34 research outputs found

    LES FACTEURS DÉTERMINANTS DE L’INTENTION D'ACHAT EN LIGNE EN TUNISIE

    Get PDF
    Ce travail a pour objectif d'analyser les facteurs qui influent sur le comportement d'achat en ligne des consommateurs tunisiens et qui pourraient être l'un des plus importants enjeux du commerce électronique et du marketing. Pour réaliser cet objectif, nous nous sommes basées sur un modèle examinant l'impact des risques perçus, l’utilité attendue, l’expérience d’achat et la confiance envers les boutiques en ligne sur l’attitude envers l'achat en ligne ; et la relation entre cette attitude et l’intention de commander par Internet. Partant d’une riche revue de littérature, nous avons fixés 7 hypothèses de recherche dans le but d’examiner le lien entre l’intention d’achat en ligne et les facteurs explicatifs. Une étude quantitative a été menée auprès d’un échantillon de 350 personnes pour esquisser les questions de recherche soulevée

    The influence of cognitive load and vision variability on postural balance in adolescents with intellectual disabilities

    Get PDF
    IntroductionThis study aimed to investigate the impact of cognitive load, particularly its escalation during the execution of the same test, under varying vision conditions, on postural balance among adolescents with intellectual disability (ID).MethodsTwenty adolescents underwent balance assessments under different visual conditions (Open Eyes (OE), Closed Eyes (CE), Flash, Goggles, Visual Stimulation (VS)) and task settings (Single Task (ST), Dual Task (DT) without challenges, and DT with challenges). The cognitive test was assessed using Verbal Fluency (VF).Results and discussionSignificant effects were found for Task (p < 0.001, ηp2 = 0.85), indicating that CoP values significantly increased (p < 0.05) with the introduction of the DT. Dual Task Cost (DTC) demonstrated significant effects for Vision (p = 0.008, ηp2 = 0.62), with values varying significantly (p < 0.05) among different vision conditions, especially in CE and Flash conditions. Visual Dependency Quotient (VDQ) analyses revealed significant effects of condition (p < 0.001, ηp2 = 0.84), with significant changes observed in CE/OE and Flash/OE conditions (p < 0.05). Significant effects were observed for Cognitive performance in the Challenge condition (p < 0.001, ηp2 = 0.86), with decreased performance with cognitive task challenges, particularly in Flash and Goggles conditions (p < 0.05). In conclusion, cognitive tasks, especially challenging ones, and visual variations significantly impact postural balance in adolescents with ID

    Assessment of the validity of self-reported smoking status among schoolchildren in Sousse, Tunisia

    Get PDF
    Introduction: Tobacco use, which begins in adolescence and childhood and continues in later life, is the major avoidable risk for non-communicable diseases and death in the world. Self-reports have frequently been used to estimate smoking prevalence and health consequences. This study explores the validity of self-reports of smoking behavior among schoolchildren in Tunisia. Materials and methods: This study was conducted in March 2014 among a sample of 147 schoolchildren randomly selected. Data concerning the smoking habit were collected by a questionnaire designed for the purposes of this work. Then, exhaled CO, a biochemical marker of smoke exposure, was measured using piCO+ Smokerlyzer® breath CO monitor among participants. Sensitivity and specificity of self-reports were calculated. Results: The prevalence of reported smoking was 9.5% with 16.7% and 1.7% respectively among boys and girls. Their mean age was 14.5±1.28 years old. When considering 4 ppm as the cut-off level of breath CO, sensitivity and specificity of self-reports were 100% and 93.7%, respectively. But at a breath CO cut-off of 3 ppm, self-reporting was 62.5% sensitive and 93.5% specific. Conclusion: According to our findings, we suggest that self-reports can be considered as a good tool to be used with a reasonable confidence to assess the smoking status

    Détermination des efforts articulaires induits par le mouvement de 1/2 squat avec charge additionnelle (approche cinématique et cinétique)

    No full text
    CLERMONT FD-BCIU Sci.et Tech. (630142101) / SudocCLERMONT FD-UBP-UFR STAPS (630142215) / SudocSudocFranceF

    Hybrid Program Based on Virtual and Real Games Increases Fundamental Movement Skills in Children With Intellectual Disability: A Quasi-Experimental Study

    No full text
    International audienceThe purpose of this study was to examine the effects of two pedagogical strategies in adapted physical education (hybrid virtual/real vs. conventional) on fundamental movement skills (FMS) in children with intellectual disability age 7–10 years. Children with intellectual disability ( N = 24) were randomly assigned to either the hybrid (experimental group) or the conventional (control group) group and were evaluated across 10 weeks. The hybrid program was based on virtual and real game situations, while the conventional program was based on adapted sports. FMS were evaluated using the Test of Gross Motor Development-2 at pre- and postprogram for both groups. Both programs significantly improve locomotor skills, with significantly better improvement in the experimental group. However, a significant improvement was observed only among the experimental group for object-control skills and gross motor quotient. Based on these results, a hybrid program may be considered for FMS improvement

    Use of nurse endosperm for the culture of haploid embryos produced by durum wheat x maize crosses

    No full text
    The use of doubled-haploids in plant breeding programs enables accelerating the release of new varieties adapted to climate change. The durum wheat x maize crosses technique is a method of choice for producing durum wheat haploid plants. The haploid embryos produced by this method develop without albumen and their survival is ensured by post-pollination hormonal treatments. In this study, nine post-pollination treatments with 2,4-Dichlorophenoxyacetic acid (2,4-D), Picloram and Dicamba at the concentrations of 10, 50 and 100 mg.L-1 were applied to 7 durum wheat genotypes. The effects of genotype and post-pollination treatment on durum wheat haploid embryos produced by durum wheat x maize crosses and the use of the endosperm nursing technique for haploid plantlets regeneration were investigated. The haploid induction parameters varied with the durum wheat genotypes as well as the post-pollination treatments. The phenomenon of polyembryony resulting from durum wheat x maize crosses is reported for the first time in this article. The durum wheat genotypes showed different abilities to produce monoembryo and polyembryos. The post-pollination treatments with 2,4-D (10 mg.L-1) and Picloram (10 and 100 mg.L-1) gave a higher embryo formation frequency than the treatments with Dicamba. The embryo conversion to plantlet was greatly improved, especially in recalcitrant genotypes using the durum wheat endosperm as supplemental nourishment in combination with the Gamborg B5 regeneration medium.Keywords: Durum wheat; Haploid embryo; Maize; Nurse Endosperm Technique; Polyembryony

    Use of nurse endosperm for the culture of haploid embryos produced by durum wheat x maize crosses

    No full text
    The use of doubled-haploids in plant breeding programs enables accelerating the release of new varieties adapted to climate change. The durum wheat x maize crosses technique is a method of choice for producing durum wheat haploid plants. The haploid embryos produced by this method develop without albumen and their survival is ensured by post-pollination hormonal treatments. In this study, nine post-pollination treatments with 2,4-Dichlorophenoxyacetic acid (2,4-D), Picloram and Dicamba at the concentrations of 10, 50 and 100 mg.L-1 were applied to 7 durum wheat genotypes. The effects of genotype and post-pollination treatment on durum wheat haploid embryos produced by durum wheat x maize crosses and the use of the endosperm nursing technique for haploid plantlets regeneration were investigated. The haploid induction parameters varied with the durum wheat genotypes as well as the post-pollination treatments. The phenomenon of polyembryony resulting from durum wheat x maize crosses is reported for the first time in this article. The durum wheat genotypes showed different abilities to produce monoembryo and polyembryos. The post-pollination treatments with 2,4-D (10 mg.L-1) and Picloram (10 and 100 mg.L-1) gave a higher embryo formation frequency than the treatments with Dicamba. The embryo conversion to plantlet was greatly improved, especially in recalcitrant genotypes using the durum wheat endosperm as supplemental nourishment in combination with the Gamborg B5 regeneration medium.Keywords: Durum wheat; Haploid embryo; Maize; Nurse Endosperm Technique; Polyembryony

    Neuromuscular fatigue and recovery profiles in individuals with intellectual disability

    No full text
    Purpose: This study aimed to explore neuromuscular fatigue and recovery profiles in individuals with intellectual disability (ID) after exhausting submaximal contraction. Methods: Ten men with ID were compared to 10 men without ID. The evaluation of neuromuscular function consisted in brief (3 s) isometric maximal voluntary contraction (IMVC) of the knee extension superimposed with electrical nerve stimulation before, immediately after, and during 33 min after an exhausting submaximal isometric task at 15% of the IMVC. Force, voluntary activation level (VAL), potentiated twitch (Ptw), and electromyography (EMG) signals were measured during IMVC and then analyzed. Results: Individuals with ID developed lower baseline IMVC, VAL, Ptw, and RMS/Mmax ratio (root-mean-square value normalized to the maximal peak-to-peak amplitude of the M-wave) than controls (p < 0.05). Nevertheless, the time to task failure was significantly longer in ID vs. controls (p < 0.05). The 2 groups presented similar IMVC decline and recovery kinetics after the fatiguing exercise. However, individuals with ID presented higher VAL and RMS/Mmax ratio declines but lower Ptw decline compared to those without ID. Moreover, individuals with ID demonstrated a persistent central fatigue but faster recovery from peripheral fatigue. Conclusion: These differences in neuromuscular fatigue profiles and recovery kinetics should be acknowledged when prescribing training programs for individuals with ID. Keywords: Central fatigue, Intellectual disability, Neuromuscular fatigue, Peripheral fatigue, Sustained sub-maximal exercise, Twitch interpolation techniqu
    corecore