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The understanding of gas–metal reactions and related surface wettability at high temperatures is often limited due to the lack of in situ surface characterization. Ex situ transfers at low temperature between annealing furnace, wettability device, and analytical tools induce noticeable changes of surface composition distinct from the reality of the phenomena.Therefore, a high temperature wettability device was designed in order to allow in situ sample surface characterization by x-rays photoelectron spectroscopy after gas/metal and liquid metal/solid metal surface reactions. Such airless characterization rules out any contamination and oxidation of surfaces and reveals their real composition after heat treatment and chemical reaction. The device consists of two connected reactors, respectively, dedicated to annealing treatments and wettability measurements. Heat treatments are performed in an infrared lamp furnace in a well-controlled atmosphere conditions designed to reproduce gas–metal reactions occurring during the industrial recrystallization annealing of steels. Wetting experiments are carried out in dispensed drop configuration with the precise control of the deposited droplets kinetic energies. The spreading of drops is followed by a high-speed CCD video camera at 500-2000 frames/s in order to reach information at very low contact time. First trials have started to simulate phenomena occurring during recrystallization annealing and hot-dip galvanizing on polished pure Fe and FeAl8 wt.% samples. The results demonstrate real surface chemistry of steel samples after annealing when they are put in contact with liquid zinc alloy bath during hot-dip galvanizing. The wetting results are compared to literature data and coupled with the characterization of interfacial layers by FEG-Auger. It is fair to conclude that the results show the real interest of such in situ experimental setup for interfacial chemistry studies.

BACKGROUND: In Belgium, the law of "social defense" stipulates that an accused "which is either in a state of dementia or in a serious state of mental disturbance or mental deficiency, incapable of controlling his actions" can be interned. The establishment of social defense (ESD) in Tournai (Belgium) hosts 350 inmates. OBJECTIVES: In collaboration with the Centre for research in social defense, we organized a systematic assessment of patients interned in ESD. This is the first study evaluating prospectively this population. METHODS: Of the total, 229 patients signed informed consent. Different scales of assessment (MINI, WAIS-III, SCID II) were used. Descriptive analyzes were applied (SPSS version 12). RESULTS: We show that 48.8 % of our participants had committed a sexual offense (rape or attempted rape, indecent assault, public outrage or mixed). The average intelligence quotient is 71.4. According to the MINI, 33.2 % of participants showed no psychiatric disorder. Among psychiatric disorders, psychotic disorders are the most represented (37.4 %). According to the SCID, personality disorders were absent in 26.8 % of our participants. Most of the axis II disorders are represented personality disorders related to cluster B (57.3 %) mainly with antisocial personality disorder (37.9 %). CONCLUSION: These data demonstrate the significant heterogeneity of our sample and the need for the establishment of specific care routes to each subpopulation.

Introduction et but de l’etude L’impedancemetrie bioelectrique mesure la resistance au passage d’un courant electrique alternatif indolore a travers le corps. C’est une methode d’application aisee pour la mesure de la composition corporelle des patients, notamment denutris. L’examen permet d’obtenir l’angle de phase (AP ; normale > 5,6°), critere biophysique refletant le fonctionnement cellulaire, ainsi que la masse maigre (MM) et la masse grasse (MG) de l’organisme. L’etude cherchait a determiner quels criteres de composition corporelle et d’etat clinique et metabolique pouvaient influencer l’AP de patients venant en consultation externe de nutrition. Materiel et methodes L’etude etait prospective sur deux mois, aupres de patients ayant de maniere usuelle le releve des criteres suivants : âge, sexe, tour de taille, poids, indice de masse corporelle (IMC), depense energetique de repos calculee (DER ; formules de Harris Benedict), etat nutritionnel, tension arterielle, AP, MM et MG par impedancemetrie multifrequence (QuadScan4000 Bodystat®), pathologie principale, presence ou non d’une nutrition artificielle. L’analyse statistique utilisait le test de Student, l’ANOVA, et l’analyse multivariee par regression logistique pas a pas descendante pour expliquer le critere AP (variables incluses si p Resultats et analyse statistique Cent-soixante-trois patients consecutifs (hommes : 27,6 % ; femmes : 72,4 %) etaient inclus, d’âge 53 ± 17 ans, d’IMC = 27,4 ± 9,4, DER = 1430 ± 331 kcal/j. Parmi, 26,4 % des patients etaient denutris (AP denutris = 4,32 ± 0,86° versus 5,26 ± 1,00° non denutris p Conclusion Cette etude est la seule realisee sur une population de personnes atteintes de pathologies nutritionnelles et vues en consultation externe de nutrition. Elle n’a cependant pas pu prendre en compte la gravite des pathologies des patients suivis. L’AP baisse avec l’âge, et augmente avec la MM des patients. Les resultats vont dans le meme sens que des etudes chez des personnes en bonne sante 1 , 2 , 3 . Ce travail suggere que les patients âges et/ou sarcopeniques pourraient beneficier de mesures de l’AP.

BACKGROUND: In Belgium, the law of "social defense" stipulates that an accused "which is either in a state of dementia or in a serious state of mental disturbance or mental deficiency, incapable of controlling his actions" can be interned. The establishment of social defense (ESD) in Tournai (Belgium) hosts 350 inmates. OBJECTIVES: In collaboration with the Centre for research in social defense, we organized a systematic assessment of patients interned in ESD. This is the first study evaluating prospectively this population. METHODS: Of the total, 229 patients signed informed consent. Different scales of assessment (MINI, WAIS-III, SCID II) were used. Descriptive analyzes were applied (SPSS version 12). RESULTS: We show that 48.8 % of our participants had committed a sexual offense (rape or attempted rape, indecent assault, public outrage or mixed). The average intelligence quotient is 71.4. According to the MINI, 33.2 % of participants showed no psychiatric disorder. Among psychiatric disorders, psychotic disorders are the most represented (37.4 %). According to the SCID, personality disorders were absent in 26.8 % of our participants. Most of the axis II disorders are represented personality disorders related to cluster B (57.3 %) mainly with antisocial personality disorder (37.9 %). CONCLUSION: These data demonstrate the significant heterogeneity of our sample and the need for the establishment of specific care routes to each subpopulation.

XPS and Auger spectroscopies are oflen used in several fields of activity of the steel industry that may be sorted into three items : defectology and expertise, research and development on products and process, study of metallurgical mechanisms. In these fields of activity the results, that we provide our customers with, are obtained within the frame of a "Quality insurance - Certification" approach. This approach is based on the appropriate measures taken by Arcelor Research to give customers every confidence that any error of measurement will be prevented. The few examples in this paper demonstrate how XPS and Auger analysis, performed on samples of small size to study phenomena at a nanometer scale, can be a great help to the industrial line management.

Die heutige Situation der Telekommunikationsindustrie ist gekennzeichnet durch eine ganze Reihe von Widerspruchen und eine Anzahl schizophrener Situationen.

Objectifs pedagogiques Connaitre les principales pathologies cerebrales liees a l’ethylisme. Apprendre les signes IRM de ces pathologies. Connaitre les diagnostics differentiels de ces lesions en imagerie. Messages a retenir L’alcoolisme chronique est un facteur de risque pour les hemorragies cerebrales et l’atrophie cerebelleuse. Certaines pathologies cerebrales sont plus specifiques a l’ethylisme : l’encephalopathie de Gayet et Wernicke, la maladie de Marchiafava-Bignami, la myelinolyse osmotique et l’encephalopathie hepatique. Ces pathologies peuvent engager le pronostic vital. L’IRM joue un role fondamental dans le diagnostic de ces pathologies.

Objectifs pedagogiques Connaitre l’anatomie des nerfs oculomoteurs et les signes cliniques des paralysies oculomotrices. Connaitre les principales etiologies des diplopies binoculaires, notamment les urgences a eliminer. Savoir adapter la technique d’examen a la pathologie recherchee. Messages a retenir La connaissance des signes cliniques permet d’orienter le protocole d’exploration et le moment de sa realisation. L’IRM est l’examen de choix pour l’exploration des diplopies. Cependant, le scanner a une place importante dans le diagnostic de certaines urgences : anevrisme, incarceration musculaire.

Objectifs pedagogiques Connaitre les complications neurologiques. Proposer un protocole d’imagerie diagnostique. Connaitre les modalites de prise en charge. Messages a retenir Les complications neurologiques sont les plus frequentes des complications extra-cardiaques. La realisation d’une IRM chez un patient asymptomatique, porteur d’une endocardite infectieuse, permet de depister certains sujets porteurs d’anevrysme mycotique, et de les orienter vers un traitement adapte, avant complication. L’anevrysme mycotique, de par son caractere evolutif aleatoire, est de prise en charge controversee. Une exclusion par voie endovasculaire doit etre discutee des le diagnostic pose.

Failure of the reverse characteristic of power devices may be caused by an increase of field strength due to doping inhomogeneities. A numerical program has been developed to calculate the effect of various types of perturbations on the maximum occurring field strength and on the shape of the space charge region. Three-dimensional calculations show that the influence of inhomogeneities can partly be compensated by the surrounding material. On the other hand, spikes of the diffusion front or p-islands with a high doping concentration inside the lowly doped n-region may cause an increase of field strength, which is not expected from the one-dimensional model.

A theoretical analysis is made of the field distribution near the surface of p-n-p structures with double positive edge geometry. This geometry offers in principle the possibility of avoiding the limitations and disadvantages inherent in the use of negative bevel angles. The results show that the reduction of the maximum field at the surface is not as easy as for the case of a simple positive bevel angle and that consequently the passivation of the surface may present more problems. Nevertheless, it is demonstrated that this geometry offers a number of great advantages and presents a real alternative for use in future high-voltage devices. A number of devices, dimensioned for a breakdown voltage of 6 kV, were made with this edge geometry. The measurements show that the reverse current corresponds to the thermally generated current in the space-charge layer and that no significant current flows at the surface. The breakdown voltage corresponds to the theoretical breakdown voltage in the bulk, unlike in the case of double negative beveling. The advantages of this geometry with respect to the conventional negative bevel angle are no significant reduction of active area, no dependence on the doping profile, and no limitation in voltage. A disadvantage, however, is the presence of higher fields at the surface.

Under electrical load the crystal temperature inside a semiconductor power device changes substantially both in space and in time. Its measurement with good resolution in temperature, in time as well as in space, was attempted by detecting the thermal radiation emitted from an operational semiconductor device that was thick enough to be opaque to thermal infrared. A cooled InSb detector is followed by an amplifier allowing for a tradeoff between time resolution (the overall time constant varied from 0.5 to 86 µs) and temperature resolution, such that their product remained constant. For temperature fields periodic in time, sampling methods and signal averaging are applied which further improve temperature resolution with time and space resolution remaining unchanged. A large improvement in speed of response with respect to conventional methods results. For a fixed surface point the time dependence of temperature is obtained. Fixing the observation window in time leads to profiles of instantaneous temperature across a selected line of the exposed semiconductor which are in good agreement with those predicted by a recent theoretical model. In Part I the case of thick slices is treated. The extension to thin slices which are transparent to thermal infrared are treated in Part II.

A model is developed for the dynamic operation of magnetic reed relays. From experimental data, it is found that the processes of dynamic magnetization and mechanical motion can be treated as separate and consecutive in time. Remarkable agreement was found between the experimentally determined static magnetic force and a force calculation based on an assumed domain structure inside the reed tips. The model basically assumes that the flux passes through the air gap in two areas near the tips of the reeds, each area equals half the cross-sectional area of the reed. The dynamic magnetization process is modeled with an improved version of Agarwal's [7] model for eddy-current losses in laminations, and a differential equation for dynamic reed motion is derived. The very good agreement between theoretical and experimental results shows that this model gives a good representation of the dynamics of the system. Furthermore, the findings of the static force model based on domain concepts have basic application to the knowledge of magnetics in addition to the application here to reed relays.

A new method for investigating the field distribution near the surface of p-n junctions is presented. The results show that for negatively beveled junctions, an absolute field maximum exists underneath the surface. This field maximum rather than the field on the surface determines the breakdown voltage of the device. The dependency of the maximum field on various device parameters as base resistivity, bevel angle, and steepness of the doping profile is analyzed. In addition, the influence of surface charges and dielectrics is investigated. Finally, the advantages of positive bevel angles with respect to negative ones are demonstrated. The theoretical results were verified by potential probing measurements on the surface of high-voltage devices.

Colimycin is sulfomethylated in order to inactivate it temporarily in vivo. In vitro, this process may have unexpected results because the experiment is carried out within a closed system. The time required to activate the antibiotic varies according to incubation conditions. The freed sulfomethyl groups are probably eliminated in vivo. In vitro, these residues may interact with the outer membrane of Escherichia coli B which is charged with badly positioned molecules of colimycin, thus creating a barrier for the active molecules. As the expected mechanism of polymyxin B or E action include first electrostatic interactions, it is not surprising that a modification of the ionic balance of the medium should be of such importance.

Particle counting immunoassay is based on latex agglutination, the reaction being measured by instrument counting of the particles remaining unagglutinated. Most interference which generally affects latex agglutination can be avoided by pepsin digestion of the sample, provided the antigen (Ag) of interest resists pepsin, which is the case of the hepatitis B surface antigen (HBsAg). Pepsin treatment has the additional advantage of inactivating antibodies and so releasing the Ag from immune complexes. We have set up an assay of HBsAg, proceeding in a prototype of Impact Instrument (Acade Diagnostic Systems, Belgium) at a rate of 60 samples.h-1 and a total running time of 2 or 4 h. This assay was compared with Abbott radioimmunoassay (RIA) in 706 consecutive patients (A) and 31 selected sera for which values close to the cut-off had been obtained by RIA (B). In A, 38 sera were found positive and 668 negative by both methods. In B, RIA after neutralization classified the samples as positive (n = 14), negative (n = 14), or dubious (n = 3). Complete agreement between latex and RIA was achieved for nine positive, 12 negative, and two dubious samples. Of five RIA-positive samples, two were classified as latex-negative and three as dubious in the latex assay. One sample dubious in RIA was found latex-positive and two RIA-negative samples were found, respectively, latex-positive and dubious; when retested after pepsin digestion, the first of them became RIA-positive.(ABSTRACT TRUNCATED AT 250 WORDS)

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Analytical solutions for the forward characteristic of thyristors have been limited to abrupt and constant doping profiles. Average values for the mobilities and the carrier lifetime had to be assumed for each region of the device. Results will be presented here which are based on an exact numerical solution of the transport, continuity, and Poisson equations for the one-dimensional thyristor. Doping, mobility, and lifetime can be varied from point to point. Thyristor structures are much wider and higher doped than the devices treated numerically in the literature. The dependency of the forward characteristic on various device parameters was examined, and the important results were verified experimentally. For high current and a base width that is large compared to the diffusion length, the dependency of mobility on the carrier concentration leads to a base voltage drop significantly lower than that expected from analytical theory. Furthermore, it is shown that for this case the parameters of the highly doped side regions (doping, width, and lifetime) have much less influence than predicted from Herlet's [3] theory.

Experience with beveled p-n junctions does not fully agree with the predictions of Davies and Gentry. Specifically no optimum negative angle as claimed by Huth and Davies was found. A new method for determining the form of the space charge region near the surface shall be presented which avoids the insufficiencies of the model cited. Apart from more accurate results, this paper gives insight into an entirely new phenomenon. In contrast to conventional theory p-n junctions with small negative bevel angles exhibit an absolute electric field maximum underneath the surface. This effect causes a reduction of the breakdown voltage even when the electric field on the surface is sufficiently small. Results will be presented which show the dependency of the absolute field maximum on bevel angle, doping profile and material resistivity. It will be shown that a limit for the use of negative bevel angles exists at about 4 kV breakdown voltage. These theoretical predictions are in excellent agreement with potential probing experiments. Results will also be presented on the influence of dielectrics or charges on the surface.

Infrared microscopy as a means for observing dynamic thermal processes inside a slice out from a silicon power device has been reported by Burtsev et. al. and refined by Jaecklin and Marek. Since the local emissivity depends on doping, instantaneous free carrier concentration and the optics used, interpretation of these radiation measurements is extremely difficult. In the existing literature it has been based on homogeneous emissivity throughout the sample.