Teaching Threshold Concepts in Virtual Reality: Exploring the Conceptual Requirements for Systems Design.

In a complex world students need to be equipping with a range of capabilities that will enable them to be critical and flexible learners and citizens. The central research objective in this paper is to explore the argument that virtual reality (VR) technologies, collaborative learning approaches and recognition of the values and importance of thresholds to learning are components that can equip students in and for the future. Threshold concepts are specific concepts which are identified as essential in the acquisition of thinking, learning and communication of understanding within a specific subject of learning. Threshold experiences occur when learners identify moments of “learning leaps” which are cognitive transformations or changes in conceptual role for the learner, enabling them to work at higher levels of abstraction and creativity. Virtual reality technology is increasingly applied in education and can be used to test multiple threshold concepts and applied to open problems that allow for low-stress and real-time interactions as well as supporting collaborative groups with rapid interactions. Applications built on VR can engage, immerse, and guide learners in ways not yet undertaken in the education of threshold concepts. Through literature review we explore the definitions of threshold concepts, VR technologies, and the opportunities for teaching threshold concepts using VR technologies. We additionally predict possible limitations of the technologies. Further, we propose a systems design approach as informed by our literature review

New-onset pain in the early phase and three months following stroke – data from a multicenter study

Martina Reiten Bovim,1 Bent Indredavik,1,2 Anne Hokstad,1,2 Stian Lydersen,3 Torunn Askim1,2 1Department of Neuromedicine and Movement Science, Norwegian University of Science and Technology (NTNU), Trondheim, Norway; 2Stroke Unit, St. Olavs Hospital, Trondheim, Norway; 3Regional Centre for Child and Youth Mental Health and Child Welfare, Department of Mental Health, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology (NTNU), Trondheim, Norway Background: The reported prevalence of pain after stroke varies considerably, depending on how pain is measured, time after stroke, and characteristics of the selected population. The aims of this study were to investigate the prevalence and distribution of new-onset pain initially and three months after stroke in a general Norwegian cohort, and to examine whether symptoms of anxiety or depression were associated with new-onset pain after stroke. Material and methods: Stroke patients were included from eleven different hospitals within 14 days after stroke onset. Pain was assessed at inclusion and three months after stroke, and the distribution of pain was marked on a body map. New-onset pain was defined as pain reported by the patients to have occurred after the stroke. Symptoms of anxiety and depression were evaluated using the Hospital Anxiety and Depression Scale. Results: A total of 390 patients were included. Pain data were available in 142 patients at both inclusion and follow-up, while 245 patients had available data for the regression analysis. In patients with follow-up data, new-onset pain occurred in 14 (9.9%) patients at inclusion and in 31 (21.8%) patients three months later, P=0.005. New-onset pain in the affected upper limb and bilaterally in the lower limbs was more common at three months than initially after stroke. Symptoms of anxiety were associated with new-onset pain (OR=1.13, 95% CI 1.01–1.27, P=0.030). Conclusion: This study shows that new-onset pain occurs in one out of ten patients initially after stroke and in one out of five patients three months after stroke, and it was associated with symptoms of anxiety. This raises the question of whether easing symptoms of anxiety might help to prevent or treat new pain after stroke. Keywords: stroke, pain, cerebral infarction, complication, anxiet

Preliminary Results on a Simple Approach to G/G/c-like Queues

In this paper we consider a multi-server queue with a near general arrival process (represented as an arbitrary state-dependent Coxian distribution), a near general state-dependent Coxian service time distribution and a possibly finite queueing room. In addition to the dependence on the current number of customers in the system, the rate of arrivals and the progress of the service may depend on each other. We propose a semi-numerical method based on the use of conditional probabilities to compute the steady-state queue length distribution in such a queueing system. Our approach is conceptually simple, easy to implement and can be applied to both infinite and finite Cm/Ck/c-like queues. The proposed method uses a simple fixed-point iteration. In the case of infinite queues, it avoids the need for arbitrary truncation through the use of asymptotic conditional probabilities. This preliminary study examines the computational behavior of the proposed method with a Cox-2 service distribution. Our results indicate that it is robust and performs well even when the number of servers and the coefficient of variation of the service times are relatively high. The number of iterations to attain convergence varies from low tens to several thousand. For example, we are able to solve queues with 1024 servers and the coefficients of variation of the service time and of the time between arrivals set to 4 within 1100 iterations