Concevoir des interfaces tangibles et spatiales pour les déficients visuels : pourquoi et comment ?

International audienceMaking geographical maps and graphical representations accessible to visually impaired users is essential. To do so, a variety of approaches exist, whether traditional or technological. Among them, tangible interfaces, although very promising, have not been thoroughly investigated. In this article, we analyze five research prototypes in order to identify the aspects that have to be taken into account when designing spatial tangible interfaces for visually impaired users, and we present the various solutions that have been proposed to address the most commonly encountered problems. In this way we hope to facilitate and support the development and evaluation of spatial tangible interfaces.Rendre les cartes géographiques et les représentations graphiques accessibles aux personnes déficientes visuelles est primordial. Pour cela, de nombreuses solutions existent, qu’elles soient artisanales ou technologiques. Parmi ces dernières, les interfaces tangibles, bien que très prometteuses, ont été très peu étudiées. Dans cet article, nous analysons cinq prototypes issus de la littérature afin d’identifier les facteurs à prendre en compte lors de la conception d’interfaces tangibles et spatiales pour les déficients visuels, et nous présentons les solutions proposées pour répondre aux difficultés techniques fréquemment rencontrées. Nous souhaitons ainsi faciliter et encourager le développement et l’évaluation d’interfaces tangibles et spatiales

Techniques d'interactions sur dispositifs mobiles pour l'aide à l'orientation chez les non-voyants

National audienceLes aides électroniques à la navigation commencent à se diffuser auprès des personnes déficientes visuelles. Elles ont cependant l'inconvénient de ne fournir que des informations sur la destination à atteindre et sur l'itinéraire à suivre, et non sur les éléments présents autour de l'utilisateur tout au long du parcours. Ces dispositifs ne permettent pas aux non-voyants de construire une carte mentale de leur environnement, ce qui est pourtant très utile pour mieux comprendre un déplacement et l'environnement dans lequel il s'est déroulé. Les techniques non-visuelles d'assistance à l'orientation développées sur téléphone mobile dans le cadre de cette étude visent à fournir ces indications manquantes. Elles ont pour objectif de permettre à un utilisateur de localiser trois points de repère prédéfinis, situés dans l'environnement proche (quelques dizaines à centaines de mètres) : à partir de ces informations, l'utilisateur peut déterminer sa position. Trois techniques de présentation de points de repère ont été conçues et développées. Des évaluations préliminaires ont permis de montrer que la connaissance des distances et directions de ces trois points permet à un utilisateur non-voyant, ayant au préalable appris une carte de l'environnement correspondant, de se situer, de s'orienter et d'atteindre une destination dans un environnement ouvert

Les technologies d'assistance pour la qualité de vie et l'autonomie des déficients visuels (TAVIS)

International audienceLe nombre de personnes déficientes visuelles est évalué à 285 millions dans le monde. L'analyse des limitations d'activité et restrictions de participation de ces personnes montre que les nouvelles technologies interactives peuvent apporter des réponses pertinentes pour améliorer leur autonomie. Depuis une décennie, nous avons lancé un ensemble de recherches fondamentales et appliquées permettant de concevoir des dispositifs d'assistance pour les déficients visuels. Les différents domaines concernés sont l'orientation et la mobilité, l'accessibilité des documents (cartes géographiques), l'accessibilité des dispositifs mobiles (smartphones ou tablettes) ou la simulation de la vision prothétique (implant rétinien ou cortical). Afin de travailler de façon pérenne sur la conception de nouvelles technologies d'assistance avec les déficients visuels mais aussi les formateurs et enseignants spécialisés, nous avons créé un laboratoire de recherche commun avec un Centre d'Education Spécialisé pour Déficients Visuel

Damage function for historic paper. Part II: Wear and tear

Background: As a result of use of library and archival documents, defined as reading with handling in the context of general access, mechanical degradation (wear and tear) accumulates. In contrast to chemical degradation of paper, the accumulation of wear and tear is less well studied. Previous work explored the threshold of mechanical degradation at which a paper document is no longer considered to be fit for the purpose of use by a reader, while in this paper we explore the rate of accumulation of such damage in the context of object handling. Results: The degree of polymerisation (DP) of historic paper of European origin from mid-19th–mid-20th Century was shown to affect the rate of accumulation of wear and tear. While at DP > 800, this accumulation no longer depends on the number of handlings (the process is random), a wear-out function could be developed for documents with DP between 300 and 800. For objects with DP < 300, one large missing piece (i.e. such that contains text) developed on average with each instance of handling, which is why we propose this DP value as a threshold value for safe handling. Conclusions: The developed model of accumulation of large missing pieces per number of handlings of a document depending on DP, enables us to calculate the time required for an object to become unfit for use by readers in the context of general access. In the context of the average frequency of document use at The UK National Archives (Kew), this period is 60 years for the category of papers with DP 300, and 450 years for papers with DP 500. At higher DP values, this period of time increases beyond the long-term planning horizon of 500 years, leading to the conclusion that for such papers, accumulation of wear and tear is not a significant collection management concern

Looking beneath Dali's paint: non-destructive canvas analysis

A new analytical method was developed to non-destructively determine pH and degree of polymerisation (DP) of cellulose in fibres in 19th–20th century painting canvases, and to identify the fibre type: cotton, linen, hemp, ramie or jute. The method is based on NIR spectroscopy and multivariate data analysis, while for calibration and validation a reference collection of 199 historical canvas samples was used. The reference collection was analysed destructively using microscopy and chemical analytical methods. Partial least squares regression was used to build quantitative methods to determine pH and DP, and linear discriminant analysis was used to determine the fibre type. To interpret the obtained chemical information, an expert assessment panel developed a categorisation system to discriminate between canvases that may not be fit to withstand excessive mechanical stress, e.g. transportation. The limiting DP for this category was found to be 600. With the new method and categorisation system, canvases of 12 Dalí paintings from the Fundació Gala-Salvador Dalí (Figueres, Spain) were non-destructively analysed for pH, DP and fibre type, and their fitness determined, which informs conservation recommendations. The study demonstrates that collection-wide canvas condition surveys can be performed efficiently and non-destructively, which could significantly improve collection management

The development of parental monitoring during adolescence : A meta-analysis

As adolescents grow up, one of the important developmental tasks is to individuate themselves and to become more autonomous from parents. This requires a realignment of the parent-adolescent communication. The current meta-analytic study aims at identifying developmental changes in parent-adolescent communication, conceptualized within the parental monitoring framework, as entailing parental solicitation, control and knowledge, and adolescent’s disclosure and secrecy. Thirty-one longitudinal studies published between 2000 and 2015 were identified and included in the current meta-analysis. Informants, age at assessment and study duration were tested as moderators. Results showed a low to medium normative decline in parental control (Cohen’s d = −.395, 95% CI [−.541, −.249]), knowledge (d = −.245,95% CI [−.331, −.160] and adolescence disclosure (d = −.147, 95% CI [−.204, −.090]), and an increase in adolescent’s secrecy (d = .194, CI [031, .356]). Parental solicitation decreased based on parents’ (d = −.242, 95% CI[−.376, −.109]) but not on adolescents’ reports (d = .038, 95% CI[−.099, .175]). Another significant moderator was the duration of the study, with studies longer than 2 years being able to detect a more pronounced change in parental control than studies lasting less than 2 years (≤2 years, d = −.139 vs. duration > 2 years, d = −.581). Limitations of the current knowledge and new directions of studies are discussed.Peer reviewe

On the potential of using Nanocellulose for consolidation of painting canvases

Nanocellulose has been recently proposed as a novel consolidant for historical papers. Its use for painting canvas consolidation, however, remains unexplored. Here, we show for the first time how different nanocelluloses, namely mechanically isolated cellulose nanofibrils (CNF), carboxymethylated cellulose nanofibrils (CCNF) and cellulose nanocrystals (CNC), act as a bio-based alternative to synthetic resins and other conventional canvas consolidants. Importantly, we demonstrate that compared to some traditional consolidants, all tested nanocelluloses provided reinforcement in the adequate elongation regime. CCNF showed the best consolidation per added weight; however, it had to be handled at very low solids content compared to other nanocelluloses, exposing canvases to larger water volumes. CNC reinforced the least per added weight but could be used in more concentrated suspensions, giving the strongest consolidation after an equivalent number of coatings. CNF performed between CNC and CCNF. All nanocelluloses showed better consolidation than lining with synthetic adhesive (Beva 371) and linen canvas in the elongation region of interest

Active wetting of epithelial tissues

Development, regeneration and cancer involve drastic transitions in tissue morphology. In analogy with the behavior of inert fluids, some of these transitions have been interpreted as wetting transitions. The validity and scope of this analogy are unclear, however, because the active cellular forces that drive tissue wetting have been neither measured nor theoretically accounted for. Here we show that the transition between 2D epithelial monolayers and 3D spheroidal aggregates can be understood as an active wetting transition whose physics differs fundamentally from that of passive wetting phenomena. By combining an active polar fluid model with measurements of physical forces as a function of tissue size, contractility, cell-cell and cell-substrate adhesion, and substrate stiffness, we show that the wetting transition results from the competition between traction forces and contractile intercellular stresses. This competition defines a new intrinsic lengthscale that gives rise to a critical size for the wetting transition in tissues, a striking feature that has no counterpart in classical wetting. Finally, we show that active shape fluctuations are dynamically amplified during tissue dewetting. Overall, we conclude that tissue spreading constitutes a prominent example of active wetting --- a novel physical scenario that may explain morphological transitions during tissue morphogenesis and tumor progression

Interactivity Improves Usability of Geographic Maps for Visually Impaired People

International audienceTactile relief maps are used by visually impaired people to acquire mental representation of space, but they retain important limitations (limited amount of information, braille text, etc.). Interactive maps may overcome these limitations. However, usability of these two types of maps had never been compared. It is then unknown whether interactive maps are equivalent or even better solutions than traditional raised-line maps. This study presents a comparison of usability of a classical raised-line map vs. an interactive map composed by a multi-touch screen, a raised-line overlay and audio output. Both maps were tested by 24 blind participants. We measured usability as efficiency, effectiveness and satisfaction. Our results show that replacing braille with simple audio-tactile interaction significantly improved efficiency and user satisfaction. Effectiveness was not related to the map type but depended on users' characteristics as well as the category of assessed spatial knowledge. Long-term evaluation of acquired spatial information revealed that maps, whether interactive or not, are useful to build robust survey-type mental representations in blind users. Altogether, these results are encouraging as they show that interactive maps are a good solution for improving map exploration and cognitive mapping in visually impaired people

Prospective randomized trial of iliohypogastric-ilioinguinal nerve block on post-operative morphine use after inpatient surgery of the female reproductive tract

<p>Abstract</p> <p>Objective</p> <p>To determine the impact of pre-operative and intra-operative ilioinguinal and iliohypogastric nerve block on post-operative analgesic utilization and length of stay (LOS).</p> <p>Methods</p> <p>We conducted a prospective randomized double-blind placebo controlled trial to assess effectiveness of ilioinguinal-iliohypogastric nerve block (IINB) on post-operative morphine consumption in female study patients (<it>n </it>= 60). Patients undergoing laparotomy via Pfannenstiel incision received injection of either 0.5% bupivacaine + 5 mcg/ml epinephrine for IINB (Group I, <it>n </it>= 28) or saline of equivalent volume given to the same site (Group II, <it>n </it>= 32). All injections were placed before the skin incision and after closure of rectus fascia via direct infiltration. Measured outcomes were post-operative morphine consumption (and associated side-effects), visual analogue pain scores, and hospital length of stay (LOS).</p> <p>Results</p> <p>No difference in morphine use was observed between the two groups (47.3 mg in Group I vs. 45.9 mg in Group II; <it>p </it>= 0.85). There was a trend toward lower pain scores after surgery in Group I, but this was not statistically significant. The mean time to initiate oral narcotics was also similar, 23.3 h in Group I and 22.8 h in Group II (<it>p </it>= 0.7). LOS was somewhat shorter in Group I compared to Group II, but this difference was not statistically significant (<it>p </it>= 0.8). Side-effects occurred with similar frequency in both study groups.</p> <p>Conclusion</p> <p>In this population of patients undergoing inpatient surgery of the female reproductive tract, utilization of post-operative narcotics was not significantly influenced by IINB. Pain scores and LOS were also apparently unaffected by IINB, indicating a need for additional properly controlled prospective studies to identify alternative methods to optimize post-surgical pain management and reduce LOS.</p