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Université de Fribourg

Evolution in group-structured populations can resolve the tragedy of the commons

Killingback, Timothy ; Bieri, Jonas ; Flatt, Thomas

In: Proceeding of the Royal Society, 2006, no. 273, p. 1477–1481

Public goods are the key features of all human societies and are also important in many animal societies. Collaborative hunting and collective defence are but two examples of public goods that have played a crucial role in the development of human societies and still play an important role in many animal societies. Public goods allow societies composed largely of cooperators to outperform...

Université de Fribourg

Comparing thyroid and insect hormone signaling

Flatt, Thomas ; Moroz, Leonid L. ; Tatar, Marc ; Heyland, Andreas

In: Integrative and Comparative Biology, 2006, vol. 46, no. 6, p. 777-794

Transitions between different states of development, physiology, and life history are typically mediated by hormones. In insects, metamorphosis and reproductive maturation are regulated by an interaction between the sesquiterpenoid juvenile hormone (JH) and the steroid 20-hydroxy-ecdysone (20E). In vertebrates and some marine invertebrates, the lipophilic thyroid hormones (THs) affect...

Université de Fribourg

Hormonal pleiotropy and the juvenile hormone regulation of Drosophila development and life history

Flatt, Thomas ; Tu, Meng-Ping ; Tatar, Marc

In: BioEssays, 2005, vol. 27, no. 10, p. 999-1010

Understandinghowtraits are integrated at the organismal level remains a fundamental problem at the interface of developmental and evolutionary biology. Hormones, regulatory signaling molecules that coordinate multiple developmental and physiological processes, are major determinants underlying phenotypic integration. The probably best example for this is the lipid-like juvenile hormone (JH) in...

Université de Fribourg

Effect of aging on thermal conductivity of fiber-reinforced aerogel composites: An X-ray tomography study

Iswara, Subramaniam ; Griffa, Michele ; Kaufmann, Rolf ; Beltran, Mario ; Huber, Lukas ; Brunner, Samuel ; Lattuada, Marco ; M.Koebel, Matthias ; Malfait, Wim J.

In: Microporous and Mesoporous Materials, 2019, vol. 278, p. 289–296

Silica aerogels display an ultra-low thermal conductivity (λ) and are used as thermal superinsulators. Here, we study the influence of aging and drying processes on the microstructure and thermal conductivity of fiber-reinforced silica aerogel composites. Glass wool-silica gel composites were aged for variable times, hydrophobized, and dried either at ambient pressure or from supercritical...

Université de Fribourg

Heating behavior of magnetic iron oxide nanoparticles at clinically relevant concentration

Lemal, Philipp ; Balog, Sandor ; Geers, Christoph ; Taladriz-Blanco, Patricia ; Palumbo, Andrea ; M.Hirt, Ann ; Rothen-Rutishauser, Barbara ; Petri-Fink, Alke

In: Journal of Magnetism and Magnetic Materials, 2019, vol. 474, p. 637–642

Magnetic hyperthermia for cancer treatment has gained significant attention in recent years, due to its biocompatibility of applied nanoparticles and the possibility for spatially localized heating in deep tissues. Clinical treatments use nanoparticle concentrations of 112 mg Fe/mL, while the concentrations experimental studies have addressed are considerably smaller, usually between 0.1...

Université de Fribourg

Emergence of nanoplastic in the environment and possible impact on human health

Lehner, Roman ; Weder, Christoph ; Petri-Fink, Alke ; Rothen-Rutishauser, Barbara

In: Environmental Science & Technology, 2019, vol. 53, no. 4, p. 1748–1765

On account of environmental concerns, the fate and adverse effects of plastics have attracted considerable interest in the past few years. Recent studies have indicated the potential for fragmentation of plastic materials into nanoparticles, i.e., “nanoplastics,” and their possible accumulation in the environment. Nanoparticles can show markedly different chemical and physical properties...

Université de Fribourg

Living long and well: prospects for a personalized approach to the medicine of ageing

Fuellen G. ; Schofield P. ; Flatt Thomas ; Schulz R.-J. ; Boege F. ; Kraft K. ; Rimbach G. ; Ibrahim S. ; Tietz A. ; Schmidt C. ; Köhling R. ; Simm A.

In: Gerontology, 2016, vol. 62, no. 4, p. 409–416

Research into ageing and its underlying molecular basis enables us to develop and implement targeted interventions to ameliorate or cure its consequences. However, the efficacy of interventions often differs widely between individuals, suggesting that populations should be stratified or even individualized. Large-scale cohort studies in humans, similar systematic studies in model organisms as...

Université de Fribourg

Similarities and differences in altitudinal versus latitudinal variation for morphological traits in Drosophila melanogaster

Klepsatel, Peter ; Gáliková, Martina ; Huber, Christian D. ; Flatt, Thomas

In: Evolution, 2014, vol. 68, no. 5, p. 1385–1398

Understanding how natural environments shape phenotypic variation is a major aim in evolutionary biology. Here, we have examined clinal, likely genetically based variation in morphology among 19 populations of the fruit fly (Drosophila melanogaster) from Africa and Europe, spanning a range from sea level to 3000 m altitude and including locations approximating the southern and northern range...

Université de Fribourg

Inference of chromosomal inversion dynamics from Pool-Seq data in natural and laboratory populations of Drosophila melanogaster

Kapun, Martin ; van Schalkwyk, Hester ; McAllister, Bryant ; Flatt, Thomas ; Schlötterer, Christian

In: Molecular Ecology, 2014, vol. 23, no. 7, p. 1813–1827

Sequencing of pools of individuals (Pool‐Seq) represents a reliable and cost‐effective approach for estimating genome‐wide SNP and transposable element insertion frequencies. However, Pool‐Seq does not provide direct information on haplotypes so that, for example, obtaining inversion frequencies has not been possible until now. Here, we have developed a new set of diagnostic marker...

Université de Fribourg

Variation in thermal performance and reaction norms among populations of Drosophila melanogaster

Klepsatel, Peter ; Gáliková, Martina ; De Maio, Nicola ; Huber, Christian D. ; Schlötterer, Christian ; Flatt, Thomas

In: Evolution, 2013, vol. 67, no. 12, p. 3573–3587

The major goal of evolutionary thermal biology is to understand how variation in temperature shapes phenotypic evolution. Comparing thermal reaction norms among populations from different thermal environments allows us to gain insights into the evolutionary mechanisms underlying thermal adaptation. Here, we have examined thermal adaptation in six wild populations of the fruit fly (Drosophila...