Validity and reliability of GPS for measuring instantaneous velocity during acceleration, deceleration, and constant motion

In this study, we assessed the validity and reliability of 5 and 10 Hz global positioning systems (GPS) for measuring instantaneous velocity during acceleration, deceleration, and constant velocity while straight-line running. Three participants performed 80 running trials while wearing two GPS units each (5 Hz, V2.0 and 10 Hz, V4.0; MinimaxX, Catapult Innovations, Scoresby, VIC, Australia). The criterion measure used to assess GPS validity was instantaneous velocity recorded using a tripod-mounted laser. Validity was established using the standard error of the estimate (± 90% confidence limits). Reliability was determined using typical error (± 90% confidence limits, expressed as coefficient of variation) and Pearson's correlation. The 10 Hz GPS devices were two to three times more accurate than the 5 Hz devices when compared with a criterion value for instantaneous velocity during tasks completed at a range of velocities (coefficient of variation 3.1-11.3%). Similarly, the 10 Hz GPS units were up to six-fold more reliable for measuring instantaneous velocity than the 5 Hz units (coefficient of variation 1.9-6.0%). Newer GPS may provide an acceptable tool for the measurement of constant velocity, acceleration, and deceleration during straight-line running and have sufficient sensitivity for detecting changes in performance in team sport. However, researchers must account for the inherent match-to-match variation reported when using these devices.     

Incorporating Aspects of Information Use into Relevance Feedback

In this paper we look at some of the problems in interacting with best-match retrieval systems. In particular, we examine the areas of interaction, some investigations of the complexity and breadth of interaction and attempts to categorise user's information seeking behaviour. We suggest that one of the difficulties of traditional IR systems in supporting information seeking is the way the information content of documents is represented. We discuss an alternative representation, based on how information is used within documents.     

Physiological and metabolic responses of wheelchair athletes in different racing classes to prolonged exercise

The aims of this study were to examine and compare selected physiological and metabolic responses of wheelchair athletes in two paraplegic racing classes [T3: n = 8 (lesion levels T1-T7; paraplegics); T4: n = 9 (lesion levels below T7; paraplegics)] to prolonged exercise. In addition, we describe the responses of three tetraplegic athletes [T2: n = 3 (lesion levels C6/C7: tetraplegics)]. Twenty athletes completed 90 min of exercise at 75% VO2peak on a motorized treadmill adapted for wheelchairs. The mean (+/- s) heart rates of the T3 and T4 racing classes were 165 +/- 2 and 172 +/- 6 beats.min-1, respectively. For the T4 racing class, heart rate gradually increased during the test (P < 0.05), whereas for the T3 racing class, heart rate reached a plateau after an initial increase. The mean heart rate of the tetraplegics was 114 +/- 3 beats.min-1. The T3 and T4 classes exhibited similar respiratory exchange ratios, plasma lactate and glucose concentrations throughout the test. For both the T3 and T4 racing class, free fatty acid, glycerol, ammonia, urea and potassium concentrations had increased from resting values by the end of the test (P < 0.05). In conclusion, the results of this study suggest that endurance-trained wheelchair athletes are able to maintain velocities equivalent to the same relative exercise intensity (75% VO2peak) for prolonged periods irrespective of lesion level.     

The Prosocial and Antisocial Behaviour in Sport Scale: Further evidence for construct validity and reliability

Abstract

The purpose of this research was to provide further evidence for the construct validity (i.e., convergent, concurrent, and discriminant validity) of the Prosocial and Antisocial Behaviour in Sport Scale (PABSS), an instrument that has four subscales measuring prosocial and antisocial behaviour toward teammates and opponents. We also investigated test-retest reliability and stability of the PABSS. We conducted three studies using athletes from a variety of team sports. In Study 1, participants (N = 129) completed the PABSS and measures of physical and verbal aggression, hostility, anger, moral identity, and empathy; a sub-sample (n = 111) also completed the PABSS one week later. In Study 2, in addition to the PABSS, participants (N = 89) completed measures of competitive aggressiveness and anger, moral attitudes, moral disengagement, goal orientation, and anxiety. In Study 3, participants (N = 307) completed the PABSS and a measure of social goals. Across the three studies, the four subscales evidenced the hypothesised relationships with a number of variables. Correlations were large between the two antisocial behaviours and small between the two prosocial behaviours. Overall, the findings supported the convergent, concurrent, and discriminant validity of the scale, provided evidence for its test-retest reliability and stability, and suggest that the instrument is a valid and reliable measure of prosocial and antisocial behaviour in sport.     

E.E. Fournier d’Albe’s Fin de siècle: Science,Nationalism and Monistic Philosophy in Britain and Ireland

The fin de siècle witnessed radical shifts in the intellectual and cultural landscapes of the British Isles in the context of a general revolt against Victorian values. E. E. Fournier d’Albe – physicist, spiritualist, inventor and Pan-Celticist – personified the ability of intellectuals to latch onto and advance new trends, made available by the emergent intellectual pluralism. Like many contemporaries he rejected traditional religion, but he also disdained scientific materialism, and sought a deeper metaphysical meaning to life, pursued through his various interests. Influenced by the totalising theories of figures like Herbert Spencer and Ernst Haeckel, Fournier concocted his own brand of scientific monism, rejecting materialism, embracing spiritualism, and ever optimistic in the notion of scientific progress, even in the wake of the carnage of the Great War. The article aims to give Fournier a fuller historical treatment, allowing his story to add to understanding of the milieus in which he lived and operated, and revealing how his monistic philosophy incorporated some of the disparate cultural strands explored by intellectuals in the fin de siècle reaction against conventional Victorian ideals.     

Text as design, writers as designers

Acknowledging the changing nature of writing in the 21st century, particularly the increasing significance of visual characteristics in written texts, this paper explores the implications of multimodality for the pedagogy of writing. It considers the potential disjunction between children's life experiences of written texts and the demands of the writing curriculum, particularly in the secondary phase, and whilst arguing for greater recognition of the role of the visual, the paper also notes the importance of ensuring all children also have access to powerful verbal texts. Drawing on two separate research studies, the paper demonstrates how visual characteristics of written texts influence readers' responses to texts, but also how writers are aware of some of the choices they make in shaping verbal texts. The paper argues for a reconceptualisation of the writing process as a design process, and for a pedagogy of writing which encourages, supports and enables writers to become confident and effective designers of texts.     

Are academic outcomes of higher education provision relevant to and deliverable in the workplace setting?

Current developments in higher education strongly indicate that the way ahead in many disciplines is much closer co-operation between academia and industry. There is growing demand that recognition should be given to learning, irrespective of the environment in which it occurs.This article reflects on what are deemed to be essential components of a degree, and considers how they might be transformed into forms suitable for demonstration in the work environment. The discussion is supported by findings of a survey carried out in conjunction with a development - Structured Industrial Practice Studies - which integrates academic learning and learning in the work environment for full-time students. The findings, however, are of relevance beyond the particular model of learning and mode of attendance. There appears to be potential for achieving in the workplace aspects of courses which, in recent times, have been the prerogative of higher education establishments. However, such potential is variable between working environments and is dependent on higher education providers adapting to different structures in delivery.     

Size-dependent trajectories of DNA macromolecules due to insulative dielectrophoresis in submicrometer-deep fluidic channels

In this paper, we demonstrate for the first time that insulative dielectrophoresis can induce size-dependent trajectories of DNA macromolecules. We experimentally use λ (48.5 kbp) and T4GT7 (165.6 kbp) DNA molecules flowing continuously around a sharp corner inside fluidic channels with a depth of 0.4 μm. Numerical simulation of the electrokinetic force distribution inside the channels is in qualitative agreement with our experimentally observed trajectories. We discuss a possible physical mechanism for the DNA polarization and dielectrophoresis inside confining channels, based on the observed dielectrophoresis responses due to different DNA sizes and various electric fields applied between the inlet and the outlet. The proposed physical mechanism indicates that further extensive investigations, both theoretically and experimentally, would be very useful to better elucidate the forces involved at DNA dielectrophoresis. When applied for size-based sorting of DNA molecules, our sorting method offers two major advantages compared to earlier attempts with insulative dielectrophoresis: Its continuous operation allows for high-throughput analysis, and it only requires electric field strengths as low as ∼10 V∕cm.     

Evaluating epistemic uncertainty under incomplete assessments

The thesis of this study is to propose an extended methodology for laboratory based Information Retrieval evaluation under incomplete relevance assessments. This new methodology aims to identify potential uncertainty during system comparison that may result from incompleteness. The adoption of this methodology is advantageous, because the detection of epistemic uncertainty – the amount of knowledge (or ignorance) we have about the estimate of a system’s performance – during the evaluation process can guide and direct researchers when evaluating new systems over existing and future test collections. Across a series of experiments we demonstrate how this methodology can lead towards a finer grained analysis of systems. In particular, we show through experimentation how the current practice in Information Retrieval evaluation of using a measurement depth larger than the pooling depth increases uncertainty during system comparison.