Off-line correction method suitable for a machining robotapplication to composite materials

Robotic machining finds its place in a multitude of applications with increasingly restrictive dimensional tolerances. In the machining of left-handed shapes for the production of large composite supports (four meters diameter), the expected shape accuracy is a few hundredths. The industrial robot is not initially compatible with such performance criteria. The literature possesses several ways to improve the accuracy of industrial robots such as stiffness modeling of a robot, or stress modeling with dynamic measurement of forces during machining. These methods are difficult to apply in an industrial context because they are too costly in terms of time and investments related to the means of identification. This study proposes a new off-line correction based on the mirror correction applied during machining. This method is fast and required only a 3D vision system. Moreover, it adapts to any 6-axis serial robot. The first step consists in measuring the position of the tool during a first machining operation. This measurement is then compared with the initial program setpoint to identify the robot deviation. A smart and autonomous process is used to re-edit the toolpath to compensate for the deviation. A new machining operation quantifies the correction by producing a part with improved shape tolerances. This article presents the development of the correction strategy, the implementation and the results obtained following its application in the industrial context. A gain of more than 80% is identified and an analysis of this result is proposed. Future complementary developments are suggested as perspectives

Teaching of English in French-Canada

Thesis (Ed.M.)--Boston University, 1935. This item was digitized by the Internet Archive

Grafted Human Embryonic Progenitors Expressing Neurogenin-2 Stimulate Axonal Sprouting and Improve Motor Recovery after Severe Spinal Cord Injury

7 p.Background: Spinal cord injury (SCI) is a widely spread pathology with currently no effective treatment for any symptom. Regenerative medicine through cell transplantation is a very attractive strategy and may be used in different non-exclusive ways to promote functional recovery. We investigated functional and structural outcomes after grafting human embryonic neural progenitors (hENPs) in spinal cord-lesioned rats.Methods and Principal Findings: With the objective of translation to clinics we have chosen a paradigm of delayed grafting, i.e., one week after lesion, in a severe model of spinal cord compression in adult rats. hENPs were either naive or engineered to express Neurogenin 2 (Ngn2). Moreover, we have compared integrating and non-integrating lentiviral vectors, since the latter present reduced risks of insertional mutagenesis. We show that transplantation of hENPs transduced to express Ngn2 fully restore weight support and improve functional motor recovery after severe spinal cord compression at thoracic level. This was correlated with partial restoration of serotonin innervations at lumbar level, and translocation of 5HT1A receptors to the plasma membrane of motoneurons. Since hENPs were not detectable 4 weeks after grafting, transitory expression of Ngn2 appears sufficient to achieve motor recovery and to permit axonal regeneration. Importantly, we also demonstrate that transplantation of naive hENPs is detrimental to functional recovery.Conclusions and Significance: Transplantation and short-term survival of Ngn2-expressing hENPs restore weight support after SCI and partially restore serotonin fibers density and 5HT1A receptor pattern caudal to the lesion. Moreover, grafting of naive-hENPs was found to worsen the outcome versus injured only animals, thus pointing to the possible detrimental effect of stem cell-based therapy per se in SCI. This is of major importance given the increasing number of clinical trials involving cell grafting developed for SCI patients.This study was supported by the European Union FP6 "RESCUE" STREP; the "Institut pour la Recherche sur la Moelle Epiniere"; the "Academie de Medecine"; the "Societe Francaise de Neurochirurgie"; "Verticale" and the "Association Demain Debout Aquitaine". The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Performance of the ATLAS electromagnetic calorimeter end-cap module 0

The construction and beam test results of the ATLAS electromagnetic end-cap calorimeter pre-production module 0 are presented. The stochastic term of the energy resolution is between 10% GeV^1/2 and 12.5% GeV^1/2 over the full pseudorapidity range. Position and angular resolutions are found to be in agreement with simulation. A global constant term of 0.6% is obtained in the pseudorapidity range 2.5 eta 3.2 (inner wheel)

Prise en charge chirurgicale du rachis cervical rhumatoïde (état des lieux)

L'atteinte cervicale rhumatoïde est fréquente, principalement au cours de PR érosives et séropositives.Les lésions articulaires inflammatoires sont acquises dans les 2 premières années d'évolution et auto-entretenues par l'hypermobilité engendrée.Pour les patients chez qui un traitement médical actif et rapide n'aura pas permis une stabilisation de la pathologie, l'intervention chirurgicale précoce, agressive et complète d'emblée sera le meilleur garant d'une protection voire récupération neurologique.Pourtant, une latence d'expression dans la symptomatologie et une absence de corrélation radio-clinique rendent ardue la question du timing chirurgical.En effet, l'ostéosynthèse cervicale semble profitable à tous les groupes de malades avec des résultats d'autant meilleurs que le geste sera réalisé avant les stades d'impression basilaire ou myélopathie sévère.De plus, la chirurgie de la charnière, déjà difficile et dangereuse sur un rachis sain et ce malgré l'apport de la neuronavigation par exemple est rendue plus complexe au cours de la PR par l'importance des déformations, la qualité osseuse, le risque anesthésique et les variations plus fréquentes des artères vertébrale.De ce fait, l'étude DELPHI va tenter de mettre en valeur les bénéfices d'une intervention préventive pour des patients peu symptomatiques avec des luxations modérées.Notre série rétrospective quant à elle se superpose en tous points à celles publiées précédemment dans la littérature mais met en relief un manque de rigueur dans les critères utilisés au moment de la décision chirurgicale ainsi que dans l'organisation du suivi à long terme des patients opérésMONTPELLIER-BU Médecine UPM (341722108) / SudocMONTPELLIER-BU Médecine (341722104) / SudocSudocFranceF

Potential adverse effects of cyclosporin A on kidneys after spinal cord injury

Study design:Cell transplantation strategies are gaining increasing interest for spinal cord injury (SCI) with the objective of promoting spinal cord repair. To avoid allogenic graft rejection, an adequate immune suppression is required, and one of the most potent and commonly used immunosuppressives is cyclosporin A (CsA). In SCI, permanent sensory motor loss is combined with modifications of drug absorption, distribution and elimination.Objectives:The objectives of this study were to thoroughly explore histological and functional outcomes of CsA treatment in a rat model of spinal cord compression.Setting: Experiments were carried out at the Institute for Neurosciences of Montpellier (France), the Integrative Biology of Neurodegeneration Laboratory (Spain) and in the Novartis Institutes for BioMedical Research (Switzerland) for CsA blood concentration determination.Methods:We first evaluated histological outcomes of CsA treatment on kidneys and spinal cord after SCI. We then investigated whether SCI modified CsA blood concentration. Finally, using behavioral analysis, we assessed the potential CsA impact on functional recovery.Results:When spinal-cord-injured rats were treated with a CsA dose of 10 mg kg -1 per day, we observed deleterious effects on kidneys, associated with modifications of CsA blood concentration. Adding an antibiotic treatment reduced kidney alteration without modifying CsA blood concentration. Finally, we showed that CsA treatment per se modified neither functional recovery nor lesion extension.Conclusion:This study pinpoints the absolute requirement of careful CsA monitoring in the clinical setting for patients with SCI to minimize potential unexpected effects and avoid therapeutic failure.Peer reviewe

Renvoi au comité des finances de l'examen du plan de finances de M. de Corméré, lors de la séance du 21 novembre 1789

Castellane Novejean Boniface Louis André, comte de, Cormeré Guillaume François de Mahy, baron de. Renvoi au comité des finances de l'examen du plan de finances de M. de Corméré, lors de la séance du 21 novembre 1789. In: Archives Parlementaires de 1787 à 1860 - Première série (1787-1799) Tome X - Du 12 novembre au 24 décembre 1789. Paris : Librairie Administrative P. Dupont, 1878. p. 159

Reprise de la discussion sur l'affaire du parlement de Rennes, lors de la séance du 15 décembre 1789

Estourmel Louis Marie, marquis d', Mirabeau André Boniface Louis Riqueti, vicomte de, Giraud Duplessis Pierre-Guillaume. Reprise de la discussion sur l'affaire du parlement de Rennes, lors de la séance du 15 décembre 1789. In: Archives Parlementaires de 1787 à 1860 - Première série (1787-1799) Tome X - Du 12 novembre au 24 décembre 1789. Paris : Librairie Administrative P. Dupont, 1878. p. 591

Reprise de la discussion sur l'affaire du parlement de Rennes, lors de la séance du 15 décembre 1789

Estourmel Louis Marie, marquis d', Mirabeau André Boniface Louis Riqueti, vicomte de, Giraud-Duplessis Pierre Guillaume. Reprise de la discussion sur l'affaire du parlement de Rennes, lors de la séance du 15 décembre 1789. In: Archives Parlementaires de 1787 à 1860 - Première série (1787-1799) Tome X - Du 12 novembre au 24 décembre 1789. Paris : Librairie Administrative P. Dupont, 1878. p. 591