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A main difficulty in practical implementation of optimal control theory for distributed systems lies in the computational complexity, especially in presence of constraints. Here we are dealing with an optimal control problem (in a minimal time) of a distributed system. The control problem is formulated as a moment problem whose solution gives an algorithm which makes it possible to determine the optimal control law and to compute it in terms of initial and desired states. After recalling the results of the L problem of moments, an hybrid simulation of the control problem for a diffusion equation is treated.

Les anevrysmes arleriels peripheriques sont une complication classique des endocardites infectieuses. Cette complication reste cependant assez rare. Ils apparaissent comme une complication tardive de la maladie, exceptionnellementcomme signe d'appel. Degeorges, etudiant 300 dossiers, ne le signale jamais. A notre connaissance, seuls Merry et coll. ont rapporte l'observation d'un malade chez qui une endocardite a staphylocoques a ete revelee par l'apparition d'un purpura localise et d'un anevrysme poplite mycotique. Cette rarete nous autorise a relater le cas d'un homme dont la maladia a commence de facon semblable.

The characteristics of an ion beam issued from a hydrogen plasma have been studied. This plasma is obtained by means of a high‐frequency discharge set under conditions of resonance. This resonance is obtained by inductively exciting the discharge in a transverse static magnetic field (perpendicular to the axis of the vessel). The resonance, of which we give the characteristics, permits a considerable increase in the ionization degree, and is therefore of interest as regards to ion sources. The beam of particles extracted from this discharge in resonance is studied by means of a magnetic analyzer. The energy distributions of the various ions consist of two parts. A comparative analysis of the characteristics of the beam, with and without resonance, shows that this resonance improves the properties of the system. In particular, for the H1+ ion, the energy dispersion is reduced to 25 eV and its proportion in the beam reaches 85%. This resonance proves to be a convenient and very simple means to obtain an H1+...

Observation d'un phenomene de resonance electronique cyclotronique sur l'harmonique 2 dans le plasma d'hydrogene d'une source H. F. en couplage inductif, le champ magnetique etant transversal.

This study deals with dynamic pattern recognition, one of the most important functions of perception. So, we may consider our system as a simulation of the nervous system. Our experiments allow us to think that our system may lead to a concrete realization; otherwise, it would be able to explain some neurophysiological processes.

In three cases collected among subjects with atrial anatomical lesions (two cases of "sinus disease" with partial atrial paralysis and one traumatic lesion of the right atrium in a WPW syndrome), atrial pacing demonstrated a considerable increase of the interval between stimulus and atrial response or intra-atrial Luciani-Wenckebach periods, for slightly increased pacing rates. Conduction changes into the right atrium explain apparently paradoxical variations of the degree of pre-excitation under pacing, in the case of Wolff-Parkinson-White syndrome.

Results of arterial surveys on the basis of renal arteriograms in 100 consecutive unselected and hospitalized cases of lone arterial hypertension of the adult. Abnormal polar arteries with direct branching from the aorta were observed in 52 cases, combined with a stenosing or parnechymatous arterial anomaly in 7, quite isolated in 45 cases (61.8 percent of 73 cases). The very great incidence of abnormal polar arteries is a fundamental epidemiological datum of lone arterial hypertension of the adult.

A female patient of 22 with major hypertension was operated upon for a dyspalastic diaphragm stenosis of the right renal artery; she had otherwise a left lower polar aortic artery. The histological study was under-taken on four comparative biopsy specimens. In the aortic polar artery territory, the signs of atrophic dysgenesis were demonstrated: rarefaction and sclerosis of the glomeruli, sclerosing intretitial infiltration. They reproduce exactly the lesions of immature kidneys described by Marshall.

A syndrome of obstacle to the outflow of the left ventricle was found in a woman with atrio-ventricular block with narrow ventricular complexes. A tuberculoma of the intar-atrial septum was responsible both for the obstacle to left ventricular ejection and for the block which was found to be proximal on microscopic examination.

Fifty one patients from different surgical units, hence anesthetized by different anaesthesists, underwent reinterventions in abdominal surgery. The indications for the first intervention essentially involved the supra-mesocolic region of the abdomen (62 out of 100 cases). The operative risk during the first intervention was on the average 18 pour cent. The protocol of the first anaesthesia which was known in 42 cases, was of the narco-ataralgestic type. The date of the return to the operation table varied from 1 to 60 days. The state of the patients was in general catastrophic (organic renal failure, acute respiratory failure). Here again the anaesthesia was of the narco-ataralgesic type but the choice of drugs varied depending on the patients' state. However non significant difference was noted in the average hourly drug consumption between the two interventions. Apart from one circulatory arrest during induction, in one patient with hemorrhagic shock, no death was attributable to the anesthetic technique. The authors, using these findings, attempt to pick out a practical line of behaviour.

Analysis of a further series of 125 consecutive unselected adults who were admitted to hospital with hypertension has advanced the study of arterial abnormalities and parenchymal hypoplasia, as demonstrated by selective renal arteriography, further in the direction of the parenchyma. An index of arterioparenchymal thinning is described. The authors list the features and incidence of polar arteries arising from the aorta (46%), polar arteries of non-aortic origin (31%), stenosing dysplasia (26%) and other arterial malformations, as well as biapical hypoplasia (67%), monofocal hypoplasia (37%), and the main types of renal dysgenesis (30%) which they found. The incidence of these abnormalities confirms the previous study of polar arteries arising from the aorta, and gives much more extensive information on the topic of parenchymal hypoplasia in so-called essential hypertension in the adult.

Nineteen patients presenting cardiovascular distress were treated with dopamine. For seventeen of these, the accident occurred immediately after cardiac surgery. Dosages varied from 1 to 15 mug/kg/min and the duration of treatment from 10 minutes to three days. The efficacy of the treatment was judged according to the clinical and hemodynamic improvement of the cardio-circulatory function and the increase in urinary output. There were 15 favourable results. The positive effects of the dopamine seem to be limited in certain patients by the appearance of a cyanosis testifying to a rise in vascular resistances which increases the left auricular pressure and limits the inotropic effect. In these cases, isoproterenol or a combination of both isoproterenol and dopamine gives better results.

A histological study by the method of seriated sections in one case of "double-outlet left ventricle" made it possible to confirm and to describe the embryology of the nodal-His junction: not only the atrio-ventricular node (AV N) but also the His bundle (H) have a double origin, atrial and ventricular. Fusion of these two buds, inexistant in the "lone ventricle" is certainly imperfect. Two macroscopically normal hearts provided examples of nodal buds in one case, of a persisting cleft between the two His buds in the other.

The suction electrode makes it possible to record the monophasic action potentials (MAP) of the heart in situ. The technical characteristics of the tripolar electrode which we use are described. The O phase of the MAP is more prolonged than that of the intracellular action potential, but makes it possible to demonstrate the time of arrival of the activation wave in front of the exploring electrode. The phase 1-2 and the phase 3 have their characteristic contour in the right atrium and ventricle. The duration of repolarization makes it possible to assess the refractory period of different parts of the atrial and ventricular myocardium. The relatively simple and harmless method of recording of the monophasic action potentials by the endocardial route, both in the animal and in man, widens our investigation field of electrophysiology applied to the study of arrhythmias, of the repolarization disturbances and of the drug influences on the cell activity.