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Université de Fribourg

A transgenic dTph1 insertional mutagenesis system for forward genetics in mycorrhizal phosphate transport of Petunia

Wegmüller, Sarah ; Svistoonoff, Sergio ; Reinhardt, Didier ; Stuurman, Jeroen ; Amrhein, Nikolaus ; Bucher, Marcel

In: The Plant Journal, 2008, vol. 54, no. 6, p. 1115 - 1127

The active endogenous dTph1 system of the Petunia hybrida mutator line W138 has been used in several forward-genetic mutant screens that were based on visible phenotypes such as flower morphology and color. In contrast, defective symbiotic phosphate (Pi) transport in mycorrhizal roots of Petunia is a hidden molecular phenotype as the symbiosis between plant roots and fungi takes place...

Université de Fribourg

Chromosome numbers and mode of reproduction in Picris hieracioides s.l. (Asteraceae), with notes on some other Picris taxa

Slovák, Marek ; Šingliarová, Barbora ; Mráz, Patrik

In: Nordic Journal of Botany, 2007, vol. 25, no. 3-4, p. 238 - 244

Chromosome numbers for 88 plants of Picris hieracioides s.l. originating from 32 localities from Austria, Andorra, Croatia, France, Germany, Hungary, Italy, Slovakia and Spain are reported. All analysed plants were diploid, with 2n=2x=10. In addition to P. hieracioides s.l., we also found diploidy (2n=2x=10) in P. nuristanica from Kirgizia and P. japonica from Japan. Our data confirmed previously...

Université de Fribourg

How is the invasive gorse Ulex europaeus pollinated during winter? A lesson from its native range

Bowman, Gillianne ; Tarayre, Michèle ; Atlan, Anne

In: Plant Ecology, 2008, vol. 197, no. 2, p. 197-206

Many examples of plant-insect interactions have shown that selection from herbivores can act on flowering and fruiting phenology. In Ulex europaeus (Fabaceae), escaping seed predation resulted in extended, but variable flowering periods, with some plants flowering from autumn until spring and others flowering only in spring. The present study aims at understanding how gorses can have a high...

Université de Fribourg

Immune system based intrusion detection system

Ehret, Christoph ; Ultes-Nitsche, Ulrich

In: Innovative Minds (Information Systems Security Association - ISSA 2008), Johannesburg, South Africa, July 2008, 2008, p. -

The threats and intrusions in IT systems can basically be compared to human diseases with the difference that the human body has an effective way to deal with them, what still need to be designed for IT systems. The human immune system (HIS) can detect and defend against yet unseen intruders, is distributed, adaptive and multilayered to name only a few of its features. Our immune system...

Université de Fribourg

Superconductivity and antiferromagnetism in the two-dimensional Hubbard model

Eichenberger, David ; Baeriswyl, Dionys (Dir.)

Thèse de doctorat : Université de Fribourg, 2008.

En dépit de son apparente simplicité et bien qu’il ait déjà été intensivement étudié dans des contextes très variés, le modèle de Hubbard bidimensionnel est encore très loin d’avoir livré tous ses mystères. En particulier lorsqu’il décrit une interaction moyenne à fortement répulsive, c’est-à-dire un régime mal adapté aux méthodes perturbatives, son état fondamental...

Université de Fribourg

Modellierung, Entwicklung und Nutzung eines Data Warehouse für medizinische Communication Centers

Ionas, Andreea ; Meier, Andreas (Dir.) ; Teufel, Stephanie (Codir.)

Thèse de doctorat : Université de Fribourg, 2008.

Das heutige Gesundheitssystem wird von den vielen Akteuren, den komplexen Beziehungen, den anspruchsvollen Patienten sowie dem veränderten Gesundheitsbewusstsein geprägt. Medizinische Communication Centers können als zentraler Kontaktpunkt zwischen Gesundheitssystem und Bevölkerung dienen. Durch die verschiedenen angebotenen medizinischen Dienstleistungen und die permanente Erreichbarkeit...

Université de Fribourg

pyVib, a computer program for the analysis of infrared and Raman optical activity

Zerara, Mohamed

In: Journal of Computational Chemistry, 2008, vol. 29, no. 2, p. 306 - 311

A new program called pyVib has been developed as a tool for the analysis of Gaussian (Gaussian 03, Gaussian Inc., Pittsburgh, PA) outputs of vibrational absorption (IR), Raman as well as vibrational optical activity (VOA) spectra calculations. This program has been designed to help the computational chemistry practitioner in the task of analyzing and visualizing molecular vibrations and cross...

Université de Fribourg

Step-by-step random walk network with power-law clique-degree distribution

Han-Xin, Yang ; Bing-Hong, Wang ; Jian-Guo, Liu ; Xiao-Pu, Han ; Tao, Zhou

In: Chinese Physics Letters, 2008, vol. 25, no. 7, p. 2718-2720

We propose a simple mechanism for generating scale-free networks with degree exponent γ = 3, where the new node is connected to the existing nodes by step-by-step random walk. It is found that the clique-degree distribution based on our model obeys a power-law form, which is in agreement with the recently empirical evidences. In addition, our model displays the small-world effect and the...