Observations of the northern seasonal polar cap on Mars III: CRISM/HiRISE observations of spring sublimation

We analyze a series of targeted CRISM and HiRISE observations of seven regions of interest at high latitudes in the Northern polar regions of Mars. These data allow us to investigate the temporal evolution of the composition of the seasonal ice cap during spring, with a special emphasis on peculiar phenomena occurring in the dune fields and in the vicinity of the scarps of the North Polar Layered Deposits (NPLDs). The strength of the spectral signature of CO2 ice continuously decreases during spring whereas the one of H2O ice first shows a strong increase until Ls = 50°. This evolution is consistent with a scenario previously established from analysis of OMEGA data, in which a thin layer of pure H2O ice progressively develops at the surface of the volatile layer. During early spring (Ls < 10°), widespread jet activity is observed by HiRISE while strong spectral signatures of CO2 ice are detected by CRISM. Later, around Ls = 20-40°, activity concentrates at the dune fields where CRISM also detects a spectral enrichment in CO2 ice, consistent with "Kieffer's model" (Kieffer, H.H. [2007]. J. Geophys. Res. 112, E08005. doi:10.1029/2006JE002816) for jet activity. Effects of wind are prominent across the dune fields and seem to strongly influence the sublimation of the volatile layer. Strong winds blowing down the scarps could also be responsible for the significant spatial and temporal variability of the surface ice composition observed close to the NPLD.

Measurement and stability of the pointing of the BepiColombo Laser Altimeter under thermal load

The BepiColombo Laser Altimeter (BELA) has been selected to fly on ESA׳s BepiColombo mission to Mercury. The instrument will be the first European laser altimeter designed for interplanetary flight. This paper describes the setup used to characterize the angular movements of BELA under the simulated environmental conditions that the instrument will encounter when orbiting Mercury. The system comprises a laser transmitter and a receiving telescope, which can move with respect to each other under thermal load. Tests performed using the Engineering Qualification Model show that the setup is accurate enough to characterize angular movements of the instrument components to an accuracy of ≈10 μrad. The qualification instrument is thermally stable to operate during all mission phases around Mercury proving that the transmitter and receiver sections will remain within the alignment requirements during its mission.

Time trends in avoidable cancer mortality in Switzerland and neighbouring European countries 1996-2010.

QUESTION UNDER STUDY What are the trends in avoidable cancer mortality in Switzerland and neighbouring countries? METHODS Mortality data and population estimates 1996-2010 were obtained from the Swiss Federal Statistical Office for Switzerland and the World Health Organization Mortality Database (http://www.who.int/healthinfo/mortality_data/en/) for Austria, Germany, France and Italy. Age standardised mortality rates (ASMRs, European standard) per 100 000 person-years were calculated for the population <75 years old by sex for the following groups of cancer deaths: (1) avoidable through primary prevention; (2) avoidable through early detection and treatment; (3) avoidable through improved treatment and medical care; and (4) remaining cancer deaths. To assess time trends in ASMRs, estimated annual percentage changes (EAPCs) with 95% confidence intervals (95% CIs) were calculated. RESULTS In Switzerland and neighbouring countries cancer mortality in persons <75 years old continuously decreased 1996-2010. Avoidable cancer mortality decreased in all groups of avoidable cancer deaths in both sexes, with one exception. ASMRs for causes avoidable through primary prevention increased in females in all countries (in Switzerland from 16.2 to 20.3 per 100 000 person years, EAPC 2.0 [95% CI 1.4 to 2.6]). Compared with its neighbouring countries, Switzerland showed the lowest rates for all groups of avoidable cancer mortality in males 2008-2010. CONCLUSION Overall avoidable cancer mortality decreased, indicating achievements in cancer care and related health policies. However, increasing trends in avoidable cancer mortality through primary prevention for females suggest there is a need in Switzerland and its European neighbouring countries to improve primary prevention.