250 research outputs found
Toward a typeface for the transcription of facial actions in sign languages
International audienceNon-manual actions, and more specifically facial actions (FA) can be found in all Sign Languages (SL). Those actions involve all the different facial parts and can have various and intricate linguistic relations with manual signs. Unlike in vocal languages, FA in SL provide more meaning than simple expressions of feelings and emotions. Yet non-manual parameters are among the most unknown formal features in SL studies. During the past 30 years, some studies have started questioning the meanings and linguistic values and the relations between manual and non-manual signs (Crashborn et al. 2008; Crashborn & Bank 2014); more recently, SL corpora have been analysed, segmented, and transcribed to help study FA (Vogst-Svenden 2008; Bergman et al. 2008; Sutton-Spence & Day 2008).Moreover, to fill the lack of an annotation system for FA, a few manual annotation systems have integrated facial glyphs, such as HamNoSys (Prillwitz et al. 1989) and SignWriting (Sutton 1995). On one hand, HamNoSys has been developed to describe all existing SLs at a phonetic level; it allows a formal, linear, highly detailed and searchable description of manual parameters. As for non-manual parameters, HamNoSys offers the replacement of hands by another articulators. Non-manual parameters can be written as “eyes” or “mouth” and described by the same symbols developed for hands (Hanke 2004). Unfortunately only a limited number of manual symbols can be translated into FA and the annotation system remains incomplete. On the other hand, SignWriting describes SL with iconic symbols placed in a 2D space representing the signer’s body. Facial expressions are divided into mouth, eyes, nose, eyebrows, etc., and are drawn in a circular “head” much like emoticons. SignWriting offers a detailed description of posture and actions of non-manual parameters, but does not ensure compatibility with the most common annotation software used by SL linguists (e.g., ELAN).Typannot, a interdisciplinary project led by linguists, designers, and developers, which aims to set up a complete transcription system for SL that includes every SL parameter (handshape, localisation, movement, FA), has developed a different methodologie. As mentioned earlier, FA have various linguistic values (mouthings, adverbial mouth gestures, semantically empty, enacting, whole face) and also include prosody and emotional meanings. In this regard, they can be more variable and signer-related than manual parameters. To offer the best annotation tool, Typannot’s approach has been to define facial parameters and all their possible tangible configurations. The goal is to set up the most efficient, simple, yet complete and universal formula to describe all possible FA.This formula is based on a 3 dimensional grid. Indeed all the different configurations of FA can be described by its X, Y, Z axis position. As a result, all FA can be described and encoded using a restricted list of 39 qualifiers. Based on this model and to help reduce the annotation process, a set of generic glyphs has been developed. Each qualifier has its own symbolic “generic” glyph. This methodical decomposition of all facial components enables a precise and accurate transcription of a complex FA using only a few glyphs.This formula and its generic glyphs have gone through a series of tests and revisions. Recently, an 18m20s long FA corpus of two deaf signers has been recorded using two different cameras. The first one, RGB HQ, is used to capture a high quality image and the second, infrared Kinect, is used to captured the depth. The latter was linked with Brekel Proface 2 (Leong et al. 2015), a 3D animation software that enables an automatic recognition of FA. This corpus has been fully annotated using Typannot’s generic glyphs. These annotations have enabled the validation of the general structure of Typannot FAformula and to identify some minor corrections to be made. For instance, it has been shown that the description of the air used to puff out or suck in cheeks is too restrictive and the description of the opening and closure of the eyelids is too unnecessarily precise.When those changes are implemented, our next task will be to develop a morphological glyphic system that will combine the different generic glyphs used for each facial parameter into one unique morphological glyph. This means that for any given FA, all the information contained in Typannot descriptive formula will be contained within one legible glyph. Some early research and work has already begun on this topic, but needs further development before providing a statement on its typographic structure. When this system is completed, it will be released with its own virtual keyboard (Typannot Keyboard, currently in development for handshapes) to help transcription and improve annotation processes.Bibliography :-Chételat-Pelé, E. (2010). Les Gestes Non Manuels en Langue des Signes Française ; Annotation, analyse et formalisation : application aux mouvements des sourcils et aux clignements des yeux. Université de Provence - Aix-Marseille I.-Crasborn, O., Van Der Kooij, E., Waters, D., Woll, B., & Mesch, J. (2008). Frequency distribution and spreading behavior of different types of mouth actions in three sign languages. Sign Language & Linguistics, 11(1), 45–67.-Crasborn, O. A., & Bank, R. (2014). An annotation scheme for the linguistic study of mouth actions in sign languages. http://repository.ubn.ru.nl/handle/2066/132960-Fontana, S. (2008). Mouth actions as gesture in sign language. Gesture, 8(1), 104‑123.-Hanke, T. (2004). HamNoSys—Representing sign language data in language resources and language processing contexts. In Workshop on the Representation and Processing of Sign Languages on the occasion of the Fourth International Conference on Language Resources and Evaluation (p. 1‑6).-Leong, C. W., Chen, L., Feng, G., Lee, C. M., & Mulholland, M. (2015). Utilizing depth sensors for analyzing multimodal presentations: Hardware, software and toolkits (p. 547‑556).Presented at Proceedings of the 2015 ACM on International Conference on Multimodal Interaction, ACM.-Prillwitz, S., Leven, R., Zienert, H., Hanke, T., & Henning, J. (1989). Hamburg notation system for sign languages: An introductory guide. Signum Press, Hamburg.-Sandler, W. (2009). Symbiotic symbolization by hand and mouth in sign language. Semiotica, 2009(174), 241‑275. http://doi.org/10.1515/semi.2009.035-Sutton, V. (1995). Lessons in Sign Writing: Textbook. DAC, La Jolla (CA).-Sutton-Spence, R., & Boyes-Braem, P. (2001). The hands are the head of the mouth: The mouth as articulator in sign languages. Signum Press, Hamburg
IMPACT OF COVID-19 ON PEOPLE LIVING WITH HIV IN MADAGASCAR: A SARS-COV2 SERO-PREVALENCE SURVEY
Background: In Madagascar, no study has reported the impact of COVID-19 on people living with HIV (PLHIV). The present work aimed to analyze the seroprevalence of SARS-CoV-2 in Malagasy PLHIV before and during the three waves of COVID-19 pandemic.This is a retrospective study.
Materials and Methods: We conducted a retrospective serological survey in PLHIV followed up for HIV viral load (VL) monitoring at the Centre d’Infectiologie Charles Mérieux Madagascar (CICM) between June 2019 and April 2022. The presence of IgM and/or IgG antibodies against SARS-CoV-2 nucleoprotein was detected using a rapid diagnostic test (COVID-PRESTO®).
Results: A seroprevalence of 2.5% was found in the 877 patients tested before March 2020, compared to 25.4% (512/2,011) between March 2020 and April 2022. This seroprevalence was 21.7%, 22.3% and 60.1% after the first, second and third waves of COVID-19, respectively. We observed a marginally significant difference (p = 0.043) in SARS-CoV-2 seroprevalence between patients on highly active antiretroviral therapy (HAART) (27.5%) and those who were not (23.7%). No statistically significant difference was observed between PLHIV with undetectable HIV VL (27.4%) and the different detectable VL categories (p>0.05).
Conclusions: Our data show the presence of antibodies to SARS-CoV-2 among PLHIV as early as December 2019 in Madagascar. At least 25.4% (512/2,011) of Malagasy PLHIV have been in contact with SARS-CoV-2 since March 2020. There is no significant relation between HIV-1 VL and SARS-CoV-2 seroprevalence. Additional studies with more robust assays in the general population are needed for a detailed knowledge of SARS-CoV-2 impact in Madagascar
Avian influenza vaccination of poultry and passive case reporting, Egypt
We investigated the infl uence of a mass poultry vaccination campaign on passive surveillance of highly pathogenic avian infl uenza subtype (H5N1) outbreaks among poultry in Egypt. Passive reporting dropped during the campaign, although probability of infection remained unchanged. Future poultry vaccination campaigns should consider this negative impact on reporting for adapting surveillance strategies. (Résumé d'auteur
Vezatin is essential for dendritic spine morphogenesis and functional synaptic maturation.
International audienceVezatin is an integral membrane protein associated with cell-cell adhesion complex and actin cytoskeleton. It is expressed in the developing and mature mammalian brain, but its neuronal function is unknown. Here, we show that Vezatin localizes in spines in mature mouse hippocampal neurons and codistributes with PSD95, a major scaffolding protein of the excitatory postsynaptic density. Forebrain-specific conditional ablation of Vezatin induced anxiety-like behavior and impaired cued fear-conditioning memory response. Vezatin knock-down in cultured hippocampal neurons and Vezatin conditional knock-out in mice led to a significantly increased proportion of stubby spines and a reduced proportion of mature dendritic spines. PSD95 remained tethered to presynaptic terminals in Vezatin-deficient hippocampal neurons, suggesting that the reduced expression of Vezatin does not compromise the maintenance of synaptic connections. Accordingly, neither the amplitude nor the frequency of miniature EPSCs was affected in Vezatin-deficient hippocampal neurons. However, the AMPA/NMDA ratio of evoked EPSCs was reduced, suggesting impaired functional maturation of excitatory synapses. These results suggest a role of Vezatin in dendritic spine morphogenesis and functional synaptic maturation
Age-dependent effects of chronic fluoxetine treatment on the serotonergic system one week following treatment
Abstract Rationale Selective serotonin reuptake inhibitors (SSRIs) such as fluoxetine are increasingly used for the treatment of depression in children. Limited data are, however, available on their effects on brain development and their efficacy remains debated. Moreover, previous experimental studies are seriously hampered in their clinical relevance. Objectives The aim of the present study was to investigate putative age-related effects of a chronic treatment with fluoxetine (5 mg/kg, either orally or i.p. for 3 weeks, 1 week washout) using conventional methods (behavioral testing and binding assay using [ 123 I]β-CIT) and a novel magnetic resonance imaging (MRI) approach. Methods Behavior was assessed, as well as serotonin transporter (SERT) availability and function through ex vivo binding assays and in vivo pharmacological MRI (phMRI) with an acute fluoxetine challenge (10 mg/kg oral or 5 mg/kg i.v.) in adolescent and adult rats. Results Fluoxetine caused an increase in anxiety-like behavior in treated adult, but not adolescent, rats. On the binding assays, we observed increased SERT densities in most cortical brain regions and hypothalamus in adolescent, but not adult, treated rats. Finally, reductions in brain activation were observed with phMRI following treatment, in both adult and adolescent treated animals. Conclusion Collectively, our data indicate that the shortterm effects of fluoxetine on the 5-HT system may be agedependent. These findings could reflect structural and functional rearrangements in the developing brain that do not occur in the matured rat brain. phMRI possibly will be well suited to study this important issue in the pediatric population
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