Three Dimensional Analysis of Intraoral Scanners Accuracy: An In-Vitro Study

Purpose: To evaluate and compare the accuracy of two intraoral scanners (IOS) for partial and complete coverage tooth preparations in the presence and absence of adjacent teeth using three-dimensional (3D) comparisons. Materials and Methods: Eight different complete coverage (CC) and partial coverage (PC) tooth preparations were scanned by two IOS, the Trios (TRI) IOS from 3Shape and the True Definition (TRU) IOS from 3M. All teeth preparations were scanned with the IOS in the presence and absence of adjacent teeth. Four groups were established for each scanner; Group 1: PC preparations with adjacent teeth. Group 2: CC preparations with adjacent teeth. Group 3: PC preparations without adjacent teeth. Group 4: CC preparations without adjacent teeth. 3D analysis was performed on scanned preparations using 3D compare software to examine average absolute discrepancy (AAD) and maximum absolute discrepancy (MAD). A Two-way ANOVA was performed followed by a post-hoc Tukey’s test HSD to evaluate the effect of adjacent teeth, preparation design, and the type of intraoral scanner used Results: For TRI IOS, the AAD for Groups 1, 2, 3, and 4 were 20.0±1.8 μm, 19.6±2.4 μm, 15.5±2.7 μm, and 12.9±1.4 μm respectively, whereas the MAD for groups 1, 2, 3, and 4 were 109.7±13.5 μm, 93.2±8.9 μm, 85.6±16.1 μm, and 66.0±11.2 μm respectively. For TRU IOS, the AAD for Groups 1, 2, 3, and 4 were 22.1±3.7 μm, 17.9±2.0 μm, 20.1±5.9 μm, and 14.9±1.8 μm respectively, whereas the MAD for groups 1, 2, 3, and 4 were 130.6±38.5 μm, 92.7±13.5 μm, 89.1±20.4 μm, and 68.0±11.8 μm respectively. Two-way ANOVA showed statistically significant differences between the AAD and MAD of both TRI and TRU IOS (P\u3c .001), as well as the presence or absence of adjacent teeth (P \u3c.001) and preparation design (P\u3c.001). Conclusions: Within the limitations of this study, PC preparation scans exhibited lower accuracy than CC scans. In addition, the presence of adjacent teeth decreased the accuracy of both IOS. Comparable accuracy for CC preparation scans were found for both IOS, with the TRI IOS having better accuracy for PC preparation scans

Digitizing and 3D Modeling of Urban Environments and Roads using Vehicle-Borne Laser Scanner System

International audience—In this paper we present a system for three-dimensional environment modeling. It consists of an instrumented vehicle equipped with a 2D laser range scanner for data mapping, and GPS, INS and odometers for vehicle positioning and attitude information. The advantage of this system is its ability to perform data acquisition during the vehicle navigation; the sensor needed being a basic 2D scanner with opposition to traditional expensive 3D sensors. This system integrates the laser raw range data with the vehicle's internal state estimator and is capable of reconstructing the 3D geometry of the environment by real-time geo-referencing. We propose a high level representation of the urban scene while identifying automatically and in real time some types of existing objects in this environment. Thus, our modeling is articulated around three principal axes, the segmentation; decimation; the 3D reconstruction and visualization. The road is the most important object for us; some road features like the curvature and the width are extracted

Real time trajectory prediction for collision risk estimation between vehicles

International audienceIn this paper, we present our approach for collision risk estimation between vehicles. The vehicles are equipped with GPS receivers and communication devices. Our approach consists on using the knowledge given trough communication tool to predict the trajectories of the surrounding vehicles. Based on these trajectories, we identify the configurations of the collisions between vehicles. The risk is calculated using several indicators that are reflecting not only the possible collisions but also the dangerousness of these collisions. Our algorithm is tested on crossroads using scenarios involving real prototypes producing realistic scenario

Axl/Gas6/NFκB signalling in schwannoma pathological proliferation, adhesion and survival.

TAM family receptor tyrosine kinases comprising Tyro3 (Sky), Axl, and Mer are overexpressed in some cancers, correlate with multidrug resistance and contribute to tumourigenesis by regulating invasion, angiogenesis, cell survival and tumour growth. Mutations in the gene coding for a tumour suppressor merlin cause development of multiple tumours of the nervous system such as schwannomas, meningiomas and ependymomas occurring spontaneously or as part of a hereditary disease neurofibromatosis type 2. The benign character of merlin-deficient tumours makes them less responsive to chemotherapy. We previously showed that, amongst other growth factor receptors, TAM family receptors (Tyro3, Axl and Mer) are significantly overexpressed in schwannoma tissues. As Axl is negatively regulated by merlin and positively regulated by E3 ubiquitin ligase CRL4DCAF1, previously shown to be a key regulator in schwannoma growth we hypothesized that Axl is a good target to study in merlin-deficient tumours. Moreover, Axl positively regulates the oncogene Yes-associated protein, which is known to be under merlin regulation in schwannoma and is involved in increased proliferation of merlin-deficient meningioma and mesothelioma. Here, we demonstrated strong overexpression and activation of Axl receptor as well as its ligand Gas6 in human schwannoma primary cells compared to normal Schwann cells. We show that Gas6 is mitogenic and increases schwannoma cell-matrix adhesion and survival acting via Axl in schwannoma cells. Stimulation of the Gas6/Axl signalling pathway recruits Src, focal adhesion kinase (FAK) and NFκB. We showed that NFκB mediates Gas6/Axl-mediated overexpression of survivin, cyclin D1 and FAK, leading to enhanced survival, cell-matrix adhesion and proliferation of schwannoma. We conclude that Axl/FAK/Src/NFκB pathway is relevant in merlin-deficient tumours and is a potential therapeutic target for schwannoma and other merlin-deficient tumours

Modulowatt : description d'un système innovant de recharge de véhicule électrique

National audienceCe papier présente l'architecture d'un système innovant de recharge de véhicules électriques. Ce système tente de répondre d'une façon systémique aux éléments freins à l'introduction du véhicule électrique dans l'espace urbain. Basé sur le concept de connexion automatique mains libres, le système Modulowatt (infrastructure de recharge + système embarqué dans les véhicules) propose un domaine d'applications à plusieurs innovations étudiées dans le cadre des systèmes de transports intelligents comme la conduite autonome, la communication V2I et V2V, la perception, etc. Ce papier présente une partie de ces innovations réalisée dans le cadre d'un démonstrateur présentée au salon de l'automobile 2010 de Paris

The scaffold protein KSR1, a novel therapeutic target for the treatment of Merlin-deficient tumors

Merlin has broad tumor-suppressor functions as its mutations have been identified in multiple benign tumors and malignant cancers. In all schwannomas, the majority of meningiomas and 1/3 of ependymomas Merlin loss is causative. In neurofibromatosis type 2, a dominantly inherited tumor disease because of the loss of Merlin, patients suffer from multiple nervous system tumors and die on average around age 40. Chemotherapy is not effective and tumor localization and multiplicity make surgery and radiosurgery challenging and morbidity is often considerable. Thus, a new therapeutic approach is needed for these tumors. Using a primary human in vitro model for Merlin-deficient tumors, we report that the Ras/Raf/mitogen-activated protein, extracellular signal-regulated kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) scaffold, kinase suppressor of Ras 1 (KSR1), has a vital role in promoting schwannomas development. We show that KSR1 overexpression is involved in many pathological phenotypes caused by Merlin loss, namely multipolar morphology, enhanced cell-matrix adhesion, focal adhesion and, most importantly, increased proliferation and survival. Our data demonstrate that KSR1 has a wider role than MEK1/2 in the development of schwannomas because adhesion is more dependent on KSR1 than MEK1/2. Immunoprecipitation analysis reveals that KSR1 is a novel binding partner of Merlin, which suppresses KSR1's function by inhibiting the binding between KSR1 and c-Raf. Our proteomic analysis also demonstrates that KSR1 interacts with several Merlin downstream effectors, including E3 ubiquitin ligase CRL4DCAF1. Further functional studies suggests that KSR1 and DCAF1 may co-operate to regulate schwannomas formation. Taken together, these findings suggest that KSR1 serves as a potential therapeutic target for Merlin-deficient tumors

The role of insulin-like growth factors signaling in merlin-deficient human schwannomas.

Loss of the tumor suppressor merlin causes development of the tumors of the nervous system, such as schwannomas, meningiomas, and ependymomas occurring spontaneously or as part of a hereditary disease Neurofibromatosis Type 2 (NF2). Current therapies, (radio) surgery, are not always effective. Therefore, there is a need for drug treatments for these tumors. Schwannomas are the most frequent of merlin-deficient tumors and are hallmark for NF2. Using our in vitro human schwannoma model, we demonstrated that merlin-deficiency leads to increased proliferation, cell-matrix adhesion, and survival. Increased proliferation due to strong activation of extracellular-signal-regulated kinase 1/2 (ERK1/2) is caused by overexpression/activation of platelet-derived growth factor receptor-β (PDGFR-β) and ErbB2/3 which we successfully blocked with AZD6244, sorafenib, or lapatinib. Schwannoma basal proliferation is, however, only partly dependent on PDGFR-β and is completely independent of ErbB2/3. Moreover, the mechanisms underlying pathological cell-matrix adhesion and survival of schwannoma cells are still not fully understood. Here, we demonstrate that insulin-like growth factor-I receptor (IGF-IR) is strongly overexpressed and activated in human primary schwannoma cells. IGF-I and -II are overexpressed and released from schwannoma cells. We show that ERK1/2 is relevant for IGF-I-mediated increase in proliferation and cell-matrix adhesion, c-Jun N-terminal kinases for increased proliferation and AKT for survival. We demonstrate new mechanisms involved in increased basal proliferation, cell-matrix adhesion, and survival of schwannoma cells. We identified therapeutic targets IGF-IR and downstream PI3K for treatment of schwannoma and other merlin-deficient tumors and show usefulness of small molecule inhibitors in our model. PI3K is relevant for both IGF-IR and previously described PDGFR-β signaling in schwannoma

A Hybrid Control for Automatic Docking of Electric Vehicles for recharging

International audienceIn this paper, we present the architecture of an innovative docking station for electric vehicles recharging and a hybrid control scheme for automatic docking of the vehicles. This work is a part of on-going project concerning the development of a smart charging station for electric vehicles equipped with an automated arm, which connect the vehicle to the charging station, and an infrared beacon system for localizing the automatically maneuvering vehicle in the docking area. The proposed control scheme combines time-optimal (bang-bang) control with continuous time-invariant nonlinear control, which stabilizes the vehicle to a small neighborhood of the docking point. Simulation and experimental results illustrate the effectiveness of the proposed controller