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We are building the Schenberg gravitational wave detector at the Physics Institute of the University of Sao Paulo as programmed by the Brazilian Graviton Project. The antenna and its vibration isolation system are already built, and we have made a first cryogenic run for an overall test, in which we measured the antenna mechanical Q (figure of merit). We also have built a 10.21 GHz oscillator with phase noise performance better than -120 dBc at 3.2 kHz to pump an initial CuA16% two-mode transducer. We plan to prepare this spherical antenna for a first operational run at 4.2 K with a single transducer and an initial target sensitivity of h ∼ 2 x 10 -21 Hz -1/2 in a 50 Hz bandwidth around 3.2 kHz soon. Here we present details of this plan and some recent results of the development of this project.

Based on a reduced-order model of a cement grinding circuit, a non linear model predictive control strategy is developed. The first step of this NMPC study is the definition of control objectives which consider product fineness, product flow rate and/or grinding efficiency. At this stage, one of the main concerns is to relate these objectives to easily measurahle particle weight fractions. Second, NMPC is implemented so as to take the various constraints on the manipulated variables and operating conditions of the mill into account. Third, robustness with respect to model uncertainties is analyzed, and the most critical parameters are highlighted. Finally, an NMPC scheme, combining a stable inner loop for controlling the mill flow rate and a DMC-like compensation of the model mismatch, is proposed.

Introduction La lymphangite carcinomateuse pulmonaire (LK) est une entite mal connue qui semble neanmoins affecter defavorablement le pronostic du carcinome bronchique non a petites cellules (CBNPC) de stade IV ( Fig. 1 ). Methodes Nous avons retrospectivement etudie des patients avec une LK scanographique formelle (LKF) compare a des groupes LK possible (LKP) et temoins (sans LK) atteints d’un CBNPC de stade IV avec ajustement sur des facteurs pronostiques (âge, sexe, histologie, profil moleculaire, performans statut, acces a la chimiotherapie). Resultats Sur 533 patients suivis pour un CBNPC stade IV, 41 (7,7 %) etaient classes comme LKF, 61 (11,4 %) comme LKP et les groupes temoins comprenaient 66 patients (12,4 %) avec une atteinte M1a et 365 patients (68,5 %) avec une atteinte M1b, sans LK associee. Le groupe LKF comprenait plus d’adenocarcinomes que les temoins (p = 0,0053) et plus d’alteration moleculaire EGFR ou ALK (p = 0,043). La cause premiere de deces des LKF etait la detresse respiratoire aigue (68,4 %). La mediane de survie du groupe LKF apres diagnostic de LK etait de 118 jours. La mediane de survie etait inferieure dans le groupe LKF par rapport au groupe M1b en analyse univariee (238,3 jours [61–280] contre 365,6 jours [99–504], p = 0,0016) et apres ajustement (p = 0,0024). Parmi les patients du groupe LKF, ceux controles sous chimiotherapie (repondeurs ou stables apres la reevaluation suivant le diagnostic de lymphangite) avaient une meilleure mediane de survie : 303 contre 103 jours (p = 0,000014). Les patients du groupe LKF presentant une alteration moleculaire EGFR ou ALK avaient egalement un pronostic plus favorable avec une mediane de survie a 311 contre 126,5 jours (p = 0,00031). Conclusion La LK a donc un impact pronostique majeur dans le cancer bronchique. Sa genese et son pronostic semblent neanmoins dependants du profil moleculaire tumoral. Le pronostic semble etre du a la chimiosensibilite tumorale, l’acces a la chimiotherapie et l’impact sur la fonction pulmonaire.

Learning, i.e. estimation of weights and biases in neural networks, involves the minimization of an output error criterion, a problem which is usually solved using back-propagation algorithms. This paper aims to assess the potential of simultaneous perturbation stochastic approximation (SPSA) algorithms to handle this minimization problem. In particular, a variation of the first-order SPSA algorithm that makes use of several numerical artifices including adaptive gain sequences, gradient smoothing and a step rejection procedure is developed. For illustration purposes, several application examples in the identification and control of nonlinear dynamic systems are presented. This numerical evaluation includes the development of neural network models as well as the design of a model-based predictive neural PID controller.

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la mise au point d'un modele de simulation de la derniere passe du laminage a chaud du cuivre ne presente a priori pas de probleme du point de vue numerique pour un code d'elements finis non lineaire. La collecte d'informations precises tant sur le procede industriel que sur le comportement du materiau est par contre une operation non triviale. Cet article presente les diverses methodes experimentales mises en oeuvre pour caracteriser le materiau: essais de compression a chaud, mesures d'analyse thermique differentielle, essais de dilatometrie et de diffusivite. Les methodes permettant d'identifier les parametres de la loi elasto-visco-plastique de type Norton-Hoff a partir des essais sont presentees et une analyse bibliographique investigue le probleme de la determination du module de Young a haute temperature. Tant les hypotheses supplementaires relatives au procede et necessaires au modele que les resultats finaux sont resumes.

In this study a class of dynamic models based on metabolic reaction pathways is analysed, showing that systems with complex intracellular reaction networks can be represented by macroscopic reactions relating extracellular components only. Based on rigorous assumptions, the model reduction procedure is systematic and allows an equivalent 'input-output' representation of the system to be derived. The procedure is illustrated with a few examples.

The purpose of this paper is to show that a distributed-parameter model of a continuous ball mill can be developed by discretizing the particle size continuum into a few size intervals only. Despite this coarse discretization of the particle size distribution, the ball mill model provides a good representation of the real process, which can be combined with a classifier model to build a complete simulator of a closed-loop grinding circuit. This simplified process representation is compared with a detailed first-principle model previously developed and validated by the authors. The main advantage of the simplified model is that it can be easily incorporated in an on-line control scheme. For illustrative purposes, a NMPC scheme is implemented to regulate the product fineness when variations in the grindability of the raw material occur as a measurable disturbance. The control objective, based on a size interval content, is compatible with traditional fineness measurements.

Cardiovascular prosthetic bypass grafts do not endothelialize spontaneously in humans, and so they pose a thrombotic risk. Seeding with cells improves their performance, particularly in small-caliber applications. Knitted tubular polyethylene-terephthalate (PET) vascular prostheses (6 mm) with commercial type I collagen (PET/Co) were modified in the lumen by the adsorption of laminin (LM), by coating with a fibrin network (Fb) or a combination of Fb and fibronectin (Fb/FN). Primary human saphenous vein endothelial cells were seeded (1.50 × 105/cm2), cultured for 72 h and exposed to laminar shear stress 15 dyn/cm2 for 40 and 120 min. The control static grafts were excluded from shearing. The cell adherence after 4 h on PET/Co, PET/Co +LM, PET/Co +Fb and PET/Co +Fb/FN was 22 %, 30 %, 19 % and 27 % of seeding, respectively. Compared to the static grafts, the cell density on PET/Co and PET/Co +LM dropped to 61 % and 50 %, respectively, after 120 min of flow. The cells on PET/Co +Fb and PET/Co +Fb/FN did not show any detachment during 2 h of shear stress. Pre-coating the clinically-used PET/Co vascular prosthesis with LM or Fb/FN adhesive protein assemblies promotes the adherence of endothelium. Cell retention under flow is improved particularly on fibrin-containing (Fb and Fb/FN) surfaces.

The sparsity and low quality of measurement data in biochemical applications often make the development of black-box neural network models particularly delicate. Hence, it is appealing to resort to a hybrid physical-neural network approach, which combines a first-principles model and a partial neural network model. In this study, the hybrid approach is applied to a real case study, e.g. batch CHO animal cell cultures. Two alternative model structures are developed, in which NNs are used to describe either the reaction kinetics or the complete reaction rates (including the reaction pseudostoichiometry). Parameters and initial conditions are estimated from experimental data using a maximum likelihood approach, which takes all the measurement errors into account. A special procedure for initializing the minimization of the objective function is devised. The good model agreement is demonstrated with cross-validation tests.

Diamond films were elaborated in CH 4 –H 2 –N 2 and CH 4 –CO 2 –N 2 gas mixtures in a pulsed microwave plasma under the same working conditions, varying the percentage of nitrogen from 0.1 to 5.2%. Raman spectroscopy was used to probe the quality of the film and the incorporation of nitrogen within diamond films was appreciated using cathodoluminescence (CL) spectroscopy. The intensities of peaks due to nitrogen-vacancy pairs showed that the quantity of incorporated nitrogen increased with that of the nitrogen introduced in the gas mixture. Arrhenius plots of the electrical conductivity showed that the incorporation of low quantities of nitrogen in the diamond film led to an increase in its resistivity. It can be speculated that small quantities of incorporated nitrogen balance the natural p -doping of microwave plasma chemical vapor deposition (MPCVD) diamond and, thus, enhance its insulating properties. Nevertheless, as higher quantities of nitrogen were incorporated, the resistivity of the diamond film decreased due to a possible n -doping. The doping hypothesis was confirmed by I–V measurements which exhibited a rectifier behavior of the n -diamond/ p -Si heterojunction structure. This behavior was observed only in the case of a CO 2 –CH 4 gas mixture, where a high concentration of nitrogen could be incorporated without affecting the continuity of the film.

Resume Le travail presente rapporte une demarche, a savoir les differentes etapes d'une evaluation dans la perspective de l'elaboration d'un substitut vasculaire artificiel hybride, concept qui prevoit d'associer dans une meme unite fonctionnelle une composante artificielle d'origine synthetique ou naturelle et une composante cellulaire: l'endothelium vasculaire. Les resultats des essais cliniques les plus recents rapportes dans la litterature, a condition que le revetement endothelial du substitut soit complet au moment de l'implantation, permettent d'envisager l'utilisation de telles structures cellularisees. Les differentes etapes de cette etude comportent: (1) la selection d'un materiau propice a l'endothelialisation in vitro par des etudes de cytocompatibilite, a l'aide de cellules endotheliales en culture; (2) l'etude du phenotype de la composante biologique endotheliale au contact des materiaux selectionnes (mesures de la production et de la fonctionnalite de deux proteines-cle de la regulation de la balance hemostatique, quantification d'une molecule d'adhesion exprimee a la membrane de la cellule endotheliale, intervenant dans le recrutement des leucocytes en cas de processus inflammatoire; (3) l'etude du devenir du neo-endothelium obtenu, sous contraintes de cisaillement, par quantification de la radioactivite apres radiomarquage in situ de la monocouche cellulaire.

Dans le cadre d’une convention de recherche entre la Faculte Polytechnique de Mons et Cockerill Sambre, un simulateur des structures de controle de l’epaisseur en laminage a froid a ete developpe. La modelisation realisee a concerne plus specifiquement le laminoir tandem 4 cages continu de Tilleur.Le simulateur, developpe a l’aide du logiciel MATLAB® sous SIMULINK® , est base sur un modele lineaire de la force, du couple et du glissement necessitant la connaissance de coefficients de sensibilite. Les capteurs et les actionneurs sont, quant a eux, modelises via l’identification de leur fonction de transfert.Ce simulateur a notamment ete utilise dans le cadre des investissements realises sur le laminoir tandem 4 cages continu de Tilleur au debut de l’annee 1999.

A microwave plasma of H2–CH4–N2 gas mixture used for diamond film deposition has been characterized by optical emission spectroscopy in the continuous and in the pulsed modes. In the continuous mode, a dynamic form of actinometric optical emission spectroscopy was used to determine temporal trends in the concentrations of H, CH and CN species following the cut-off of either the CH4 or N2 flows. These data show that the gas-phase reactions play a major role in the production of the above-mentioned species, but also the plasma–diamond surface reactions contribute significantly to the production of the CN radical. In the pulsed-discharge mode, time-resolved optical emission spectroscopy was used to determine the evolution of the relative concentrations of reactive species H, CH, CN and Ar with time. This evolution during the discharge, post-discharge and transient stages gives information on the processes leading to the population of excited states.

This paper considers the problem of sensor configuration for parameter and/or state estimation in distributed parameter systems. A practical criterion for assessing the influence of the sensor configuration is presented, which is based on a measure of independence of the sensor responses in the case of state estimation, and on a measure of independence of the sensitivity functions in the case of parameter estimation, respectively. The procedure is illustrated with the optimal placement of temperature sensors in a catalytic fixed-bed reactor.

This paper focuses on modelling of an industrial cement grinding circuit using physical arguments and experimental data. The resulting ‘grey-box’ model, which consists of a mixed set of algebraic and partial differential equations, can be used to gain some insight into the process dynamics and design control loops to achieve product specifications. Several multivariable control schemes using feed rate and classifier speed as manipulated variables, and the circulating material flow rates and/or the fineness of the product as controlled variables, respectively, are compared and the influence of disturbances, i.e., variations in the material grindability, is investigated.

High angular resolution ground-based direct imaging (V, R, Ic) of the double QSO HE 1104–1805 has been obtained with the NOT and NTT telescopes. Analysis of these data led to the first detection of the lensing galaxy. Direct imaging of HE 1104–1805 has subsequently been carried out with the Planetary Camera (WFPC2) through the F555W (nearly Johnson V) and F814W (nearly Kron-Cousins Ic) filters onboard HST. These images confirm the presence of the deflector between the two lensed quasar components (A & B). Direct imaging of this system in the near infrared (IR) at 2.2 μm (K′), with IRAC-2b at the Cassegrain focus of the ESO/MPI 2.2 m telescope, indicates that the additional component is indeed a very red extended object with magnitude K ≈ 16.5. We present deconvolutions of the HST and IR images using the 2-channel PLUCY method. From the HST observations, we also report very accurate relative positions and brightnesses of the QSO components. By comparison between the ground-based and the HST observations, from February–March 1994 to November 1995, we possibly detect the fading of component A by ∼0.3 magnitudes in the optical and a corresponding fading of B by about half this value. The observed monotonic decrease of the magnitude difference between B and A as a function of wavelength is consistent with a partial amplification of the A component by microlensing. Evolutionary models for galaxies show that, in order to produce the observed colour indices V − Ic > 2 and 4 11 h 50 M ⊙ L ⊙ ) for the galaxy is large but does not imply an excess of dark matter with respect to other well known lensing galaxies.

Deposition of diamond layers in a CH4–CO2 microwave discharge operating in pulsed mode was achieved. The effects of nitrogen addition and microwave power modulation on the plasma reactivity were studied by time resolved optical emission spectroscopy. An enhancement of the molecular dissociation during the early stage of the pulse has been observed. The resulting diamond layers showed less graphite contamination as compared with that obtained in continuous discharge. Furthermore, the addition of nitrogen to the discharge operating in this pulsed mode further decreases the graphite contamination and improves crystallization due to reduction of secondary germination.

The diamond nucleation on silicon has been a subject of different interests in previous years in order to understand and improve diamond growth. In this work, we develop a new silicon surface chemical preparation based on silicon surface passivation before plasma treatment, which stabilises the surface and so favours diamond epitaxy on silicon. This treatment allows us to remove native oxide layer and to saturate dangling bonds with H atoms. This would limit the surface reconstruction. We notice that seeding the silicon surface with diamond powder grain size of 40 μm, following surface passivation, increases the nucleation density and so limits the graphite contribution on diamond films obtained.

A multipath model of the mechanical behaviour of healthy lungs subject to a plethysmographic test (close to quiet breathing conditions) has been developed, which includes the main physiological nonlinearities. This model is built on a symmetric branching scheme based on Weibel's data, and uses non-linear fluid equations for the upper and lower airways. The alveolar gas compression, the changes in airway dimensions related to lung volume and/or transmural pressure, and the respiratory swings in glottic aperture have been taken into account. As clinically observed, the behaviour of the lungs, taken as a whole, seems linear, but it is confirmed by simulation that this linearity is only apparent. Simplifications and linearisations therefore need to be made carefully, only after their impact on the global behaviour of the lung is evaluated.

The addition of nitrogen to the CH 4 -H 2 gas mixture used for diamond growth by microwave plasma assisted chemical vapour deposition (MPACVD) strongly modifies the plasma reactivity and thus the deposition rate, the structure, and the physical properties of the films. It has been pointed out that nitrogen reduces the relative concentration of carbon deposition precursors such as CH and strongly enhances the etching process. When a diamond film is present in the centre of the plasma, a relatively high CN concentration could be detected in the discharge even after closing the gas line introducing methane in the gas flow. This can be considered as evidence of the etching of the diamond film by the plasma, resulting in the formation of CN radicals. The effect of nitrogen on the structure and quality of diamond films is discussed from the results of scanning electron microscopy and Raman spectroscopy.

The Cloverleaf quasar, H1413+117, has been photometrically monitored at ESO (La Silla, Chile) and with the NOT (La Palma, Spain) during the period 1987-1994. All good quality CCD frames have been successfully analysed using two independent methods (i.e. an automatic image decomposition technique and an interactive CLEAN algorithm). The photometric results from the two methods are found to be very similar, and they show that the four lensed QSO images vary significantly in brightness (by up to 0.45 mag), nearly in parallel. The lightcurve of the D component presents some slight departures from the general trend which are very likely caused by micro-lensing effects. Upper limits, at the 99% confidence level, of 150 days on the absolute value for the time delays between the photometric lightcurves of this quadruply imaged variable QSO, are derived. This is unfortunately too large to constrain the lens model but there is little doubt that a better sampling of the lightcurves should allow to accurately derive these time delays. Pending a direct detection of the lensing galaxy (position and redshift), this system thus constitutes another good candidate for a direct and independent determination of the Hubble parameter.

Deposition of diamond layers from a CH4-H2 microwave discharge operating in pulse mode was achieved. The resulting diamond layers showed less graphite contamination as compared with that obtained in continuous discharge. Furthermore the addition of nitrogen to the discharge operating in this pulse mode was shown to further decrease the graphite contamination and to improve crystallisation due to reduction of secondary germination. However using nitrogen in the gas mixture resulted also in a decrease in nucleation density and in discontinuous formation of diamond layers.

Gas phase synthesis of MTBE from methanol and isobutene has been investigated over different zeolites. It is shown that bulk Si/Al ratio has a marked influence on the formation of MTBE. H-beta zeolite was found to be as active as acid Amberlyst-15 (reference catalyst), and noticeably superior to non- and dealuminated forms of H-Y, H-ZSM-5, zeolite omega, and H-mordenites. Screening test results obtained over other catalysts (SAPOs and pillared clays) are briefly commented. The contribution of the external surface of the zeolites to the reaction is discussed. In the case of H-Y zeolites, it is shown that extraframework Al species (Al-27 NMR signal at 30 ppm) have a detrimental effect on the reaction. (C) 1997 Academic Press.

The effect of nitrogen on the growth of diamond by microwave plasma-assisted chemical vapour deposition, when added in a H2CH4 gas mixture was investigated by micro-Raman spectroscopy and by scanning electron microscopy. A clear improvement in the surface morphology and quality of the diamond films indicates the beneficial effect of adding nitrogen to the gas mixture. The concomitant study of plasma parameters and diamond films properties leads to a better understanding of the effect of nitrogen in the diamond growth process and to the determination of optimal concentrations of nitrogen and methane in the mixture. We report in this paper the effect of varying the concentration of nitrogen introduced in different H2CH4 mixtures. The plasma reactivity is studied by optical emission spectroscopy during diamond film growth, and we focus our experiments on the variation of the emission line of the CH and CN radicals. These species can be considered as key species to explain reactions of the nitrogen in the gaseous phase and its interaction with the surface of the film in growth.

In the well-known classical determination of the index and thickness of thin transparent films formed on known substrates from the ellipsometric data, the film thickness is computed from its index value which is found first, independently of the former. However, these parameters of very thin films well under 100 A may not be accurately thus determined in the presence of experimental angular errors particularly that in the angle of incidence. In this paper, not only the film parameters but also the angle of incidence are found using a new method from the ellipsometric data measured on two film-absorbing substrate reflecting system formed with the same transparent film but up to different thicknesses. The parameters obtained and their uncertainties estimated from the two methods are compared and consequently the limits of application of the methods are defined. The new method shows resistance to the propagation of angular errors to the parameters sought. Furthermore, a correlation detectedn between the error in the substrate real index and the uncertainty in the angle of incidence computed allows one to correct one of these by making use of the angle of incidence measured. These results are illustrated by applying the method presented to recently published experimental data.

Parameter estimation in distributed parameter systems is usually accomplished by minimizing an output least square criterion, which is defined implicitly through the solution of the model equations. This paper addresses itself to the numerical procedure used to compute the criterion gradient with respect to the unknown parameters. Several methods ranging from the straigthforward finite difference approximations to the more involved adjoint variable method are described and their relative merits are highligthed. An experiment design procedure based on the sensitivity matrix is presented. The methods for gradient computation and experiment design have been succesfuily applied to several test examples and are illustrated in this paper by a convective-diffusion problem.

Long before the neologism “Cogeneration” was coined (around 1978), UEM’s Chambie`re Power Plant—which dates back to the turn of the century—was already supplying the city of Metz, east of France, with combined heat and power. In 1992, Chambie`re experienced a major turning point in its history with the installation of a new unit based on one MS 6001B “Heavy Duty” gas turbine. This model, rated 38 MWe-ISO and burning natural gas or fuel oil, has become the core of a new cogeneration unit exhibiting outstanding performance: • efficiency higher than 80 percent (LHV) providing a 20 percent energy saving in comparison to a conventional plant, • low pollutant emissions (NOx, CO, HC) and low contribution to the greenhouse effect (CO2). The gas turbine has been equipped with two steam injection devices, for DeNOx and power augmentation, respectively, resulting in a very flexible system. After describing the power plant and giving its main achievements in the fields of energy and emissions, the paper briefly presents several improvements intended to protect both the turbine and the environment.

Resume Le syndrome du cimeterre est caracterise par un retour veineux pulmonaire anormal se drainant dans la veine cave inferieure, avec presence radiologique d'un aspect incurve de la veine pulmonaire droite vers le dedans. Le but de cet article est de rapporter quatre observations dans lesquelles le syndrome du cimeterre est associe a une absence anatomique ou fonctionnelle de l'artere pulmonaire droite. Observations. — Un diagnostic de syndrome du cimeterre a ete porte chez quatre patients âges de 3, 10, 23 et 33 ans. La scintigraphie pulmonaire et/ou la tomodensitometrie a permis de reconnaitre le syndrome du cimeterre et de preciser le type de la vascularisation pulmonaire et systemique. Dans les quatre observations, la vascularisation du poumon droit ne prenait pas son origine du tronc de l'artere pulmonaire mais provenait de vaisseaux systemiques dont l'origine etait l'aorte abdominale. L'artere pulmonaire droite etait vascularisee a « contre-courant a par les vaisseaux systemiques (deux observations); dans les deux autres observations, la circulation dans l'artere pulmonaire droite etait assuree directement par les vaisseaux systemiques, l'artere pulmonaire etant anatomiquement absente. Les pressions arterielles pulmonaires etaient normales dans les quatre observations; il en etait de meme de la tolerance fonctionnelle dans trois cas; le dernier cas presentait des hemoptysies repetees et severes qui ont necessite une pneumonectomie droite. Conclusions. — Ces quatre observations sont comparees a six autres recueillies dans la litterature. Des methodes « elegantes a et non invasives d'exploration sont maintenant disponibles pour porter le diagnostic de syndrome du cimeterre et preciser le type de la vascularisation pulmonaire.

The thermal behavior of the constant volume body plethysmograph under the thermal effect of the patient and the thermostatic bag is modeled by two relations: the first is between the temperature in the box and the heat flux generated by the patient and the bag, and the second is between the pressure in the box and the same flux. When the heat flux evolves as a step function, the temperature and the pressure are characterized by four time constants, the theoretical values of which are functions of the heat transfer coefficients by natural convection between the faces of the walls, and the air inside and outside the box. Only two of these four theoretical constants can be experimentally measured with reasonable precision. One of these is responsible for an important delay between the installation of the patient in the box and the disappearance of the disturbance thereby created in the pressure signal. Investigations with patients and with three different plethysmographs each built of a different material (wood, PVC, and Perspex) show the influence of the construction material on the waiting period before the disappearance of the disturbance in the pressure signal. >

Castleman disease is a rare disorder of the lymphoid system which can be classified into two clinical groups, monocentric disease versus multicentric disease, and two histological types, the hyaline vascular form versus the plasma cell form. We report three cases of monocentric Castleman disease. The first one is a classical form of Castleman's disease. The second one is characterized by an uncommon radiological presentation, with a calcification within the tumor. The third one is a plasma cell form with monoclonal proliferation associated with a monoclonal gammapathy. These three cases highlight the polymorphic clinical and radiological features of Castleman disease. They underlie the difficulty of surgical resection due to the tumor vascularization. Other diagnosis hypothesis and associated diseases will also be discussed (HIV, Kaposi's sarcoma, POEMS syndrome).

OBJECTIVES: To determine the potential for delafloxacin to select for resistant mutants in methicillin-resistant Staphylococcus aureus (MRSA), including isolates with existing mutations in the quinolone resistance determining region (QRDR). METHODS: Susceptibility testing by broth microdilution was performed on 30 MRSA clinical isolates. For four of these isolates, the presence or absence of mutations in the QRDR was characterized. Resistance selection was performed on these four isolates by spreading cells on drug-containing agar plates followed by incubation for 48 h. Resistance frequencies and mutant prevention concentrations (MPCs) were calculated for each; PCR amplification and sequencing were performed using standard methods to characterize mutations in the QRDR. Growth rate analysis was performed and relative fitness was determined. RESULTS: Delafloxacin demonstrated potent in vitro activity against this set of MRSA isolates, with MICs of 0.008-1 mg/L and an MIC(50) and MIC(90) of 0.03 and 0.5 mg/L, respectively. Spontaneous delafloxacin resistance frequencies for the MRSA strains were 2 × 10(-9) to

The current-voltage characteristics (I-V) of Au-n-type InP Schottky diodes and MIS Schottky diodes fabricated by multipolar plasma oxidation are measured at various temperatures in order to investigate the applicability of a newly proposed conductance technique. Experimental data are analysed on the basis of this technique relating the series resistance Rs and the ideality factor n to the conductance G=dI/dV, and leading also to the determination of the saturation current Is. The values obtained for the temperature coefficient of the Schottky barrier height alpha were -1.3*10-4 eV K-1 and 4.1*10-4 eV K-1, depending on the substrate, and the ideality factors were around 1.07. The Richardson plot ln(Is/T2) against (1/T) is well fitted to a straight line (T is the temperature). It is shown that, when some conditions discussed in the paper are fulfilled; the method can be applied to MIS Schottky diodes. In this case the apparent barrier height phi Bh increases linearly with increasing temperature and the electron tunnelling factor is estimated to be 16.

To the Editors: Acute exacerbations (AEs) are now recognised as a frequent and severe complication of idiopathic pulmonary fibrosis (IPF). In a large series, 1- and 3-yr incidences were 14.2% and 20.7%, respectively [1]. New diagnostic criteria were published in 2007 [2]. The pathogenesis of these episodes remains unknown, although invasive procedures have been described as possible triggers. Prognosis is poor, with a short-term mortality rate of 45–85%. There is no consensus regarding treatment, as no published study has compared the efficiency of different treatment regimens, and treatment often differs between patients within a given study [1–4]. Since 2005, exacerbations of IPF identified in our referral centre (Centre Hospitalier Regional de Lille, Lille, France) have been treated with pulses of methylprednisolone followed by pulses of cyclophosphamide [5]. The main goal of the present retrospective study was to evaluate the mortality of exacerbations of IPF treated with this regimen. Following admission for aggravation of dyspnoea, a series of tests were run to determine diagnosis and functional impairment. When an exacerbation of IPF was diagnosed, patients were treated with a methylprednisolone pulse (1,000 mg) at days 1–3 and on day 4 placed on an escalating regimen of cyclophosphamide with an initial dose of 500 mg intravenously [5]. The dose of cyclophosphamide was increased by 200 mg every 2 weeks, provided the total white blood cell count remained at >3,000 cells·mm−3. The maximum single administered dose was 1,500 mg of cyclophosphamide. The diagnosis of IPF was reassessed for the purpose of this study …

Association of the bone-forming osteoblasts (OBs) and vascular endothelial cells (ECs) into a biomaterial composite provides a live bone graft substitute that can repair the bone defect when implanted. An intimate functional relationship exists between these cell types. This communication is crucial to the coordinated cell behaviour necessary for bone development and remodelling. Previous studies have shown that direct co-culture of primary human osteoprogenitors (HOPs) with primary human umbilical vein endothelial cells (HUVECs) stimulates HOPs differentiation and induces tubular-like networks. The present work aims to test the use of human bone marrow stromal cells (HBMSCs) co-cultured with human endothelial progenitor cells in order to assess whether progenitor-derived ECs (PDECs) could support osteoblastic differentiation as mature ECs do. Indeed, data generated from the literature by different laboratories considering these co-culture systems appear difficult to compare. Monocultures of HUVECs, HOPs, HBMSCs (in a non-orientated lineage), PDECs (from cord blood) were used as controls and four combinations of co-cultures were undertaken: HBMSCs-PDECs, HBMSCs-HUVECs, HOPs-PDECs, HOPs-HUVECs with ECs (mature or progenitor) for 6 h to 7 days. At the end of the chosen co-culture time, intracellular alkaline phosphatase (ALP) activity was detected in HOPs and HBMSCs and quantified in cell extracts. Quantitative real-time polymerase chain reaction (qPCR) of ALP was performed over time and vascular endothelial growth factor (VEGF) was measured. After 21 days, calcium deposition was observed, comparing mono- and co-cultures. We confirm that ECs induce osteoblastic differentiation of mesenchymal stem cells in vitro. Moreover, HUVECs can be replaced by PDECs, the latter being of great interest in tissue engineering.

The aim of this study was to evaluate the functional outcome of Brilliant Blue G (BBG) and the staining properties in macular surgery.BBG was applied during vitrectomy for macular holes (n = 21) or epiretinal membranes (n = 18) in a prospective, non-comparative consecutive series of patients (Brilliant Peel®; Fluoron® GmbH, Neu-Ulm, Germany). Before and after surgery all patients underwent a complete clinical examination including measurement of best corrected visual acuity and intraocular pressure, perimetry, fundus photography and optical coherence tomography.Vitrectomy was performed in combination with a cataract operation in 14 patients. All macular holes were closed successfully. Visual acuity was in average 0.16 preoperatively in macular hole cases and increased up to 0.4 after 6 months. Visual acuity of patients with epiretinal membranes changed on average from 0.3 to 0.45 after 6 months. The retina thickness in patients with epiretinal membranes was initially 402.6 µm according to the OCT and 304.7 µm after 6 months postoperatively. No toxic effects attributable to the dye were noted during patient follow-up, especially all perimetry tests were normal.Brilliant blue provides a sufficient and selective staining of the ILM. No retinal toxicity or adverse effects related to the dye were observed in this study. The long-term safety of this dye will have to be evaluated in larger patient series and a longer follow-up.

This paper describes the interfacing of the simulation software DSS/2 and the optimization program OPTDES in order to build a PC environment for simulation and parameter estimation of dynamical systems with distributed parameters. The efficiency of these FORTRAN software tools is illustrated by a furnace modelling study. The nonlinear partial differential equations of the model are discretized by the finite-difference method and the orthogonal collocation on finite elements, and the simulation results are compared. It is shown that the use of differential-algebraic solvers to handle the boundary conditions and an effective grid point selection lead to a significant reduction of the result equations. The unknown model parameters are estimated from experimental data by minimizing an output least-square error criterion with a hybrid sequential quadratic programming-generalized reduced gradient algorithm.

Reactive sputtering is now widely used for the elaboration of Ti-N coatings. For applications in mechanics, good reliability of the coating properties is necessary and thus careful process control must be achieved. This requires a complete characterization of the deposition process. We intend to fulfil this demand in the case of TiN coating elaboration by reactive sputtering of a hot cylindrical titanium cathode in an argon-nitrogen-hydrogen plasma. With the working pressure (about 5 Pa) used in our reactor, two major problems arise: impurity contamination and instabilities connected with target poisoning. We have studied the influence of the target-to-substrate distance and nitrogen flow rate on the chemical and phase composition of the elaborated coatings. Optical emission spectroscopy is used to establish the gaseous phase diagnostics. All these results are successfully compared with those of a mathematical model.

Plasma treatments are playing an increasing role in microelectronic technology. The present paper deals with the deposition of Ta 2 O 5 dielectric layers on n-InP by multipolar plasma technology for the fabrication of MISFET (metal-insulator-semiconductor field effect transistor) structures. Damage induced by plasma exposure is one of the major problems in such fabrication. Therefore the working conditions (sample bias, discharge power and oxygen pressure) have to be optimized so as to limit the ion energy on the substrate during treatment. After plasma treatment the oxide films are stabilized by post-annealing at 200°C in an N 2 atmosphere. The oxide thickness is determined by ellipsometric measurements. The growth condition of the dielectric in the plasma is also related to the basic electronic and interface properties of InP-oxide-Au structures using static I-V , dynamic C-V and ESCA (electron spectroscopy for chemical analysis) measurements. Equivalent Schottky barriers as high as 0.87 eV are obtained.

The dynanlic behavior of an experimental multizone electrical fumace is described by nonlinear partial differential equations. On this basis, a nonlinear distributed observer of the load temperature profiles is designed. The resulting observer equations are discretized by orthogonal collocation on finite elements and implemented on-line on a PC. The observer shows very good properties: easy tuning, robustness and small computer resources. Some experimental results and computer simulations are presented and discussed. Moreover, a comparison is petfonned between the observer and a distributed extended Kalman filter, including on-line perfonnances and computational implementation aspects. It is shown that the observer requires less computational effort for sinlilar perfomances.

The dependence on bias of the photoluminescence (PL) intensity of Schottky diodes and oxidized structures obtained by multipolar plasma oxidation of n-InP was compared. For the oxidized structures, the calculated PL intensity curve remained well below the experimental results. This fact is attributed to a limited swing of the surface Fermi level of the semiconductor. The flat band voltage was also deduced from PL measurements, and the corresponding barrier height φ B = 0.4 eV is in good agreeemnt with the value inferred from current-voltage results for the Schottky diode. For the oxidized structures there was a difference in φB deduced using the two methods. The presence of the thin oxide layer must at least be considered to explain these different apparent barrier heights.