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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

SEM study of black, blue, violet and yellow inglaze colours of the oldest Swiss tin‐opacified stove tiles (c .1450– c .1512, canton Bern)*

Maggetti, Marino

In: Archaeometry, 2020, p. arcm.12638

The ceramic colours of eight late medieval to early Renaissance stove tiles were studied by scanning electron microscopy‐backscattered electron (SEM‐BSE) images and SEM with energy‐dispersive spectroscopy (SEM‐EDS). Microstructural observations and chemical compositions of these colours give some insight into the colouring agents and techniques used by the potters. All decorations...

Université de Fribourg

Anatomic analysis of the internal and external aspects of the pterion

Uz, Aysun ; Korkmaz, Ali Can ; Filgueira, Luis ; Guner, Mehmet Ali ; Tubbs, Richard Shane ; Demirciler, Ayse Karatas

In: World Neurosurgery, 2020, vol. 137, p. 84–88

Objective: The pterion is an H-shaped suture complex. This study's goal was to determine the location of its external and internal surfaces and extension and emphasize and discuss its surgical importance.Methods: Fifty dried adult human skulls were obtained from the Department of Anatomy. A 2-mm drill bit was placed externally over the pterion, and the pterion was drilled through the bone...

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

Feeding biomechanics suggests progressive correlation of skull architecture and neck evolution in turtles

Ferreira, Gabriel S. ; Lautenschlager, Stephan ; Evers, Serjoscha W. ; Pfaff, Cathrin ; Kriwet, Jürgen ; Raselli, Irena ; Werneburg, Ingmar

In: Scientific Reports, 2020, vol. 10, p. 5505

The origin of turtles is one of the most long-lasting debates in evolutionary research. During their evolution, a series of modifications changed their relatively kinetic and anapsid skull into an elongated akinetic structure with a unique pulley system redirecting jaw adductor musculature. These modifications were thought to be strongly correlated to functional adaptations, especially to bite...

Università della Svizzera italiana

The C-terminal domain of TPX2 is made of alpha-helical tandem repeats

Sanchez-Pulido, Luis ; Perez, Laurent ; Kuhn, Steffen ; Vernos, Isabelle ; Andrade-Navarro, Miguel A.

In: BMC structural biology, 2016, vol. 16, p. 17

Background: TPX2 (Targeting Protein for Xklp2) is essential for spindle assembly, activation of the mitotic kinase Aurora A and for triggering microtubule nucleation. Homologs of TPX2 in Chordata and plants were previously identified. Currently, proteins of the TPX2 family have little structural information and only small parts are covered by defined protein domains. Methods: We have used ...

Consortium of Swiss Academic Libraries

The SLC34 family of sodium-dependent phosphate transporters

Wagner, Carsten ; Hernando, Nati ; Forster, Ian ; Biber, Jürg

In: Pflügers Archiv - European Journal of Physiology, 2014, vol. 466, no. 1, p. 139-153