28 research outputs found

    Towards a synthetic tutor assistant: The EASEL project and its architecture

    Get PDF
    Robots are gradually but steadily being introduced in our daily lives. A paramount application is that of education, where robots can assume the role of a tutor, a peer or simply a tool to help learners in a specific knowledge domain. Such endeavor posits specific challenges: affective social behavior, proper modelling of the learner’s progress, discrimination of the learner’s utterances, expressions and mental states, which, in turn, require an integrated architecture combining perception, cognition and action. In this paper we present an attempt to improve the current state of robots in the educational domain by introducing the EASEL EU project. Specifically, we introduce the EASEL’s unified robot architecture, an innovative Synthetic Tutor Assistant (STA) whose goal is to interactively guide learners in a science-based learning paradigm, allowing us to achieve such rich multimodal interactions

    Noise Reduction by Diffusional Dissipation in a Minimal Quorum Sensing Motif

    Get PDF
    Cellular interactions are subject to random fluctuations (noise) in quantities of interacting molecules. Noise presents a major challenge for the robust function of natural and engineered cellular networks. Past studies have analyzed how noise is regulated at the intracellular level. Cell–cell communication, however, may provide a complementary strategy to achieve robust gene expression by enabling the coupling of a cell with its environment and other cells. To gain insight into this issue, we have examined noise regulation by quorum sensing (QS), a mechanism by which many bacteria communicate through production and sensing of small diffusible signals. Using a stochastic model, we analyze a minimal QS motif in Gram-negative bacteria. Our analysis shows that diffusion of the QS signal, together with fast turnover of its transcriptional regulator, attenuates low-frequency components of extrinsic noise. We term this unique mechanism “diffusional dissipation” to emphasize the importance of fast signal turnover (or dissipation) by diffusion. We further show that this noise attenuation is a property of a more generic regulatory motif, of which QS is an implementation. Our results suggest that, in a QS system, an unstable transcriptional regulator may be favored for regulating expression of costly proteins that generate public goods

    The Emergence and Development of Association Football: Influential Sociocultural Factors in Victorian Birmingham

    Get PDF
    This article explores the interdependent, complex sociocultural factors that facilitated the emergence and diffusion of football in Birmingham. The focus is the development of football in the city, against the backdrop of the numerous social changes in Victorian Birmingham. The aim is to fill a gap in the existing literature which seemingly overlooked Birmingham as a significant footballing centre, and the ‘ordinary and everyday’ aspects of the game’s early progression. Among other aspects, particular heed is paid to the working classes’ involvement in football, as previous literature has often focused on the middle classes and their influence on and participation in organized sport. As the agency of the working classes along with their mass participation and central role in the game’s development is unfolded, it is argued that far from being passive cultural beings, the working classes, from the beginnings, actively negotiated the development of their own emergent football culture

    Genome-Wide and Phase-Specific DNA-Binding Rhythms of BMAL1 Control Circadian Output Functions in Mouse Liver

    Get PDF
    Temporal mapping during a circadian day of binding sites for the BMAL1 transcription factor in mouse liver reveals genome-wide daily rhythms in DNA binding and uncovers output functions that are controlled by the circadian oscillator

    Light microscopic evaluation and scanning electron microscopic analysis of horse eyes following deep anterior lamellar keratectomy

    No full text
    Objective To describe the technique of deep anterior lamellar keratoplasty (DALK) with Descemet's membrane (DM) exposure in horse eyes. Also, to compare the efficacy and safety of viscodissection and big-bubble techniques for DALK. Animals studied Thirty-four ex vivo horse eyes. Procedure Deep anterior lamellar keratoplasty was performed in 34 ex vivo horse eyes. Two groups (Group V - viscodissection - 2% sodium hyaluronate; Group A - air - big-bubble) of 17 eyes were studied. Other than the substance used, the surgical technique was similar for both groups. Nonperforated eyes were submitted for light microscopic histologic evaluation and scanning electron microscopic (SEM) analysis. Results Group V - Perforations occurred in 18% of the eyes during surgery. Light microscopy revealed exposure of DM in 28% of the eyes with mean thickness of the remaining stroma being 70.4Όm. Group A - Perforations occurred in 42% of the eyes. Light microscopy revealed exposure of DM in 60% of the eyes with mean thickness of the remaining stroma being 23.3Όm. No significant differences in safety, efficacy and thickness of the remaining stroma (including all eyes or excluding those with DM exposure) were observed. SEM of the surgical site revealed a more even surface in those eyes with DM exposure compared to eyes with thicker remaining stroma in both groups. Conclusions We describe two DALK techniques (viscodissection and big-bubble) for use in horses. No significant differences in safety, efficacy and thickness of the remaining stroma were observed. However, a nonsignificant trend toward the big-bubble technique being more efficacious but less safe was observed. © 2012 American College of Veterinary Ophthalmologists
    corecore