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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.

The moisture content of the epidermis was measured by magnetic resonance imaging (MRI), using transverse relaxation time. The spatial resolution was 86 microns, allowing a quantitative, accurate and localized determination of variations in epidermal hydration. The wrists of 15 volunteers were studied before and after application of a hydration cream. Results showed an increase of 15% of epidermal T2 after application of the cream. Moisture content curves varied according to different degrees of skin dryness. This study demonstrates that MRI is a useful tool in evaluation of epidermal hydration.

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.

Reciprocal inhibition between ankle flexors and extensors has been the subject of numerous studies in Man. They have demonstrated that this reciprocal inhibition is in all likelihood caused by a disynaptic pathway at least partly fed by Ia afferents. It is thus generally agreed that this reciprocally organized inhibition between ankle flexors and extensors in Man is similar to the reciprocal Ia inhibition described in the cat. This conclusion has, however, been challenged, when Jankowska and McCrea described in the cat a non-reciprocal group I inhibition involving interneurones co-excited by Ia and Ib afferents and mediating inhibition to both antagonistic and non-antagonistic motoneurones. The only way to distinguish between reciprocal Ia inhibition and non-reciprocal group I inhibition is to test if the inhibition is blocked by recurrent inhibition, since only Ia interneurones are inhibited by recurrent inhibition. In the present study, reciprocal inhibition from soleus to tibialis anterior was thus investigated following activation of soleus-coupled Renshaw cells in normal human subjects. It was found that reciprocal inhibition induced in tibialis anterior motoneurones by the activation of soleus group I afferents is deeply depressed by activation of soleus-coupled Renshaw cells. This finding provides the missing data to identify disynaptic inhibition between antagonistic ankle muscles as a reciprocal Ia inhibition.

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.

The calibration of several ions (Cl−, Br−, F− and OH−) measured with an ion selective electrodes (ISE) array has been carried out in the presence of interferents using an experimental design and multivariate calibration methods. Partial least squares regression and principal component regression do not seem to improve the test set prediction compared to multivariate linear regression. In the case of very slight or no interference on the ISE, each ion can be determined using the corresponding ISE and univariate calibration methods, but the use of multivariate methods does not lead to worse results.

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.

This investigation was designed to study the effects of post-activation depression in different spinal pathways fed by group I afferents available to investigation in human subjects. It was precipitated by a recent investigation in the cat showing that-contrary to the general assumption-post-activation depression is not a widespread phenomenon in the spinal cord. In 24 healthy subjects comparison was made between the effects of low and high-test stimulus rates on the monosynaptic Ia excitation, known to be subject to post-activation depression, and on oligosynaptic pathways fed by group I afferents. Both the amplitude of monosynaptic H reflexes and the amount of heteronymous monosynaptic Ia facilitation were significantly smaller at high than at low-test stimulus rates (1-2 s compared with 6-8 s between two consecutive stimuli). So was the amount of reciprocal Ia inhibition of tibialis anterior motoneurones. In contrast, the amount of other non-monosynaptic group I effects directed to the same motor nuclei (peroneal-induced excitation of quadriceps motoneurones, disynaptic non-reciprocal group I inhibition of flexor carpi radialis motoneurones, and D1 inhibition of flexor carpi radialis and soleus H reflexes) were enhanced at high stimulus rates. Results in humans confirm that post-activation depression depends on the type of group I afferents, and/or on the target neurones. The functional significance of the discrepancy between post-activation depression in pure Ia pathways and in other group I pathways is discussed with regard to the fusimotor-driven servo-assistance from Ia afferent discharges.

Pulmonary hypertension (PHT) represents one of the severest complications and is life-threatening for patients suffering from systemic sclerosis (SSc). In France, the modalities for screening and treating PHT related to SSc are not well codified and no consensus has been reached. We conducted a survey among physicians inscribed on the list of the French Research Group on Sclerosis (GRFS - Groupe de Recherche Francais sur la Sclerodermie) to gather information on the status of the management of PHT related to SSc.In 2002, we sent a questionnaire to 160 physicians, members of the GRFS, to assess the epidemiology and clinical profile of SSc patients as well as the modalities of screening and management of PHT in these patients.Eighty-eight physicians in 71 centres replied to the questionnaire. Each centre followed-up a mean of 33 SSc patients, with a global distribution of 53% limited and 47% diffused SSc. These physicians saw a mean of 5 new cases of SSc per year. The patients had been referred by town practitioners (53%) or from the hospital (47%). The mean number of SSc patients with PHT was of 5.1 per physician (1.5 new SSc + PHT patients per year). Almost all the centres (65/67) who replied systematically screened for PHT in SSc patients using Doppler echocardiography a mean of every 1.3 years. For the management of the patients exhibiting PHT, the majority (41/63) of centres collaborated with a specialized unit. Around one third of the centres treated these patients with calcium channel inhibitors (82%) and/or prostacyclin (90%). All the patients were followed-up by Doppler echocardiography. The majority of the physicians (72%) were interested in a research protocol on the subject and each could have included 4 patients, i.e., a total of 160.Pulmonary hypertension, a severe complication of SSc is screened for by the physicians of the GRFS using echocardiography with a frequency similar to Who guidelines (1.3 versus once/year).

Mooren's ulcer (MU) is a chronic peripheral corneal ulceration featuring conjunctival immunoglobulin deposits. It is considered as the result of a limbic immune process with hyperactivation of T and B lymphocytes. The etiology remains unknown. The response to topical steroid therapy and surgical procedures usually poor and the visual outcome can be devastating.Clinical follow-up of 3 patients who had rebel MU to conventional therapy, and were treated with 1g monthly intravenous cyclophosphamide.First patient was a 24-years-old man who had MU in his left eye. The response to surgical procedure and intravenous steroid treatment was poor and corneal perforation occurred. The affected cornea healed after 9 months of Cy treatment. The second patient was a 50-years-old man who had MU in his left eye, which did not improved with lamellar keratoplasty and topical steroid therapy. Corneal healing was obtained after 20 months of Cy treatment. The third patient was a 70-years-old man who presented with a furrowed MU in his right eye which healed with conjunctival resection and 4 months of Cy perfusion. No adverse effects of Cy was noted as opposed to Cy given orally.We report the effectiveness of 1g monthly intravenous cyclophosphamide (Cy) treatment in rebel MU. We suggest that immunosuppressive therapy using IV monthly Cy may be proposed in severe rebel MU.

Q fever is a worldwide zoonosis but is not often a common cause of fever among travellers returning from the tropics. We report a case of acute Q fever, revealed by a pneumonia and acquired by a traveller in French Guyana. The chest radiography showed alveolar opacities and pleural effusion. Biological abnormalities were elevated liver enzyme levels and thrombocytopenia. The patient improved or the third day of antibiotic treatment. She mentioned that 3 other people she lived with during her trip had been diagnosed with Q fever. A common source outbreak was then suspected. They all stayed in the same farm in French Guyana. Animal exposure occurred there, in particular with a goat and a dog (both were parturient). The disease was probably transmitted by airborne dust to our patient, as no other vectors of transmission were found. Since the clinical presentation of Q fever is not specific, in order for the physician to diagnose it, he must have an awareness of the disease. Our case emphasised that looking for risk factors of Coxiella burnetii exposures is particularly important. Amongst them, the most important seems to be contact with farm animals. The clinician should thus try to trace such a possible contact when treating a case of traveler's Q fever.

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.

Univariate and multivariate Chemometric methods are compared for the determination of ion concentrations measured with a 6 Ion-Selective Electrode array. Principal component analysis is applied as an exploratory method to observe the extent to which interferences occur. Two univariate calibration methods are compared. It is shown that univariate inverse calibration per- forms at least as well as classical calibration. The use of the former is therefore recommended. The use of partial least squar es, principal component regression and multivariate regression is discussed and the possibilities of the method are described.

A renin-secreting tumour has been observed in a 32-year-old female with severe hypertension known for 17 years. The excision of the tumour lead to the complete normalisation of the blood pressure. Histological examination showed that the tumour was benign, contained secretion granules at different stages of maturation, and derived from the juxta-glomerular apparatus. After reviewing the 40 cases previously reported in the literature we discuss the clinical presentation of this type of tumour and the approach to their diagnosis.

Human skin sections were studied using synchrotron-powered infrared microscopy. The superior lateral resolution achieved with this technique (diffraction-limited spot sizes) allows the detailed analysis of the biocomposition of the skin layers. It is shown that highly organized lipids are present in the stratum corneum, as evidenced by a slight frequency difference in the symmetric stretch mode of the methylene groups. Biochemical images were generated showing the precise location of the lipids, proteins and collagen across the skin section. More enhanced images were generated using a statistical approach (fuzzy C-means clustering). Penetration of two external agents (cyanophenol and a cosmetic compound, ethylhexyl methoxycinnamate) was studied. The penetration pathway across the stratum corneum is favored at locations of lower lipid concentration. Both compounds penetrated into the epidermis, but neither of them induced a change in the protein secondary structure. It was shown that hair follicle is a favored penetration pathway for these agents.

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.

Resume En conclusion, cette enquete nous a demontre que le paludisme post-transfusionnel etait moins rare en France que nous ne l'admettions : 56 cas ont ainsi pu etre recenses durant la periode de 1960 a 1974 et ce chiffre n'est probablement qu'un reflet imparfait de la situation. Dans notre pays, plasmodium falciparum, espece responsable des accidents les plus graves, est la forme la plus souvent incriminee et sa frequence s'accroit au cours des annees — 76,1 % des infestations durant la periode de 1970 a 1974. Enfin, nous avons confirme qu'une prevention de ces accidents doit tenir pour suspect tout sujet ayant sejourne dans les territoires impaludes, ce qui rend necessaire de connaitre a tout moment la carte epidemiologique de cette parasitose. Cette prevention devra etre notablement renforcee afin qu'en raison des mouvements des populations, le paludisme post-transfusionnel ne devienne en France une maladie d'avenir.

Resume Nous avons recherche des paraproteinemies monoclonales sur un echantillon de 2.000 donneurs de sang pris au hasard au Centre de Transfusion de Brest. Nous avons trouve une frequence de cette anomalie de 0.7 %. Tous ces sujets ont ete suivis pendant au moins une annee et sur les 14 cas depistes, deux se sont averes etre symptomatiques de myelome ou de cryoglobulinemie non diagnostiques, deux peuvent etre suspectes comme etant des myelomes au stade infraclinique, et 10 sont, pour l'instant, consideres comme etant essentiels ou benins ou asymptomatiques. Nous retiendrons le pourcentage eleve de cette anomalie dans notre population et — confirmant des observations precedentes — l'augmentation de cette frequence vers l'extreme ouest.

The injection in rabbits of vaccinal antigens combined with immunity adjuvants (in particular calcium phosphate) causes a local lesion in which it is possible to recognize histologically, after a transitory afflux of polymorphonuclear leukocytes, a central area of adjuvant deposit, a middle area of histiocytes and monocytes, and a peripheral immunogenic area of lymphocytes and plasmocytes. These two cellular zones are rich in highly fluorescent cells in the presence of an antiglobulin serum with an embedding technique which respects to the upmost the structures and immunoreactivity of the cells. These histological features are not completely observed on the separate injection of antigen or adjuvant. They must be interpreted, after a fleeting non-specific reaction, while taking into account the still poorly understood method of action of the inorganic adjuvant and spread of the antigen in the organism.

The inoculation into guinea pigs of 10 mg of BCG, obtained either from the Pasteur Institute original strain, or from a mutant isoniazid resistant strain, B1 catalase positive, caused in 40.4% of cases, the onset of abscesses at the point of injection. The frequency and course of these abscesses appear quite different with the two strains, 92.8% with the classical strain, persisting in more than half of the cases after one year, and 23.5% with the INH-resistant strains which regressed within 6 months. Histologically, the structure of the recent abscesses, with a large histiocytic wall often rich in bacteria, and a very cellular necrotic content, appears different from that of old abscesses with a thin wall and a heterogeneous content, calcification with reaction to foreign bodies, and presence of granules due to the persistance of bacteria. The INH-resistant strain is thus in the guinea pig, less aggressive and more rapidly eliminated than the classical Pasteur strain. The course and morphology of abscesses in guinea pigs are very similar to certain old lesions of human tuberculosis and involve, in all strains, phenomena of cell immunity both general and local.

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.

This inquire demonstrated that transfusion malaria was not so rare as we thought. So 56 cases have been numbered between 1960 and 1974, and probably they do not reflect exactly the real situation. In our country, plasmodium falciparum, specifically responsible of the most serious accidents, is the form most frequently incriminated and its frequency increases among the years: 76,1% of the infects between 1970 and 1974. At last we have confirmed that a prevent of those accidents must consider as a subject any one having resided in an impaluded country, and that implies a constant knowledge of the epidemiologic map of this parisitism. This prevent will be increased so that the transfusion malaria will not get a illness disease in France.