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The Interuniversity Attraction Pole (IAP) 'PLANET TOPERS' (Planets: Tracing the Transfer, Origin, Preservation, and Evolution of their Reservoirs) addresses the fundamental understanding of the thermal and compositional evolution of the different reservoirs of planetary bodies (core, mantle, crust, atmosphere, hydrosphere, cryosphere, and space) considering interactions and feedback mechanisms. Here we present the first results after 2 years of project work. [ABSTRACT FROM AUTHOR]

Lacking plate tectonics and crustal recycling, the long-term evolution of the crust-mantle system of Mars is driven by mantle convection, partial melting, and silicate differentiation. Volcanic landforms such as lava flows, shield volcanoes, volcanic cones, pyroclastic deposits, and dikes are observed on the martian surface, and while activity was widespread during the late Noachian and Hesperian, volcanism became more and more restricted to the Tharsis and Elysium provinces in the Amazonian period. Martian igneous rocks are predominantly basaltic in composition, and remote sensing data, in-situ data, and analysis of the SNC meteorites indicate that magma source regions were located at depths between 80 and 150 km, with degrees of partial melting ranging from 5 to 15 %. Furthermore, magma storage at depth appears to be of limited importance, and secular cooling rates of 30 to 40 K Gyr were derived from surface chemistry for the Hesperian and Amazonian periods. These estimates are in general agreement with numerical models of the thermo-chemical evolution of Mars, which predict source region depths of 100 to 200 km, degrees of partial melting between 5 and 20 %, and secular cooling rates of 40 to 50 K Gyr. In addition, these model predictions largely agree with elastic lithosphere thickness estimates derived from gravity and topography data. Major unknowns related to the evolution of the crust-mantle system are the age of the shergottites, the planet's initial bulk mantle water content, and its average crustal thickness. Analysis of the SNC meteorites, estimates of the elastic lithosphere thickness, as well as the fact that tidal dissipation takes place in the martian mantle indicate that rheologically significant amounts of water of a few tens of ppm are still present in the interior. However, the exact amount is controversial and estimates range from only a few to more than 200 ppm. Owing to the uncertain formation age of the shergottites it is unclear whether these water contents correspond to the ancient or present mantle. It therefore remains to be investigated whether petrologically significant amounts of water of more than 100 ppm are or have been present in the deep interior. Although models suggest that about 50 % of the incompatible species (HO, K, Th, U) have been removed from the mantle, the amount of mantle differentiation remains uncertain because the average crustal thickness is merely constrained to within a factor of two. [ABSTRACT FROM AUTHOR]

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Mars Environment and Magnetic Orbiter was proposed as an answer to the Cosmic Vision Call of Opportunity as a M-class mission. The MEMO mission is designed to study the strong interconnections between the planetary interior, atmosphere and solar conditions essential to understand planetary evolution, the appearance of life and its sustainability. MEMO provides a high-resolution, complete, mapping of the magnetic field (below an altitude of about 250 km), with an yet unachieved full global coverage. This is combined with an in situ characterization of the high atmosphere and remote sensing of the middle and lower atmospheres, with an unmatched accuracy. These measurements are completed by an improved detection of the gravity field signatures associated with carbon dioxide cycle and to the tidal deformation. In addition the solar wind, solar EUV/UV and energetic particle fluxes are simultaneously and continuously monitored. The challenging scientific objectives of the MEMO mission proposal are fulfilled with the appropriate scientific instruments and orbit strategy. MEMO is composed of a main platform, placed on a elliptical (130 × 1,000 km), non polar (77° inclination) orbit, and of an independent, higher apoapsis (10,000 km) and low periapsis (300 km) micro-satellite. These orbital parameters are designed so that the scientific return of MEMO is maximized, in terms of measurement altitude, local time, season and geographical coverage. MEMO carry several suites of instruments, made of an ‘exospheric-upper atmosphere’ package, a ‘magnetic field’ package, and a ‘low-middle atmosphere’ package. Nominal mission duration is one Martian year. [ABSTRACT FROM AUTHOR]

There is a lack of representative prevalence rates for attention deficit-/hyperactivity disorder (ADHD) according to DSM-IV criteria and hyperkinetic disorder (HD) according to ICD-10 criteria for German subjects. To report the results of analyses of categorical data on the prevalence rates of the symptoms of ADHD/HD and additional diagnostic criteria, as well as of the diagnoses of ADHD and HD according to symptoms and other diagnostic criteria, according to the ICD-10 and DSM-IV. Further, to report administrative prevalence rates of the diagnosis and rates of co-existing behavioural and emotional problems. Within the BELLA module of the German Health Interview and Examination Survey for Children and Adolescents (KiGGS), a representative sample of parents of 2,452 children and adolescents aged 7-17 years completed an ADHD symptom checklist (FBB-HKS/ADHS) and additional questionnaires for the assessment of coexisting behavioural and emotional problems. The prevalence rates for the diagnoses of ADHD according to DSM-IV criteria were 5.0% and the rate for HD according to ICD-10 criteria was 1.0%. Higher prevalence rates were found in boys and in younger children. The addition of other diagnostic criteria (impairment, pervasiveness, onset, duration) resulted in a significant decrease of the prevalence rates of ADHD and HD to 2.2 and 0.6%, respectively. Higher prevalence rates were found in families of lower socioeconomic status and families from urban areas. The lifetime administrative prevalence rate was 6.5%. Children with ADHD had an increased risk for coexisting behavioural and emotional problems, especially for aggressive and antisocial behaviour problems, but also for anxiety and mood problems. The results of the national sample are in line with community studies in other countries. The effects of the additional diagnostic criteria of impairment, situational pervasiveness, symptom onset and symptom duration on the prevalence rates have to be considered in other epidemiological studies. [ABSTRACT FROM AUTHOR]

In light of assessing the habitability of Mars, we examine the impact of the magnetic field on the atmosphere. When there is a magnetic field, the atmosphere is protected from erosion by solar wind. The magnetic field ensures the maintenance of a dense atmosphere, necessary for liquid water to exist on the surface of Mars. We also examine the impact of the rotation of Mars on the magnetic field. When the magnetic field of Mars ceased to exist (about 4 Gyr ago), atmospheric escape induced by solar wind began. We consider scenarios which could ultimately lead to a decrease of atmospheric pressure to the presently observed value of 7 mbar: a much weaker early martian magnetic field, a late onset of the dynamo, and high erosion rates of a denser early atmosphere. [ABSTRACT FROM AUTHOR]

In our search for life on other planets over the past decades, we have come to understand that the solid terrestrial planets provide much more than merely a substrate on which life may develop. Large-scale exchange of heat and volatile species between planetary interiors and hydrospheres/atmospheres, as well as the presence of a magnetic field, are important factors contributing to the habitability of a planet. This chapter reviews these processes, their mutual interactions, and the role life plays in regulating or modulating them. [ABSTRACT FROM AUTHOR]

The stationary probability distribution of a two-phase queueing system with a finite or an infinite buffer for the first phase and a finite buffer for the second phase is derived. The input flow of the system is a batch Markov arrival process. Both phases have single-servers. The service time distribution is arbitrary for the first phase and of phase-type for the second phase. If the buffer of the second phase is full at the instant of completion of service at the first phase, the first server is blocked until the buffer is freed. [ABSTRACT FROM AUTHOR]

Presents simulations of mantle convection at the end of the late Archaean. Impact of the occurrence of a two-layer convection or flush instability; Archaean eon as period of profound geological changes; Increase in the intensity of the geomagnetic field at the end of the Huronian glaciation.