Associating Vehicles Automation With Drivers Functional State Assessment Systems: A Challenge for Road Safety in the Future

In the near future, vehicles will gradually gain more autonomous functionalities. Drivers’ activity will be less about driving than about monitoring intelligent systems to which driving action will be delegated. Road safety, therefore, remains dependent on the human factor and we should identify the limits beyond which driver’s functional state (DFS) may no longer be able to ensure safety. Depending on the level of automation, estimating the DFS may have different targets, e.g., assessing driver’s situation awareness in lower levels of automation and his ability to respond to emerging hazard or assessing driver’s ability to monitor the vehicle performing operational tasks in higher levels of automation. Unfitted DFS (e.g., drowsiness) may impact the driver ability respond to taking over abilities. This paper reviews the most appropriate psychophysiological indices in naturalistic driving while considering the DFS through exogenous sensors, providing the more efficient trade-off between reliability and intrusiveness. The DFS also originates from kinematic data of the vehicle, thus providing information that indirectly relates to drivers behavior. The whole data should be synchronously processed, providing a diagnosis on the DFS, and bringing it to the attention of the decision maker in real time. Next, making the information available can be permanent or intermittent (or even undelivered), and may also depend on the automation level. Such interface can include recommendations for decision support or simply give neutral instruction. Mapping of relevant psychophysiological and behavioral indicators for DFS will enable practitioners and researchers provide reliable estimates, fitted to the level of automation

Effects of Age and Task Load on Drivers’ Response Accuracy and Reaction Time When Responding to Traffic Lights

International audienceDue to population aging, elderly drivers represent an increasing proportion of car drivers. Yet, how aging alters sensorimotor functions and impacts driving safety remains poorly understood. This paper aimed at assessing to which extent elderly drivers are sensitive to various task loads and how this affects the reaction time (RT) in a driving context. Old and middle-aged people completed RT tasks which reproduced cognitive demands encountered while driving. Participants had to detect and respond to traffic lights or traffic light arrows as quickly as possible, under three experimental conditions of incremental difficulty. In both groups, we hypothesized that decision-making would be impacted by the number of cues to be processed. The first test was a simple measure of RT. The second and third tests were choice RT tasks requiring the processing of 3 and 5 cues, respectively. Responses were collected within a 2 s time-window. Otherwise, the trial was considered a no-response. In both groups, the data revealed that RT, error rate (incorrect answers), and no-response rate increased along with task difficulty. However, the middle-aged group outperformed the elderly group. The RT difference between the two groups increased drastically along with task difficulty. In the third test, the rate of no-response suggested that elderly drivers needed more than 2 s to process complex information and respond accurately. Both prolonged RT and increased no-response rate, especially for difficult tasks, might attest an impairment of cognitive abilities in relation to aging. Accordingly, casual driving conditions for young drivers may be particularly complex and stressful for elderly people who should thus be informed about the effects of normal aging upon driving

Sur la réponse transitoire d'une structure en alliage à mémoire de forme soumise à un impact

National audienceDans cet article sont présentées des évolutions du modèle RL nécessaires pour la résolution de problèmes de dynamique rapide. Le modèle initial, basé sur le comportement thermomécanique de l'alliage couplé à l'équation de la chaleur, a été implémenté dans le cadre de la dynamique basses fréquences dans des travaux antérieurs. L'utilisation de ce modèle non linéaire dans le cadre de la dynamique rapide (réponse de la structure à un impact) conduit à des solutions non physiques ou à des divergences des algorithmes d'intégration temporelle. Ces comportements sont principalement dus aux fortes non-linéarités des équations régissant les cinétiques de transformation entre les deux phases du matériau (austénite/martensite). L'adjonction d'un terme lissant dans les équations différentielles permet de faire converger les algorithmes sans perturber le comportement du modèle initial. Ce terme, d'un point de vue physique, traduit le fait que la transformation de phase ne se fait pas de façon instantanée, mais à une vitesse de propagation donnée. Les résultats issus d'un calcul éléments finis considérant une structure bidimensionnelle soumise à un impact sont présentés

Symbolic dynamics techniques for complex systems: Application to share price dynamics

The symbolic dynamics technique is well known for low-dimensional dynamical systems and chaotic maps, and lies at the roots of the thermodynamic formalism of dynamical systems. Here we show that this technique can also be successfully applied to time series generated by complex systems of much higher dimensionality. Our main example is the investigation of share price returns in a coarse-grained way. A nontrivial spectrum of Rényi entropies is found. We study how the spectrum depends on the time scale of returns, the sector of stocks considered, as well as the number of symbols used for the symbolic description. Overall our analysis confirms that in the symbol space transition probabilities of observed share price returns depend on the entire history of previous symbols, thus emphasizing the need for a modelling based on non-Markovian stochastic processes. Our method allows for quantitative comparisons of entirely different complex systems, for example the statistics of symbol sequences generated by share price returns using 4 symbols can be compared with that of genomic sequences

Whole exome sequencing reveals pathogenic variants in MYO3A, MYO15A and COL9A3 and differential frequencies in ancestral alleles in hearing impairment genes among individuals from Cameroon

There is scarcity of known gene variants of hearing impairment (HI) in African populations. This knowledge deficit is ultimately affecting the development of genetic diagnoses. We used whole exome sequencing to investigate gene variants, pathways of interactive genes and the fractions of ancestral overderived alleles for 159 HI genes among 18 Cameroonian patients with non-syndromic HI (NSHI) and 129 ethnically matched controls. Pathogenic and likely pathogenic (PLP) variants were found in MYO3A, MYO15A and COL9A3, with a resolution rate of 50% (9/18 patients). The study identified significant genetic differentiation in novel population-specific gene variants at FOXD4L2, DHRS2L6, RPL3L and VTN between HI patients and controls. These gene variants are found in functional/co-expressed interactive networks with other known HI-associated genes and in the same pathways with VTN being a hub protein, that is, focal adhesion pathway and regulation of the actin cytoskeleton (P-values <0.05). The results suggest that these novel population-specific gene variants are possible modifiers of the HI phenotypes. We found a high proportion of ancestral allele versus derived at low HI patients-specific minor allele frequency in the range of 0.0–0.1. The results showed a relatively low pickup rate of PLP variants in known genes in this group of Cameroonian patients with NSHI. In addition, findings may signal an evolutionary enrichment of some variants of HI genes in patients, as the result of polygenic adaptation, and suggest the possibility of multigenic influence on the phenotype of congenital HI, which deserves further investigations

Hepatogenous photosensitisation in cows grazing turnips (Brassica rapa) in South Africa

Holstein cows on a farm in the Humansdorp district, Eastern Cape province, South Africa, developed reddened, painful teat skin 3 days after grazing a mixed forage crop dominated by bulb turnip (Brassica rapa, Barkant cultivar). The crop was grazed 45 days after planting and 10% of the herd developed symptoms. More characteristic non-pigmented skin lesions started manifesting 1–2 days after the appearance of the teat lesions. Affected cows had elevated serum activities of gamma-glutamyl transferase, glutamate dehydrogenase and aspartate aminotransferase. These blood chemistry findings confirmed a secondary (hepatogenous) photosensitivity. As a result of the severity of the teat and skin lesions, seven cows were slaughtered and tissue samples from five of them were collected for histopathological examination. Liver lesions in cows that were culled 3 or more weeks after the onset of the outbreak showed oedematous concentric fibrosis around medium-sized bile ducts and inflammatory infiltrates in portal tracts. Characteristic lesions associated with other known hepatobiliary toxicities were not found. No new cases were reported 5 days after the cattle were removed from the turnips. The sudden introduction of the cows, without any period of transitioning or adaptation to grazing turnips, as well as the short latent period, clinical signs of photosensitisation, blood chemistry and histopathology, confirmed a diagnosis of Brassicaassociated liver disease, a condition seen in New Zealand but not previously described in South Africa. Brassica forage crops are potentially toxic under certain conditions and farmers must be aware of these risks.http://www.jsava.co.zaam2022Paraclinical Science

Measuring motor imagery using psychometric, behavioural, and psychophysiological tools

Measuring motor imagery using psychometric, behavioral, and psychophysiological tools. Exerc. Sport Sci. Rev., Vol. 39, No. 2, pp. 85Y92, 2011. This review examines the measurement of motor imagery (MI) processes. First, self-report measures of MI are evaluated. Next, mental chronometry measures are considered. Then, we explain how physiological indices of the autonomic nervous system can measure MI. Finally, we show how these indices may be combined to produce a measure of MI quality called the Motor Imagery Index. Key Words: motor imagery, mental imagery, psychometric measures, mental chronometry, autonomic nervous system, electrodermal and cardiac activities. MOTOR IMAGERY Motor imagery (MI), or the mental simulation of motor movement, is the cognitive rehearsal of an action without actually executing it (9,26). As the mental representation of a movement without the concomitant production of the muscle activity necessary for its implementation, MI has attracted increasing interest from researchers in sport science, psychology, and cognitive neuroscience During the past 15 years or so, we have conducted a number of studies on theoretical, practical, and rehabilitation issues involving MI. First, we have investigated the brain mechanisms underlying motor skill rehearsal and movement planning (11). Second, we have shown with others that the MI technique of mental practice (&apos;&apos;seeing&apos;&apos; and &apos;&apos;feeling&apos;&apos; a movement in one&apos;s imagination before executing it) can increase physical strength performance (30) and enhance skill learning (3) and technical performance in athletes (4,32). Finally, we confirmed that MI training can facilitate rehabilitation from physical injury or neurological damage ((5) see (22) for a review). Elsewhere, we have provided a detailed account of research findings on MI (12). Considering that MI is a multidimensional construct (see model developed by Guillot and Collet (10)), we have measured its underlying processes using a combination of psychometric tests (18), qualitative procedures (19,25), chronometric methods in which MI processes are investigated by comparing the duration required to execute real and imagined actions (8), and psychophysiological techniques (1). Although these approaches have each yielded some interesting results (12), they have not yet been combined adequately to provide an aggregate index of MI quality. Therefore, the purpose of this review is to propose a rationale for our novel hypothesis that it is possible to calculate an index of MI quality by quantitatively combining psychometric, qualitative, chronometric, and psychophysiological measures. Our proposed Motor Imagery Index (MII) has significant implications for researchers and practitioners because it can be used to understand individual differences in MI and to assess the efficacy of MI interventions. PSYCHOMETRIC APPROACH For more than a century, researchers have used standardized self-report questionnaires to measure individual differences in imagery dimensions such as vividness (i.e., the clarity or sensory richness of an image) and controllability (i.e., the ease and accuracy with which an image can be manipulated mentally, see (24)). We have investigated both of these dimensions of imagery in sport settings. For example, we found that elite canoe-slalom competitors reported significantly greater use of MI than did less proficient counterparts when preparing for races (17). We investigated the effects of MI on the learning (through both physical and mental practice) of volleyball technique among intermediate performers of this sport (32). We found that a combination of MI and physical practice produced the most efficien

Multilevel Contracts for Trusted Components

This article contributes to the design and the verification of trusted components and services. The contracts are declined at several levels to cover then different facets, such as component consistency, compatibility or correctness. The article introduces multilevel contracts and a design+verification process for handling and analysing these contracts in component models. The approach is implemented with the COSTO platform that supports the Kmelia component model. A case study illustrates the overall approach.Comment: In Proceedings WCSI 2010, arXiv:1010.233