101 research outputs found

    Associating Facial Expressions and Upper-Body Gestures with Learning Tasks for Enhancing Intelligent Tutoring Systems

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    Learning involves a substantial amount of cognitive, social and emotional states. Therefore, recognizing and understanding these states in the context of learning is key in designing informed interventions and addressing the needs of the individual student to provide personalized education. In this paper, we explore the automatic detection of learner’s nonverbal behaviors involving hand-over-face gestures, head and eye movements and emotions via facial expressions during learning. The proposed computer vision-based behavior monitoring method uses a low-cost webcam and can easily be integrated with modern tutoring technologies. We investigate these behaviors in-depth over time in a classroom session of 40 minutes involving reading and problem-solving exercises. The exercises in the sessions are divided into three categories: an easy, medium and difficult topic within the context of undergraduate computer science. We found that there is a significant increase in head and eye movements as time progresses, as well as with the increase of difficulty level. We demonstrated that there is a considerable occurrence of hand-over-face gestures (on average 21.35%) during the 40 minutes session and is unexplored in the education domain. We propose a novel deep learning approach for automatic detection of hand-over-face gestures in images with a classification accuracy of 86.87%. There is a prominent increase in hand-over-face gestures when the difficulty level of the given exercise increases. The hand-over-face gestures occur more frequently during problem-solving (easy 23.79%, medium 19.84% and difficult 30.46%) exercises in comparison to reading (easy 16.20%, medium 20.06% and difficult 20.18%)

    A large-scale study on the effects of sex on gray matter asymmetry

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    Research on sex-related brain asymmetries has not yielded consistent results. Despite its importance to further understanding of normal brain development and mental disorders, the field remains relatively unexplored. Here we employ a recently developed asymmetry measure, based on the Dice coefficient, to detect sex-related gray matter asymmetries in a sample of 457 healthy participants (266 men and 191 women) obtained from 5 independent databases. Results show that women’s brains are more globally symmetric than men’s (p < 0.001). Although the new measure accounts for asymmetries distributed all over the brain, several specific structures were identified as systematically more symmetric in women, such as the thalamus and the cerebellum, among other structures, some of which are typically involved in language production. These sex-related asymmetry differences may be defined at the neurodevelopmental stage and could be associated with functional and cognitive sex differences, as well as with proneness to develop a mental disorder

    In vitro assessment of adsorbents aiming to prevent deoxynivalenol and zearalenone mycotoxicoses

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    The high prevalence of the Fusarium mycotoxins, deoxynivalenol (DON) and zearalenone (ZON) in animal feeds in mild climatic zones of Europe and North America results in considerable economic losses, as these toxins affect health and productivity particularly of pigs from all age groups. The use of mycotoxin adsorbents as feed additives is one of the most prominent approaches to reduce the risk for mycotoxicoses in farm animals, and to minimise carry-over of mycotoxins from contaminated feeds into foods of animal origin. Successful aflatoxin adsorption by means of different substances (phyllosilicate minerals, zeolites, activated charcoal, synthetic resins or yeast cell-wall-derived products) has been demonstrated in vivo and in vitro. However, attempts to adsorb DON and ZON have been less encouraging. Here we describe the adsorption capacity of a variety of potential binders, including compounds that have not been evaluated before, such as humic acids. All compounds were tested at realistic inclusion levels for their capacity to bind ZON and DON, using an in vitro method that resembles the different pH conditions in the gastro-intestinal tract of pigs. Mycotoxin adsorption was assessed by chemical methods and distinct bioassays, using specific markers of toxicity as endpoints of toxicity in cytological assays. Whereas none of the tested substances was able to bind DON in an appreciable percentage, some of the selected smectite clays, humic substances and yeast-wall derived products efficiently adsorbed ZON (>70%). Binding efficiency was indirectly confirmed by the reduction of toxicity in the in vitro bioassays. In conclusion, the presented test protocol allows the rapid screening of potential mycotoxin binders. Like other in vitro assays, the presented protocol combining chemical and biological assays cannot completely simulate the conditions of the gastro-intestinal tract, and hence in vivo experiments remain mandatory to assess the efficacy of mycotoxin binders under practical conditions

    Delineating the Factors and Cellular Mechanisms Involved in the Survival of Cerebellar Granule Neurons

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    Cerebellar granule neurons (CGNs) constitute the most abundant neuronal population in the mammalian brain. Their postnatal generation and the feasibility to induce their apoptotic death in vitro make them an excellent model to study the effect of several neurotransmitters and neurotrophins. Here, we first review which factors are involved in the generation and proliferation of CGNs in the external granule layer (EGL) and in the regulation of their differentiation and migration to internal granule layer (IGL). Special attention was given to the role of several neurotrophins and the NMDA subtype of glutamate receptor. Then, using the paradigm of potassium deprivation in cultured CGNs, we address several extracellular factors that promote the survival of CGNs, with particular emphasis on the cellular mechanisms. The role of specific protein kinases leading to the regulation of transcription factors and recent data involving the small G protein family is also discussed. Finally, the participation of some members of Bcl-2 family and the inhibition of mitochondria-related apoptotic pathway is also considered. Altogether, these studies evidence that CGNs are a key model to understand the development and the survival of neuronal population

    Consensus Paper: Cerebellum and Social Cognition.

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    The traditional view on the cerebellum is that it controls motor behavior. Although recent work has revealed that the cerebellum supports also nonmotor functions such as cognition and affect, only during the last 5 years it has become evident that the cerebellum also plays an important social role. This role is evident in social cognition based on interpreting goal-directed actions through the movements of individuals (social "mirroring") which is very close to its original role in motor learning, as well as in social understanding of other individuals' mental state, such as their intentions, beliefs, past behaviors, future aspirations, and personality traits (social "mentalizing"). Most of this mentalizing role is supported by the posterior cerebellum (e.g., Crus I and II). The most dominant hypothesis is that the cerebellum assists in learning and understanding social action sequences, and so facilitates social cognition by supporting optimal predictions about imminent or future social interaction and cooperation. This consensus paper brings together experts from different fields to discuss recent efforts in understanding the role of the cerebellum in social cognition, and the understanding of social behaviors and mental states by others, its effect on clinical impairments such as cerebellar ataxia and autism spectrum disorder, and how the cerebellum can become a potential target for noninvasive brain stimulation as a therapeutic intervention. We report on the most recent empirical findings and techniques for understanding and manipulating cerebellar circuits in humans. Cerebellar circuitry appears now as a key structure to elucidate social interactions

    The bile salt glycocholate induces global changes in gene and protein expression and activates virulence in enterotoxigenic Escherichia coli

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    Pathogenic bacteria use specific host factors to modulate virulence and stress responses during infection. We found previously that the host factor bile and the bile component glyco-conjugated cholate (NaGCH, sodium glycocholate) upregulate the colonization factor CS5 in enterotoxigenic Escherichia coli (ETEC). To further understand the global regulatory effects of bile and NaGCH, we performed Illumina RNA-Seq and found that crude bile and NaGCH altered the expression of 61 genes in CS5 + CS6 ETEC isolates. The most striking finding was high induction of the CS5 operon (csfA-F), its putative transcription factor csvR, and the putative ETEC virulence factor cexE. iTRAQ-coupled LC-MS/MS proteomic analyses verified induction of the plasmid-borne virulence proteins CS5 and CexE and also showed that NaGCH affected the expression of bacterial membrane proteins. Furthermore, NaGCH induced bacteria to aggregate, increased their adherence to epithelial cells, and reduced their motility. Our results indicate that CS5 + CS6 ETEC use NaGCH present in the small intestine as a signal to initiate colonization of the epithelium

    Microbiota and chronic inflammatory arthritis: an interwoven link

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