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The employment of Electrical Propulsion, to reduce the cost of satellites, has also increasedthe use of large solar arrays. Such solar panels are associated with low-frequency resonantmodes, and to ensure fine pointing of the satellite, the attitude control should not excitethese modes. This is a difficult task in such complex systems, whose exact a prioriknowledge is largely unavailable during the early design phase.The primary scope of this thesis is to synthesize a robust algorithm for attitude controlthat deals with modeling errors.The first part is dedicated to understanding the principal causes of uncertainty thatwill inevitably limit the design. Once a description of the uncertainty has been obtained,two different approaches to robust control algorithms have been investigated. The outcomeis the syntheses of two multivariable controllers with different performance and stabilitymargins. Since this project has been carried out during the development of a new fullelectric spacecraft concept by OHB, it has been possible to validate the two controllersin the on-board software simulator of the spacecraft. The results confirm the robustcontrollers as possible alternatives to the current design. Införandet av Elektrisk Framdrivning för att reducera kostnaden för satelliter har ocksåökat användningen av stora solpaneler. Sådana stora solpaneler är associerade medlågfrekventa resonanta moder och för att säkerställa satellitens prestanda får attitydkontrolleninte exitera dessa moder. Detta är en svår uppgift i sådana komplicerade systemför vilka exakt a priori kunskap till stora delar inte finns tillgänglig under projektets tidigadesignfas.Det här examensarbetet handlar i första hand om att syntetisera en robust algoritmför attitydkontroll vilken hanterar modelleringsfel. Första delen av arbetet avser attförstå vilka de primära osäkerhetskällor som begränsar systemets prestanda. Efter att enosäkerhetsbeskrivning har tagits fram undersöks två olika tillvägagångssätt för att ta framrobusta styralgoritmer. Resultatet är synteser av två olika multivariabla regulatorer medolika prestanda och stabilitetsmarginaler. Eftersom projektet har genomförts samtidigtsom OHB har utvecklat en satellitplattform baserad helt på Elektrisk Framdrivning, hardet varit möjligt att validera de två regulatorerna i ombordmjukvarans simulatormiljö.Resultaten bekräftar att de robusta regulatorerna är möjliga alternativ till nuvarandedesign.

Age-related macular degeneration (AMD) is the most common cause of visual loss in developed countries, with a significant economic and social burden on public health. Although genome-wide and gene-candidate studies have been enabled to identify genetic variants in the complement system associated with AMD pathogenesis, the effect of gene-environment interaction is still under debate. In this review we provide an overview of the role of complement system and its genetic variants in AMD, summarizing the consequences of the interaction between genetic and environmental risk factors on AMD onset, progression, and therapeutic response. Finally, we discuss the perspectives of current evidence in the field of genomics driven personalized medicine and public health.

We propose a structural model for the lithosphere-asthenosphere system for the Italic region by means of the S-wave velocity (VS) distribution with depth. To obtain the velocity structure the following methods are used in the sequence: frequency-time analysis (FTAN); 2D tomography (plotted on a grid 1°×1°); non-linear inversion; smoothing optimization method. The 3D VS structure (and its uncertainties) of the study region is assembled as a juxtaposition of the selected representative cellular models. The distribution of seismicity and heat flow is used as an independent constraint for the definition of the crustal and lithospheric thickness. The moment tensor inversion of recent damaging earthquakes which occurred in the Italic region is performed through a powerful non-linear technique and it is related to the different rheologic-mechanic properties of the crust and uppermost mantle. The obtained picture of the lithosphere-asthenosphere system for the Italic region confirms a mantle extremely vertically stratified and laterally strongly heterogeneous. The lateral variability in the mantle is interpreted in terms of subduction zones, slab dehydration, inherited mantle chemical anisotropies, asthenospheric upwellings, and so on. The western Alps and the Dinarides have slabs with low dip, whereas the Apennines show a steeper subduction. No evidence for any type of mantle plume are observed. The asymmetric expansion of the Tyrrhenian Sea, which may be interpreted as related to a relative eastward mantle flow with respect to the overlying lithosphere, is confirmed. Keywords: Italy, surface waves, tomography, non-linear inversion, seismicity, lithosphere-asthenosphere, geodynamics

Subependymoma was first described by Scheinker in 1945; it frequently occurs in the ventricles and rarely in the spinal canal representing 0.7% of all central nervous system tumours. Most of these intraventricular tumours are subclinical entities, remaining of small size and discovered at autopsy with 0.4%incidence. We report a case of subependymoma with a completely exophytic growth from the foramen of Luscka: only a similar one has been described in the literature but with a lesser cysternal involvement. Neuroradiological and anatomopathological features of subependymoma are discussed.