University of Fribourg

About: University of Fribourg is a education organization based out in Fribourg, Freiburg, Switzerland. It is known for research contribution in the topics: Population & Context (language use). The organization has 6040 authors who have published 14975 publications receiving 542500 citations. The organization is also known as: UNIFR & Universität Freiburg.

Admixture facilitates adaptation from standing variation in the European aspen (Populus tremula L.), a widespread forest tree

Abstract: Adaptation to new environments can start from new mutations or from standing variation already present in natural populations. Whether admixture constrains or facilitates adaptation from standing variation is largely unknown, especially in ecological keystone or foundation species. We examined patterns of neutral and adaptive population divergence in Populus tremula L., a widespread forest tree, using mapped molecular genetic markers. We detected the genetic signature of postglacial admixture between a Western and an Eastern lineage of P. tremula in Scandinavia, an area suspected to represent a zone of postglacial contact for many species of animals and plants. Stringent divergence-based neutrality tests provided clear indications for locally varying selection at the European scale. Six of 12 polymorphisms under selection were located less than 1 kb away from the nearest gene predicted by the Populus trichocarpa genome sequence. Few of these loci exhibited a signature of 'selective sweeps' in diversity-based tests, which is to be expected if adaptation occurs primarily from standing variation. In Scandinavia, admixture explained genomic patterns of ancestry and the nature of clinal variation and strength of selection for bud set, a phenological trait of great adaptive significance in temperate trees, measured in a common garden trial. Our data provide a hitherto missing direct link between past range shifts because of climatic oscillations, and levels of standing variation currently available for selection and adaptation in a terrestrial foundation species.

Satellites and large doping and temperature dependence of electronic properties in hole-doped BaFe2As2

Abstract: An approach to first-principles simulations that incorporates dynamically screened Coulomb interactions between iron d electrons enables the low-energy electronic structure and angle-resolved photoemission spectroscopy spectra of iron-based superconductors to be modelled with unprecedented accuracy.

Quantitative modeling of laser speckle imaging.

Abstract: We have analyzed the image formation and dynamic properties in laser speckle imaging (LSI) both experimentally and with Monte Carlo simulation. We show for the case of a liquid inclusion that the spatial resolution and the signal itself are both significantly affected by scattering from the turbid environment. Multiple scattering leads to blurring of the dynamic inhomogeneity as detected by LSI. The presence of a nonfluctuating component of scattered light results in the significant increase in the measured image contrast and complicates the estimation of the relaxation time. We present a refined processing scheme that allows a correct estimation of the relaxation time from LSI data.

Building a smart hospital using RFID technologies

Abstract: Technologies of identiflcation by radio frequencies (RFID) experience a fast development and healthcare is predicted to be one of its major growth areas. After brie∞y introducing the common terminology of the RFID fleld and its current standards, this paper describes how this emerging technology can be used to build a smart hospital. Indeed, used in combination with mobile devices in eHealth applications, RFID helps optimizing business processes in healthcare and improve patient safety. The second part of this article shows how to use an assets tracking application, called the RFIDLo- cator, to improve the quality of the hospital services. We developed the RFIDLocator to support the high requirements for scalability and reliability one can expect for such an application. An overview of its distributed software architecture is given. A short cookbook presents the required steps for its conflguration to the concrete case of the hospital. Some critical remarks about RFID technology, the important questions it raises and the barriers it has to overcome to be fully integrated in eHealth applications conclude this paper.