Escherichia coli as a potential hydrocarbon conversion microorganism. Oxidation of aliphatic and aromatic compounds by recombinant E. coli in two-liquid phase (aqueous-organic) systems

The increased interest in the study of hydrocarbon utilizing microorganisms in recent years has been stimulated by the possibility of using their monooxygenases in the selective oxidation of aliphatic and aromatic compounds. As an example, long chain (>C16) n-alkanes are converted to dicarboxylic acids by yeast. This type of bioconversion is useful because the regioselective and stereospecific introduction of oxygen into unactivated organic substrates by classical synthetic chemistry remains very difficult. Zie: General Conclusion

Honey-copy : a concept and prototype of a generic honeypot system

In this paper, we present Honey-Copy, a concept and prototype for a honeypot system that can pinpoint modifications caused by attacks or intrusion for any honeypot. To achieve this, we track modifications without having to install any additional tools on them. We make use of cloning to identify whether or not a modification has been caused by the honeypot itself or an attacker or intruder. We briefly present our initial prototype and discuss the challenges to be solved toward a more complete and feature rich version of our prototype

Steroid substrate-induced epimerase mechanism in the active site of the human 11β-hydroxysteroid dehydrogenase type 1

Cytochrome P4507B1 7[alpha]-hydroxylates dehydroepiandrosterone (DHEA), epiandrosterone (EpiA) and 5[alpha]-androstane-3[beta],17[beta]-diol (Adiol). 11[beta]-Hydroxysteroid dehydrogenase type 1 (11[beta]-HSD1) interconverts 7[alpha]- and 7[beta]- forms. Whether the inter-conversion proceeds through oxido-reductive steps or epimerase activity is investigated. Experiments using ^3^H-labeled 7[beta]-hydroxy-DHEA, 7[beta]-hydroxy-EpiA and 7[beta]-hydroxy-Adiol show the ^3^H-label to accumulate in 7-oxo-DHEA trap but neither in 7-oxo-EpiA nor 7-oxo-Adiol traps. Computed models of 7-oxygenated steroids dock in the active site of 11[beta]-HSD1 either in a flipped or turned form relative to cortisone and cortisol. 7-Oxo-steroid reduction in 7[alpha]- or 7[beta]-hydroxylated derivatives results from either turned or flipped forms. 11[beta]-HSD1 incubation in H~2~^18^O medium with each 7-hydroxysteroid did not incorporate ^18^O in 7-hydroxylated derivatives of EpiA and Adiol independently of the cofactor used. Thus oxido-reductive steps apply for the interconversion of 7[alpha]- and 7[beta]-hydroxy-DHEA through 7-oxo-DHEA. Epimerisation may proceed on the 7-hydroxylated derivatives of EpiA and Adiol through a mechanism involving the cofactor and Ser170

La fin d'une étrange lacune de la sociologie des mobilisations:L'étude par sondage des manifestants : fondements théoriques et solutions techniques

Si les formes et les ressorts de l'action collective commencent à être mieux connus, les individus qui manifestent — acteurs des démonstrations de rue — n'ont guère fait l'objet d'études centrées sur les modalités du passage à l'acte. Depuis Barnes et Kaase, il existe de solides études par sondage de la propension des individus à manifester, mais ces études renseignent sur les représentations, et notamment sur la perception de la légitimité de l'action collective, et sur les dispositions à agir, et non sur les comportements effectifs. La plupart des travaux classiques sur la manifestation prennent comme unité d'analyse ces événements que sont les manifestations et constituent des corpus plus ou moins étendus mais toujours riches en informations. Mais d'une part, les conclusions qui s'en dégagent sont le plus souvent non compatibles avec celles issues des études sur la propension à manifester. D'autre part, ces travaux n'aident guère à élucider les mécanismes de la participation des individus à l'action. La solution proposée pour mettre fin à cette étrange lacune de la sociologie des mobilisations est le recours au sondage effectué pendant les manifestations. Mais cette méthode, qui n'a que de rares précédents, soulève des difficultés techniques spécifiques. Trois sondages dans des manifestations effectués à Paris entre février et mai 1994 ont permis d'apporter à ces difficultés des solutions qui font l'objet d'un exposé détaillé. L'apparence antinomie entre cette méthode par construction individualisante qu'est le sondage d'opinion et l'objet par nature collectif (la manifestation de rue) auquel on l'applique ne doit donc plus être considérée comme un obstacle.While the forms and springs of collective action are beginning to be better known, the individuals who demonstrate — the actors in street demonstrations — have not been subjected to studies centered on the modes of the move to action. Since Barnes and Kaase, we have serious survey studies of the propensity of individuals to demonstrate, but they provide data about representations, and in particular on the perception of the legitimacy of collective action and on the willingness to act, not on actual behavior. Most classic works on demonstrations take these as the units of analysis and build up more or less extensive data sets, always rich in information. But on the one hand, their conclusions are often incompatible with those of studies on the propensity to demonstrate. On the other hand, such research does not contribute much to elucidating the mechanisms of individual participation in demonstrations. The solution suggested in order to remedy this strange gap in the sociology of mobilizations is to take sample surveys during demonstrations. Rarely used, this procedure raises specific technical difficulties. Three polls taken during demons-trations in Paris between February and May 1994 provide solutions to these problems, which are here discussed at length. The apparent antinomy between a method of individualizing construction — the opinion poll — and an object of a collective nature — the street demonstration — to which it is applied must therefore no longer be considered an obstacle

Sizing of an Electric Power Steering system on dynamic and energetic criteria

International audienceThis paper presents the methodology to size a mechatronic system on dynamic and energetic criteria. The methodology is based on the establishment of the inverse model from the bond graph representation of the system by using the bicausality concept. By means of an automotive example, we illustrate the methodology and we present a solution to extend it to more complex problem

Energy Consumption and Performance of IEEE 802.15.4e TSCH and DSME

International audienceThe recent IEEE 802.15.4e standard has introduced two interesting modes of operation: Time Slotted Channel Hopping (TSCH) and Deterministic and Synchronous Multi-channel Extension (DSME). Both provide a mix of time and frequency division to improve the performance of the previously available synchronized MAC mode (beacon-enabled 802.15.4). In this paper, we compare the performance of DSME and TSCH with respect to the energy consumption, throughput, and delay through an analysis of their respective ways of operation. We use an energy consumption model coming from our previous experience on the design of recent energy harvesting motes for the GreenNet platform. Our results show that DSME performs slightly better in terms of the energy consumption spent in data transfers. Both protocols exhibit similar delays for a given duty cycle, nevertheless, TSCH obtains shorter delay and higher throughput for low duty cycles. For higher duty cycles, TSCH results in lower throughput—for applications that send little data, the fixed slot configuration of TSCH results in wasted bandwidth. DSME can allocate shorter slots, which is beneficial for applications that transmit short packets

Innovate contactor for CO2 recovery

Innovate contactor for CO2 recover