4,228 research outputs found
Space exploration by the promoter of a long human gene during one transcription cycle
An RNA polymerase has been thought to transcribe by seeking out a promoter, initiating and then tracking down the template. We add tumor necrosis factor α to primary human cells, switch on transcription of a 221-kb gene and monitor promoter position during the ensuing transcription cycle (using RNA fluorescence in situ hybridization coupled to super-resolution localization, chromosome conformation capture and Monte Carlo simulations). Results are consistent with a polymerase immobilized in a 'factory' capturing a promoter and reeling in the template, as the transcript and promoter are extruded. Initially, the extruded promoter is tethered close to the factory and so likely to re-initiate; later, the tether becomes long enough to allow re-initiation in another factory. We suggest close tethering underlies enhancer function and transcriptional 'bursting'
Pathways from maternal depressive symptoms to adolescent depressive symptoms:the unique contribution of irritability symptoms
BACKGROUND: The authors tested three possible pathways linking prenatal maternal depressive symptoms to adolescent depressive symptoms. These pathways went through childhood Irritability Symptoms, Anxiety/Depressive Symptoms or Conduct Problems. METHOD: Data were collected from 3,963 mother–child pairs participating in the Avon Longitudinal Study of Parents and Children. Measures include maternal depressive symptoms (pre‐ and postnatal); toddler temperament (2 years); childhood (7–13 years) irritability symptoms, anxiety/depressive symptoms, conduct problems, and adolescent depressive symptoms (16 years). RESULTS: Irritability Symptoms: This pathway linked sequentially – prenatal maternal depressive symptoms, toddler temperament (high perceived intensity and low perceived adaptability), childhood irritability symptoms, and adolescent depressive symptoms. Anxiety/Depressive symptoms: This pathway linked sequentially – prenatal maternal depressive symptoms, toddler temperament (negative perceived mood), childhood anxiety/depressive symptoms, and adolescent depressive symptoms. Childhood conduct problems were not associated with adolescent depressive symptoms, above and beyond irritability symptoms and anxiety/depressive symptoms. CONCLUSIONS: Results suggest evidence for two distinct developmental pathways to adolescent depressive symptoms that involve specific early and midchildhood features
When team identity helps innovation and when it hurts:team identity and its relationship to team and cross-team innovative behavior
Although the success of team-based organizations requires innovative behavior within and across teams, little research has considered how to foster both types of activity. This is problematic as strong team attachments such as team identification may have mixed effects on team innovative behavior, and may even negatively impact cross-team innovative behavior. We explain these mixed effects through intra- and intergroup aspects of social identity theory and the concept of team reflexivity. We propose that effects of team identification on team innovative behavior are contingent upon team reflexivity, such that team identification is positively related to team innovative behavior only when team reflexivity is high. We also propose that where a team’s innovative behavior involves working across team boundaries with other teams, i.e. cross-team innovative behavior, this interaction between team identification and reflexivity is further qualified by perceived interdependence with another team. In a sample of 61 Turkish research and development (R&D) teams comprising 305 employees and 61 team leaders, we find that the association between team identity and team innovative behavior was moderated by team reflexivity as predicted. Further, team identity was positively associated with cross-team innovative behavior only when reflexivity and perceived interdependence between teams were both high, and negatively associated when reflexivity was low and perceived interdependence between teams was high
Evaluating megaprojects: from the “iron triangle” to network mapping
Evaluation literature has paid relatively little attention to the specific needs of evaluating large, complex industrial and infrastructure projects, often called ‘megaprojects’. The abundant megaproject governance literature, in turn, has largely focused on the so-called ‘megaproject pathologies’, i.e. the chronic budget overruns, and failure of such projects to keep to timetables and deliver the expected social and economic benefits. This article draws on these two strands of literature, identifies shortcomings, and suggests potential pathways towards an improved evaluation of megaprojects. To counterbalance the current overemphasis on relatively narrowly defined accountability as the main function of megaproject evaluation, and the narrow definition of project success in megaproject evaluation, the article argues that conceptualizing megaprojects as dynamic and evolving networks would provide a useful basis for the design of an evaluation approach better able to promote learning and to address the socio economic aspects of megaprojects. A modified version of ‘network mapping’ is suggested as a possible framework for megaproject evaluation, with the exploration of the multiple accountability relationships as a central evaluation task, designed to reconcile learning and accountability as the central evaluation functions. The article highlights the role of evaluation as an ‘emergent’ property of spontaneous megaproject ‘governing’, and explores the challenges that this poses to the role of the evaluator
Three-Dimensional Tibiofemoral Kinematics of the Anterior Cruciate Ligament-Deficient and Reconstructed Knee during Walking
Background: It is possible that gait abnormalities may play a role in the pathogenesis of meniscal or chondral injury as well as osteoarthritis of the knee in patients with anterior cruciate ligament deficiency. Hypothesis: The three-dimensional kinematics of anterior cruciate ligament-deficient knees are changed even during low-stress activities, such as walking, but can be restored by reconstruction. Study Design: Case control study. Methods: Using a three-dimensional optoelectronic gait analysis system, we examined 13 patients with anterior cruciate ligament-deficient knees, 21 patients with anterior cruciate ligament-reconstructed knees, and 10 control subjects with uninjured knees during walking. Results: Normal patterns of knee flexion-extension, abduction-adduction, and internal-external rotation during the gait cycle were maintained by all subjects. A significant difference in tibial rotation angle during the initial swing phase was found in anterior cruciate ligament-deficient knees compared with reconstructed and control knees. The patients with anterior cruciate ligament-deficient knees rotated the tibia internally during the initial swing phase, whereas the others rotated externally. Conclusions: Patients with anterior cruciate ligament-deficient knees experienced repeated episodes of rotational instability during walking, whereas patients with reconstruction experienced tibial rotation that is closer to normal. Clinical Relevance: Repeated episodes of knee rotational instability may play a role in the development of pathologic knee conditions
Conceptualising a Dynamic Technology Practice in Education Using Argyris and Schön's Theory of Action
Despite substantial national effort to integrate technology in education, it seems that practitioners in the education system are not working in line with the given policy. Evidence from large-scale studies of students’ technology practices at school over the last decade show disparities in student practices. The observed gap between the micro and the macro level call for a closer exploration. Research that explores the influence of social and organizational factors may be useful for understanding the processes behind such gaps. Argyris and Schön’s ‘Theory of Action’ (1978) is proposed as an example of an organizational theory that can be adopted in educational technology research to move towards understanding the complexities of technology practice. To encourage discourse and application of Argyris and Schön’s theory in the field of educational technology research, this paper introduces the theory, a review of its empirical application in research of teacher educations’ technology practice and relevant conceptual work. The paper presents a conceptual framework based on Argyris and Schön’s theory that has been developed through two recent studies, and invites its application in future research and development
Digital transformation in learning organizations
This concluding chapter takes a summarizing look at the contributions of the anthology, guided by two overarching questions: What dimensions are involved in the digital transformation of learning organizations? Which design perspectives can be used for digital transformation in learning organizations? In conclusion, this chapter leads back to the starting point of the anthology: the project #ko.vernetzt and the question of what significance the dimensions and design perspectives of digital transformation have in learning organizations
Learning Agility: Many Questions, a Few Answers, and a Path Forward
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/92383/1/j.1754-9434.2012.01465.x.pd
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