In: Evolution, 2004, vol. 58, no. 4, p. 757-767
Learning is thought to be adaptive in variable environments, whereas constant, predictable environments are supposed to favor unconditional, genetically fixed responses. A dichotomous view of behavior as either learned or innate ignores a potential evolutionary interaction between the learned and innate components of a behavioral response. We addressed this interaction in the context of...
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In: Ecology Letters, 2004, vol. 7, p. 1225-1241
Studies of local adaptation provide important insights into the power of natural selection relative to gene flow and other evolutionary forces. They are a paradigm for testing evolutionary hypotheses about traits favoured by particular environmental factors. This paper is an attempt to summarize the conceptual framework for local adaptation studies. We first review theoretical work relevant for...
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Thèse de doctorat : Université de Fribourg : 2003 ; no 1400.
Proper chromosome segregation is a crucial event for accurate cell division. Defects in chromosome segregation lead to genetic instability and aneuploidy and are correlated with cancer. The laboratory studies chromosome segregation in the budding yeast Saccharomyces cerevisiae. Since this process is highly conserved among eukaryotes, studies in yeast will provide fundamental understanding of this...
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Thèse de doctorat : Université de Fribourg : 2002 ; no 1388.
The biocompatibility of materials in implant or biosensor fields strongly depends on first interactions occurring between a given surface and a biological environment. It is well-known that a living body brought into contact with a surface will induce protein adsorption, which creates the interface, on which proteins or cells will adsorb. The interactions can be influenced by modifying the...
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Thèse de doctorat : Université de Fribourg : 2000 ; no 1302.
This thesis describes the development and the applications of four wave mixing techniques (Transient Grating (TG), Coherent Anti-Stokes Raman Scattering (CARS) and Transient Dichroism (TD)), to investigate processes taking place in the pico- and femtosecond time scales. In the first part of the work, the TG technique is described using both the holography and the nonlinear optics formalisms. The...
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Thèse de doctorat : Université de Fribourg : 2000 ; Nr. 1328.
Human gene therapy can be defined as the directed transfer of exogenous genes or other nucleotide sequences into somatic cells, for the purpose of preventing, correcting or healing various diseases. This novel approach to the therapy of human disorders is based on the realization that many previous medical treatments have usually been directed at the consequences of causative defects or at...
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Thèse de doctorat : Université de Fribourg : 2000 ; no 1303.
Starting from the El Farol's bar problem, we introduce the minority game, an extremely simple model of competition between adaptive agents. We study its properties, and find that it displays a phase transition with symmetry breaking. An adequate mathematical formalism is introduced and reveals the spin glass nature of the model. We prove that available information is a Lyapunov function for this...
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Thèse de doctorat : Université de Fribourg : 2000 ; Nr. 1326.
The study of nuclear structure is one of the research domains in nuclear physics which have known an important development. It has asked a great effort for the experimenters as well as the theoreticians to study in detail the nuclear many-body problem. In the framework of this thesis, we have tested several nuclear models for two nuclei: 110Cd and 114Te. This choice has not been made at random....
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Thèse de doctorat : Université de Fribourg : 2003 ; 1403.
La plupart des animaux, invertébrés inclus, ont la capacité de modifier leur comportement à la suite d'expériences, ils sont capables d'apprendre. Leur capacité d'apprentissage est elle-même un produit de l'évolution et le degré de modification d'un comportement par l'apprentissage varie selon les espèces et selon le comportement considéré. Pour un biologiste de l'évolution ceci...
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Thèse de doctorat : Université de Fribourg : 2002 ; 1374.
Das Problem wechselwirkender Elektronen in zwei Dimensionen ist spätestens seit der Entdeckung der Hoch-Temperatur-Supraleitung von grosser Aktualität und Gegenstand intensiver Forschungstätigkeit. In der vorliegenden Arbeit wird ein erweitertes Hubbard-Modell auf einem Quadratgitter untersucht. Obwohl man weiss, dass die Leitungselektronen in den Kupraten relativ stark miteinander...
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