Thèse de doctorat : Université de Fribourg, 2001 ; no 1365.
The major aim of this study is to describe in a detailed manner the 20th century minimum and maximum temperature variations in Switzerland and to assess whether the magnitude of the secular warming and its interannual to interdecadal fluctuations show common seasonal patterns in different climatological regions. In a first step different climatological regions could successfully be...
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Thèse de doctorat : Université de Fribourg, 2003 ; no 1405.
During senescence, chlorophyll of higher plants is degraded into linear tetrapyrrolic catabolites. Their in vitro oxidation with chromic acid furnishes the constituting pyrrolic moieties as maleimides fragments. The substitution patterns of the isolated maleimides are related to the catabolites structures. All maleimides bear the characteristic methyl group of the former chlorophyll as well as a...
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Thèse de doctorat : Université de Fribourg, 2003 ; no 1417.
Deep landslides (> 10 m) are generally characterized by phases of acceleration alternating with periods of lull, but most often lack real stabilization. Due to the continuous movement, it is difcult to evaluate the evolution of the activity. Therefore, a new methodology has been developed in order to precisely identify the sub-recent (20th century) and present evolution of deep landslide...
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Thèse de doctorat : Université de Fribourg, 2001 ; no 1334.
Many neurons and axons are eliminated during the development of the nervous system. These cells and their connections are thus overproduced, and the organism has to destroy the surplus in order to function correctly. A major mechanism responsible for this elimination appears to be competition between cells for a substance necessary for their survival. To examine this hypothesis, the present work...
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Thèse de doctorat : Université de Fribourg, 2001 ; no 1338.
In response to infection by pathogens, plants deploy various and complex defense mechanisms. Resistance can be expressed locally and systemically, depending on the nature of the inducing stimulus. For instance, after infection by a necrotizing pathogen, resistance develops throughout the plants, in tissues distant from the initial site of infection. This form of resistance, called systemic...
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Thèse de doctorat : Université de Fribourg, 2012 ; no. 1762.
This thesis is a collection of properties and applications of linear barycentric rational interpolation, mainly with the weights presented by Floater and Hormann in 2007. We are motivated by the counterintuitive and provable impossibility of constructing from equispaced data an approximation scheme that converges very rapidly to the approximated function and is simultaneously computationally...
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Thèse de doctorat : Université de Fribourg, 2008 ; no 1614.
Knowledge and information make our lives easier and more enjoyable. In this thesis we use techniques and concepts from statistical physics and probability theory to explore several models of complex systems where information plays a prominent role. When building these models we tried to capture main aspects of real systems but also to keep the models simple and analytically solvable. We begin the...
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Thèse de doctorat : Université de Fribourg, 2001 ; no 1345.
Oomycetes are pathogens responsible for many plant diseases over the world and the economical impact of their damage is quite important. Although these organisms show a mycelar growth, their biology is quite different from that of fungi. This makes them not easy to fight against and up to now no fungicide is able to stop an epidemy due to Oomycetes in a durable way. The particular biology of...
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Thèse de doctorat : Université de Fribourg, 2005 ; no 1471.
This PhD thesis focuses on the findings from Arbon-Bleiche 3, a Neolithic lacustrine village on the Southern shore of Lake Constance (Bodensee, Switzerland). From 1993 to 1995, 1100 m2 were excavated by the archaeological service of Thurgau (Leuzinger, 2000). The settlement was occupied during a very short period, fifteen years (3384-3370 BC) in the transitional period between Pfyn (3900- 3600...
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Thèse de doctorat : Université de Fribourg, 2001 ; no 1362.
Two different projects related to Atomic Physics are contained in the present Ph.D. thesis. The first project concerns the natural widths of atomic core levels whereas the second one deals with the double KL excitation of gaseous argon resulting from impact with monoenergetic photons. The first project itself is divided in two parts: the first one is an experimental study of the L1 to N5 atomic...
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