), higher circulating levels of [median (interquartile range)] fibrinogen (412.5 (356–484.5) vs. 339 (300–397.7) mg/100ml, p = 0.003), Lipoprotein (a) (0.20 (0.05–0.45) vs. 0.085 (0.05–0.23), g/l, p = 0.03) and 5-hydroxytryptamine (14.1 (6.6–45) vs. 4.41 (3–8.39) nmol/l, p = 0.005), than those without stenosis.By logistic regression, these associations were independent of graft material and whether grafts were studied prospectively or retrospectively.Conclusions:Smoking and plasma fibrinogen, Lp(a) and 5-hydroxytryptamine are markers for postoperative infrainguinal graft stenosis
Composition measurement of epitaxial Sc<inf>x</inf>Ga<inf>1-x</inf>N films
Four different methods for measuring the compositions of epitaxial ScxGa1-xN films were assessed and compared to determine which was the most reliable and accurate. The compositions of epitaxial ScxGa1-xN films with 0 ≤ x ≤ 0.26 were measured directly using Rutherford backscattering (RBS) and x-ray photoelectron spectroscopy (XPS), and indirectly using c lattice parameter measurements from x-ray diffraction and c/a ratio measurements from electron diffraction patterns. RBS measurements were taken as a standard reference. XPS was found to underestimate the Sc content, whereas c lattice parameter and c/a ratio were not reliable for composition determination due to the unknown degree of strain relaxation in the film. However, the Sc flux used during growth was found to relate linearly with x and could be used to estimate the Sc content
H^+ -> W^+ l_i^- l_j^+$ decay in the two Higgs doublet model
We study the lepton flavor violating H^+ -> W^+ l_i^- l_j^+ and the lepton
flavor conserving $H^+ -> W^+ l_i^- l_i^+ (l_i=\tau, l_j=\mu) decays in the
general 2HDM, so called model III. We estimate the decay width \Gamma for LFV
(LFC) at the order of the magnitude of (10^{-11}-10^{-5}) GeV
((10^{-9}-10^{-4}) GeV), for 200 GeV\leq m_{H^\pm}\leq 400
GeV, and the intermediate values of the coupling
\bar{\xi}^{E}_{N,\tau \mu}\sim 5 GeV (\bar{\xi}^{E}_{N,\tau
\tau}\sim 30 GeV). We observe that the experimental result of the process
under consideration can give comprehensive information about the physics beyond
the standard model and the existing free parameters.Comment: 8 pages, 7 Figure
Effects of Intermittent IL-2 Alone or with Peri-Cycle Antiretroviral Therapy in Early HIV Infection: The STALWART Study
The Study of Aldesleukin with and without antiretroviral therapy (STALWART) evaluated whether intermittent interleukin-2 (IL-2) alone or with antiretroviral therapy (ART) around IL-2 cycles increased CD4+ counts compared to no therapy
Use of SMS texts for facilitating access to online alcohol interventions: a feasibility study
A41 Use of SMS texts for facilitating access to online alcohol interventions: a feasibility study
In: Addiction Science & Clinical Practice 2017, 12(Suppl 1): A4