This paper presents the first steps towards a new type of pedagogical agent – a Challenger Teachable Agent, CTA. The overall aim of introducing a CTA is to increase engagement and motivation and challenge students into deeper learning and metacognitive reasoning. The paper discusses desired design features of such an agent on the basis of related work and results from a study where 11-year old ...

This chapter presents an overview of the current state of cognitive task analysis (CTA) in research and practice. CTA uses a variety of interview and observation strategies to capture a description of the explicit and implicit knowledge that experts use to perform complex tasks. The captured knowledge is most often transferred to training or the development of expert systems. The first section ...

Hemispherectomy is an established neurosurgical procedure for unilateral refractory epilepsy . Even though the surgical approach has evolved greatly, prevention of catastrophic intraoperative bleeding is a challenge. It is important that surgeons know the abnormal blood vessel before surgery. Herein, we report our experience with two patients in whom computed tomographic angiography (CTA) was u...

Published as: Clark, R. E. and Estes, F. (1996)Cognitive task analysis, International Journal of Educational Research. 25(5). 403-417. Abstract Two factors have made behaviorally-based task analysis training systems obsolete: 1) these systems cannot describe the complex knowledge required of European and North American workers by recent changes in the global economy, and 2) recent research in c...

OBJECTIVES This review aims to establish the impact on conventional angiography and endovascular intervention of contrast-enhanced magnetic resonance angiography (CE-MRA) and contrast-enhanced computed tomography angiography (CE-CTA) on a background of evolving technology, changing clinical requirements and resulting clinical repercussions. METHODS The angiographic and interventional caseload...

BACKGROUND AND PURPOSE The computed tomography angiography (CTA) spot sign is a validated biomarker for poor outcome and hematoma expansion in intracerebral hemorrhage. The spot sign has proven to be a dynamic entity, with multimodal imaging proving to be of additional value. We investigated whether the addition of a 90-second delayed CTA acquisition would capture additional intracerebral hemor...

In this communication, we studied whether 3D-CT angiography (3D CTA) gives us enough information for a safe operation without those from conventional catheter angiography (CCA) in patients with ruptured aneurysms. Between December 1996 and September 2005, we treated 162 consecutive patients with ruptured aneurysms in the acute stage based on 3D-CTA findings. One hundred sixty-two ruptured aneur...

BACKGROUND Multidetector computed tomography coronary angiography (CTA) is a robust method for the noninvasive diagnosis of coronary artery disease. However, in its current form, CTA is limited in its prediction of myocardial ischemia. The purpose of this study was to test whether adenosine stress computed tomography myocardial perfusion imaging (CTP), when added to CTA, can predict perfusion a...

Multiple myeloma (MM) stem cells, proposed to be responsible for the tumourigenesis, drug resistance and recurrence of this disease, are enriched in the cancer stem cell-like side population (SP). Cancer testis antigens (CTA) are attractive targets for immunotherapy because they are widely expressed in cancers but only in limited types of normal tissues. We designed a high throughput assay, whi...

BACKGROUND The purpose of this study was to determine the prognostic value of computed tomography coronary angiography (CTA)-derived left ventricular (LV) function analysis and to assess its incremental prognostic value over the detection of significant stenosis using CTA. METHODS In 728 patients (400 males, mean age 55 ± 12 years) with known or suspected CAD, the presence of significant sten...