Precision biomechanical motion tracking and throw characterisation in professional darts

In professional sports there are in general three steps required to improve performance namely task definition, training and performance assessment. This process is iteratively repeated and feedback generated from quantitative performance measurement is in turn used for task redefinition. Task definition can be achieved in a number of ways including via video streaming or indeed and as is more common, by listening to coaching staff. However non-subjective performance evaluation is difficult due to the complexity of the movements involved. When considering the subset of sports where precision accuracy and repeatability are a necessity this problem becomes inherently more difficult to solve. Until recently sports such as martial arts, fencing and darts, where the smallest deviation from a prescribed movement goal can result in large outcome error, were deemed too difficult to characterise fully. Advances in technology, as illustrated by this study, now make this type of physiometry possible.

Mapping the gene for autosomal dominant restless legs syndrome in an Irish family

Restless Legs Syndrome (RLS) is a common neurological disorder affecting nearly 15% of the general population. Ironically, RLS can be described as the most common condition one has never heard of. It is usually characterised by uncomfortable, unpleasant sensations in the lower limbs inducing an uncontrollable desire to move the legs. RLS exhibits a circadian pattern with symptoms present predominantly in the evening or at night, thus leading to sleep disruption and daytime somnolence. RLS is generally classified into primary (idiopathic) and secondary (symptomatic) forms. Primary RLS includes sporadic and familial cases of which the age of onset is usually less than 45 years and progresses slowly with a female to male ratio of 2:1. Secondary forms often occur as a complication of another health condition, such as iron deficiency or thyroid dysfunction. The age of onset is usually over 45 years, with an equal male to female ratio and more rapid progression. Ekbom described the familial component of the disorder in 1945 and since then many studies have been published on the familial forms of the disorder. Molecular genetic studies have so far identified ten loci (5q, 12q, 14p, 9p, 20p, 16p, 19p, 4q, 17p). No specific gene within these loci has been identified thus far. Association mapping has highlighted a further five areas of interest. RLS6 has been found to be associated with SNPs in the BTBD9 gene. Four other variants were found within intronic and intergenic regions of MEIS1, MAP2K5/LBXCOR1, PTPRD and NOS1. The pathophysiology of RLS is complex and remains to be fully elucidated. Conditions associated with secondary RLS, such as pregnancy or end-stage renal disease, are characterised by iron deficiency, which suggests that disturbed iron homeostasis plays a role. Dopaminergic dysfunction in subcortical systems also appears to play a central role. An ongoing study within the Department of Pathology (University College Cork) is investigating the genetic characteristics of RLS in Irish families. A three generation RLS pedigree RLS3002 consisting of 11 affected and 7 unaffected living family members was recruited. The family had been examined for four of the known loci (5q, 12q, 14p and 9p) (Abdulrahim 2008). The aim of this study was to continue examining this Irish RLS pedigree for possible linkage to the previously described loci and associated regions. Using informative microsatellite markers linkage was excluded to the loci on 5q, 12q, 14p, 9p, 20p, 16p, 19p, 4q, 17p and also within the regions reported to be associated with RLS. This suggested the presence of a new unidentified locus. A genome-wide scan was performed using two microsatellite marker screening sets (Research Genetics Inc. Mapping set and the Applied Biosystems Linkage mapping set version 2.5). Linkage analysis was conducted under an autosomal dominant model with a penetrance of 95% and an allele frequency of 0.01. A maximum LOD score of 3.59 at θ=0.00 for marker D19S878 indicated significant linkage on chromosome 19p. Haplotype analysis defined a genetic region of 6.57 cM on chromosome 19p13.3, corresponding to 2.5 Mb. There are approximately 100 genes annotated within the critical region. Sequencing of two candidate genes, KLF16 and GAMT, selected on the assumed pathophysiology of RLS, did not identify any sequence variant. This study provides evidence of a novel RLS locus in an Irish pedigree, thus supporting the picture of RLS as a genetically heterogeneous trait.

Rallying to a cause: the plays of Zakes Mda 1979-1989

Zakes Mda, dubbed one of South Africa's most prolific playwrights, produced his richest and most powerful theatre work during the 70s and 80s. Ironically, it is only in the 90s that he has been acknowledged in his own country as one of its foremost dramatists - ironic since he has recently moved away from drama into the realms of fiction. Fortunately Mda has accumulated a worthy canon of dramatic works, spanning radio and film, as well as theatre, and there is no reason to believe that he will not return to play writing. Mda has worked extensively in theatre in various capacities but most notably in the area of theatre-for-development. For example, he worked as director with Maratholi Travelling Theatre in Lesotho, an experience which contributed, in part, towards his book "When People Play People: Development Communication Through Theatre". Mda's plays have been produced in the United States, Britain, Spain, France and Russia as well as in southern Africa. "The Nun's Romantic Story" has been translated into Castilian and Catalan and "We Shall Sing for the Fatherland" and "Dark Voices Ring" have both been translated into Russian and French. In South Africa he won the Merit Award of the Amstel Playwright of the Year Society for "We Shall Sing for the Fatherland" in 1978 and in 1979 he was Amstel Playright of the Year for "The Hill". For his novel "She Plays with the Darkness", he won the Sanlam Literary Award in 1995.

Who pays and who plays? Mapping the discourse of publicly funded instrumental music education in Ireland

Instrumental music education is provided as an extra-curricular activity on a fee-paying basis by a small number of Education and Training Boards, formerly Vocational Education Committees (ETB/VECs) through specialist instrumental Music Services. Although all citizens’ taxes fund the public music provision, participation in instrumental music during school-going years is predominantly accessed by middle class families. A series of semistructured interviews sought to access the perceptions and beliefs of instrumental music education practitioners (N=14) in seven publicly-funded music services in Ireland. Canonical dispositions were interrogated and emergent themes were coded and analysed in a process of Grounded theory. The study draws on Foucault’s conception of discourse as a lens with which to map professional practices, and utilises Bourdieu’s analysis of the reproduction of social advantage to examine cultural assumptions, which may serve to privilege middle-class cultural choice to the exclusion of other social groups. Study findings show that within the Music Services, aesthetic and pedagogic discourses of the 19th century Conservatory system exert a hegemonic influence over policy and practice. An enduring ‘examination culture’ located within the Western art music tradition determines pedagogy, musical genre, and assessment procedures. Ideologies of musical taste and value reinforce the more tangible boundaries of fee-payment and restricted availability as barriers to access. Practitioners are aware of a status duality whereby instrumental teachers working as visiting specialists in primary schools experience a conflict between specialist and generalist educational aims. Nevertheless, study participants consistently advocated siting the point of access to instrumental music education in the primary schools as the most equitable means of access to instrumental music education. This study addresses a ‘knowledge gap’ in the sociology of music education in Ireland. It provides a framework for rethinking instrumental music education as equitable in-school musical participation. The conclusions of the study suggest starting-points for further educational research and may provide key ‘prompts’ for curriculum planning.

Improved kinematic sensing for motion control applications

New compensation methods are presented that can greatly reduce the slit errors (i.e. transition location errors) and interval errors induced due to non-idealities in optical incremental encoders (square-wave). An M/T-type, constant sample-time digital tachometer (CSDT) is selected for measuring the velocity of the sensor drives. Using this data, three encoder compensation techniques (two pseudoinverse based methods and an iterative method) are presented that improve velocity measurement accuracy. The methods do not require precise knowledge of shaft velocity. During the initial learning stage of the compensation algorithm (possibly performed in-situ), slit errors/interval errors are calculated through pseudoinversebased solutions of simple approximate linear equations, which can provide fast solutions, or an iterative method that requires very little memory storage. Subsequent operation of the motion system utilizes adjusted slit positions for more accurate velocity calculation. In the theoretical analysis of the compensation of encoder errors, encoder error sources such as random electrical noise and error in estimated reference velocity are considered. Initially, the proposed learning compensation techniques are validated by implementing the algorithms in MATLAB software, showing a 95% to 99% improvement in velocity measurement. However, it is also observed that the efficiency of the algorithm decreases with the higher presence of non-repetitive random noise and/or with the errors in reference velocity calculations. The performance improvement in velocity measurement is also demonstrated experimentally using motor-drive systems, each of which includes a field-programmable gate array (FPGA) for CSDT counting/timing purposes, and a digital-signal-processor (DSP). Results from open-loop velocity measurement and closed-loop servocontrol applications, on three optical incremental square-wave encoders and two motor drives, are compiled. While implementing these algorithms experimentally on different drives (with and without a flywheel) and on encoders of different resolutions, slit error reductions of 60% to 86% are obtained (typically approximately 80%).