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Résumé Introduction La prise de conscience des effets du comportement humain sur l’environnement a accru l’importance de l’étude des déterminants des comportements pro-environnementaux. Les outils de mesures validés et spécifiques à ce domaine sont peu nombreux. Objectif Cet article a pour but de valider en langue française l’ Environmental Attitudes Inventory, brief version , développé par Milfont et Duckitt (2010). Le choix de traduire cette échelle s’est imposé de par ses qualités psychométriques, sa bonne prédiction du comportement, sa validité théorique, ainsi que son utilisation dans des pays variés. En plus de la version à 24 items, nous avons testé une version réduite à 12 items. Méthode Trois échantillons ont été utilisés pour étudier la structure de l’IAE, son réseau nomologique, sa fidélité test–retest et sa validité prédictive. Résultats L’IAE-24 a des propriétés psychométriques similaires à la version originale, autant pour un modèle à deux facteurs (préservation et utilisation) que pour un modèle à un facteur. L’IAE-12 est satisfaisante au niveau de la consistance interne à condition d’utiliser un modèle à un facteur. Le réseau nomologique de l’IAE-24 n’est pas complètement identique à celui de la version originale. Les différences sont expliquées par des inconsistances dans la littérature et par des choix d’outils différents. La validité prédictive de la version française (24 et 12 items) est très satisfaisante, tout comme la fidélité test–retest. Conclusion L’IAE est désormais disponible en français avec des qualités psychométriques satisfaisantes. Introduction Climate change has made it necessary to develop valid tools for studying pro-environmental behaviors. Objectives The present study assessed the validity of the French translation of the brief version of Milfont and Duckitt's (2010) Environmental Attitudes Inventory. We chose this scale for its psychometric properties, its ability to predict behaviors, its theoretical foundations, and its use in many countries. In addition to the translation, we tested a shortened, 12-item version of the scale. Method Three samples were used to study the structure of the IAE, its nomological network, its test–retest fidelity, and its predictive validity. Results IAE-24 has similar psychometric properties to the original version, for both one-factor and two-factor models (preservation and utilization dimensions). IAE-12 has satisfactory internal consistency if the one-factor model is used. The nomological network of IAE-24 is not totally identical to the original version. Differences can be ascribed to inconsistencies in the literature and the use of different scales. Both IAE-24 and IAE-12 have very satisfactory predictive validity and test–retest reliability. Conclusion The French version of the IAE has satisfactory psychometric properties. [ABSTRACT FROM AUTHOR]

Abstract: 3-Cyanopyridine (3-cnp) modulates via inactivation and/or inhibition, the amidase activity of the resting cells of Microbacterium imperiale CBS 489-74 which contained an in situ nitrile hydratase-amidase (NHase/AMase) cascade system suitable for catalyzing the bio-production of nicotinic acid form 3-cnp. The combined effect of 3-cnp concentration and temperature is investigated on the sole AMase activity by selectively inactivating the NHase activity. The study was performed in continuous stirred membrane reactors (CSMRs) fed with 100mM nicotinamide solutions containing 25–200mM 3-cnp at various temperatures. At 25–40°C, the inactivation constant is negligible, even at high 3-cnp concentration, and the decrease in AMase activity is reversible. At 50°C, a synergistic effect of temperature and 3-cnp inactivates AMase irreversibly, thus preventing a high yield being reached. [Copyright &y& Elsevier]

Abstract: High yields of nicotinic acid from 3-cyanopyridine bioconversion were obtained by exploiting the in situ nitrile hydratase–amidase enzymatic cascade system of Microbacterium imperiale CBS 498-74. Experiments were carried out in continuously stirred tank UF-membrane bioreactors (CSMRs) arranged in series. This reactor configuration enables both enzymes, involved in the cascade reaction, to work with optimized kinetics, without any purification, exploiting their differing temperature dependences. To this end, the first CSMR, optimized for the properties of the NHase, was operated (i) at low temperature (5°C), limiting inactivation of the more fragile enzyme, nitrile hydratase, (ii) with a high residence time (24h) to overcome reaction rate limitation. The second CSMR, optimized for the properties of the AMase, was operated (i) at a higher temperature (50°C), (ii) with a lower residence time (6h), and (iii) with a lower substrate (3-cyanopyridine) concentration to control excess substrate inhibition. The appropriate choice of operational conditions enabled total conversion of 3-cyanpyridine (up to 200mM) into nicotinic acid to be achieved at steady-state and for long periods. Higher substrate concentrations required two CSMRs optimized for the properties of the NHase arranged in series to drive the first reaction to completion. [Copyright &y& Elsevier]

Abstract: The bioconversion of 3-cyanopyridine using the in situ nitrile hydratase–amidase cascade system of resting Microbacterium imperiale CBS 498-74 cells was investigated in an ultrafiltration-membrane reactor, operated in either batch or continuous mode. The effects of operating conditions such as the amount of biocatalyst, substrate concentration, substrate feeding rate, mean residence time, and enzyme-to-substrate ratio, were investigated with the aim of achieving almost 100% substrate conversion and high reactor productivity. As a result, it was found that the NHase–AMase cascade system could be adequately exploited in a continuous reactor configuration. The differing temperature dependence of nitrile hydratase and amidase kinetics enabled the operational parameters to be module d to ensure (i) nitrile hydratase operational stability (at 5°C), and (ii) 100% conversion of 3-cyanopyridine into nicotinic acid, or, alternatively, (iii) enrichment of the effluent stream with the intermediate nicotinamide (up to 80% conversion). It was possible to select operating conditions that allowed long periods of operation (at least 100h) at a constant flow-rate without enzyme activity loss. [Copyright &y& Elsevier]