Composition and Physical Properties of Enceladus' Surface

Observations of Saturn’s satellite Enceladus using Cassini’s Visual and Infrared Mapping Spectrometer instrument were obtained during three flybys of Enceladus in 2005. Enceladus’ surface is composed mostly of nearly pure water ice except near its south pole, where there are light organics, CO2, and amorphous and crystalline water ice, particularly in the region dubbed the ‘‘tiger stripes.’’ An upper limit of 5 precipitable nanometers is derived for CO in the atmospheric column above Enceladus, and 2% for NH3 in global surface deposits. Upper limits of 140 kelvin (for a filled pixel) are derived for the temperatures in the tiger stripes

Outcomes of patients with drug-resistant-tuberculosis treated with bedaquiline-containing regimens and undergoing adjunctive surgery

Objectives: No study evaluated the contribution of adjunctive surgery in bedaquiline-treated patients. This study describes treatment outcomes and complications in a cohort of drug-resistant pulmonary tuberculosis (TB) cases treated with bedaquiline-containing regimens undergoing surgery.Methods: This retrospective observational study recruited patients treated for TB in 12 centres in 9 countries between January 2007 and March 2015.Patients who had surgical indications in a bedaquiline-treated programme-based cohort were selected and surgery-related information was collected. Patient characteristics and surgical indications were described together with type of operation, surgical complications, bacteriological conversion rates, and treatment outcomes. Treatment outcomes were evaluated according to the time of surgery.Results: 57 bedaquiline-exposed cases resistant to a median of 7 drugs had indication for surgery (52 retreatments; 50 extensively drug-resistant (XDR) or pre XDR-TB). Sixty percent of cases initiated bedaquiline treatment following surgery, while 36.4% underwent the bedaquiline regimen before surgery and completed it after the operation. At treatment completion 90% culture-converted with 69.1% achieving treatment success; 21.8% had unfavourable outcomes (20.0% treatment failure, 1.8% lost to follow-up), and 9.1% were still undergoing treatment.Conclusions: The study results suggest that bedaquiline and surgery can be safely and effectively combined in selected cases with a specific indication. (C) 2018 The British Infection Association. Published by Elsevier Ltd. All rights reserved

Detection of exposed H2O ice on the nucleus of comet 67P/Churyumov-Gerasimenko

Context. Since the orbital insertion of the Rosetta spacecraft, comet 67P/Churyumov-Gerasimenko (67P) has been mapped by OSIRIS camera and VIRTIS spectro-imager, producing a huge quantity of images and spectra of the comet’s nucleus. Aims. The aim of this work is to search for the presence of H2O on the nucleus which, in general, appears very dark and rich in dehydrated organic material. After selecting images of the bright spots which could be good candidates to search for H2O ice, taken at high resolution by OSIRIS, we check for spectral cubes of the selected coordinates to identify these spots observed by VIRTIS. Methods. The selected OSIRIS images were processed with the OSIRIS standard pipeline and corrected for the illumination conditions for each pixel using the Lommel-Seeliger disk law. The spots with higher I/F were selected and then analysed spectrophotometrically and compared with the surrounding area. We selected 13 spots as good targets to be analysed by VIRTIS to search for the 2 μm absorption band of water ice in the VIRTIS spectral cubes. Results. Out of the 13 selected bright spots, eight of them present positive H2O ice detection on the VIRTIS data. A spectral analysis was performed and the approximate temperature of each spot was computed. The H2O ice content was confirmed by modeling the spectra with mixing (areal and intimate) of H2O ice and dark terrain, using Hapke’s radiative transfer modeling. We also present a detailed analysis of the detected spots