Homotopy type of spaces of curves with constrained curvature on flat surfaces

Let $S$ be a complete flat surface, such as the Euclidean plane. We determine the homeomorphism class of the space of all curves on $S$ which start and end at given points in given directions and whose curvatures are constrained to lie in a given open interval, in terms of all parameters involved. Any connected component of such a space is either contractible or homotopy equivalent to an $n$-sphere, and every $n\geq 1$ is realizable. Explicit homotopy equivalences between the components and the corresponding spheres are constructed.Comment: 39 pages, 13 figures. Differs from previous version by many improvements of the expositio

Challenges and opportunities in paediatric cardiac services: Time for action

The 6th World Congress of Paediatric Cardiology and Cardiac Surgery recently held in Cape Town attracted over 3 000 registered delegates, the vast majority of which were scientific attendees. This congress, hosted by the South African Heart Association and organised by the Paediatric Cardiac Society of South Africa, highlighted the needs of children and adults with highly complex congenital cardiac lesions as well as those with acquired preventable disease such as rheumatic heart disease and noncommunicable cardiovascular diseases with their origins in childhood. The scientific programme addressedthe most recent advances in paediatric cardiac disease and reflected new developments in treatment, diagnosis and management while constantly reminding delegates of inadequacies, inequalities and health system concerns affecting patient care

Transform Learning - Registration of medical images using self organization

A network model is introduced that allows a multimodal registration of two images. It can be used for a image-model or a model-model registration. The application of the network to registering tomographic to 3D ultrasonic data is introduced. Results on artificial and real ultrasound image data sets are discussed

Computer-assisted auscultation as a screening tool for cardiovascular disease : a cross-sectional study

Includes synopsis.Includes bibliographical references.Cardiac auscultation is inherently qualitative, highly subjective and requires considerable skill and experience. Computer- assisted auscultation (CAA) is an objective referral-decision support tool that aims to minimise inappropriate referrals. This study evaluated the sensitivity and specificity of 2 CAA systems, Cardioscan® and Sensi®, in detecting echo-confirmed cardiac abnormalities in 79 consecutive patients referred for assessment to a tertiary cardiac clinic. CAA demonstrated suboptimal sensitivity and specificity in detecting cardiac abnormalities in children and adults. As both systems demonstrate 100% sensitivity in detecting acyanotic heart disease, and theoretically carry significant potential in resource-limited settings, further development of current technologies to improve sensitivity and specificity for clinical applications is still warranted