85 research outputs found
State-resolved measurements of single-electron capture in slow Ne7+- and Ne8+-helium collisions
Single-electron capture in collisions of 9 keV x q Ne8+ and Ne7+ ions with He has been studied using cold-target recoil-ion momentum spectroscopy. With an improved apparatus a longitudinal momentum resolution of 0.07 au has been achieved. This momentum component is directly proportional to the difference in the binding energy of the active electron between the final and the initial state. For the first time state- resolved differential cross sections have been determined with respect to the main quantum number, subshell level and spin state of the captured electron. A comparison with recent theoretical results for energy levels in Be-like Ne is given
EUV spectra of highly-charged ions W-W relevant to ITER diagnostics
We report the first measurements and detailed analysis of extreme ultraviolet
(EUV) spectra (4 nm to 20 nm) of highly-charged tungsten ions W to
W obtained with an electron beam ion trap (EBIT). Collisional-radiative
modelling is used to identify strong electric-dipole and magnetic-dipole
transitions in all ionization stages. These lines can be used for impurity
transport studies and temperature diagnostics in fusion reactors, such as ITER.
Identifications of prominent lines from several W ions were confirmed by
measurement of isoelectronic EUV spectra of Hf, Ta, and Au. We also discuss the
importance of charge exchange recombination for correct description of
ionization balance in the EBIT plasma.Comment: 11 pages, 4 figure
Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study
Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p<0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p<0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised
An attempt to correlate ion irradiation behaviour and chemical durability of titanate- and zirconate-based ceramics
International audienceTitanate and zirconate samples from perovskite and pyrochlore families have been submitted to low energy heavy ion irradiation in order to pre-damage their crystalline structure. Samples irradiated below or near their amorphisation threshold were then leached in deionised water at 90 degrees C in static mode while samples irradiated above their amorphisation threshold were leached at 100 degrees C in dynamic mode. Below the amorphisation threshold, only slight effects of the pre-irradiation have been found on the chemical durability of titanate and zirconate from the perovskite family. Above the amorphisation threshold, perovskite surfaces exhibit a stronger hydration and an increase of the growth kinetics of secondary phases identified as TiOOH and ZrOOH compounds mainly. The pre-irradiated pyrochlore (Nd(2)Zr(2)O(7)) exhibits both a higher hydration degree and a higher Nd-Zr surface co-enrichment due to the destabilization of their network by the pre-irradiation. (C) 2008 Elsevier B.V. All rights reserved
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