Université de Neuchâtel

Badge Size Reflects Sperm Oxidative Status within Social Groups in the House Sparrow Passer domesticus

Rojas Mora, Alfonso ; Meniri, Magali ; Glauser, Gaëtan ; Vallat, Armelle ; Helfenstein, Fabrice

In: Frontiers in Ecology and Evolution, 2016, vol. 4, no. 67, p. 1-10

The phenotype-linked fertility hypothesis proposes that male ornaments reflect male fertility. Male ornaments could honestly signal sperm quality due to the high susceptibility of sperm to free radicals on the one hand and the negative impact of oxidative stress on ornament elaboration on the other hand. Thus, only males with superior antioxidant defences could bear the cost of more elaborated...

Université de Neuchâtel

Intra- and interspecific challenges modulate cortisol but not androgen levels in a year-round territorial damselfish

Ros, Albert F. H ; Vullioud, Philippe ; Bruintjes, Rick ; Vallat, Armelle ; Bshary, Redouan

In: The Journal of Experimental Biology, 2014, vol. 217, no. 10, p. 1768-1774

Interactions between individuals of different species are commonplace in animal communities. Some behaviors displayed during these interspecific social interactions may be very similar to those displayed during intraspecific social interactions. However, whether functional analogies between intra- and interspecific behaviors translate at the proximate level into an overlap in their underlying...

Université de Neuchâtel

Highly selective C = C bond hydrogenation in α,β-unsaturated ketones catalyzed by hectorite-supported ruthenium nanoparticles

Khan, Farooq-Ahmad ; Vallat, Armelle ; Süss-Fink, Georg

In: Journal of Molecular Catalysis A: Chemical, 2010, vol. 355, p. 168–173

Metallic ruthenium nanoparticles intercalated in hectorite (particle size ∼7 nm) were found to catalyze the specific hydrogenation (conversion 100%, selectivity > 99.9%) of the carbon–carbon double bond in α,β-unsaturated ketones such as 3-buten-2-one, 3-penten-2-one, 4-methyl-3-penten-2-one. The catalytic turnovers range from 765 to 91,800, the reaction conditions being very mild...

Université de Neuchâtel

Highly selective low-temperature hydrogenation of furfuryl alcohol to tetrahydrofurfuryl alcohol catalysed by hectorite-supported ruthenium nanoparticles

Khan, Farooq-Ahmad ; Vallat, Armelle ; Süss-Fink, Georg

In: Catalysis Communications, 2011, vol. 12, no. 15, p. 1428–1431

Metallic ruthenium nanoparticles intercalated in hectorite (particle size ~ 4 nm) were found to catalyse the hydrogenation of furfuryl acohol to give tetrahydrofurfuryl alcohol in methanolic solution under mild conditions. The best results were obtained at 40 °C under a hydrogen pressure of 20 bar (conversion 100%, selectivity > 99%). After a total turnover number of 1423, the hectorite...