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Université de Fribourg

Enigmatic dinosaur precursors bridge the gap to the origin of Pterosauria

Ezcurra, Martín D. ; Nesbitt, Sterling J. ; Bronzati, Mario ; Vecchia, Fabio Marco Dalla ; Agnolin, Federico L. ; Benson, Roger B. J. ; Egli, Federico Brissón ; Cabreira, Sergio F. ; Evers, Serjoscha W. ; Gentil, Adriel R. ; Irmis, Randall B. ; Martinelli, Agustín G. ; Novas, Fernando E. ; Silva, Lúcio Roberto da ; Smith, Nathan D. ; Stocker, Michelle R. ; Turner, Alan H. ; Langer, Max C.

In: Nature, 2020, vol. 588, no. 2020-7838, p. 445–449

Pterosaurs were the first vertebrates to evolve powered flight1 and comprised one of the main evolutionary radiations in terrestrial ecosystems of the Mesozoic era (approximately 252–66 million years ago), but their origin has remained an unresolved enigma in palaeontology since the nineteenth century2,3,4. These flying reptiles have been hypothesized to be the close relatives of a wide...

Université de Fribourg

Birds have peramorphic skulls, too: anatomical network analyses reveal oppositional heterochronies in avian skull evolution

Plateau, Olivia ; Foth, Christian

In: Communications Biology, 2020, vol. 3, no. 1, p. 195

In contrast to the vast majority of reptiles, the skulls of adult crown birds are characterized by a high degree of integration due to bone fusion, e.g., an ontogenetic event generating a net reduction in the number of bones. To understand this process in an evolutionary context, we investigate postnatal ontogenetic changes in the skulls of crown bird and non-avian theropods using anatomical...

Université de Fribourg

Simple assessment of height and length of flight in complex gymnastic skills: validity and reliability of a two-dimensional video analysis method

Schärer, Christoph ; Siebenthal, Luca von ; Lomax, Ishbel ; Gross, Micah ; Taube, Wolfgang ; Hübner, Klaus

In: Applied Sciences, 2019, vol. 9, no. 19, p. 3975

In artistic gymnastics, the possibility of using 2D video analysis to measure the peak height (hpeak) and length of flight (L) during routine training in order to monitor the execution and development of difficult elements is intriguing. However, the validity and reliability of such measurements remain unclear. Therefore, in this study, the hpeak and L of 38 vaults, performed by top-level...

Università della Svizzera italiana

Optimization of anchor nodes placement in wireless localization networks

Balac, Katarina ; Malek, Miroslaw (Dir.) ; Prevostini, Mauro (Codir.)

Thèse de doctorat : Università della Svizzera italiana, 2019 ; 2019INFO009.

This work focuses on optimizing node placement for time-of-flight-based wireless localization networks. Main motivation are critical safety applications. The first part of my thesis is an experimental study on in-tunnel vehicle localization. In- tunnel localization of vehicles is crucial for emergency management, especially for large trucks transporting dangerous goods such as inflammable...

Université de Fribourg

Solution Methods for a Scheduling Problem with Incompatibility and Precedence Constraints

Meuwly, François-Xavier ; Ries, Bernard ; Zufferey, Nicolas

In: Algorithmic Operations Research, 2010, vol. 5, p. 75-85

Consider a project which consists in a set of operations to be performed, assuming the processing time of each operation is at most one time period. In this project, precedence and incompatibility constraints between operations have to be satisfied. The goal is to assign a time period to each operation while minimizing the duration of the whole project and while taking into account all the...

Université de Fribourg

The faster, the better? Relationships between run-up speed, the degree of difficulty (D-score), height and length of flight on vault in artistic gymnastics

Schärer, Christoph ; Lehmann, Thomas ; Naundorf, Falk ; Taube, Wolfgang ; Hübner, Klaus

In: PLOS ONE, 2019, vol. 14, no. 3, p. e0213310

On vault in artistic gymnastics, a high run-up speed is thought to be important when performing difficult vaults. To test this assumption in a large cohort of elite athletes, we calculated the correlations between the run-up speed, scores, height and length of flight for handspring-, Tsukahara- and Yurchenko-style vaults and compared the performances of male and female elite and junior...

Université de Fribourg

Adaptation to fluctuating environments in a selection experiment with Drosophila melanogaster

Kubrak, Olga I. ; Nylin, Sören ; Flatt, Thomas ; Nässel, Dick R. ; Leimar, Olof

In: Ecology and Evolution, 2017, vol. 7, no. 11, p. 3796–3807

A fundamental question in life‐history evolution is how organisms cope with fluctuating environments, including variation between stressful and benign conditions. For short‐ lived organisms, environments commonly vary between generations. Using a novel experimental design, we exposed wild‐derived Drosophila melanogaster to three different selection regimes: one where generations...