254 research outputs found
A theoretical framework for trading experiments
A general framework is suggested to describe human decision making in a
certain class of experiments performed in a trading laboratory. We are in
particular interested in discerning between two different moods, or states of
the investors, corresponding to investors using fundamental investment
strategies, technical analysis investment strategies respectively. Our
framework accounts for two opposite situations already encountered in
experimental setups: i) the rational expectations case, and ii) the case of
pure speculation. We consider new experimental conditions which allow both
elements to be present in the decision making process of the traders, thereby
creating a dilemma in terms of investment strategy. Our theoretical framework
allows us to predict the outcome of this type of trading experiments, depending
on such variables as the number of people trading, the liquidity of the market,
the amount of information used in technical analysis strategies, as well as the
dividends attributed to an asset. We find that it is possible to give a
qualitative prediction of trading behavior depending on a ratio that quantifies
the fluctuations in the model
Pax2 and Pax8 cooperate in mouse inner ear morphogenesis and innervation
<p>Abstract</p> <p>Background</p> <p><it>Pax2;5;8 </it>transcription factors play diverse roles in vertebrate and invertebrate organogenesis, including the development of the inner ear. Past research has suggested various cochlear defects and some vestibular defects in <it>Pax2 </it>null mice but the details of the cochlear defects and the interaction with other <it>Pax </it>family members in ear development remain unclear.</p> <p>Results</p> <p>We show that <it>Pax2;8 </it>double null mice do not develop an ear past the otocyst stage and show little to no sensory as well as limited and transient neuronal development, thus indicating that these two family members are essential for overall ear morphogenesis and sustained neurosensory development. In support of functional redundancy between Pax proteins, <it>Pax2 </it>can be substituted by a <it>Pax5 </it>minigene, a gene normally not expressed in the embryonic mouse ear. There is no detectable morphological defect in <it>Pax8 </it>null mice suggesting that <it>Pax2 </it>expression can compensate for <it>Pax8</it>. Conversely, <it>Pax8 </it>cannot compensate for <it>Pax2 </it>leading to a cochlear phenotype not fully appreciated previously: Cochlear development is delayed until E15.5 when the cochlea extrudes as a large sack into the brain case. Immunocytochemistry and tracing from the brain show that a cochlear spiral ganglia form as a small addition to the inferior vestibular ganglion. However, the empty cochlear sack, devoid of any sensory epithelium development as indicated by the absence of Sox2 or MyoVII expression, nevertheless develop a dense innervation network of small neurons situated in the wall of the cochlear sack.</p> <p>Conclusions</p> <p>Combined these data suggest that <it>Pax2 </it>is needed for organ of Corti formation and is directly or indirectly involved in the coordination of spiral ganglion formation which is partially disrupted in the <it>Pax2 </it>null ears. All three <it>Pax </it>genes can signal redundantly in the ear with their function being determined primarily by the spatio-temporal expression driven by the three distinct promoters of these genes.</p
Association between recreational screen time and sleep quality among adolescents during the third wave of the COVID-19 pandemic in Canada
The study objective was to verify whether recreational screen time was associated with sleep quality among adolescents during the third wave of the COVID-19 pandemic in Canada. Data collection took place in four high schools in the region of Chaudière-Appalaches (Quebec, Canada) from the end of April to mid-May 2021. Recreational screen time and sleep quality were measured using the French versions of validated questionnaires specifically designed for adolescents. A total of 258 adolescents (14–18 years; 66.3% girls) answered the online survey. Adolescent boys had a higher total mean recreational screen time (454.3 ± 197.5 vs. 300.5 ± 129.3 min/day, p < 0.0001) and a higher total mean sleep quality score (4.2 ± 0.9 vs. 3.9 ± 0.8, p = 0.0364) compared to girls. Recreational screen time (β = −0.0012, p = 0.0005) and frequency of concurrent screen use (sometimes: β = −0.3141, p = 0.0269; often: β = −0.4147, p = 0.0048; almost always or always: β = −0.6155, p = 0.0002) were negatively associated with sleep quality while being a boy (β = 0.4276, p = 0.0004) was positively associated with sleep quality and age (p = 0.6321) was not. This model explained 16% of the variance in adolescents’ sleep quality. Public health interventions during and after the COVID-19 pandemic should target recreational screen time, concurrent screen use and especially girls to possibly improve sleep quality and promote adolescents’ physical and mental health
Psychosocial correlates of recreational screen time among adolescents
The study objective was to identify the psychosocial correlates of recreational screen time among adolescents. Data collection took place in four high schools from the Chaudière-Appalaches region (Quebec, Canada) from late April to mid-May 2021. A total of 258 French-speaking adolescents (69.8% between 15 and 16 years and 66.3% girls) answered an online questionnaire based on the Reasoned Action Approach. Recreational screen time was measured using the French version of a validated questionnaire. Adolescents reported a mean of 5 h and 52 min/day of recreational screen time. Recreational screen time was associated with being a boy (β = 0.33; p < 0.0001) and intention to limit recreational screen time to a maximum of 2 h/day (β = −0.15; p = 0.0001); this model explained 30% of the variance in behavior. Intention to limit recreational screen time to a maximum of 2 h/day in the next month was associated with attitude (β = 0.49; p < 0.0001), self-identity (β = 0.33; p < 0.0001), being a boy (β = −0.21; p = 0.0109), perceived behavioral control (β = 0.18; p = 0.0016), and injunctive norm (β = 0.17; p < 0.0001); this model explained 70% of the variance in intention. This study identified avenues to design public health interventions aimed at lowering recreational screen time among this population
Identité et abandon scolaire selon le genre en milieu collégial rapport de recherche /
La présente recherche a été subventionnée par le ministère de l'Éducation, du Loisir et du Sport dans le cadre du Programme d'aide à la recherche sur l'enseignement et l'apprentissage (PAREA)Également disponible en version papier.Titre de l'écran-titre (visionné le 28 août 2012
Identité et abandon scolaire selon le genre en milieu collégial article de vulgarisation /
La présente recherche a été subventionnée par le ministère de l'Éducation, du Loisir et du Sport dans le cadre du Programme d'aide à la recherche sur l'enseignement et l'apprentissage (PAREA)Également disponible en version papier
A virtual classroom can elicit teachers’ speech characteristics: Evidence from acoustic measurements during in vivo and in virtuo lessons, compared to a free speech control situation
peer reviewedTo achieve pedagogic goals and deal with environmental constraints such as noise when lecturing, teachers adapt their speech production in terms of frequency, intensity, and temporal aspects. The mastery of appropriate vocal skills is key to teachers’ speech intelligibility, health, and educational effectiveness. This project tests the relevance of virtual reality (VR) for training teachers’ vocal skills by simulating a lesson in a realistic VR environment characterized by adjustable constraints such as background noise and fidgety children. The VR environment depicts an elementary school classroom with 16 pupils aged 9 to 12 years old animated with typical childlike actions.
To validate this virtual classroom in terms of speech characteristics, we conducted acoustic analyses on the speech productions of 30 female teachers in three conditions: (1) giving a free speech while facing the experimenter (control), (2) teaching in their usual classroom (in vivo), and (3) teaching the same lesson in a virtual classroom (in virtuo). The background noise in the VR setting was adjusted for each talker so it was similar to the level measured in vivo.
Repeated measures ANOVAs showed that teachers significantly increased their voice frequency, intensity, and intonation, and made longer pauses while speaking in vivo and in virtuo, compared to the control condition (p < .001). These voice and speech adaptations (partly related to background noise), the strong feeling of presence and the lack of side effects suggest that the virtual classroom may facilitate voice training and rehabilitation for teachers.VirtuVo
Global Properties of Topological String Amplitudes and Orbifold Invariants
We derive topological string amplitudes on local Calabi-Yau manifolds in
terms of polynomials in finitely many generators of special functions. These
objects are defined globally in the moduli space and lead to a description of
mirror symmetry at any point in the moduli space. Holomorphic ambiguities of
the anomaly equations are fixed by global information obtained from boundary
conditions at few special divisors in the moduli space. As an illustration we
compute higher genus orbifold Gromov-Witten invariants for C^3/Z_3 and C^3/Z_4.Comment: 34 pages, 3 figure
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