Perceptually-Informed Virtual Environment (PerceiVE) Design Tool

Virtual environments (VE\u27s) are becoming more and more prevalent as training tools for both military and civilian applications. The common assumption is that the more realistic the VE, the better the transfer of training to real world tasks. However, some aspects of task content and fidelity may result in stronger transfer of training than even the most high fidelity simulations. This research effort seeks to demonstrate the technical feasibility of a Perceptually-informed Virtual Environment (PerceiVE) Design Tool, capable of dynamically detecting changes in operator behavior and physiology throughout a VE experience and comparing those changes to operator behavior and physiology in real-world tasks. This approach could potentially determine which aspects of VE fidelity will have the highest impact on transfer of training. A preliminary study was conducted in which psychophysiological and performance data were compared for a visual search tasks with low and high fidelity conditions. While no significant performance effects were found across conditions, event-related potential (ERP) data revealed significant differences between the low and high fidelity stimulus conditions. These results suggest that psychophysiological measures may provide a more sensitive and objective measure for determining VE fidelity requirements. © 2009 Springer

Clinical and Molecular Spectrum of Nonsyndromic Early-Onset Osteoarthritis

International audienceObjective: Osteoarthritis (OA) is the most common joint disease worldwide. The etiology of OA is varied, ranging from multifactorial to environmental to monogenic. In a condition called early-onset OA, OA occurs at an earlier age than is typical in the general population. To our knowledge, there have been no large-scale genetic studies of individuals with early-onset OA. The present study was undertaken to investigate causes of monogenic OA in individuals with nonsyndromic early-onset OA. Methods: The study probands were 45 patients with nonsyndromic early-onset OA who were referred to our skeletal disease center by skeletal dysplasia experts between 2013 and 2019. Criteria for early-onset OA included radiographic evidence, body mass index ≤30 kg/m2, age at onset ≤50 years, and involvement of ≥1 joint site. Molecular analysis was performed with a next-generation sequencing panel. Results: We identified a genetic variant in 13 probands (29%); the affected gene was COL2A1 in 11, ACAN in 1, and SLC26A2 in 1. After familial segregation analysis, 20 additional individuals were identified. The mean ± SD age at onset of joint pain was 19.5 ± 3.9 years (95% confidence interval 3–47). Eighteen of 33 subjects (55%) with nonsyndromic early-onset OA and a genetic variant had had at least 1 joint replacement (mean ± SD age at first joint replacement 41 ± 4.2 years; mean number of joint replacements 2.6 per individual), and 21 (45%) of the joint replacement surgeries were performed when the patient was andlt;45 years old. Of the 20 patients age andgt;40 years, 17 (85%) had had at least 1 joint replacement. Conclusion: We confirmed that COL2A1 is the main monogenic cause of nonsyndromic early-onset OA. However, on the basis of genetic heterogeneity of early-onset OA, we recommend next-generation sequencing for all individuals who undergo joint replacement prior to the age of 45 years. Lifestyle recommendations for prevention should be implemented