The chemical connection between 67P/C-G and IRAS 16293-2422

The chemical evolution of a star- and planet-forming system begins in the prestellar phase and proceeds across the subsequent evolutionary phases. The chemical trail from cores to protoplanetary disks to planetary embryos can be studied by comparing distant young protostars and comets in our Solar System. One particularly chemically rich system that is thought to be analogous to our own is the low-mass IRAS 16293-2422. ALMA-PILS observations have made the study of chemistry on the disk scales (< 100 AU) of this system possible. Under the assumption that comets are pristine tracers of the outer parts of the innate protosolar disk, it is possible to compare the composition of our infant Solar System to that of IRAS 16293-2422. The Rosetta mission has yielded a wealth of unique in situ measurements on comet 67P/C-G, making it the best probe to date. Herein, the initial comparisons in terms of the chemical composition and isotopic ratios are summarized. Much work is still to be carried out in the future as the analysis of both of these data sets is still ongoing.Comment: To appear in "Astrochemistry VII -- Through the Cosmos from Galaxies to Planets", proceedings of the IAU Symposium No. 332, 2017, Puerto Varas, Chile. M. Cunningham, T. Millar and Y. Aikawa, eds. (6 pages

The gas production of 14 species from comet 67P/Churyumov-Gerasimenko based on DFMS/COPS data from 2014-2016

The coma of comet 67P/Churyumov-Gerasimenko has been probed by the Rosetta spacecraft and shows a variety of different molecules. The ROSINA COmet Pressure Sensor and the Double Focusing Mass Spectrometer provide in-situ densities for many volatile compounds including the 14 gas species H2O, CO2, CO, H2S, O2, C2H6, CH3OH, H2CO, CH4, NH3, HCN, C2H5OH, OCS, and CS2. We fit the observed densities during the entire comet mission between August 2014 and September 2016 to an inverse coma model. We retrieve surface emissions on a cometary shape with 3996 triangular elements for 50 separated time intervals. For each gas we derive systematic error bounds and report the temporal evolution of the production, peak production, and the time-integrated total production. We discuss the production for the two lobes of the nucleus and for the northern and southern hemispheres. Moreover we provide a comparison of the gas production with the seasonal illumination.Comment: 1. uncertainty for gas production with respect to limited surface coverage and to the l2-error for the parameter fit 2. ancillary files to create the plots in figure

An Outbreak of Nontoxigenic Corynebacterium diphtheriae Infection: Single Bacterial Clone Causing Invasive Infection Among Swiss Drug Users

From 1990 to 1996, a total of 65 patients from whom Corynebacterium diphtheriae had been isolated were reported to the Swiss Federal Office of Public Health. A retrospective review of medical and microbiological records as well as results of ribotyping of available isolates was performed. Twenty-seven patients had acquired their infection without evidence of use of illicit drugs, mostly as a skin infection imported from subtropical areas (20 patients); 38 isolations were associated with intravenous drug use (IVDU) (skin, 15; respiratory tract, 10; blood, 13). Endocarditis was documented in nine patients with bloodstream infection, four of whom died. There were two additional deaths due to overwhelming sepsis. The same ribotype of nontoxigenic C. diphtheriae was found in 31 of the 32 examined isolates associated with IVDU. All non-IVDU isolates had different ribotypes. Among Swiss drug users, a single clone of nontoxigenic C. diphtheriae was found over a period of several years with a high potential to cause severe invasive infectio

Ribotyping of Pseudomonas aeruginosa Strains Isolated from Surgical Intensive Care Patients

To elucidate the sources of Pseudomonas aeruginosa on a surgical intensive care unit, rDNA restriction fragment length polymorphism analysis (ribotyping) was applied to analyze strains isolated during a 4-month prospective study. Samples included 1635 from 153 patients, 2463 from 97 staff members, and 581 from the environment. Only 18 patients were colonized. Isolation from their animate and inanimate environment was very low, with 3 and 2 samples, respectively, being positive. Samples from tap water were negative. Ribotyping could easily distinguish 16 different digest patterns with identical follow-up isolates of the same patient. Horizontal transmission occurred only twice. The discriminatory power of ribosomal DNA in differentiating strains was dependent on the restriction enzymes used; among eight different enzymes, PvuII was the most sensitive, producing 15 different patterns. Ribotyping showed high sensitivity in typing P. aeruginosa isolates and confirmed that colonization occurs from endogenous rather than from exogenous source

Disease burden of rotavirus gastroenteritis in children up to 5years of age in two Swiss cantons: paediatrician- and hospital-based surveillance

Rotavirus gastroenteritis (RV GE) is a leading cause of diarrhoea in young children. The purpose of this epidemiological surveillance was to measure the disease burden of RV GE among children <5years of age in two regions of Switzerland, Geneva and Lucerne. One hospital and four paediatricians participated per region. The surveillance lasted from December 2006 to June 2007. The population denominator for calculation of the RV GE incidence rate was the average of the overall study population <5years of age under surveillance during the surveillance period. At the study sites, 513 children with GE were presented. Stool sample was collected and examined in 341 cases, of which 130 were RV positive (38.1%). Informed consent to participate in the study was obtained for 113 RV positive subjects. The overall RV GE incidence rate was 0.97% in Lucerne [lower incidence interval (LCI), 0.71%; upper incidence interval (UCI), 1.2%] compared with 0.65 and in Geneva (LCI, 0.50%; UCI, 0.81%). Disease severity assessments using the Vescari score showed that the RV GE episodes were more severe in Lucerne than in Geneva (14.05 ± 3.05 vs 12.85 ± 2.87), which was confirmed by a higher hospitalisation rate in Lucerne at the study visit (82.9% vs 23.6%). More children had fever in Geneva than in Lucerne (42.9% vs 26.8%), and more children were hospitalised during the follow-up period in Geneva than in Lucerne (14.5% vs 2.5%). Genotyping of RV positive stool samples revealed that both G1 and P8 were the most prevalent types in both regions. There was a statistically significant difference in the distribution frequency of G1 between the two regions (p = 0.039). Assessment of health economic data confirmed the economic burden of RV GE episodes. In conclusion, RV GE episodes are a health burden as well as an economic burden also for the children in a developed country such as Switzerlan