The Environment and Directed Technical Change: Comment

This paper discusses the growth model with environmental constraints recently presented in (Acemoglu et al., 2011) which focuses on the redirection of technical change by climate policies with research subsidies and a carbon tax. First, Acemoglu et al.'s model and chosen parameters yield numerical results that do not support the conclusion that ambitious climate policies can be conducted “without sacrificing (much or any) long-run growth”. Second, they select unrealistic key parameters for carbon sinks and elasticity of substitution. We find that more realistic parameters lead to very different results. Third, the model leads to an unrealistic conclusion when used to analyse endogenous growth, suggesting specification problems.Technological Change, Endogenous Growth, Climate, Energy Substitutability

Transferts culturels et déclinaisons de la pédagogie européenne: le cas franco-romand au travers de l'itinéraire d'Alexandre Daguet (1816-1894)

Cette thèse vise à réévaluer la circulation des savoirs pédagogiques dans l’espace francosuisse. Méthodologiquement, nous nous proposons d’insister sur les modalités de passage de ces savoirs d’un contexte culturel à l’autre, en étudiant les acteurs, les vecteurs, ainsi que les inévitables transformations sémantiques qui accompagnent nécessairement ces échanges transnationaux. Cette recherche, articulée sous la forme d’une Gesellschaftsbiographie, prend pour guide le théoricien des idées éducatives, Alexandre Daguet (1816-1894). Il s’agit d’éclairer son rôle de médiateur privilégié dans le transfert de savoirs pédagogiques entre la Suisse romande et la France, en étudiant notamment son rôle de passeur via la revue L’Éducateur. Bien qu’il ait décliné l’appel de Ferdinand Buisson à édifier avec lui une « oeuvre internationale d’éducation », il n’en a pas pour le moins joué un rôle de « courtier » dans la diffusion de savoirs spécifiques, véhiculés notamment par les proscrits français réfugiés en Suisse romande dès 1852. Cette thèse permet de souligner comment les savoirs pédagogiques européens, élaborés de manière collective, sont diversement déclinés selon des spécificités locales. Dans ce sens, il s’agit de montrer qu’à mesure que les identités se solidifient, les spécificités nationales sont de plus en plus exaltées lors des Expositions universelles et les « exotismes » bientôt dévalorisés, voire même dissimulés au profit d’un certain génie national. Cette recherche souhaite donc contextualiser cette apparence trompeuse de Sonderfälle, pour mettre davantage de relief dans la construction collective d’une pédagogie européenne métissée. Mots clés : Alexandre Daguet, Suisse, transferts culturels, transformation sémantique, circulation des savoirs, histoire de la pédagogie, Ferdinand Buisson, Troisième RépubliqueThis thesis seeks to reassess the way in which pedagogical knowledge circulated between France and Switzerland. In terms of method, we have chosen to focus on the way in which this knowledge passed from one cultural context to another by studying the related actors and vectors, as well as the inevitable semantic transformations which, of necessity, accompany transnational exchanges of this nature. The research takes the form of a Gesellschaftsbiographie, with a guide in the person of educational theorist Alexandre Daguet (1816-1894). It aims to shed light on his role as a key mediator in the transfer of pedagogical expertise between French-speaking Switzerland and France, with a special emphasis on the way he used the review L’Éducateur to take this knowledge across borders. Although Daguet turned down the proposal by Ferdinand Buisson to work with the latter to create an “international treatise on education”, he nevertheless acted as a ‘broker’ in the trade of specific knowledge, passed on in particular by the French political exiles that took refuge in French-speaking Switzerland from 1852 onwards. The thesis also highlights the way in which European pedagogical knowledge, developed collectively, was applied in a variety of ways depending on local particularities. The issue here is to show the way in which, as identities became more firmly established, distinctive national features were increasingly honoured at Universal Expositions, while the various forms of “exoticism” soon fell out of favour, sometimes even to the point of being concealed in favour of national genius. This research therefore seeks to contextualise the deceptive semblance of Sonderfälle and provide a clearer picture of the collective emergence of a multifaceted European pedagogy. Key words : Alexandre Daguet, Switzerland, cultural transfer, semantic transformation, circulation of knowledge, history of pedagogy, Ferdinand Buisson, French Third Republi

Ultrafast light-induced response of photoactive yellow protein chromophore analogues

The fluorescence decays of several analogues of the photoactive yellow protein (PYP) chromophore in aqueous solution have been measured by femtosecond fluorescence up-conversion and the corresponding time-resolved fluorescence spectra have been reconstructed. The native chromophore of PYP is a thioester derivative of p-coumaric acid in its trans deprotonated form. Fluorescence kinetics are reported for a thioester phenyl analogue and for two analogues where the thioester group has been changed to amide and carboxylate groups. The kinetics are compared to those we previously reported for the analogues bearing ketone and ester groups. The fluorescence decays of the full series are found to lie in the 1–10 ps range depending on the electron-acceptor character of the substituent, in good agreement with the excited-state relaxation kinetics extracted from transient absorption measurements. Steady-state photolysis is also examined and found to depend strongly on the nature of the substituent. While it has been shown that the ultrafast light-induced response of the chromophore in PYP is controlled by the properties of the protein nanospace, the present results demonstrate that, in solution, the relaxation dynamics and pathway of the chromophore is controlled by its electron donor–acceptor structure: structures of stronger electron donor–acceptor character lead to faster decays and less photoisomerisation