Epistemic and social scripts in computer-supported collaborative learning

Collaborative learning in computer-supported learning environments typically means that learners work on tasks together, discussing their individual perspectives via text-based media or videoconferencing, and consequently acquire knowledge. Collaborative learning, however, is often sub-optimal with respect to how learners work on the concepts that are supposed to be learned and how learners interact with each other. One possibility to improve collaborative learning environments is to conceptualize epistemic scripts, which specify how learners work on a given task, and social scripts, which structure how learners interact with each other. In this contribution, two studies will be reported that investigated the effects of epistemic and social scripts in a text-based computer-supported learning environment and in a videoconferencing learning environment in order to foster the individual acquisition of knowledge. In each study the factors ‘epistemic script’ and ‘social script’ have been independently varied in a 2×2-factorial design. 182 university students of Educational Science participated in these two studies. Results of both studies show that social scripts can be substantially beneficial with respect to the individual acquisition of knowledge, whereas epistemic scripts apparently do not to lead to the expected effects

Making Sense Through Participation

In this chapter we discuss the issue of social differences in relation to learning. In theories on co-operative learning or collaborative learning social differences are treated as characteristics of individual learners. The focus on learning as a social process is primarily elaborated in terms of interaction between pupils and the combined construction of knowledge. Sociocultural theory (Vygotsky, Lave & Wenger), however, understands ‘social’ not only in terms of knowledge/meaning being constructed in interaction with others, but also in terms of the cultural practices/activities informing these interaction processes. Learning can be understood as increasing participating in communities of practice. As social differences are an intrinsic part of the culture in which students are learning to participate, these are also an inherent aspect of learning processes in schools. Students learn to participate in practices in different ways, depending on their social position, and thus develop distinguished cultural identities. In this chapter we elaborate on this tenet, using examples from various empirical research projects on learning in secondary education. We not only show how social differences in the cultural practices that underpin learning influence what is learned by whom, but also explore the consequences of this perspective for the pedagogical space of the school

Baseline fat fraction is a strong predictor of disease progression in Becker muscular dystrophy

In Becker muscular dystrophy (BMD), muscle weakness progresses relatively slowly, with a highly variable rate among patients. This complicates clinical trials, as clinically relevant changes are difficult to capture within the typical duration of a trial. Therefore, predictors for disease progression are needed. We assessed if temporal increase of fat fraction (FF) in BMD follows a sigmoidal trajectory and whether fat fraction at baseline (FFbase) could therefore predict FF increase after 2 years (Delta FF). Thereafter, for two different MR-based parameters, we tested the additional predictive value to FFbase. We used 3-T Dixon data from the upper and lower leg, and multiecho spinecho MRI and 7-T P-31 MRS datasets from the lower leg, acquired in 24 BMD patients (age: 41.4 [SD 12.8] years). We assessed the pattern of increase in FF using mixed-effects modelling. Subsequently, we tested if indicators of muscle damage like standard deviation in water T-2 (stdT(2)) and the phosphodiester (PDE) over ATP ratio at baseline had additional value to FFbase for predicting Delta FF. The association between FFbase and Delta FF was described by the derivative of a sigmoid function and resulted in a peak Delta FF around 0.45 FFbase (fourth-order polynomial term: t = 3.7, p < .001). StdT(2) and PDE/ATP were not significantly associated with Delta FF if FFbase was included in the model. The relationship between FFbase and Delta FF suggests a sigmoidal trajectory of the increase in FF over time in BMD, similar to that described for Duchenne muscular dystrophy. Our results can be used to identify muscles (or patients) that are in the fast progressing stage of the disease, thereby facilitating the conduct of clinical trials.Orthopaedics, Trauma Surgery and Rehabilitatio

Muscle architecture is associated with muscle fat replacement in Duchenne and Becker muscular dystrophies

Introduction/Aims Duchenne and Becker muscular dystrophies (DMD and BMD, respectively) are characterized by fat replacement of different skeletal muscles in a specific temporal order. Given the structural role of dystrophin in skeletal muscle mechanics, muscle architecture could be important in the progressive pathophysiology of muscle degeneration. Therefore, the aim of this study was to assess the role of muscle architecture in the progression of fat replacement in DMD and BMD. Methods We assessed the association between literature-based leg muscle architectural characteristics and muscle fat fraction from 22 DMD and 24 BMD patients. Dixon-based magnetic resonance imaging estimates of fat fractions at baseline and 12 (only DMD) and 24 months were related to fiber length and physiological cross-sectional area (PCSA) using age-controlled linear mixed modeling. Results DMD and BMD muscles with long fibers and BMD muscles with large PCSAs were associated with increased fat fraction. The effect of fiber length was stronger in muscles with larger PCSA. Discussion Muscle architecture may explain the pathophysiology of muscle degeneration in dystrophinopathies, in which proximal muscles with a larger mass (fiber length x PCSA) are more susceptible, confirming the clinical observation of a temporal proximal-to-distal progression. These results give more insight into the mechanical role in the pathophysiology of muscular dystrophies. Ultimately, this new information can be used to help support the selection of current and the development of future therapies.Neuro Imaging Researc

Mediators of lifestyle behaviour changes in obese pregnant women. Secondary analyses from the DALI lifestyle randomised controlled trial

A better understanding of what drives behaviour change in obese pregnant overweight women is needed to improve the effectiveness of lifestyle interventions in this group at risk for gestational diabetes (GDM). Therefore, we assessed which factors mediated behaviour change in the Vitamin D and Lifestyle Intervention for GDM Prevention (DALI) Lifestyle Study. A total of 436 women, with pre-pregnancy body mass index ≥29 kg/m 2 , ≤19 + 6 weeks of gestation and without GDM, were randomised for counselling based on motivational interviewing (MI) on healthy eating and physical activity, healthy eating alone, physical activity alone, or to a usual care group. Lifestyle was measured at baseline, and at 24–28 and 35–37 weeks of gestation. Outcome expectancy, risk perception, task self-efficacy and social support were measured at those same time points and considered as possible mediators of intervention effects on lifestyle. All three interventions resulted in increased positive outcome expectancy for GDM reduction, perceived risk to the baby and increased task self-efficacy. The latter mediated intervention effects on physical activity and reduced sugared drink consumption. In conclusion, our MI intervention was successful in increasing task self-efficacy, which was related to improved health behaviours

Phosphorothioate antisense oligonucleotides induce the formation of nuclear bodies

Antisense oligonucleotides are powerful tools for the in vivo regulation of gene expression. We have characterized the intracellular distribution of fluorescently tagged phosphorothioate oligodeoxynucleotides (PS-ONs) at high resolution under conditions in which PS-ONs have the potential to display antisense activity. Under these conditions PS-ONs predominantly localized to the cell nucleus where they accumulated in 20-30 bright spherical foci designated phosphorothioate bodies (PS bodies), which were set against a diffuse nucleoplasmic population excluding nucleoli. PS bodies are nuclear structures that formed in cells after PS-ON delivery by transfection agents or microinjection but were observed irrespectively of antisense activity or sequence. Ultrastructurally, PS bodies corresponded to electron-dense structures of 150-300 nm diameter and resembled nuclear bodies that were found with lower frequency in cells lacking PS-ONs. The environment of a living cell was required for the de novo formation of PS bodies, which occurred within minutes after the introduction of PS-ONs. PS bodies were stable entities that underwent noticeable reorganization only during mitosis. Upon exit from mitosis, PS bodies were assembled de novo from diffuse PS-ON pools in the daughter nuclei. In situ fractionation demonstrated an association of PS-ONs with the nuclear matrix. Taken together, our data provide evidence for the formation of a nuclear body in cells after introduction of phosphorothioate oligodeoxynucleotides

Modeling body size evolution in Felidae under alternative phylogenetic hypotheses

The use of phylogenetic comparative methods in ecological research has advanced during the last twenty years, mainly due to accurate phylogenetic reconstructions based on molecular data and computational and statistical advances. We used phylogenetic correlograms and phylogenetic eigenvector regression (PVR) to model body size evolution in 35 worldwide Felidae (Mammalia, Carnivora) species using two alternative phylogenies and published body size data. The purpose was not to contrast the phylogenetic hypotheses but to evaluate how analyses of body size evolution patterns can be affected by the phylogeny used for comparative analyses (CA). Both phylogenies produced a strong phylogenetic pattern, with closely related species having similar body sizes and the similarity decreasing with increasing distances in time. The PVR explained 65% to 67% of body size variation and all Moran's I values for the PVR residuals were non-significant, indicating that both these models explained phylogenetic structures in trait variation. Even though our results did not suggest that any phylogeny can be used for CA with the same power, or that “good” phylogenies are unnecessary for the correct interpretation of the evolutionary dynamics of ecological, biogeographical, physiological or behavioral patterns, it does suggest that developments in CA can, and indeed should, proceed without waiting for perfect and fully resolved phylogenies

Developmental trajectories of infants with multiplex family risk for Autism: a Baby Siblings Research Consortium Study

Importance: Autism spectrum disorder (ASD) is a neurodevelopmental disorder associated with different genetic etiologies. Prospective examination of familial-risk infants informs understanding of developmental trajectories preceding ASD diagnosis, potentially improving early detection. Objective: Compare outcomes and trajectories associated with varying familial risk for ASD across first 3 years of life. Design and Setting: Longitudinal, prospective observational study. Data from 11 sites in Baby Siblings Research Consortium (BSRC) database included. Data collected between 2003-2015. Infants followed for 3 years. Analyses conducted in 2018. Participants: Of initial 1,008 infants from BSRC database, 573 removed due to missing necessary data, diagnostic discrepancies, or only one older sibling. 435 younger siblings of children with ASD included; 355 from single-incidence families (1 sibling with ASD and 1+ sibling without ASD) and 80 from multiplex families (2+ siblings with ASD). No group differences in major demographics. Exposure: Number of ASD-siblings. Main Outcomes and Measures: Outcomes included ASD symptoms, cognitive abilities, and adaptive skills. Diagnosis (ASD/no-ASD) given at 36-month outcome. No-ASD group classified as atypical (developmental delays and/or social-communication concerns) or typical for some analyses. Generalized linear mixed models examined developmental trajectories by ASD outcome and familial-risk group. Results: In the 435 analyzed participants (age range at outcome: 32-43 months; 57% male), children from multiplex families were more likely than those from single-incidence families to 5 be classified as ASD (36% vs. 16%, p<.001) and less likely as typical (33% vs. 57%, p<.001), with similar rates of atypical classifications (31% vs. 27%, p=.49). No differences in ASD symptoms between multiplex and single-incidence groups, after controlling for ASD outcome (p=.18). During infancy, differences in cognitive and adaptive abilities observed based upon ASD outcome in single-incidence group only (ps<.001-.04). At 36 months, multiplex/no-ASD group had lower cognitive abilities than single-incidence/no-ASD group (p=.02), and multiplex had lower adaptive abilities than single-incidence, after controlling for ASD outcome (p=.02). Conclusions and Relevance: Infants with a multiplex family history of ASD should be monitored early and often and referred for early intervention at the first sign of concern. Direct examination of genetic contributions to neurodevelopmental phenotypes in infants with familial risk for ASD is needed