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This article reports on the design, development, and validation of advanced prototype 2 MVA generation equipment [i.e., naval package (NP)] for a shipboard medium-voltage dc integrated power system (MVDC IPS). The generation equipment is based on an ultrahigh-speed 22,500-r/min 12-phase alternator, which feeds an ac/dc power electronics converter comprising four diode rectifiers and four insulated-gate bipolar transistor (IGBT) choppers. The prototype realization constitutes a follow-up of a previous NP version employing a wound-field 6,300-r/min alternator feeding noncontrolled ac/dc converters. The major technical challenges faced in the design and development of the advanced NP prototype are outlined in this article, taking the previous lower-speed version as a technology reference. The system performance, as determined by the testing campaign, and lessons learned for future studies are addressed.

Resume Propos et objectifs L’hypertension arterielle pulmonaire (HTAP) represente l’une des graves complications menacant la vie des patients atteints de sclerodermie systemique (ScS). En France, les modalites de depistage et de gestion de l’HTAP associee a la ScS ne sont pas encore bien codifiees et ne font pas l’objet d’un consensus. Nous avons mene une enquete aupres des medecins inscrits sur la liste du Groupe de recherche francais sur la sclerodermie (GRFS) pour faire un etat des lieux de la prise en charge de l’HTAP associee a la ScS. Methodes Nous avons envoye en 2002 un questionnaire a 160 medecins membres du GRFS, pour evaluer l’epidemiologie et la clinique des patients ScS, ainsi que les modalites de depistage et de gestion de l’HTAP chez ces patients. Resultats Quatre-vingt-huit medecins dans 71 centres ont repondu a ce questionnaire. Chaque centre suivait en moyenne 33 ScS, avec une repartition globale de 53 % de ScS limitees et de 47 % de ScS diffuses. Ces medecins voyaient en moyenne 5 nouveaux cas de ScS par an. Les patients leur etaient adresses par les confreres de ville (53 %) ou d’hopital (47 %). Le nombre moyen de patients ScS + HTAP etait de 5,1 par medecin (1,5 nouveaux patients ScS + HTAP par an). La quasi-totalite (65/67) des centres ayant repondu depistaient systematiquement l’HTAP chez les patients ScS, par echo-Doppler cardiaque, en moyenne tous les 1,3 ans. La majorite (41/63) des centres collaboraient, pour la gestion de leurs patients atteints d’HTAP, avec un service specialise. Environ un tiers de ces centres traitaient ces patients par inhibiteurs calciques (82 %) et/ou prostacycline (90 %). Le suivi des patients se faisait par l’echographie Doppler cardiaque dans tous les cas. La majorite des medecins (72 %) etaient interesses par un protocole de recherche sur ce sujet et auraient pu chacun y inclure 4 patients, soit un total de 160. Conclusion L’HTAP, complication severe de la ScS, est depistee par les medecins du GRFS avec l’echographie cardiaque a une frequence se rapprochant des recommandations de l’OMS (1,3 versus 1 fois/an).

This paper reports on the design, development and validation of an advanced prototype 2MVA generation equipment (Naval Package) for a shipboard Medium-Voltage DC integrated power system. The generation equipment is based on a ultra-high-speed 22500-rpm 12-phase alternator which feeds an AC/DC power electronics converter composed of four diode rectifiers and four IGBT choppers. The prototype realization constitutes a follow-up of a previous Naval Package version employing a wound-field 6300-rpm alternator feeding non-controlled AC/DC converters. The major technical challenges faced in the design and development of the advanced Naval Package prototype are outlined in this paper taking the previous lower-speed version as a technology reference. The system performance highlighted by the testing campaign are finally addressed along with the lesson learnt to be capitalized for future developments.

Resume Propos. – L'ulcere de Mooren (UM) est une ulceration corneenne peripherique inflammatoire chronique avec depots conjonctivaux d'immunoglobulines d'etiologie indeterminee. Cette pathologie rare serait due a un processus auto-immun cellulaire et humoral. Elle est souvent rebelle, avec un risque de perforation corneenne qui met en jeu le pronostic anatomique de l'œil. Lorsque les traitements corticoides et chirurgicaux procurent des resultats mediocres, la chimiotherapie a ete proposee, mais ses effets secondaires en limitent l'usage. Methode. – Suivi longitudinal de trois patients atteints d'UM rebelles aux traitements conventionnels, traites par bolus intraveineux mensuels de 1 g de cyclophosphamide (Cy). Resultats. – Un patient de 24 ans, presentant un UM perfore de l'œil gauche malgre une keratoplastie lamellaire associee a une corticotherapie intraveineuse, a pu cicatriser sa cornee au terme de 9 mois de traitement par Cy. Un patient de 50 ans presentant un UM de l'œil gauche, rebelle, a recu durant 20 mois du Cy qui a permis une cicatrisation corneenne. Un patient de 70 ans, presentant des UM bilateraux avec une lesion corneenne preperforative de l'œil droit, a obtenu la cicatrisation apres resection conjonctivale et 4 mois de traitement par Cy. Nous n'avons pas note d'effets secondaires avec ce mode d'administration contrairement aux donnees de la litterature sur les chimiotherapies orales. Conclusion. – Nous rapportons l'efficacite du traitement des UM rebelles aux traitements conventionnels par Cy en bolus intraveineux mensuels de 1 g. Ce traitement pourrait etre propose dans les cas d'UM rebelles.

This paper presents a critical review of the evolution that electric generators installed on board all-electric modern cruise liners have undergone in the past decade. The aim is, through the deep understanding of the real operating conditions of a passenger fleet, to capture evolution trends and to project them into a near future scenario. This scenario is to constitute a valuable tool to ascertain which improvements are to be considered beneficial for the application, thus providing a competitive advantage to suppliers and a valuable asset for ship-owners. Such future scenario includes new generating trends for conventional (Medium Voltage AC) as well as a sight into future new Integrated Power Systems based on Medium Voltage Direct Current technologies.

In this paper, a demonstrative technological implementation of a shipboard 2.15 MVA generation system is described along with its modeling, numeric simulation and some factory tests. The system, named Naval Package (NP), is part of a demonstrative programme commissioned by Italian Navy for preliminary evaluations of Medium-Voltage DC (MVDC) supply technologies aimed at equipping her future vessels. The NP is made by a dual-star alternator, whose two stator three-phase windings respectively feed two diode-rectifier full-bridges. The alternator (rated speed 6300 rpm) is designed to be moved by a 22000 rpm gas turbine through a gearbox. This paper will present NP innovative issues, with reference to design solutions, operative requirements, dynamic modeling under normal and faulty conditions and some factory tests.

Changes in presynaptic inhibition of Ia terminals directed to flexor carpi radialis (FCR) motoneurones (MNs) were investigated in normal human subjects at rest and during voluntary wrist flexion and extension. To that end, two independent methods were used: (1) the radial-induced D1 inhibition of the FCR H reflex, which assesses the excitability of PAD (primary afferent depolarisation) interneurones controlling presynaptic inhibition of Ia terminals mediating the afferent volley of the FCR H reflex; and (2) the heteronymous monosynaptic Ia facilitation induced in the FCR H reflex by intrinsic muscle Ia afferent stimulation, which assesses the ongoing presynaptic inhibition of Ia terminals. With respect to results at rest, it was found that at the onset of (and during tonic) voluntary wrist flexion, D1 inhibition was reduced and heteronymous monosynaptic Ia facilitation was increased. This suggests that, as in the lower limb, presynaptic inhibition is decreased on Ia terminals projecting to MNs involved in the voluntary contraction. In contrast with results observed in the lower limb, presynaptic inhibition of Ia terminals to FCR MNs was also found to be reduced at the onset of a voluntary contraction involving the antagonistic wrist extensors, suggesting that presynaptic inhibition of Ia terminals projecting to wrist flexors and extensors might be mediated through the same subsets of PAD interneurones. This is in keeping with other features showing that the organisation of reflex pathways between wrist flexors and extensors differs from that observed at other (elbow, ankle) joints.

Forty patients were admitted to a hospital emergency department after closed chest injury. Chest X-rays, a-p and lateral, with low and high voltage, were performed in a supine position. The aim of the study was to show the interest of lateral films in the diagnosis of post-traumatic pneumo- and hemothoraces. A special technique, using a double-drawer plate holder, gave a good quality radiograph in emergency conditions without danger for patients with severe trauma. In 30 of the patients, chest radiographs confirmed pleural gas or blood collection. In ten of these, the diagnosis could only be made after radiographic examination. In nine other cases, radiographs showed an absence of hemo- or pneumothorax. Lateral views were very important in confirming a hemothorax and appreciating its volume, as well as in showing up partial pneumothoraces which could not be seen on a-p views. The interest of performing a lateral film in all the cases of chest injury is pointed out.