Showing papers by "Paris Descartes University published in 1984"

Probe with variable geometry for measuring the radial strains in a sphincter of a living organism

Abstract: A probe for studying the visco-elastic behavior of sphincters of living organisms is comprised of an expansible head formed by three articulated groups disposed radially at 120° intervals about a central axis. Each of the articulated groups is composed of a cross-piece which interconnects a rigid member, carrying a strain gauge on its outer surface, to the central axis. The cross-pieces are articulated at one end about the opposite ends of the rigid member and are articulated at the other end about two blocks which are carried by the central axis. The cross-pieces are constructed such that rotation of the central axis causes the distance between the rigid elements and the central axis to vary. A flexible shaft couples the central axis to a motor.

Hydrocephaly treatment device including a variable impedance filter

Abstract: To treat hydrocephaly, an intracranial catheter is implanted in the head. It is connected to a tube fitted with a non-return valve and serves to divert the flow of cephalo-rachidian liquid to the peritoneum or to the right auricle of the heart. In accordance with the invention a hydraulic filter of non-linear variable impedance is connected in the tube in series with the valve. The filter maintains an average flow rate of the cephalo-rachidian liquid close to the physiological flow rate, but prevents sudden rushes of fluid flow, thereby permitting the intracranial pressure to vary in the short term in the normal manner over a characteristic period of about one second, while preventing said pressure from rising slowly in the long term, e.g. over a characteristic period of about one minute. This is done by a bead (160) which is housed in a cavity (161) extending between a proximal orifice (111) and a distal orifice (136). The distal orifice constitutes a leaky valve seat for the bead.

Device with a variable impedance filter for the treatment of hydrocephalus

Abstract: Pour le traitement de l'hydrocephalie, on implante un catheter intracrânien, qui est connecte a une tubulure munie d'une valve, et permettant la derivation de l'ecoulement du liquide cephalo-rachidien vers le peritoine ou l'oreillette droite du coeur. For the treatment of hydrocephalus, is implanted intracranial catheter, which is connected to a pipe provided with a valve and allowing the bypass of the flow of cerebrospinal fluid into the peritoneum or right atrium of the heart. Selon l'invention, cette tubulure est munie, en serie sur la valve, et dans son trajet vertical, d'un filtre hydraulique a impedance variable passe-bas. According to the invention, this pipe is provided in series with the valve, and in its vertical path, a hydraulic variable filter low-pass impedance. Une bille (160) est logee dans une cavite (161) definie entre un orifice proximal (111) et un orifice distal (136) formant siege de soupape avec la bille (160), tout en permettant un debit de fuite choisi. A ball (160) is housed in a cavity (161) defined between a proximal port (111) and a distal orifice (136) forming the valve seat with the ball (160), while allowing a leakage rate chosen. Les variations rapides de la pression intracrânienne ne sont pas perturbees; The rapid changes in intracranial pressure are not disturbed; par contre, ce dispositif empeche une augmentation lente de pression, par le maintien d'un debit moyen de liquide cephalo-rachidien. by cons, this device prevents a slow increase in pressure, by maintaining an average flow rate of cerebrospinal fluid.

De La Synchronie Dynamique à La Diachronie

Abstract: RESUMECertains comparatistes s'attachent a expliquer les changements dont ils relevent la trace dans les langues avec lesquelles ils operent. Ils restent cependant peu enclins a rechercher, dans les etats de langue directement accessibles, la confirmation de leurs hypotheses. Rares meme sont les etudes ou l'on s'efforce de restituer un continuum pour chacun des changements releves. La conception d'une synchronie dynamique a conduit a examiner le changement dans son devenir par la prise en consideration de reactions differentes des informateurs selon leur âge au moment de l'enquete. Elle permet ainsi une meilleure comprehension du fonctionnement des langues et des evolutions qui en resultent. Elle devrait conduire, d'une part, a une pratique plus responsable dans le champ des recherches diachroniques et, d'autre part, au retablissement de l'unite a l'interieur de notre discipline.SUMMARYSome comparatists try to explain the changes whose results they observe in the languages with which they operate. But they are still reluctant to look for information and support for their hypotheses in directly accessible linguistic stages. Even attempts to reconstruct a continuum for each of these changes on record remain exceptional. The conception of a dynamic approach has led to the study of processes by observing the informants' diverging reactions on account of their age at the time of the investigation. The result is a better understanding of the functioning of language and the resulting evolution. The method should lead, on the one hand, toward a more responsible approach in the field of diachronic research, and, on the other, to restoring the unity of our discipline.ZUSAMMENFASSUNGEinige vergleichende Sprachforscher versuchen die Veranderungen zu erklaren, deren Ergenisse sie in den Sprachen beobachten, die sie be-handeln. Sie zeigen bisher jedoch wenig Neigung, Erklarungen oder Bestatigungen ihrer Hypothesen in direkt zuganglichen Sprachzustanden zu suchen. Selbst Versuche, ein Kontinuum fur jeden einzelnen fest-gestellten Wandel herzustellen, sind selten geblieben. Das Konzept eines dynamischen synchronischen Herangehens hat zum Studium von Pro-zessen gefuhrt, indem die abweichenden Reaktionen der Informanten unter Bezugnahme auf ihr Alter zu Zeit der Untersuchung notiert worden sind. Das Ergebnis hat zu einem besseren Verstandnis sprachlicher Funktionen gefiihrt und daraus folgenden Wandlungen. Eine solche Methode sollte einerseits zu einem verantwortung sbewussteren Herangehen im Bereich der diachronischen Forschung, anderseits aber auch dazu fuhren, die Einheit der Wissenschaft von der Sprache wiederherzustellen.