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INTRODUCTION Wolfram syndrome is a rare autosomal recessive genetic disease characterized by diabetes insipidus, diabetes mellitus, optic atrophy and deafness. A neurodegenerative syndrome is usually associated, including cerebellar ataxia. A few cases of central apnea have been reported in the literature. Here, we report a case of Wolfram syndrome with respiratory symptoms that led to the discovery of central apneas as well as complicated and delayed weaning in an intensive care unit (ICU). OBSERVATION The patient is a 39-year-old woman diagnosed with Wolfram syndrome who was admitted to an ICU for septic shock. She experienced difficult weaning before central apneas were observed while spontaneous ventilation was being attempted. After two extubation failures, cerebral MRI was performed and revealed parenchymatous atrophy of the posterior brain fossa involving the cerebral trunk, cerebellar peduncles, as well as both cerebellum hemispheres and the cerebellar vermis. Even after the patient was tracheotomized, central apneas persisted when the patient breathed spontaneously with her tracheotomy, necessitating nocturnal ventilation. CONCLUSION While central apneas Wolfram syndrome remain rare, they should be systematically investigated due to their association with severe morbimortality.

Introduction Les societes savantes preconisent de cibler un volume courant de 8 a 10 mL/kg de poids ideal theorique pour l’adaptation des niveaux de pressions a utiliser en ventilation non invasive au long cours chez les patients insuffisants respiratoires chroniques (IRC), sans que cette cible n’ait ete confirmee par des essais randomises. A travers une cohorte prospective de patients ventiles au long cours, l’objectif de notre etude est de decrire le Vt (en mL/kg de poids ideal theorique) obtenu en se basant sur la correction du bilan gazeux arteriel et de l’oxymetrie nocturne. Methodes Nous avons inclus les patients issus de la cohorte prospective de l’Institut de recherche en sante respiratoire de 2009 a 2018. Pour etre inclus, il fallait etre âge de plus de 18 ans et avoir donne un consentement ecrit. Les etiologies d’insuffisance respiratoire chronique ont ete separees en 4 groupes : les BPCO, les BPCO obeses, les SOH et les neuromusculaires. Les patients SLA ont ete exclus de l’analyse. Le volume courant estime a ete recueilli sur les donnees machines lors de la visite de reevaluation 4 a 6 mois apres l’instauration de la VNI. Resultats Au total, 224 patients ont ete inclus dans notre etude. Sur l’ensemble de la cohorte, 44,6 % des patients ont un Vt superieur a 10 mL/kg, 30,4 % un Vt compris entre 8 et 10 mL/kg et 25,0% inferieur a 8 mL/kg (representes en majorite par les neuromusculaires). Le Vt moyen est de 9,9 mL/kg sur l’ensemble de la cohorte avec une variation selon les etiologies: le Vt est statistiquement plus bas chez les patients neuromusculaires a 7,8 ± 1,9 mL/kg que les patients SOH a 10,4 ± 2,7 (p Conclusion Dans le cadre d’une ventilation non invasive avec pour objectif l’obtention d’un volume courant cible (en mL/kg de poids theorique), il semble pertinent d’adapter cet objectif selon l’etiologie de l’insuffisance respiratoire : 8 mL/kg pour les patients neuromusculaires, 9 mL/kg pour les patients BPCO, > 10 mL/kg pour les patients SOH et les patients BPCO obeses.

The probabilistic data association method has been successfully used for tracking targets in the presence of source uncertainty and measurement inaccuracy. Using this technique, the problem of maneuvering-target tracking is considered. A description is given of three adaptive methods which are intrinsically different for tracking single and/or multiple targets. These methods are called the adaptive control probabilistic data association filter, the adaptive joint probabilistic data association filter, and the adaptive control joint probabilistic data association filter. They estimate the state of each target in a cluttered environment for abrupt or slow changes of the target parameters. >

The efficacy of radioimmunotherapy (RIT) with beta emitters has been clinically demonstrated in the treatment of refractory forms of lymphoma. Alpha-emitting radionuclides with a short half-life are also good potential candidates for RIT directed at tumor targets easily accessible to radioimmunoconjugate molecules and small enough to benefit from the short range of alpha particles (100 microm). The purpose of this study was to demonstrate the feasibility of ex vivo purging of multiple myeloma-invaded bone marrow. Tumor cells were targeted by a specific monoclonal antibody (B-B4) coupled to 213Bi by a chelating agent (pentaacetic triamine diethylene p-aminobenzyl acid). The efficacy of alpha-RIT was assessed in vitro by analysis of thymidine incorporation, cell mortality, apoptosis of myeloma cells, and the study of nonspecific irradiation of hematopoietic cell lines not recognized by B-B4-pentaacetic triamine diethylene p-aminobenzyl acid immunoconjugate. High dose-dependent cell mortality of myeloma cells was found with radiolabeled B-B4, and this mortality was total at 30 kBq/10(5) cells. Cells were found in apoptotic state at rates of up to 40% for a dose of 7.4 kBq/10(5) cells. Nonspecific mortality was low compared with specific mortality (up to 1%).

We examine a new robust control procedure in order to ensure the best trade-off performance/parametric robustness. This study extends the research performed into an analysis method called PRABI (parameter robust analysis Bayesian identification). Its basic idea was the close relationship between quality of fictitious parametric Bayesian identification in closed-loop and stability robustness against variations of inherent parameters. The algorithm detailed below generalizes the concept in parametrizing the synthesis step for the study of performance robustness. Robust control design of a flexible system is demonstrated to prove the relevance of the theoretical methodology, which is easy to implement.

In this paper, we deal with the problem of designing a feedback controller for a linear discrete time plant that is liable to perturbations of a physical parameter vector. The new robustness measure is based on the link between the poorest quality of the closed loop parameter identification and the performance and stability robustness for regulators. Reversely, this means that the better the robust control, the worse the closed loop identification quality. Our first objective is not to identify unknown parameters but to derive an analytical expression of the covariance matrix of a bayesian estimator. We obtain then the controller gain matrix which would minimize this quality if the identification algorithm was implemented. Important relationships between PRLQG method and this new technique called PRCBI are obtained and it is shown that the PRCBI is a generalization of the PRLQG method. Furthermore a flexible structure application shows that the best results are achieved using the PRCBI method.

This communication presents the design of robust digital laws for the attitude control of a launcher, and the singular value analysis of stability effects of the structural couplings between axes. In a first stage control laws on each of the three axes are defined. The retained synthesis method is LQG-LTR (Loop Transfer Recovery). Monoaxis control laws with input robustness properties are obtained, insuring the required performances during whole flight. In a second stage, the effects of the couplings on the performances of those control laws are investigated. The robustness of the monoaxis laws regarding coupling is analyzed through the computation of minimal and maximal singular values of the sensitivity matrix as a function of coupling rate. In order to improve this robustness other LQG criteria are considered. The bending modes act on measures, so their introduction in the criteria can been made systematic by a technique of know robustness qualities : that is to add to the weighting matrix Q a term ρHTH, where H represents the output matrix of the state representation. By adjusting the value of ρ, a compromise between needed robustness and desired performances can be achieved. The interest of this study is to demonstrate, on a rather complex system, the efficiency of the LQG-LTR techniques in the design of digital robust control laws. It leads to the conclusion that the monoaxis synthesis of attitude control for a nonsymmetrical launcher is valid if associated with multidimensional analysis of robustness and stability.

En régime permanent, un convertisseur statique peut assurer le transfert optimal de puissance entre une source de puissance finie et un récepteur. L'étude de ce transfert en régime dynamique fait apparaître une interaction entre le récepteur et le générateur qui provoque des réponses non minimales de phase dues à la présence de zéros à partie réelle positive dans la fonction de transfert du système. Afin d'optimiser le transfert dynamique de puissance, les auteurs proposent des critères de choix des paramètres de structure, du nombre de degrés de liberté et des lois de commande de convertisseurs qui garantissent des réponses minimales de phase. Ensuite, une compensation par retour d'état permet d'assurer un transfert optimal de la puissance entre le générateur et le récepteur.

This paper deals with a suboptimal algorithm for the simultaneous state and parameter identification obtained by incorporating several generalizations into Bar-Shalom's approach (1972). Those include multi-input, multi-output systems, unknown process and measurement noise statistics and partial process noise. The resulting problem is too large and complex to obtain the solution by single-level minimization techniques and hence a two-level algorithm is proposed. It turns out that certain submatrices of the system are unidentifiable and hence an output-error stage is added on to the algorithm to identify these submatrices. The resulting hybrid algorithm is shown to be computationally efficient and is applicable to the class of problems characterized by a non-singular covariance submatrix of the process noise. Finally, an optimal scheme is proposed for the same class of problems.

The simultaneous state and parameter estimation problem for a linear discrete-time system with unknown noise statistics is treated as a large-scale optimization problem. The a posterioriprobability density function is maximized directly with respect to the states and parameters subject to the constraint of the system dynamics. The resulting optimization problem is too large for any of the standard non-linear programming techniques and hence an hierarchical optimization approach is proposed. It turns out that the states can be computed at the first levelfor given noise and system parameters. These, in turn, are to be modified at the second level.The states are to be computed from a large system of linear equations and two solution methods are considered for solving these equations, limiting the horizon to a suitable length. The resulting algorithm is a filter-smoother, suitable for off-line as well as on-line state estimation for given noise and system parameters. The second level problem is split...

In a first part of the study, we shall give a description of the mathematical model of the two kinds of metallurgic furnaces of reheating, that is : - the impelling furnace where the thermic exchanges are unidirectional (continuous sheet). - the furnace with stringers into which a given space is kept between two products. . The numerical methods analyzing the thermic process by a solution of the equations of the model are then described. The second part of the study is devoted to the identification of the parameters of the model (thermal conductivity and heat capacity of the metal) from a punctual observation of the phenomena (two measures on the surface and in the middle of the metal. For this purpose, some methods of non-linear p ogramming are used and then analyzed critically. The last part deals with “the optimization” of the furnaces operating under steady-state conditions (homogeneous filling), in the case of the two criterion of optimality (energizing one or that of the quality of the metal) and constraints of “rolling” of the metal.

The notion of truncated function is used as a new approach to establish controllability criteria for stationary linear multivariable systems. The method presented provides a simple technique to test the controllability of a system represented by its inputs and initial conditions transfer matrices. In addition, the formulation of the problem leads to a very straightforward method for deriving optimal control laws for certain classes of minimum fuel and minimum time control problems.

A very general and numerically quite robust algorithm has been proposed by Sastry and Gauvrit (1980) for system identification. The present paper takes it up and examines its performance on a real test example. The example considered is the lateral dynamics of an aircraft. This is used as a vehicle for demonstrating the performance of various aspects of the algorithm in several possible modes.

This paper deals with the problem of synthesising a control scheme well fitted to the long-range mission of the station keeping of a synchronous, flywheel yaw-stabilized communication satellite. This particular type of mission imposes drastic constraints upon on-board equipment and its technology: a minimum number of attitude sensors should be used, while stringent conditions are imposed upon the precision of the attitude by the communication equipment’s operation. Furthermore, the fuel consumption should be kept to a minimum, whereas the propulsive equipment should be as light and reliable as possible.

Interface problems related to adapting available 3-phase inverter designs between a photovoltaic array and an AC motor generator without a battery, have been partly solved. However, instability and nonminimal phase responses have been observed on the experimental array. So, the contributing research that will be described in the paper is (i) modelling the photovoltaic system by means of state representation, (ii) studying stability and nonminimal phase responses with the control functions and (iii) describing a method to compute optimal control functions. If the control function is the amplitude stator frequency, the system may be unstable. Replacing the stator frequency control function by a rotor frequency allows the system to remain stable. The phase of the transient response of the speed state variable always is non-minimal when the voltage cell is lower than the optimal voltage cell.

A theory of control in state space is applied to an electrotechnical process associating an asynchronous motor and a static convertor. The object is to realise current regulation for an induction machine. The process is inherently nonlinear and a classic regulator cannot ensure the same performances over all the operating range. A mathematical model of the process to be controlled is presented and a compensator determined. An observer and the desired regulation are chosen through the imposition of the system dynamics in a closed loop.