Effects of visual occlusion and fatigue on motor performance in water

The purpose of this study was to test the effects of visual occlusion and fatigue on the motor performance of vertical skills in synchronized swimming. Experienced synchronized swimmers (n = 12) were randomly assigned to either an exercise or nonexercise (control) activity group. Subjective ratings of fatigue were obtained from the swimmers who then each performed four vertical skills under alternating conditions of vision and visual occlusion before and after either a swimming (designed to induce fatigue) or nonphysical activity. A main effect of activity (p < .03) was found for two measures of performance accuracy (lateral and anterior total distance traveled) but not for lateral and anterior maximum deviation from vertical, indicating that fatigue played a role in executing the skills. The data also indicate that the maintenance of a stationary position is a skill of greater difficulty than maintaining a true vertical. In contrast with previous research findings on synchronized swimmers, a significant effect of vision in all conditions was found, with performance decrements in the conditions of visual occlusion showing that vision provided important sensory input for the swimmers.

Item validity of the physical demands from the Dictionary of Occupational Titles for the functional capacity evaluation of clients with chronic back pain

This study assessed the item validity of 15 of the physical demands from the Dictionary of Occupational Titles (DOT), as evaluated in a new approach to functional capacity evaluation (FCE) for clients with chronic back pain, the Gibson Approach to FCE (GAPP FCE). Fifty-two occupational therapists were sent the specifications of the items in the GAPP FCE procedures and were asked to rate the items in terms of item-objective congruence, relevance and difficulty. A response rate of 59.2% was obtained. The majority of the therapists agreed that most of the items were congruent with the objectives based on the definition of the physical demands from the DOT. The items evaluating Balancing and Pushing and Pulling had the lowest item-objective congruence. The evaluation of Balancing and the Lifting, Carrying and Pushing and Pulling of loads greater than light-medium weight (10–16 kg) were not considered significantly relevant. Concerns were raised about the difficulty and safety of the evaluation of Lifting, Carrying and Pushing and Pulling with clients with chronic back pain, particularly if the therapist evaluates the manual handling of medium to heavy loads. These results may have implications for other FCEs, particularly those which are based on the DOT, or when assessing clients with chronic back pain.

The influence of bovine colostrum supplementation on exercise performance in highly trained cyclists

Purpose: The aim of this experiment was to investigate the influence of low dose bovine colostrum supplementation on exercise performance in cyclists over a 10 week period that included 5 days of high intensity training (HIT). Methods: Over 7 days of preliminary testing, 29 highly trained male road cyclists completed a VO2max test (in which their ventilatory threshold was estimated), a time to fatigue test at 110% of ventilatory threshold, and a 40 km time trial (TT40). Cyclists were then assigned to either a supplement (n = 14, 10 g/day bovine colostrum protein concentrate (CPC)) or a placebo group (n = 15, 10 g/day whey protein) and resumed their normal training. Following 5 weeks of supplementation, the cyclists returned to the laboratory to complete a second series of performance testing (week 7). They then underwent five consecutive days of HIT (week 8) followed by a further series of performance tests (week 9). Results: The influence of bovine CPC on TT40 performance during normal training was unclear (week 7: 1+/-3.1%, week 9: 0.1+/-2.1%; mean+/-90% confidence limits). However, at the end of the HIT period, bovine CPC supplementation, compared to the placebo, elicited a 1.9+/-2.2% improvement from baseline in TT40 performance and a 2.3+/-6.0% increase in time trial intensity (% VO2max), and maintained TT40 heart rate (2.5+/-3.7%). In addition, bovine CPC supplementation prevented a decrease in ventilatory threshold following the HIT period (4.6+/-4.6%). Conclusion: Low dose bovine CPC supplementation elicited improvements in TT40 performance during an HIT period and maintained ventilatory threshold following five consecutive days of HIT.

Transformational leadership within virtual teams: Examining the mediating influence of trust and role clarity for performance and knowledge sharing

Virtual teams differ from tradidonal, co-located teams in that they primarily communicate via informadon technolog}' such as email, video conferencing and web based coUaboradve environments rather than in a face-to-face medium. There has been a lack of empirical research into the influence that leadership has within virtual teams upon key outcomes such as performance and knowledge sharing. This paper examines antecedents of knowledge sharing and performance, namely role clarit)' and trust in a team leader. We predicted that transformadonal leadership would posidvely influence both performance and knowledge sharing within virtual teams. We also h^'pothesised that trust in a leader and role clarit)' would mediate both the associadon between transformadonal leadership and performance as well as the associadon between transformadonal leadership and knowledge sharing within virtual teams. Data was collected from a public sector organisadon using virtual teams, Pardcipants responded to a self-report quesdonnaire. Supervisor radngs of performance and knowledge sharing were also obtained. In general we found support for a posidve reladonship between transformadonal leadership and performance and knowledge sharing within virtual teams. Using mediated muldple regression, we found support for the mediadng role of trust in the leader and role clarit}' between transformadonal leadership and performance and knowledge sharing. Implicadons of the results are provided.

The moderating effects of goal orientations on reactions to goal-performance discrepancies

Due to the growing popularity of goal setting programs within organisations, an understanding of the mechanisms underlying the dynamic regulation of performance is paramount (Williams, Donovan, & Dodge, 2000). Goals serve as standards or referents by which behaviour is directed and evaluated. Whilst their importance is well established in the existing literature (e.g. Locke & Latham, 1990), more recent research has highlighted the potential importance of goal-performance discrepancies. Moreover, the relationship between goal-performance discrepancies and outcomes such as self-efficacy and personal goals appears to vary between people (Schmidt & Chambers, 2002). Of interest in the current study was how these relationships were impacted by goal orientation. Ninety-seven participants completed 30 two-minute trials of an Air Traffic Control task. Task specific goal orientation was measured prior to commencement of the task and measures of self-efficacy and personal task goals were taken at each trial to assess the within-person relationships between goal performance discrepancies and each of these dependant variables, as well as the moderating effects of goal orientations on these relationships. Analysis supported the existence of a positive relationship between goal-performance discrepancies and outcome variables, with performance-approach and –avoidance orientations significantly moderating these associations. Implications and future directions are discussed.

Relationships between quality of experience and participation in diverse performance settingshttp://espace.library.uq.edu.au/workflow/edit_metadata.php?id=382160&wfs_id=778

The flow concept describes a model of enjoyment that has relevance for understanding participation and experience across a wide range of activities (Csikszentmihalyi, 1997). The basic premise of the flow concept is that when challenges and skills are simultaneously balanced and extending the individual, a state of total absorption can occur. Research by Jackson and colleagues has examined the utility of the flow concept to understanding participation and performance in sport settings. Recently, Jackson and Eklund have examined flow in a range of performance settings: sport, exercise, dance, creative and performing arts, and music. In this paper, we present descriptive and construct validity data on how participants in these activities experienced flow, as assessed by the recently revised flow scales: The Dispositional Flow Scale-2 (DFS-2) and Flow State Scale-2 (FSS-2) (Jackson & Eklund, 2002). The fmdings will be discussed in relation to the utility of the flow concept to understanding participation across performance settings.

The effects of domain-specific avoid and prove goal orientations on performance: A multilevel analysis

Recently, goal orientation, a mental framework for understanding how individuals approach learning and achievement situadons, has emerged as an important predictor of performance. This study addressed the effects of domain-specific avoid and prove orientations on performance from the betweenand within-person levels of analysis. One hundred and three participants performed thirty trials of an airtraffic control task. Domain-specific avoid and prove orientations were measured before each trial to assess the effects of changes in goal orientadon on changes in performance (i.e. within-person relationships). Average levels of avoid and prove orientations were calculated to assess the effect of goal orientation on overall performance (i.e. between-person relationships). Findings from the between-person level of analysis revealed that high prove-orientated individuals performed better than low proveorientated individuals. Results also revealed that average goal orientation levels moderated the withinperson relationships. The effect of changes in avoid orientation on changes in performance was stronger for low versus high avoid-oriented individuals while the effect of changes in prove orientadon on changes in performances was stronger for low versus highprove oriented individuals. Implications of these findings are considered.

Attentional changes in pre-stimulus oscillatory activity within early visual cortex are predictive of human visual performance

Physiological and neuroimaging studies provide evidence to suggest that attentional mechanisms operating within the fronto-parietal network may exert top–down control on early visual areas, priming them for forthcoming sensory events. The believed consequence of such priming is enhanced task performance. Using the technique of magnetoencephalography (MEG), we investigated this possibility by examining whether attention-driven changes in cortical activity are correlated with performance on a line-orientation judgment task. We observed that, approximately 200 ms after a covert attentional shift towards the impending visual stimulus, the level of phase-resetting (transient neural coherence) within the calcarine significantly increased for 2–10 Hz activity. This was followed by a suppression of alpha activity (near 10 Hz) which persisted until the onset of the stimulus. The levels of phase-resetting, alpha suppression and subsequent behavioral performance varied between subjects in a systematic fashion. The magnitudes of phase-resetting and alpha-band power were negatively correlated, with high levels of coherence associated with high levels of performance. We propose that top–down attentional control mechanisms exert their initial effects within the calcarine through a phase-resetting within the 2–10 Hz band, which in turn triggers a suppression of alpha activity, priming early visual areas for incoming information and enhancing behavioral performance.

The impact of the performance measurement systems in setting the 'direction' in the University of Warwick

This paper presents a case study examining the role of performance measurement systems in setting organizational ‘direction’. There is a growing concern in the existing literature to link the development of organizational ‘direction’ with performance measurement systems. Furthermore, the alignment between organizational ‘direction’, strategy and performance measurement is an area of increasing interest for both academics and practitioners. However, there is no adequate research recorded in the literature on the use of the performance measurement systems and the potential impact that performance measurement can have in setting the organizational ‘direction’. This study reports the findings of a case study from one of the leading academic institutions in the UK, the University of Warwick, presenting the main characteristics of its performance measurement system and attempting to explain the connection with setting the university’s ‘direction’.

On the validity of subjective measures of company performance

Subjective measures of company performance are widely used in research and typically are interpreted as equivalent to objective measures. Yet, the assumption of equivalence is open to challenge. We compared the use of both types of measure in 3 separate samples. Findings were consistent in showing that: (a) subjective and objective measures of company performance were positively associated (convergent validity); (b) those relationships were stronger than those between measures of differing aspects of performance using the same method (discriminant validity); and (c) the relationships of subjective and objective company performance measures with a range of independent variables were equivalent (construct validity).

Evaluating corporate performance:a critique of economic value added

There has been a revival of interest in economic techniques to measure the value of a firm through the use of economic value added as a technique for measuring such value to shareholders. This technique, based upon the concept of economic value equating to total value, is founded upon the assumptions of classical liberal economic theory. Such techniques have been subject to criticism both from the point of view of the level of adjustment to published accounts needed to make the technique work and from the point of view of the validity of such techniques in actually measuring value in a meaningful context. This paper critiques economic value added techniques as a means of calculating changes in shareholder value, contrasting such techniques with more traditional techniques of measuring value added. It uses the company Severn Trent plc as an actual example in order to evaluate and contrast the techniques in action. The paper demonstrates discrepancies between the calculated results from using economic value added analysis and those reported using conventional accounting measures. It considers the merits of the respective techniques in explaining shareholder and managerial behaviour and the problems with using such techniques in considering the wider stakeholder concept of value. It concludes that this economic value added technique has merits when compared with traditional accounting measures of performance but that it does not provide the universal panacea claimed by its proponents.

The impacts of market orientation and corporate social responsibility on firm performance:evidence from China

Purpose – The purpose of this paper is to investigate the joint effects of market orientation (MO) and corporate social responsibility (CSR) on firm performance. Design/methodology/approach – Data were collected via a questionnaire survey of star-rated hotels in China and a total of 143 valid responses were received. The hypotheses were tested by employing structural equation modelling with a maximum likelihood estimation option. Findings – It was found that although both MO and CSR could enhance performance, once the effects of CSR are accounted for, the direct effects of MO on performance diminish considerably to almost non-existent. Although this result may be due to the fact that the research is conducted in China, a country where CSR might be crucially important to performance given the country's socialist legacy, it nonetheless provides strong evidence that MO's impact on organizational performance is mediated by CSR. Research limitations/implications – The main limitations include the use of cross-sectional data, the subjective measurement of performance and the uniqueness of the research setting (China). The findings provide an additional important insight into the processes by which a market oriented culture is transformed into superior organizational performance. Originality/value – This paper is one of the first to examine the joint effects of MO and CSR on business performance. The empirical evidence from China adds to the existing literature on the respective importance of MO and CSR.

Studies on the deactivation and reactivation of spent hydroprocessing catalyst

A study is reported on the deactivation of hydroprocessing catalysts and their reactivation by the removal of coke and metal foulants. The literature on hydrotreating catalyst deactivation by coke and metals deposition, the environmental problems associated with spent catalyst disposal, and its reactivation/rejuvenation process were reviewed. Experimental studies on catalyst deactivation involved problem analysis in industrial hydroprocessing operations, through characterization of the spent catalyst, and laboratory coking studies. A comparison was made between the characteristics of spent catalysts from fixed bed and ebullating bed residue hydroprocessing reactor units and the catalyst deactivation pattern in both types of reactor systems was examined. In the laboratory the nature of initial coke deposited on the catalyst surface and its role on catalyst deactivation were studied. The influence of initial coke on catalyst surface area and porosity was significant. Both catalyst acidity and feedstock quality had a remarkable influence on the amount and the nature of the initial coke. The hydroenitrogenation function (HDN) of the catalyst was found to be deactivated more rapidly by the initial coke than the hydrodesulphurization function (HDS). In decoking experiments, special attention was paid to the initial conditions of coke combustion, since the early stages of contact between the coke on the spent catalyst surface and the oxygen are crucial in the decoking process. An increase in initial combustion temperature above 440oC and the oxygen content of the regeneration gas above 5% vanadium led to considerable sintering of the catalyst. At temperatures above 700oC there was a substantial loss of molybdenum from the catalyst, and phase transformations in the alumina support. The preferred leaching route (coked vs decoked form of spent catalyst) and a comparison of different reagents (i.e., oxalic acid and tartaric acid) and promoters (i.e., Hydrogen Peroxide and Ferric Nitrate) for better selectivity in removing the major foulant (vanadium), characterization and performance evaluation of the treated catalysts and modelling of the leaching process were addressed in spent catalyst rejuvenation studies. The surface area and pore volume increased substantially with increasing vanadium extraction from the spent catalyst; the HDS activity showed a parallel increase. The selectivity for leaching of vanadium deposits was better, and activity recovery was higher, for catalyst rejuvenated by metal leaching prior to decoking.

The separation of hydrogen and carbon monoxide using polymer membranes

This work studies the development of polymer membranes for the separation of hydrogen and carbon monoxide from a syngas produced by the partial oxidation of natural gas. The CO product is then used for the large scale manufacture of acetic acid by reaction with methanol. A method of economic evaluation has been developed for the process as a whole and a comparison is made between separation of the H2/CO mixture by a membrane system and the conventional method of cryogenic distillation. Costs are based on bids obtained from suppliers for several different specifications for the purity of the CO fed to the acetic acid reactor. When the purity of the CO is set at that obtained by cryogenic distillation it is shown that the membrane separator offers only a marginal cost advantage. Cost parameters for the membrane separation systems have been defined in terms of effective selectivity and cost permeability. These new parameters, obtained from an analysis of the bids, are then used in a procedure which defines the optimum degree of separation and recovery of carbon monoxide for a minimum cost of manufacture of acetic acid. It is shown that a significant cost reduction is achieved with a membrane separator at the optimum process conditions. A method of "targeting" the properties of new membranes has been developed. This involves defining the properties for new (hypothetical -yet to be developed) membranes such that their use for the hydrogen/carbon monoxide separation will produce a reduced cost of acetic acid manufacture. The use of the targeting method is illustrated in the development of new membranes for the separation of hydrogen and carbon monoxide. The selection of polymeric materials for new membranes is based on molecular design methods which predict the polymer properties from the molecular groups making up the polymer molecule. Two approaches have been used. One method develops the analogy between gas solubility in liquids and that in polymers. The UNIFAC group contribution method is then used to predict gas solubility in liquids. In the second method the polymer Permachor number, developed by Salame, has been correlated with hydrogen and carbon monoxide permeabilities. These correlations are used to predict the permeabilities of gases through polymers. Materials have been tested for hydrogen and carbon monoxide permeabilities and improvements in expected economic performance have been achieved.

The evaluation of information systems in the organisational context of the National Health Service. Available in 2 volumes.

This thesis describes a project which has investigated the evaluation of information systems. The work took place in, and is related to, a specific organisational context, that of the National Health Service (NHS). It aims to increase understanding of the evaluation which takes place in the service and the way in which this is affected by the NHS environment. It also investigates the issues which surround some important types of evaluation and their use in this context. The first stage of the project was a postal survey in which respondents were asked to describe the evaluation which took place in their authorities and to give their opinions about it. This was used to give an overview of the practice of IS evaluation in the NHS and to identify its uses and the problems experienced. Three important types of evaluation were then examined in more detail by means of action research studies. One of these dealt with the selection and purchase of a large hospital information system. The study took the form of an evaluation of the procurement process, and examined the methods used and the influence of organisational factors. The other studies are concerned with post-implementation evaluation, and examine the choice of an evaluation approach as well as its application. One was an evaluation of a community health system which had been operational for some time but was of doubtful value, and suffered from a number of problems. The situation was explored by means of a study of the costs and benefits of the system. The remaining study was the initial review of a system which was used in the administration of a Breast Screening Service. The service itself was also newly operational and the relationship between the service and the system was of interest.