University of Nice Sophia Antipolis

About: University of Nice Sophia Antipolis is a education organization based out in Nice, France. It is known for research contribution in the topics: Population & Stars. The organization has 10291 authors who have published 19964 publications receiving 680762 citations. The organization is also known as: UNS & University of Nice-Sophia Antipolis.

Sensitivity and specificity of dopamine transporter imaging with 123I-FP-CIT SPECT in dementia with Lewy bodies: a phase III, multicentre study

Abstract: Summary Background Dementia with Lewy bodies (DLB) needs to be distinguished from other types of dementia because of important differences in patient management and outcome. Current clinically based diagnostic criteria for DLB have limited accuracy. Severe nigrostriatal dopaminergic degeneration occurs in DLB, but not in Alzheimer's disease or most other dementia subtypes, offering a potential system for a biological diagnostic marker. The primary aim of this study was to investigate the sensitivity and specificity, in the ante-mortem differentiation of probable DLB from other causes of dementia, of single photon emission computed tomography (SPECT) brain imaging with the ligand 123 I-2β-carbometoxy-3β-(4-iodophenyl)-N-(3-fluoropropyl) nortropane ( 123 I-FP-CIT), which binds to the dopamine transporter (DAT) reuptake site. Diagnostic accuracy, positive and negative predictive values, and inter-reader agreement were the secondary endpoints and a subgroup of possible DLB patients was also included. Methods We did a phase III study in which we used a 123 I-FP-CIT SPECT scan to assess 326 patients with clinical diagnoses of probable (n=94) or possible (n=57) DLB or non-DLB dementia (n=147) established by a consensus panel (in 28 patients no diagnosis could be made). Three readers, unaware of the clinical diagnosis, classified the images as normal or abnormal by visual inspection. The study had 90% power to detect the differences between our anticipated sensitivity (0·80) and specificity (0·85) targets and prespecified lower thresholds (sensitivity 0·65, specificity 0·73) using one-sided binomial tests with a significance level of α=0·025. Findings Abnormal scans had a mean sensitivity of 77·7% for detecting clinical probable DLB, with specificity of 90·4% for excluding non-DLB dementia, which was predominantly due to Alzheimer's disease. A mean value of 85·7% was achieved for overall diagnostic accuracy, 82·4% for positive predictive value, and 87·5% for negative predictive value. Inter-reader agreement for rating scans as normal or abnormal was high (Cohen's κ=0·87). The procedure was well tolerated with few adverse events. Interpretation A revision of the International Consensus Criteria for DLB has recommended that low DAT uptake in the basal ganglia, as shown by SPECT or PET imaging, be a suggestive feature for diagnosis. Our findings confirm the high correlation between abnormal (low binding) DAT activity measured with 123 I-FP-CIT SPECT and a clinical diagnosis of probable DLB. The diagnostic accuracy is sufficiently high for this technique to be clinically useful in distinguishing DLB from Alzheimer's disease.

Serious Games, Debriefing, and Simulation/Gaming as a Discipline

Abstract: At the close of the 40th Anniversary Symposium of S&G, this editorial offers some thoughts on a few important themes related to simulation/gaming. These are development of the field, the notion of serious games, the importance of debriefing, the need for research, and the emergence of a discipline. I suggest that the serious gaming community has much to offer the discipline of simulation/gaming and that debriefing is vital both for learning and for establishing simulation/gaming as a discipline.

Reconstructing routes of invasion using genetic data: why, how and so what?

Abstract: Detailed knowledge about the geographical pathways followed by propagules from their source to the invading populations—referred to here as routes of invasion—provides information about the history of the invasion process and the origin and genetic composition of the invading populations. The reconstruction of invasion routes is required for defining and testing different hypotheses concerning the environmental and evolutionary factors responsible for biological invasions. In practical terms, it facilitates the design of strategies for controlling or preventing invasions. Most of our knowledge about the introduction routes of invasive species is derived from historical and observational data, which are often sparse, incomplete and, sometimes, misleading. In this context, population genetics has proved a useful approach for reconstructing routes of introduction, highlighting the complexity and the often counterintuitive nature of the true story. This approach has proved particularly useful since the recent development of new model-based methods, such as approximate Bayesian computation, making it possible to make quantitative inferences in the complex evolutionary scenarios typically encountered in invasive species. In this review, we summarize some of the fundamental aspects of routes of invasion, explain why the reconstruction of these routes is useful for addressing both practical and theoretical questions, and comment on the various reconstruction methods available. Finally, we consider the main insights obtained to date from studies of invasion routes.

Dynamic simulation of hydrodynamically interacting particles

Abstract: A general method for computing the hydrodynamic interactions among N suspended particles, under the condition of vanishingly small particle Reynolds number, is presented. The method accounts for both near-field lubrication effects and the dominant many-body interactions. The many-body hydrodynamic interactions reproduce the screening characteristic of porous media and the ‘effective viscosity’ of free suspensions. The method is accurate and computationally efficient, permitting the dynamic simulation of arbitrarily configured many-particle systems. The hydrodynamic interactions calculated are shown to agree well with available exact calculations for small numbers of particles and to reproduce slender-body theory for linear chains of particles. The method can be used to determine static (i.e. configuration specific) and dynamic properties of suspended particles that interact through both hydrodynamic and non-hydrodynamic forces, where the latter may be any type of Brownian. colloidal, interparticle or external force. The method is also readily extended to dynamically simulate both unbounded and bounded suspensions.