Photodétecteurs en intégration monolithique sur guides optiques : modélisation et vérifications expérimentales

The authors developed a model on optical guided structures with complex refractive indices, on 9 desktop-computer. This model allows to predict the coupling efficiency of photodetectors monolithically integrated with optical waveguides. An oscillatory behaviour of the absorption coefficient versus the absorbing layer thinkness has been pointed out. Comparisons with experimental resuylts obtained with device made in different laboratories show a good agrement     

Modeling and analysis of an unreliable flow line composed of parallel-machine stages

This paper focuses on flow lines composed of multiple parallel-machine stages. The system is similar to a classical flow line, the only difference being that a given stage may consist of parallel machines. A method for modeling and analyzing this type of flow lines is presented. The technique used amounts to replacing each parallel-machine stage by a single equivalent machine in order to obtain a classically-structured flow line with machines in series. Equations for computing the parameters of equivalent machines are submitted. These parameters can then be used to carry out performance diagnosis of the corresponding stage, or as input data for existing analysis methods to evaluate the production performance of flow lines. The method presented in this paper has been successfully implemented and tested in the industry over the past few years.     

Transfer, Perception, and Activity of Male Pheromone of Acrolepiopsis assectella with Special Reference to Conspecific Male Sexual Inhibition

In the leek moth, Acrolepiopsis assectella, the male, stimulated by a calling female, produces a sexual pheromone that is active on the female. The male-produced pheromone blend contains eight alkanes previously isolated from the male hair-pencils. We used EAG techniques to study the effect of the pheromone on females reared on leek or on artificial diet and on males reared on leek. The optimal stimulation duration appeared to be 1.6 sec exposure to the pheromone or components. The concentrations tested on the antenna were of the order of 10¹² molecules/cm³. The hair-pencil extract tested was of an estimated concentration of around 10⁹ molecules/cm³. The antennal responses are expressed relative to responses to a standard, amyl acetate, but also as an absolute value. Generally, females reared on artificial diet and males reared on leek responded better than females reared on leek. Of the alkanes tested, those present in hair-pencils gave higher responses, with hexadecane always giving the strongest response. A possible inhibiting activity of male leek moth pheromone on the sexual behavior of conspecific males was investigated. The behavior of sexually stimulated males was observed in the presence of other males, hair-pencil extracts, and different compounds either pure or in a mixture. The experiments established that in this species, male pheromone inhibits wing fluttering duration of conspecific males. This inhibition was obtained not only with fluttering males as a source of pheromone but also with all the alkanes tested. The inhibition was due to hair-pencil chemicals, particularly if these were perceived by olfaction plus contact. Wing fluttering increased the inhibitory activity of male-derived alkanes.     

Détection d’obstacles routiers par stéréovision : l’approche « v-disparité »

This paper presents an innovating real time method for detecting road obstacles by on board stereovision. After having exposed the stakes of the obstacles detection, having presented the state of the art and having identified the problems to be solved, the developed approach is described. It is based on the analysis of the “v-disparity” image, which provides a suitable representation of the geometric content of the road scene. The method is then evaluated with respect to the problems generally affecting stereovision approaches. The theoretical good properties of the “v-disparity” algorithm — genericity, effectiveness, robustness, and computational efficiency — are thus experimentally confirmed. Thanks to the performances obtained, the described algorithm is used for on board driving assistance applications.     

Oxidative Metabolism of Ferrocene Analogues of Tamoxifen: Characterization and Antiproliferative Activities of the Metabolites

Ferrociphenols have been found to have high antiproliferative activity against estrogen‐independent breast cancer cells. The rat and human liver microsome‐mediated metabolism of three compounds of the ferrocifen ( FC ) family, 1,1‐bis(4‐hydroxyphenyl)‐2‐ferrocenyl‐but‐1‐ene ( FC1 ), 1‐(4‐hydroxyphenyl)‐1‐(phenyl)‐2‐ferrocenyl‐but‐1‐ene ( FC2 ), and 1‐[4‐(3‐dimethylaminopropoxy)phenyl]‐1‐(4‐hydroxyphenyl)‐2‐ferrocenyl‐but‐1‐ene ( FC3 ), was studied. Three main metabolite classes were identified: quinone methides ( QM s) deriving from two‐electron oxidation of FC s, cyclic indene products ( CP s) deriving from acid‐catalyzed cyclization of QM s, and allylic alcohols ( AA s) deriving from hydroxylation of FC s. These metabolites are generated by cytochromes P450 (P450s), as shown by experiments with either N‐benzylimidazole as a P450 inhibitor or recombinant human P450s. Such P450‐dependent oxidation of the phenol function and hydroxylation of the allylic CH₂ group of FC s leads to the formation of QM and AA metabolites, respectively. Some of the new ferrociphenols obtained in this study were found to exhibit remarkable antiproliferative effects toward MDA‐MB‐231 hormone‐independent breast cancer cells.