Bone microarchitecture in human foetuses

articleBone microarchitecture is receiving increasing attention in theassessment of the biomechanical properties of bone. While it iswell characterized in normal and pathologic human subjects,few quantitative data are available in human fetal development.In this paper, quantitative parameters of bone microarchitecturein developing human bone are reviewed from the literature andsupplemented by new data from the femoral metaphysis of hu-man fetuses. The samples were imaged using synchrotron radi-ation 3D micro-CT and processed using customized analysismethods. This technique provides 3D model independent mor-phometric parameters, anisotropy, connectivity and geometrycharacteristics, as well as information on mineralization.The morphometric parameters obtained on fetal vertebrae andfemurs evidenced a dense trabecular structure as comparedto that of young adults. The histomorphometric and the 3D mi-cro-CT analysis were consistent to show a significant in-crease of trabecular bone volume with gestational age. Tra-becular bone was found isotropic in vertebral bodies andanisotropic in femoral metaphysis, demonstrating a radialgrowth in vertebrae, and a longitudinal spreading out in longbones such as the femurs. Trabecular thickness in the maturebone of vertebral body and femoral metaphysis was around100 μm, which was in agreement with histomorphometric eval-uation. In the femoral metaphysis, three-dimensional analysisconfirmed the thickening of trabeculae with the distance tothe growth plate, and an estimated rate of thickening around 3μm/day previously obtained in histomorphometry. The 3D net-work was highly connected, and our new geometrical analysistechnique showed a strong prevalence of rod structure ascompared to the plate structure in cancellous bone

Les inhumations de la nécropole Hallstatt final de Basly (Calvados), approche biologique et sociale

La fouille de la nécropole de Basly (Calvados - France) a livré 14 sépultures à inhumation datées de la fin du premier âge du Fer (Hallstatt D1-D2). Les sépultures apparaissent organisées en trois groupes répartis à l’intérieur et autour d’un enclos carré. L’étude archéologique avait révélé en son temps des différences sur de nombreux aspects de la sépulture (forme et organisation de la fosse, mobilier, etc.). L’étude anthropologique présentée ici a porté sur la détermination du sexe et les estimations de l’âge au décès et de l’état sanitaire à partir du squelette et notamment des dents, de la stature et finalement une étude des variations non métriques. Les résultats, reliés à l’organisation du site et à sa dimension sociale, ont conduit à proposer l’hypothèse de différences de richesse et de hiérarchisation somme toute peu marquées, et certains éléments contradictoires, montrés par la combinaison des deux types d’étude, ne nous permettent pas de comprendre le statut de certains inhumés.The inhumations in the Basly late Hallstatt cemetery (Calvados), a biological and social approach.The excavation of the cemetery of Basly (Calvados - France) produced 14 inhumation burials dating from the end of the first Iron Age (Hallstatt D1-D2). The burials appeared to be organized in three groups in and around a square ditch. The archaeological study had revealed that differences existed in many aspects of the burial (type of organization, burial goods, etc.). The anthropological study included the estimation of sex, age at death and stature of the deceased, as well as determination of health status using teeth and skeleton, and finally a study of non-metrical variations. The results, related to the organization of the site and its social dimension, led to the hypothesis that a social differenciation existed beyond death and is thus still visible today. The combination of the two types of studies also showed some contradictions that we are not yet able to understand in the status of some of the deceased

Trois sépultures atypiques du Second âge du Fer à Reviers (Calvados)

Trois sépultures du Second âge du Fer, mises au jour en 2000 à Reviers (Calvados), montrent un mode d’inhumation inhabituel. Chacun des individus, adulte, a été enterré assis dans une fosse circulaire, avec les membres fléchis et le haut du corps penché vers l’avant. Après une étude précise des positions d’inhumation et des propositions de restitution de l’espace de décomposition des cadavres, nous établissons une comparaison avec des sites cultuels ayant livré des os humains erratiques ou non et les individus inhumés en position assise. Au terme de cette étude, l’interprétation de ce type de sépulture pose toujours problème.Three Second Iron Age burials, found in 2000 in Reviers (Calvados – France), show an uncommon type of inhumation. Every individual, of an adult age, was buried sitting in a circular pit, limbs bent and the upper half of the body leaning forward. After studying the position of each individual and proposing a reproduction of the decomposition space of the corpses, we compare these burials with worshiping sites yielding human remains and sitting individuals. This comparison done, we find that the interpretation of this type of burial remains problematic

A Wearable Sensor Network for Gait Analysis: A 6-Day Experiment of Running Through the Desert

International audienceThis paper presents a new system for analysis of walking and running gaits. The system is based on a network of wireless nodes with various types of embedded sensors. It has been designed to allow long-term recording in outdoor environments and was tested during the 2010 "Sultan Marathon des Sables" desert race. A runner was fitted with the sensory network for six days of the competition. Although technical problems have limited the amount of data recorded, the experiment was nevertheless suc- cessful: the system did not interfere with the runner, who finished with a high ranking, the concept was validated and high quality data were ac- quired. It should be noted that the loss of some of the measurements was mainly due to problems with the cable connectors between the nodes and batteries. In this paper, we describe the technical aspects of the system developed, the experimental conditions under which it was validated, and give examples of the data obtained with some preliminary processing

Occupancy grids from stereo and optical flow data

voir basilic : http://emotion.inrialpes.fr/bibemotion/2006/BPUCL06/ address: Rio de Janeiro (BR)In this paper, we propose a real-time method to detect obstacles using theoretical models of the ground plane, first in a 3D point cloud given by a stereo camera, and then in an optical flow field given by one of the stereo pair's camera. The idea of our method is to combine two partial occupancy grids from both sensor modalities with an occupancy grid framework. The two methods do not have the same range, precision and resolution. For example, the stereo method is precise for close objects but cannot see further than 7 m (with our lenses), while the optical flow method can see considerably further but has lower accuracy. Experiments that have been carried on the CyCab mobile robot and on a tractor demonstrate that we can combine the advantages of both algorithms to build local occupancy grids from incomplete data (optical flow from a monocular camera cannot give depth information without time integration)

Treatment of major depression

Stress and Psychopatholog