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Grazing incidence x-ray reflectivity (GIXRR) technique is commonly used for structural investigation of layered structures. In case of complex x-ray waveguide structure it is difficult to obtain structural parameters using GIXRR technique owing to narrowly spaced Kiessig fringes. We used GIXRR and soft x-ray reflectivity (SXR) technique to study the x-ray waveguide structure composed of 4 layers Al/ZrC/Al/W on a Si substrate. Structural parameters of the stacks, density, thickness and roughness of the layers, are determined through fitting of SXR data. Advantages of SXR over GIXRR for such layered structure are shown.

The results of experimental investigation of parametric radiation generated by 5.7 MeV electrons in a multilayer structure consisting of 100 Cr/Sc bi-layers deposited on a Si[3]N[4] membrane are presented. The multilayer structure was specially created for generation of parametric radiation with photon energy in "water-window" spectral range. First test measurements of angular distributions of radiation have been done and discussed.

All-electrons SCF-LCAO-MO computations for methane, ethane, propane, n-butane, i-butane, ethylene, propene, 1-butene, trans-2-butene and acetylene are presented. The basic functions are contracted gaussian orbitals. Theoretical results are discussed and related to available experimental data. Les molecules de methane, ethane, propane, n-butane, i-butane, ethylene, propylene, 1-butene, trans-2-butene et d'acetylene sont etudiees par la methode de Roothaan, dans une base de fonctions de Gauss contractees, en tenant compte de tous les electrons. Les resultats theoriques sont discutes en relation avec les proprietes connues de ces composes.

On deduit la forme explicite des integrales electroniques dans les systemes periodiques tridimensionnels. Dans la derniere partie, on decrit un procede general pour obtenir une expression analytique simple des bandes d'energie dans les cristaux. Explicit formulae are given for the computation of π-electronic integrals in three-dimensional periodic systems. A general procedure for obtaining analytical forms of the band structure is given at the end of this paper. In den dreidimensionnalen, periodischen Systemen leiten wir eine deutliche Form der elektronischen Integralen ab. Im letzten Teil dieser Arbeit beschreiben wir ein allgemeines Verfahren zur analytischen Darstellung der Energie banden in Kristallen.

On deduit une formulation matricielle generale de la methode des orbitales cristallines autocoherentes (LCAO-SCF-CO). L'organisation du programme de calcul correspondant (POLYCOD) est decrite dans la derniere partie de ce travail. A general SCF-LCAO theory for computation of the electronic structure in conjugated polymeric species is described. A computer program, POLYCOD, has been programmed and a short description is included at the end of this paper. Es leitet sich eine allgemeine Matrixgleichung aus der Kristalorbitalenmethode ab (LCAO-SCF-CO). Im letzten Teil dieser Arbeit beschreiben wir den hiermit verbundenen Rechenprogramm (POLYCOD).

The independence of the core terms on the dimensions of the periodic system is proved in a basis of orthonormalized orbitals, and it is shown that the infinite system can be caracterized by these integrals. The formalism for the orthogonalization of the orbitals and for the calculation of the different integrals in the new basis is described.

La reconnaissance du corps dans le miroir constitue une etape importante dans l'elaboration des representations du corps. Si l'existence de comportements anormaux dans les espaces speculaires est classiquement decrite chez patients les cerebroleses, les caracteristiques de ces conduites peuvent etre dissociees de celles rencontrees en cas de non-reconnaissance des objets ou lors d'un defaut de traitement des informations visuelles et constituer des syndromes distincts. L'utilisation therapeutique des informations speculaires a ete proposee initialement dans le traitement des douleurs fantomes de l'ampute. Le traitement par le feed-back visuel du miroir a ete utilise avec le meme succes dans un contexte de douleur chronique. Plusieurs etudes recentes, controlees suggerent que la therapie du miroir (TM) chez le patient hemiplegique ameliore la recuperation motrice, l'utilisation de l'espace et les fonctions de l'hemicorps paralyse. Les indications de la TM sont discutees a la lumiere de ces travaux et des mecanismes supposes sur le role des informations speculaires. Le recours a un miroir pourrait en effet, par l'image inversee renvoyee, forcer l'activation d'un membre deficitaire ou creer l'illusion de mouvement et, par consequent, l'evolution eventuellement constatee viendrait souligner le role de l'activite comme agent mediateur de la plasticite du systeme nerveux central.

Granulocytic sarcoma (GS) is a rare extramedullary tumor frequently associated with acute myeloblastic leukemia (AML). We report 3 cases of pediatric granulocytic sarcomas with various locations: skin, orbit, and bowel. Cases 1 and 2 were associated with AML; case 3 was isolated. In all 3 cases, the diagnosis was delayed or initially missed. Pathology and immunohistochemistry data identified the disease. GS is treated with chemotherapy, like AML. The prognosis of GS seems better than that of isolated AML.

The application of a model potential technique for calculating band structures of polymers is described. In this approach, the valence Hamiltonian is a sum of a kinetic term and of various effective atomic potentials chosen in a nonlocal form of Gaussian projectors. Actual results on polyethylene and polyacetylene (infinite polyene) are given.

Objectives Retrospective analysis of the efficiency of a protocol for care of chronic vegetative states (CVS) and minimally conscious state (MCS) in Lorraine. Material and method Two indicators are used: protocol activity (number of patients hospitalized between 1988 and 2006, number of admissions per year, of requests per year, origin of requests, waiting time) and the epidemiological data (age, sex ratio, etiology, length of stay, geographic origin, number of deaths, number of hospital discharges). The number of CVS and MCS and patients having progressed towards arousal is specified as well as the technical procedures (orthopedic surgery, number of tracheotomies). Results Forty-seven patients (30 males and 17 females) were hospitalized in a 12-bed unit. The number of admissions per year was 2.4, and the annual number of requests varied between five and 15. Hospitalization times ranged from six to 18 months. The average length of hospitalization was 41 months. Eighty-eight percent of the cases were residents of Lorraine. The etiology was traumatic (53%), vascular (38% including 12% anoxia), miscellaneous (9%). Fifteen percent rate of return to arousal (average time period: 28.41 months, traumatic etiology) with hospital discharge in four cases. Conclusion The protocol is managed as part of a local scheme and enables an appropriate response to a specific clinical profile by providing up-to-date multidiscipline follow-up care and a rapid solution should intercurrent events occur (signs of arousal, orthopedic deterioration, change of environment). Typical limitations are geographical remoteness and difficulties with family support care.

Hip dynamics in the intact limb during the beginning of stance phase in unilateral trans-tibial amputees (TTA) was studied to evaluate its contribution to compensatory function. We hypothesized (1) an increase in hip total work during H1 power phase (0-30% of gait cycle) including an initial negative phase and (2) an intensification of the hip work in response to uncomfortable gait induced by prosthesis misalignment. Three-dimensional gait analysis was conducted in 17 unilateral TTA and 15 healthy subjects walking at the same self-selected speed in three prosthetic alignments: initial alignment (IA); IA altered either by 6 degrees of internal rotation (IR) or by 6 degrees of external rotation. Patients reported best comfort of gait in IA condition and discomfort mainly in IR condition. During the H1 power phase, in intact limbs a consistent initial flexion movement of the hip (0-8% gait cycle) was associated to negative work and was followed by hip extension and positive work whereas in both prosthetic and control limbs only hip extension and positive work occurred (except in one healthy individual). Absolute value of hip work during H1 phase was significantly higher in intact and prosthetic limbs compared to control limbs in IA condition and was further significantly increased in IR condition only in intact limbs demonstrating a compensatory function of the latter. In intact limbs, early hip negative work contributed to energy absorption in addition to the knee joint probably to compensate the lower energy absorption exerted by the prosthetic limbs.

Resume L’exposition, la noyade sacree et la reparation sont trois rituels du culte Vodoun, encore pratiques au Benin. L’exposition essentiellement consacree aux enfants malformes est un rituel passif. Elle permet a la societe traditionnelle beninoise de rester en regle vis-a-vis des ancetres et des divinites en abandonnant ces enfants dans la foret sacree et simultanement de gommer les stigmates d’angoisse. Ce type d’infanticide a but eugenique presente des similitudes avec l’exposition pratiquee dans la civilisation greco-romaine antique. La noyade sacree est realisee dans une ambiance de festivite dediee au culte Tohossou (divinite des eaux) durant laquelle l’enfant malforme est noye ; celui-ci devient alors une divinite a venerer. Fort de son ascendance, il veille desormais sur la famille et la collectivite. Le chagrin des geniteurs est ainsi sublime. La reparation est reservee aux « enfants sorciers » nes anormalement soit par une presentation dystocique (podalique ou occipitosacree) soit « en tuant leurs genitrices » en per- ou post-partum ou en debutant la dentition par la mâchoire superieure. Ces comportements violents et/ou s’ecartant de la norme condamnent ces enfants a une mort brutale apportant la quietude dans ces tribus. Ainsi, l’exposition et la noyade sacree en eliminant systematiquement les malformes, seraient un facteur sensible de reduction du nombre des deficients congenitaux dans l’ere culturelle beninoise. Certains enfants sorciers, sauvegardes par les organisations non gouvernementales (ONG), preserves d’exposition ou de reparation echappent a la mort ; ils ne peuvent plus par la suite continuer a vivre dans leurs tribus d’origine. Quelques hypotheses tentent d’interpreter ces rites.

Resume Objectif Le but de cette revue generale est de faire le bilan de connaissances actuelles sur l’evolution anatomique, histologique et physiologique des muscles chez les patients amputes tibiaux. Materiel et methode Revue de la litterature de PubMed et Reedoc, concernant les publications ayant trait au moignon des amputes tibiaux, son evolution, son volume, ses modifications histologiques et aussi les modifications de l’equilibre et de la marche apres une amputation. Resultats Les muscles des patients amputes presentent, du cote lese et du cote sain, une amyotrophie avec une reduction du diametre et du nombre de fibres et, en particulier, les fibres lentes (fibres de type I). Cette amyotrophie, heterogene dans son importance et dans sa repartition, atteint 25 % sur le quadriceps ou elle predomine sur le compartiment interne alors qu’elle est non significative sur les ischiojambiers. Elle trouve ses origines, d’une part, dans des modifications anatomiques secondaires au geste chirurgical. La perte de l’insertion distale d’un muscle ou sa reimplantation non anatomique favorise son amyotrophie. Et, d’autre part, dans des modifications du schema d’activation des muscles. Les ischiojambiers assurent la propulsion en l’absence du triceps sural et les muscles residuels du moignon presentent des contractions necessaires au maintien de l’emboiture. Le patient ampute presente un nouvel etat musculaire, retentissant sur la marche qui devient asymetrique et plus exigeante en energie, la sensibilite proprioceptive modifiee necessite une periode d’apprentissage pour retrouver un controle postural optimal.

Nocardiosis is a rare infectious disease in children. We report here a disseminated nocardiosis in a child with acute lymphoblastic leukemia. The patient presented prolonged febrile neutropenia and nodular pneumopathy. Based on the amplification of a 16S rDNA, a PCR assay detected Nocardia sp. in the patient's bronchoalveolar lavage (BAL) fluid. Culture of BAL samples yielded Nocardia nova colonies after 2 weeks of incubation. Hepatic, splenic, renal and cerebral localisations were detected on extension checkup. trimethoprime-sulfamethoxazole and amikacine were started given the results of PCR assay, with a good response. Improvement of the patient's general condition led to complete chemotherapy under ciprofloxacine and ceftriaxone treatment, without nocardiosis reactivation. Nocardiosis is a rare complication in children with acute lymphoblastic leukemia. trimethoprime-sulfamethoxazole prophylaxis is widely used to prevent Pneumocystis jiroveci infection in children with haematologic malignancies. As Nocardia species are usually sensible, trimethoprime-sulfamethoxazole could play a role in Nocardia prophylaxis in such population. In our patient, compliance with trimethoprime-sulfamethoxazole had been low. Nocardia species are relatively fastidious growth bacteria and are difficult to isolate with classical bacteriological techniques. Molecular methods are now available, with a good sensitivity and fast results allowing to start an appropriate antibiotherapy before culture results, as early treatment is a major prognosis factor in nocardiosis. Nocardia infection should be suspected in case of nodular pneumopathy in immunocompromised children. An extension checkup should be performed to detect secondary localisations.

Objective: To search for specular disorders of body representations in right hemisphere stroke. Background: Mirror self-misidentification, asomatognosia, and personal confabulation are similar to body illusions or changes in sensorial or sensorimotor perceptions generated by mirror in right brain damage patients with body image disorders. Method: Prospective study. Ten consecutive right-handed patients (1) performed body part naming and localization tasks and (2) were examined for asomatognosia at the acute phase of stroke, then at least 3 months after stroke, under 3 test conditions: without a mirror, with a conventional mirror, and with an inverted mirror. Video recordings of the tests were analyzed to assess performance. Results: Analysis of variance of the data confirmed that the interaction of mirror's conditions (specifically without a mirror vs. an inverted mirror) with subtest type was significant. The errors are symmetrically distributed. Asomatognosia was "reactivated" in 10 patients who experienced asomatognosia during the acute phase. No particular pattern characterized the clinical manifestations of asomatognosia. Conclusions: A causal conflict of sensorial input is proposed. The specific symptoms observed would suggest the existence of an incomplete specular Gerstmann syndrome and/or Anton Babinski syndrome. These results emphasize the role of specular input in the generation of body representations and self-awareness.

We present the non-destructive analysis of aperiodic Mo/Si multilayers by X-ray emission spectroscopy induced by electrons. The Si 3p occupied valence states of the silicon atoms present within these structures are analysed. Because of the great sensitivity of these states to the physico-chemical environment of the Si atoms, it is possible to distinguish the emission from the center of the Si layer (amorphous silicon) to that of the interfacial zones between the Mo and Si layers. Thus, the presence of molybdenum silicides is evidenced in the interfacial zones. It is also shown that the relative proportion of interfacial silicides depends on the deposition conditions.

Etched and coated multilayer gratings and simple multilayers are investigated by means of x-ray scattering (XRS) and grazing x-ray reflectivity (XRR). Two types of gratings are studied: one lamellar grating coated by a La/B4C stack and two lamellar gratings etched in a Mo/B4C multilayer structure with different cyclic ratios. XRS measurements are presented as reciprocal space mappings or Q-mapping and the origin of the different structures observed in the Q-mapping are discussed in terms of typical coherent and diffuse scattering processes (Bragg spots, grating-Bragg spots, Bragg sheets, grating diffuse sheets, Yoneda wings, etc). From the XRS and XRR measurements, some structural parameters of the mirrors and gratings such as periods and roughness characteristics are estimated.

Resume Objectifs Exposer la place de l'exploration situationnelle de l'activite locomotrice et l'interet des methodes d'analyse ambulatoire. Decrire les capteurs, les variables mesurees, les systemes de monitorage a disposition. Materiel et methode Revue de la litterature et experience personnelle. Pour chaque methode et technique d'exploration ambulatoire, les principes, les objectifs et les limites sont decrits. Resultats Les monitorages d'activites d'origine accelerometriques tendent a s'imposer compte tenu de la richesse des informations contenues dans la variable « acceleration », de leur fiabilite et des applications aujourd'hui developpees. Leur pertinence clinique est accrue lorsque les resultats sont associes a un monitorage d'effort (frequence cardiaque). Les podometres et actimetres, d'utilisation plus simple, peuvent apporter des reponses quantifiees et resultantes de l'activite locomotrice. Leur choix et leur modalite d'utilisation doivent etre adaptes au probleme prealablement defini avec precision. Conclusion Les monitorages d'activite et de longue duree constituent un progres considerable en parfaite coherence avec la medecine physique et de readaptation : mesurant la performance ils sont les temoins de l'activite et de la participation. La connaissance simultanee des conditions environnementales de l'activite en ameliorerait l'interpretation.

Artificially fabricated multilayers that exploit the effect of Bragg diffraction at long wavelengths are used as X-ray optical components. Periodic ultrathin bilayer stacks of, alternatingly, a metallic reflection layer and a non-metallic spacer layer prepared as @mm-scaled surface grating promise particularly high performance in applications as X-ray filters for high-resolution spectroscopy. Such gratings can be prepared by multilayer deposition onto Si(001) gratings or by coating flat Si(011) substrate surfaces with a multilayer, followed by subsequent etching of a grating structure. The structural quality of ultrathin multilayer gratings of both types has been characterized quantitatively combining TEM bright-field imaging of specimen cross-sections and applying a geometric phase method. The geometric phase method has been originally developed for the analysis of local displacement fields from HREM images and allows to obtain the relevant structure parameters. The application of this method to the characterization of Mo/B"4C and La/B"4C multilayer systems shows that the functionally decisive structure parameters, such as layer perfection, layer periodicity, and layer orientation, can be obtained with high precision from evaluation of TEM bright-field images. The essential role of such data analyses for a quantitative characterization of multilayer systems and for optimising the layer deposition techniques in the fabrication of X-ray optical layer systems will be demonstrated and discussed.

Multilayer interference mirrors (MIMs) are widely used as low-resolution monochromators for soft x-ray wavelength dispersive spectrometry (WDS). It is now possible to fabricate multilayer monochromators with medium resolution by etching MIMs with a large number of bilayers according to the profile of a lamellar grating. It will be shown both theoretically and experimentally that these multilayer gratings with appropriate characteristics can be used as monochromators for soft x-rays, whose spectral resolving power is considerably improved with respect to mere interference mirrors. Moreover, tunable soft x-ray sources based on the interaction of medium-energy electron beams with periodic multilayer structures are presently being developed in several countries. The physical processes involved in this type of sources belong to the class of quasi-Cerenkov emission. Among them are resonant transition radiation and parametric radiation. We present the basic concepts and the first experimental results concerning this new type of sources which should be very interesting for WDS.

Le ortesi della mano, sia nella concezione che nella realizzazione, devono rispondere a degli obiettivi terapeutici precisi: stabilizzare un’articolazione dolente o instabile, correggere un difetto di ampiezza o una deformazione, supplire a un deficit motorio, favorire una riparazione dei tessuti cutanei o sottocutanei. Ad ogni azione meccanica in una data situazione corrisponde una scelta preferenziale di moduli di base, di materiali. di aggiunte, soprattutto di motori. Questa ortesi puo essere definitiva, in quanto assicura un compenso, ma e per lo piu temporanea. In questo caso deve poter essere modificata durante il recupero e coordinata in particolar modo con i protocolli di rieducazione. Dopo una descrizione precisa e illustrata della concezione e della realizzazione delle ortesi, vengono descritte le indicazioni principali nel campo della reumatologia, della neurologia e delle ustioni; vengono esposte le ortesi della mano nei bambini (specificita, particolarita tecniche, indicazioni principali) Questo strumento terapeutico e oggetto di un consensus professionale e impone pertanto una prescrizione medica precisa. una realizzazione rigorosa, una sorveglianza attenta e una valutazione degli effetti.

Las ortesis de la mano, tanto en lo que se refiere a su concepcion como a su realizacion, deben responder a objetivos terapeuticos precisos: estabilizar una articulacion dolorosa o inestable, corregir un deficit de amplitud o una deformacion, suplir un deficit motor y favorecer la reparacion de la piel y del tejido subcutaneo. Para cada accion mecanica en una situacion determinada se escogen modulos de base, materiales y accesorios especificos, en especial motores. El aparato ortopedico puede ser definitivo con el fin de proporcionar una compensacion, pero la mayoria de las veces es temporal. En este caso, se modifica a medida que avanza la recuperacion, por lo que debe estar bien coordinado con los protocolos de rehabilitacion. Despues de proporcionar una descripcion detallada e imagenes del fundamento y de la realizacion de las ortesis, se mencionan las indicaciones principales en reumatologia, neurologia periferica, traumatologia y quemados; tambien se comentan las ortesis de la mano en la infancia (especificaciones, caracteristicas tecnicas, indicaciones principales). Este dispositivo terapeutico, que es motivo de consenso profesional, impone una prescripcion medica precisa, una realizacion minuciosa, un control regular y una valoracion de sus efectos.

This prospective study examined the effects of prismatic adaptation on visual exploration strategies in patients with left unilateral spatial neglect (USN). Photo-oculo-graphic gaze recordings were obtained, as the subjects (28 brain-damaged; 15 control) performed a free visual exploration task before and after a session of prismatic adaptation. (i) Before prismatic adaptation, the pattern of visual exploration described two subgroups of patients (symmetrical exploration of hemispaces - similar to the control subjects, deficient exploration of left hemispace). Twelve of 20 patients failed to describe significant elements in the left part of the displayed image. Several visuoverbal patterns were observed, some dissociating visual exploration and verbal description. (ii) Immediately after prismatic adaptation, patients with asymmetrical visual exploration presented a significant increase in the number of point fixations and saccades in the left hemispace. Patients with symmetrical exploration presented the opposite pattern. Improved pattern of visual exploration contrasted with an absence of improved verbal description. Eye movements and visuoverbal descriptions exhibit heterogeneous and dissociated patterns before and after prismatic adaptation. This results demonstrate that prismatic adaptation has no effect in certain patients, suggesting that therapeutic indications and evaluation of prismatic test results should take into consideration the heterogeneous nature of USN.

Degenerative osteoarthritis in subtalar and midtarsal joints occurring after tibiotalar arthrodesis may be related to biomechanical factors. For patients with tibiotalar arthrodesis walking with their everyday shoes, the ground reaction force is posterior at heel-off and the maximal foot-tibia dorsiflexion is at its upper limit. We hypothesized that increasing the instep of the shoes would improve these abnormalities. Three-dimensional gait analysis was done in nine patients with ankle arthrodesis fused in the neutral position and for 10 control subjects. Four conditions of walking were tested: barefoot, wearing everyday shoes, wearing everyday shoes with the instep increased by 1 cm, and wearing everyday shoes with the instep increased by 2 cm. In the arthrodesis group, the two modified delayed heel-off shoe conditions shifted the ground reaction force closer to the metatarsal heads at heel-off to a normal range, and reduced the maximal foot and tibia dorsiflexion angle. Based on these results, patients with a tibiotalar arthrodesis in the neutral sagittal position may be advised to choose shoes with an instep of approximately 25 mm.

We investigate on a Mo/Si multilayer interferential mirror (MIM) as a function of annealing at temperatures up to 600 °C. The physicochemical state of the silicon atoms within the MIM is characterized by X-ray emission spectroscopy (XES). A thin silicide layer is detected at the interfaces of the as-prepared system, whose thickness increases upon annealing. Measurements of the reflecting power at 1.33 nm show that both the reflectivity and the period markedly decrease as the annealing temperature increases, thus stressing on the interplay between the interface physico-chemical state and the optical properties. Our results shed light on the highest temperature regime, 600 °C, where the MIM loses its periodic structure as the majority of the silicon atoms are involved in the MoSi 2 compound. The diffusion coefficient is estimated from the evolution of the reflected intensity and the period. An activation energy of the diffusion process of 0.52 eV is deduced.

Publié dans The European Physical Journal - Applied Physics 31, 147 (2005); International audience; A new laboratory apparatus devoted to the characterization of various devices for the X-UV range (100-5000 eV), such as mirrors, diffraction gratings, spectrometers or detectors is described. The apparatus includes open x-ray tubes as x-ray sources, a two-crystal monochromator for wavelength selection and a goniometer. Various examples of its use are presented : dispersive mode where the radiation coming from the x-ray tube is dispersed by the two-crystal monochromator, spectrometric mode where the goniometer is used as a plane x-ray spectrometer and reflectometric mode where a selected wavelength is used to perform absolute reflectivity measurements.

Introduction. – Review of the literature about evaluation of amputees. Materials and methods. – A search of the Medline and Reedoc databases with the key words lower limb amputee, upper limb amputee, evaluation of lower limb amputee, evaluation of upper limb amputee, survey of lower limb amputee, survey of upper limb and the same words in French for reports on the evaluation of amputees. Results. – Evaluations of amputees differ according to the level of amputation (lower or upper limb) and age (adult or child). They concern standing balance, walking (lower limb) and the mono- or bimanual prehensile capacities with or without prostheses in daily living activities and leisure (upper limb) as well as quality of life, personal satisfaction, psychological impact and, in particular, coping strategies. Discussion. – For lower-limb amputees, tools to evaluate include scales of deambulation, of which few are valid in French, and global scales (on locomotor capacities, quality of life and satisfaction), which have been recently validated, but only one of them is valid in French. For upper-limb amputees, specific and valid tools are not available for adults; however, for children some functional capacity scales in daily activities have been validated and take into account psychomotor development. None of these tools are valid in French, and their use is scattered and limited to validation studies. Conclusion. – Only a few tools to evaluate amputees are valid in French for adults, and they concern lower-limb amputees only. Validating some of these tools in French is necessary.

Un spectrogoniometre de laboratoire utilisant comme source un tube emettant des radiations caracteristiques dans le domaine X mou et X-UV a ete developpe au Laboratoire de Chimie Physique (CNRS/UPMC) dans le cadre de l'Action Coordonnee Optique du CNRS. L'appareil comprend un monochromateur de type double-cristaux equipe de miroirs multicouches ou de cristaux de grande periode et un goniometre θ-2θ. Il permet des mesures de pouvoir reflecteur et de diffusion de dispositifs optiques, en particulier de miroirs et reseaux multicouches. Dans un futur proche il sera aussi destine a la caracterisation de nouvelles sources et de detecteurs X-UV. L'appareil peut aussi etre utilise comme spectrometre a cristal plan si l'anode est remplacee par l'echantillon a analyser. Differents exemples des possibilites offertes par cet instrument operant en mode reflectometrie ou en mode spectrometrie sont presentes.

Paysant J, Andre J-M, Martinet N, Beis J-M, Datie A-M, Henry S, Dap F. Transcranial magnetic stimulation for diagnosis of residual limb neuromas. Arch Phys Med Rehabil 2004;85:737–42. Objective To analyze the mechanism and examine the potential diagnostic contribution of transcranial magnetic stimulation (TMS) in diagnosing painful, clonic, and/or autonomic manifestations in amputees' residual limbs. Design Prospective study. Setting Regional rehabilitation institute at a medical school in France. Participants Thirty-four amputees (24 with myoclonus, stump pain, or trophic skin disorders; 10 controls with no stump symptoms). Interventions Not applicable. Main Outcomes Measures TMS performed before and after correcting prosthesis adaptation. Results TMS induced pain in 12 amputees, clonic manifestations in 4, and autonomic manifestations in 2. Twelve patients underwent magnetic resonance imaging that showed neuromas in all 12. After neuroma resection in 9 amputees, TMS no longer provoked abnormal manifestations. TMS did provoke abnormal manifestations after resection in 3 patients who had postoperative recurrent neuromas. The response to TMS was negative in subjects with a clinically silent neuroma (n=7). The response was also negative in all patients with other stump anomalies whose clinical manifestations fully regressed after conservative treatment. There was a highly significant correlation between the presence of a pathologic neuroma and TMS-induced abnormal manifestations ( P Conclusions TMS can provoke symptoms in patients who experience spontaneous or evoked symptoms related to a neuroma. Induced symptoms are proportional to spontaneous symptoms. Removing the neuroma can stop stump symptoms and reverse the TMS effect. The response to TMS was negative in the control subjects with clinically silent neuromas; conservative treatment was successful in these cases. TMS-induced abnormal manifestations underlying mechanisms are discussed (ephaptic transmission in neuromas).

Resume Introduction. – Les resultats fonctionnels des reimplantations apres amputation traumatique de main sont consideres comme bons en depit des frequents troubles de mobilite des doigts longs et des troubles de la sensibilite quasi constants. Objectifs. – Evaluer la recuperation et les compensations mises en œuvre a l’origine des performances de la prehension. Materiel et methodes. – Etude prospective de huit sujets masculins droitiers amputes distaux du membre superieur gauche reimplante depuis plus de deux ans. Groupe temoin de huit sujets apparies selon l’âge, le sexe, la lateralite. Evaluation des recuperations sensitive (monofilaments), motrice (TAM) et fonctionnelle (Box and Blocks test et 400 points) et de la reinsertion socioprofessionnelle. Evaluation cinematique par systeme opto-electronique et cube dynamometrique : sequences temporelles de la prehension lors d’une tâche de saisie–transport, deplacements du tronc et des membres (bras, avant-bras, main). Etudes des correlations entre les resultats fournis par les epreuves cliniques et fonctionnelles et les donnees cinematiques. Resultats. – La replantation se caracterise par une recuperation remarquable de la duree absolue et relative des differentes phases decrites lors de la prehension physiologique. Seule la phase de saisie est significativement allongee chez les reimplantes en rapport avec les difficultes motrices et sensitives residuelles comme en temoignent les correlations avec les tests cliniques. La dependance au controle visuel est accrue, probablement en raison des troubles sensitifs superficiels et profonds. Les compensations portent sur une deviation globale de l’ensemble du membre superieur reimplante, semblant a rapporter principalement a une deviation du tronc dans le plan lateral. Conclusion. – Le patient ampute et reimplante de main developpe une strategie de deplacement homogene du tronc et de la ceinture scapulaire de facon a compenser le raccourcissement et la reduction de la mobilite active de la main. Cette amplification d’une strategie observee chez le sujet sain aboutit a une compensation efficace, respectant les caracteristiques des phases de la prehension normale.

Nous presentons les modulations d'intensite de la raie Si Kα emise par une structure multicouche en fonction de l'angle de sortie des photons. L'observation est realisee autour de la direction correspondant a la direction de Bragg de la raie Si Ka par la multicouche. L'echantillon est irradiee par un faisceau d'electrons dont l'energie est comprise entre 2 et 6 keV. Une importante variation d'intensite est observee dans le domaine angulaire correspondant a la figure de diffraction de la structure emissive. Une augmentation voisine de 15% de l'intensite de la raie est mesuree dans la direction de Bragg de la multicouche quelle que soit l'energie des electrons incidents. La modulation est interpretee sur la base du theoreme de reciprocite. A la suite de la proposition de Yariv and Yeh [J. Opt. Soc. Am 67 (1977) 438], nous envisageons une application des structures multicouches comme resonateur pour parvenir a un laser X a retroaction distribuee.

Foisneau-Lottin A, Martinet N, Henrot P, Paysant J, Blum A, Andre J-M. Bursitis, adventitious bursa, localized soft-tissue inflammation, and bone marrow edema in tibial stumps: the contribution of magnetic resonance imaging to the diagnosis and management of mechanical stress complications. Arch Phys Med Rehabil 2003;84:770-7 Objective: To assess the contribution of magnetic resonance imaging (MRI) in the diagnosis of tibial stump bursitis, in the establishment of differential diagnosis, and in the therapeutic management prosthetic-stump interface, mainly by adaptation of the prosthetic device. Design: Two-year, prospective, consecutive series. Setting: University-affiliated prosthetic and rehabilitation center and university department of radiology. Participants: A group of 17 persons with stump problems identified from a total of 139 consecutive below-knee amputees with prosthesis problems. Interventions: Not applicable. Main Outcome Measures: Clinical symptoms and MRI. Results: Clinical symptoms (variable stump volume, fluctuating mass at palpation with or without mechanical pain) were suggestive of bursitis in 10 patients. MRI confirmed bursitis in 9 and identified 1 in whom clinical signs suggested neuroma, giving an incidence of 10 of 139 amputees (7.2%). MRI identified 13 sites of bursitis (adventitious bursa, 11; synovial bursitis, 2) and 5 localized areas of soft tissue inflammation. MRI showed diffuse muscular edema at 1 site of clinically suspected bursitis, and bursitis at another site of suspected neuroma. Calcified bursitis was observed in 1 case. Bone abnormalities associated with bursitis (n=7) included osteophytes or fracture (n=4) or bone marrow edema (n=3). Two asymptomatic neuromas were also identified. MRI-guided modifications of the prosthetic interface led to favorable outcome in all cases. Conclusion: Bursitis, adventitious bursae, and areas of localized soft-tissue inflammation are different aspects of the same disorder resulting from a mechanical conflict between the stump and the prosthesis socket. Besides contributing to diagnosis, MRI provides a precise assessment necessary for correcting the prosthesis-stump interface in a way that reduces mechanical stress and subsequently cures bursitis.

Nous presentons les principes et les performances attendues de nouvelles sources de rayonnement X et X-UV basees sur la generation de rayonnement de type Tcherenkov a partir de l'interaction de faisceau d'electrons relativistes avec des structures multicouches periodiques.

Objectives: To study different typolologies from visuo-verbal behavior concerning the arrest and the treatment of visual information in patients with spatial hemineglect. Methods: Ocular movements were monitored by photo-oculography in thirty controls and twenty-three patients with neglect. During a letter reading task, the movements, number of entries into predetermined zones of the visual field, time spent in each zone, and the verbal responses were recorded. Four profiles may be anticipated for such trials: normal scanning and reading (S+R+), normal scanning without reading (S+R�), absence of both scanning and reading (SR�), abnormal scanning with reading (SR+). Results: The letter projected in each of the 4 quadrants was scanned and correctly identified by all of the controls with no differences in scanning times. Among patients, the 4 possible behavior patterns were found along with differences in exploration duration per zone ( p< 0.05) and number of times specific zones were attained ( p< 0.05). Conclusions: Our results confirmed the heterogeneity of the mechanisms of neglect and suggest that rehabilitation procedures adapted to each profile might be useful.

Resume OBJECTIF : Evaluer les benefices apportes par une chirurgie precoce des escarres pelviennes par rapport a la cicatrisation dirigee dans une population de sujets medullo-leses. MATERIEL ET METHODE : La population etudiee est constituee de 53 patients (62 escarres) repartis en deux groupes : le groupe 1 comprend 30 patients (34 escarres) presentant des escarres pelviennes de stade III ou IV (NPUAP) traitees en premiere intention chirurgicalement, inclus consecutivement pendant une periode de 2 ans ; le groupe 2 comprend 23 patients (28 escarres) inclus de facon retrospective presentant des escarres pelviennes de stade III ou IV traitees en premiere intention par cicatrisation dirigee par la meme equipe de soins. Les criteres de jugement retenus sont le delai de cicatrisation et le delai de reprise de la station assise au fauteuil. L’analyse statistique fait appel au calcul de l’ecart reduit. RESULTATS : Dans le groupe 1 le delai moyen de cicatrisation quelle que soit la localisation de l’escarre est de 42 jours et le delai moyen de remise au fauteuil de 39 jours. Dans le groupe 2 la cicatrisation ne peut etre obtenue medicalement que dans 13 cas et dans un delai moyen de 180 jours. Les differences sont statistiquement significatives (p DISCUSSION - CONCLUSION : L’originalite de cette etude resulte dans la comparaison de deux traitements au sein de deux groupes de patients ayant des caracteristiques demographiques proches. Elle demontre clairement l’interet de la chirurgie precoce de l’escarre par rapport a la cicatrisation dirigee et illustre la necessite de filieres medico-reeducatives specialisees.

Resume Introduction : Les perceptions par les amputes de leur corps ont fait l’objet de multiples descriptions souvent desordonnees. L'objectif est d'etablir une classification synthetique. Methode : Revue a partir d'etudes prospectives de 75 amputes recrutes de facon consecutive. Analyse a partir de declarations libres puis semi-directives. Resultats : Selon la perception ou non du membre ampute, selon l’acuite, la forme, la posture, le mouvement, le caractere reminiscent du membre ampute percu, il est possible de distinguer des membres fantomes normaux, deformes ou commemoratifs (de rappel), des illusions de normalite corporelle, des perceptions de l’etat reel. Discussion : Quel que soit le modele (neuromatrice) sur lequel repose la construction de l’image corporelle, les representations correspondant aux perceptions identifiees utilisent differents referentiels (innes, identitaires, autobiographiques) ainsi que les informations instantanees, d’origine peripherique, traitees par des structures cerebrales reorganisees. A chaque type de perception correspond une modalite de representation particuliere. Conclusion : Cette approche, compatible avec les donnees de la litterature, permet de mieux comprendre les differences entre ameliques et amputes tardifs ainsi que les comportements a l'egard de l’appareillage prothetique.

A justification of the Mulliken approximation is given. It is shown that this approximation gives correct results for π-type polycenter integrals. Corrective terms are also deduce d for σ-type polycenter integrals.

On propose un modele theorique qui rend compte des rayonnements de transition resonnant et parametrique emis par une multicouche periodique traversee par un electron dont la vitesse est constante. Des exemples numeriques donnant le rendement photonique et la distribution spatiale mettent en evidence l'interet de ces dispositifs comme sources de rayonnement X-UV.

Les effets d'un chauffage thermique continu sur les performances en terme de reflectivite de miroirs multicouches Mo/Si, Mo/C, Ni/C sont etudies. Les mesures de reflectivite autour de 100eV sont realisees en utilisant le rayonnement synchrotron de Super-ACO au LURE. Des variations de reflectivite en fonction de la temperature sont enregistrees. On observe que la periode du miroir Mo/Si decroit, celui du miroir Mo/C reste constante et celle du miroir Ni/C croit quand la temperature augmente. Ces comportements sont discutes dans le cadre de la science des materiaux.

Aim. To show asymmetric leg activity during walking in healthy subjects. Design. Two electrogoniometers were used to measure the amplitude of the flexion-extension movements of both knees during walking. Background. Walking is considered to be a symmetrical activity. Quantitative studies of walking often only consider one side of the body or remove differences between individuals by averaging results. Methods. The handedness, lateral eye dominance and footedness of 31 healthy subjects were determined. A strain gauge electrogoniometer was then fitted to the outside of each knee to analyze the flexion-extension movements. The results were recorded automatically. The subject walked a distance of 30 m three times, with different attention levels: free walking (with no other task assigned), walking with attention diverted (whilst performing a mental task), and focused walking (walking as straight as possible in a straight line). Results. 51.6% of the subjects tested displayed asymmetry of the total flexion-extension movement of more than 5° between the two knees during free walking. The side favored (preponderance) by this asymmetry was not related to the handedness or other lateral dominance. The different attention levels did not significantly affect the characteristics of motion of the sub-groups studied (symmetric, right-favoring and left-favoring). Conclusions. The origin of this asymmetry, which is independent of handedness or attention level, could be the spinal stepping generator for which there is evidence in both animals and humans. Walking should not be considered to be a strictly symmetrical phenomenon. Relevance The demonstration of asymmetric leg activity during walking may lead to a better understanding of the way in which walking controlled. The presence of such asymmetry is normal, and it should be borne in mind during explorations of walking in both healthy and pathologic individuals.

We realized a laterally-d graded multilayer interference mirror using a special configuration of a sputtering deposition system. Metrology of this device was done (we have found the variation of period versus the lateral position) on the SB3 beamline, a CEA calibration station located at the ‘Laboratoire pour l’Utilisation du Rayonnement Electromagnetique’ in Orsay. A wide set of applications was shown by studying transmission of X-ray radiation transmitted through copper metal foil, especially spectral analysis in the L absorption edge. This analysis was simply realized by translating the laterally-d graded multilayer interference mirror at a fixed glancing angle.

We propose a method to reduce the bandpass of soft x-ray multilayer Bragg reflectors. It consists in etching down to the substrate a multilayer mirror having a large number of bilayers in order to get a lamellar grating with a multilayer bar width representing only 10%–30% of the grating period. The grating is used at the zeroth diffraction order. Once designed, this monochromator was tested with the Lα,β spectra of iron and copper.

The influence of the number of bilayers on the optical performances of actual X-UV multilayer interferential mirrors (MIMs) has been studied in order to emphasize the experimental restrictions in the designing of “thick” mirrors used for the development of etched multilayer gratings. Several sets of samples (W/C, Mo/Si) with increasing number of bilayers have been manufactured in the very same conditions by means of a sputtering technique. X-ray diffraction characterization at Cu-Kαradiation (λ = 1.54018 A) exhibits technical constraints in the achievement of multilayer structures with large number of bilayers. We obtain a gradual loss of reflectivity for deposition times greater than 1h 30 min to 2h without significant drift of the MIM's geometrical parameters (period and division parameter). In the same time, absolute reflectivity measurements at Cu-Lαradiation (λ = 1.333 nm) emphasize satisfying optical and spectroscopic performances of W/C thick samples (150 bilayers).

This paper was published in Chinese Optics Letters and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://www.col.org.cn/abstract.aspx?id=COL201311S10601-04. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law.; International audience; We use complementary analysis techniques to determine the structure of nanometric periodic multilayers and particularly their interfaces. We focus on Co-based multilayer which can be used as efficient optical component in the extreme ultraviolet (EUV) range. The samples are characterized using reflectivity measurements in order to determine the thickness and roughness of the various layers, X-ray emission and nuclear magnetic resonance (NMR) spectroscopies to identify the chemical state of the atoms present within the stack and know if they interdiffuse. Results are validated through the use of destructive techniques such as transmission electron microscopy or secondary ion mass spectrometry.