A flood forecasting model on river Oise with the plugin mascaret

Hydrodynamic

Enabling Collaboration between Heterogeneous 3D Viewers through a PAC-C3D Modeling of the Shared Virtual Environment

International audienceWe propose to illustrate how the PAC-C3D software model makes it possible to share networked 3D Virtual Environments (VE) between heterogeneous 3D viewers written in Java3D and jReality

PAC-C3D: A New Software Architectural Model for Designing 3D Collaborative Virtual Environments

International audienceWe propose PAC-C3D as a new software model for 3D Collaborative Virtual Environments (CVE). This model merges the results from two research fields: distribution models for CVE and HCI design for computer-supported cooperative work. PAC-C3D proposes to describe each part of a shared virtual object through explicit interfaces to ensure a strong separation between the core functions of a virtual environment, its (visual) representations, and its collaborative features such as synchronization and consistency maintenance between remote users. PAC-C3D makes it possible to design a CVE with low dependency between the core functions, the distribution mode and the 3D graphics API used. It explicitly deals with the main distribution modes encountered in CVE. It makes it easy to use different 3D graphics API for different nodes involved in the same collaborative session, providing interoperability between these 3D graphics API. It also makes it possible to integrate other kinds of 3D representations such as physics engines into the CVE

Collaborative Exploration of 3D Scientific Data

International audienceThis demonstration introduces new ways for exploring Collaborative Virtual Environments (CVE) that contain 3D scientific data sets obtained by simulation. In order to make decisions accordingly to their collective knowledge and understanding of the simulation, the users must collaborate and share experiences and comments. We provide tools to enable a good coordination between the users, and to make each user aware of the activity of others. Each user can navigate within the CVE: change her own position, orientation and scale. Each user can also add annotations within the virtual universe. We propose several 3D layouts for the presentation of the data, associated with different 3D navigation tools. Consequently, the user can explore the data accoording to various parameters such as time or temperature. Last we propose a new 3D interaction tool, called 2D Cursor / 3D Pointer, dedicated to selection and manipulation of 3D objects, and application control. This 2D cursor is associated with a 3D geometry in order to make people aware of the activity of the users who are using this tool

Guiding Techniques for Collaborative Exploration in Multi-Scale Shared Virtual Environments

International audienceExploration of large-scale 3D Virtual Environments (VEs) is difficult because of lack of familiarity with complex virtual worlds, lack of spatial information that can be offered to users and lack of sensory (visual, auditory, locomotive) details compared to exploration of real environments. To address this problem, we present a set of metaphors for assisting users in collaborative navigation to perform common exploration tasks in shared collaborative virtual environments. Our propositions consist in three guiding techniques in the form of navigation aids to enable one or several users (called helping user(s)) to help one main user (called exploring user) to explore the VE efficiently. These three techniques consist in drawing directional arrows, lighting up path to follow, and orienting a compass to show a direction to the exploring user. All the three techniques are generic so they can be used for any kind of 3D VE, and they do not affect the main structure of the VE so its integrity is guaranteed. To compare the efficiency of these three guiding techniques, we have conducted an experimental study of a collaborative task whose aim was to find hidden target objects in a complex and multi-scale shared 3D VE. Our results show that although the directional arrows and compass surpassed the light source for the navigation task, these three techniques are completely appropriate for guiding a user in 3D complex VEs

Use of neuraminidase inhibitors in primary health care during pandemic and seasonal influenza between 2009 and 2013: Outpatient influenza antiviral treatment

International audienceBACKGROUND:In a context of controversy about influenza antiviral treatments, this study assessed primary health-care physicians' prescription of neuraminidase inhibitors (NIs) in France during pandemic and seasonal influenza between 2009 and 2013.METHODS:This observational study, using data recorded in three national databases, estimated the rate of NI prescription among influenza-like illness (ILI) patients seen in GP and paediatrician consultations, and determined factors associated with this prescription according to a multivariate analysis. NI delivery by pharmacists was also evaluated.RESULTS:Rates of NI prescription were estimated to be 61.1% among ILI patients with a severe influenza risk factor seen in GP consultation during the A(H1N1)pdm2009 pandemic versus an average rate of 25.9% during the three following seasonal influenza epidemics. Factors associated with NI prescription were a chronic disease in patients under 65 years (OR 14.85; 95% CI 13.00, 16.97) and in those aged 65 and older (OR 7.54; 5.86, 9.70), an age ≥65 years in patients without chronic disease (OR 1.35; 1.04, 1.74), a pregnancy (OR 10.63; 7.67, 15.76), obesity (OR 4.67; 3.50, 6.22) and a consultation during the pandemic A(H1N1)pdm2009 (OR 3.19; 2.93, 3.48). The number of antiviral treatments delivered by pharmacists during the A(H1N1)pdm2009 pandemic was 835 per 100,000 inhabitants, and an average of 275 per 100,000 inhabitants during the three following seasonal influenza epidemics.CONCLUSIONS:Although physicians seem to follow the recommended indications for NIs in primary health-care practice, this study confirms the low rate of NI prescription to ILI patients with a severe influenza risk factor, especially during seasonal epidemics

Roles of fibrin α- and γ-chain specific cross-linking by FXIIIa in fibrin structure and function

Factor XIII is responsible for the cross-linking of fibrin γ-chains in the early stages of clot formation, whilst α-chain cross-linking occurs at a slower rate. Although γ- and α-chain cross-linking was previously shown to contribute to clot stiffness, the role of cross-linking of both chains in determining clot structure is currently unknown. Therefore, the aim of this study was to determine the role of individual α- and γ-chain cross-linking during clot formation, and its effects on clot structure. We made use of a recombinant fibrinogen (γQ398N/Q399N/K406R), which does not allow for γ-chain cross-linking. In the absence of cross-linking, intact D-D interface was shown to play a potential role in fibre appearance time, clot stiffness and elasticity. Cross-linking of the fibrin α-chain played a role in the thickening of the fibrin fibres over time, and decreased lysis rate in the absence of α2-antiplasmin. We also showed that α-chain cross-linking played a role in the timing of fibre appearance, straightening fibres, increasing clot stiffness and reducing clot deformation. Cross-linking of the γ-chain played a role in fibrin fibre appearance time and fibre density. Our results show that α- and γ-chain cross-linking play independent and specific roles in fibrin clot formation and structure

Fibrinogen splice variation and cross-linking: Effects on fibrin structure/function and role of fibrinogen γ’ as thrombomobulin II

Fibrin is an important matrix protein that provides the backbone to the blood clot, promoting tissue repair and wound healing. Its precursor fibrinogen is one of the most heterogenous proteins, with an estimated 1 million different forms due to alterations in glycosylation, oxidation, single nucleotide polymorphisms, splice variation and other variations. Furthermore, ligation by transglutamimase factor XIII (cross-linking) adds to the complexity of the fibrin network. The structure and function of the fibrin network is in part determined by this natural variation in the fibrinogen molecule, with major effects from slice variation and cross-linking. This mini-review will discuss the direct effects of fibrinogen αEC and fibrinogen γ’ splice variation on clot structure and function and also discuss the additional role of fibrinogen γ’ as thrombomodulin II. Furthermore, the effects of cross-linking on clot function will be described. Splice variation and cross-linking are major determinants of the structure and function of fibrin and may therefore impact on diseases affecting bleeding, thrombosis and tissue repair