Aligned carbon nanotube based ultrasonic microtransducers for durability monitoring in civil engineering.

Structural health monitoring of porous materials such as concrete is becoming a major component in our resource-limited economy, as it conditions durable exploitation of existing facilities. Durability in porous materials depends on nanoscale features which need to be monitored in situ with nanometric resolution. To address this problem, we put forward an approach based on the development of a new nanosensor, namely a capacitive micrometric ultrasonic transducer whose vibrating membrane is made of aligned single-walled carbon nanotubes (SWNT). Such sensors are meant to be embedded in large numbers within a porous material in order to provide information on its durability by monitoring in situ neighboring individual micropores. In the present paper, we report on the feasibility of the key building block of the proposed sensor: we have fabricated well-aligned, ultra-thin, dense SWNT membranes that show above-nanometer amplitudes of vibration over a large range of frequencies spanning from 100 kHz to 5 MHz.

[Labeled leukocyte scintigraphy and total hip prosthesis]. / Scintigraphie aux leucocytes marqués et prothèse totale de hanche.

During the last few years, labelled leukocyte scintigraphy has become a decisive tool in the diagnosis of bone infections. However, this test may sometimes be deceptive as far as hip prostheses are concerned. The authors have carried out a retrospective study of 62 labelled leucocyte scintigraphies performed for suspected infection of a hip prosthesis. The comparison of the results with the different clinical, biological and radiological factors and the follow up of the patients allows determination of the sensitivity and specificity of this test which are 41% and 100% respectively. The results reported in the literature and the indications for this examination are discussed.

[Bilateral Kienbock's disease in adolescents. Apropos of a surgically treated case]. / Maladie de Kienböck bilatérale chez l'adolescent. A propos d'un cas traité chirurgicalement.

The authors report a case of bilateral idiopathic stage III Kienböck's disease. Treatment was surgical and consisted in a shortening osteotomy of the radius, with excellent clinical results. X-rays showed that osteonecrosis was stopped and both lunate bones were gradually remodelled.

[Subtalar arthrodesis for sequelae of calcaneal fractures. Apropos of 57 cases]. / Arthrodèse sous-astragalienne pour séquelles de fracture, du calcanéum. A propos de 57 cas.

PURPOSE OF THE STUDY: 57 subtalar arthrodesis for sequelae of calcaneal fractures were reviewed with a minimum follow up of 6 years 11 months. MATERIAL AND METHODS: Bone resection and interposition of bone grafts, stabilized by screws were used in 36 cases. Iliac crest grafts were used in 20 cases, cryopreserved grafts 15 times and local graft taken on the anterior tibial epiphysis once. No surgery was performed on the mid foot. RESULTS: Results were evaluated using the grading system described by Mestdagh with 33 good global results, 18 fair results and 6 poor results for a total of only 58 per cent of good global results. Of the 57 cases reviewed, 18 remained painful with a limited range of motion for inversion and eversion of the foot. In 18 patients monopodal weight-bearing was unstable. Residual oedema persisted in 5 patients. 16 patients continued to limp and 3 required the use of a crutch. 7 valgus and 3 varus deviations of the hindfoot were noted at follow up with poor tolerance of the varus when compared to exaggerated valgus. Podoscopic examination revealed increase anterior pressure zones responsible for metatarsalgia which was relieved by corrective shoe inserts in 10 patients. Radiographic evidence of fusion could be demonstrated in 55 cases. There was little or no repercussion on the tibio-talar joint. In the Chopart joint we noted 4 cases of osteoarthritis; there were 6 lesions in the talo-navicular joint and no repercussion in Lisfranc's joint. 16 complications of varying severity were noted with 2 nonunions following use of cryopreserved grafts. DISCUSSION: Subtalar arthrodesis for sequelae of traumatic lesion in the hindfoot gives good results in 2 cases out of 3. In our series, 26 per cent of the patients showed degenerative changes in the mid foot unlike the series published by Kempf. As Meary and Mestdagh noted, we found that residual varus or valgus deformity > 10 degrees was poorly tolerated as well as modifications > 20-30 degrees in the vertical ratio between the talus and the calcaneum in the horizontal plane. CONCLUSION: Subtalar arthrodesis is a useful technique giving good results in 2 out of 3 cases of traumatic sequelae in the hindfoot. Triple arthrodesis does not seem indicated when the talus and the calcaneus can be realigned before fusion. Talo-navicular arthrodesis, though more easily realized, requires blocking a normal joint in order to immobilize a painful joint.

[Effect of rotary instruments on composites for coronal restoration. A proposed evaluation protocol for the effect of rotary instruments and surface conditions]. / Action d'instruments rotatifs sur des composites de reconstitution coronaire. Propositions d'un protocole d'évaluation de l'action des instruments rotatifs et des états de surface.

Numerous core composites are used to reconstruct abutments for fixed partial dentures. The preparation is carried out with various type of burs. The purpose of this study is to facilitate the choice among them. Six chemical composites, one glass ionomer cement and two light cured composites have been selected. Calibrated samples have been made, divided into four series and prepared with six different burs used for fixed partial dentures, three of them as finishing burs. In the first part of the investigation, the samples were examined with a S.E.M., in order to visualize the surface texture. According to the materials used, variations may exist. In the second part of the investigation, a tridimensional study was performed using a mechanical scanner microscope which permitted the quantification of some roughness characteristics, thus, an objective comparison of the surfaces became possible. Due to the complementary nature of the two investigation techniques, a protocol is presented for the study of burs instrumentation and prepared tooth surface.

[Modalities of the care of acute non-severe infantile diarrhea as a function of the place of care. Prospective study during a winter epidemic]. / Modalités de prise en charge de la diarrhée aiguë non grave du nourrisson en fonction des filiéres de soin. Etude prospective 3u cours dúne epidémie hivernale.

Seventeen pediatricians and 34 general practitioners (GP) randomly selected in the closest area around Edouard-Herriot hospital (Lyon, France) were questioned regarding socio-economic status of families of infants who were treated for non severe acute diarrhea (loss of weight less than 10% of the initial body weight, no dehydration), and gave a copy of their prescription. During the same period, information was collected on outpatients as well as hospitalized cases of non severe acute diarrhea. Results show that in 3 months, GPs treated approximately 500 cases of non severe acute diarrhea, pediatricians 230 and the hospital 64. Oral rehydration was prescribed in 16% of diarrhea treated by GPs and 50% of those treated by pediatricians. The socio-economic status of families treated by pediatricians differed widely from those treated by GPs as well as those cared for in hospital. Vomiting as an argument for admission was found in 55% of referrals.

[Neuroblastoma in the Rhone-Alpes area: epidemiologic data]. / Le neuroblastome dans la région Rhône-Alpes: données épidémiologiques.

An epidemiological study of neuroblastoma in the Rhône-Alpes area was carried out over a 5 year period. The aim was to set up a background for a screening program in order to increase the number of neuroblastoma diagnosed in children before age 1, and decrease or eliminate advanced stage neuroblastomas.