CHAMBRES PROPORTIONNELLES SOUMISES À DE HAUTS FLUX

Nous présentons les différents problèmes rencontrés lors de l'utilisation de chambres proportionnelles dans des faisceaux de 108 particules/seconde. Une revue de différentes mesures expérimentales de l'efficacité est donnée

Documentation of baseline and policy scenarios for Test Case 1

Environmental Economics and Policy,

Analysis of Center of Mass and Gravity-Induced Vertebral Axial Torque on the Scoliotic Spine by Barycentremetry

STUDY DESIGN: Retrospective observational study. OBJECTIVES: To determine the mass distribution along the scoliotic trunk using barycentremetry and its relationship with vertebral axial rotation and torque. SUMMARY OF THE BACKGROUND DATA: Deformity progression in adolescent idiopathic scoliosis (AIS) is not yet fully understood, but gravity load on the spine could play a role. Barycentremetry allows to characterize body mass distribution in standing position, which could provide a better understanding the mechanisms of progression. METHODS: 81 subjects (27 healthy adolescents and 53 AIS patients) underwent biplanar radiography and 3D reconstruction of the spine and body envelope. Position of the gravity line was estimated, as well as trunk segmental centers of mass COMs at each vertebral level and resulting axial torques to each vertebra. RESULTS: The COM of all trunk segments was less than 1 cm from the gravity line in the frontal plane for healthy subjects, and less than 1.5 cm for AIS patients. Vertebral axial torque was 0.7 ± 0.5 Nm in healthy subjects, 2.9 ± 2.1 Nm at the junctional vertebrae of AIS patients and 0.5 ± 0.5 at the apex. A strong association was found between high torque and high intervertebral rotation at junctions, with low torque and low intervertebral axial rotation at the apex. CONCLUSION: Results suggest that AIS patients can maintain the COM of each body segment close to their gravity line, irrespective of the severity and asymmetry of their deformity. Moreover, torque analysis shed some light on the importance of junctional vertebrae in the spinal deformity and, potentially, in the vicious cycle determining scoliosis progression. LEVEL OF EVIDENCE: Level III.The authors are grateful to the ParisTech BiomecAM chair program on subject-specific musculoskeletal model- ling (with the support of ParisTech and Yves Cotrel Foundations, Société Géenérale, Proteor, and Covea

The major characteristics of environmental policies and agro-ecological technologies to be studied in Test case 2

Agricultural and Food Policy, Environmental Economics and Policy, Farm Management, Land Economics/Use,

SEARCH FOR NEUTRINO OSCILLATION AT BUGEY

The high flux of low energy [MATH]e produced by the core of a PWR reactor of Bugey power plant has been used to search for evidence of neutrino oscillations through the inverse beta decay reaction [MATH]e + p → e+ + n. Measurements have been performed at two distances (13.5 and 18.5m). About 50 000 [MATH]e events have been collected at the first position and 25 000 [MATH]e events at the second one. Data analysis is almost completed

A Cellular Potts energy-based approach to analyse the influence of the surface topography on single cell motility

cellular scale level, the cell behaviour, especially its migration, is affected by the specificities of the surface of the substrate, such as the stiffness of the surface and its roughness topography. The latter has been shown to have a great impact on various cell mechanisms, such as the cell adhesion, migration, or proliferation. In fact, the mere presence of micro roughness leads to an improvement of those mechanisms, with a better integration of the implants. However, the phenomena behind those improvements are still not clear. In this paper, we propose a three-dimensional (3D) model of a single cell migration using a Cellular Potts (CP) model to study the influence of the surface topography on cell motility. To do so, various configurations were tested, such as: (i) a substrate with a random roughness, (ii) a substrate with a rectangular groove pattern (parallel and perpendicular to the direction of motion), (ii) a substrate with a sinusoidal groove pattern. To evaluate the influence of the surface topography on cell motility, for each configuration, the cell speed and shape as well as the contact surface between the cell and the substrate have been quantified. Our numerical results demonstrate that, in agreement with the experimental observations of the literature, the substrate topography has an influence on the cell efficiency (i.e. cell speed), orientation and shape. Besides, we also show that the increase of the contact surface alone in presence of roughness is not enough to explain the improvement of cell migration on the various rough surfaces. Finally, we highlight the importance of the roughness dimension on cell motility. This could be a critical aspect to consider for further analyses and applications, such as surface treatments for medical applications.This work has been funded by RNC Santé of Arts et Métiers, supporting the first author through a PhD scholarshi

Mobiliser les principes de l'agroécologie pour redéfinir le cadre d'analyse et d'évaluation des systèmes ovins en zone Roquefort

Dans le Rayon Roquefort, l'intensification de la production laitière avec l'utilisation du progrès génétique de la race Lacaune a entrainé une augmentation des achats d'aliments et d'intrants dans les élevages. Les résultats économiques des élevages ovins lait se retrouvent directement dépendants des prix des céréales, des engrais et du fuel, prix en constante augmentation et de plus en plus fluctuants compte tenu d'évènements climatiques extrêmes de plus en plus fréquents

Coronal Trunk Imbalance in Idiopathic Scoliosis: Does Gravity Line Localisation Confirm the Physical Findings?

Background: Adolescent idiopathic scoliosis (AIS) can require surgical procedures that have major con-sequences. Coronal imbalance as assessed clinically using a plumb line is a key criterion for selecting patients to surgery. Nevertheless, the reference standard for assessing postural balance of the trunk is gravity line localisation within a validated frame of reference. Recent studies have established that the gravity line can be localised after body contour reconstruction from biplanar radiographs. The objec-tive of this study was to validate a gravity line localisation method based on biplanar radiographs in a population with AIS then to validate gravity line position versus plumb line position. Hypothesis: Plumb line and gravity line assessments of coronal balance correlate with each other. Material and methods: A gravity line localisation method based on biplanar radiography was validated in 14 patients with AIS versus force platform as the method of reference. Normal plumb line and gravity line positions were determined in 27 asymptomatic adolescents using biplanar radiography. The results of the two methods were then compared in 53 patients with AIS. Results: The reliability of gravity line localisation in the coronal plane based on biplanar radiography was 2.4 mm (95% confidence interval). The distance between the gravity line and the middle of the line connecting the centres of the two femoral heads (HA) showed a strongly significant association with plumb line position computed as the distance from the vertical line through the middle of T1 and the centre of the S1 endplate (T1V/S): r = 0.71, p < 0.0001. Of the 20 patients with plumb line results indicating coronal imbalance, 11 (55%) had a normal gravity line-to-HA distance. Of the 33 patients with normal plumb line results, 7 (21%) had an abnormal gravity line-to-HA distance. Conclusion: The results of this study validate gravity line determination from biplanar radiographs in a population with AIS. Plumb line position correlated significantly with gravity line position but was less accurate for guiding surgical decisions. Level of evidence: IV, retrospective study.Funding source SoFCOT grant to remunerate T. Hernandez during the year of research required for the project

Guidelines for Clinical Studies with Compression Devices in Patients with Venous Disorders of the Lower Limb

Digitalitzat per Artypla