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Biomedical subjects

T W Whitfield

Publications and source records attributed to T W Whitfield.

7 recordsLinked to original sources

Gravitational smoothing as a global optimization strategy.

An optimization scheme for atomic cluster structures, based on exaggerating the importance of the gravitational force, is introduced. Results are presented for calculations on Lennard-Jones clusters of 13, 38, and 55 atoms, and the 13-atom Morse cluster.

Journal Article↗

Enhanced sampling in numerical path integration: an approximation for the quantum statistical density matrix based on the nonextensive thermostatistics.

Here we examine a proposed approximation for the quantum statistical density matrix motivated by the nonextensive thermostatistics of Tsallis and co-workers. The approximation involves replacing the physical potential energy with an effective one, corresponding to a generalized nonextensive statistical ensemble. We examine the convergence properties of averages calculated using the effective potential, and introduce a related method for enhanced sampling in numerical path integration. As a necessary measure, path integral energy estimators are introduced for potentials that involve explicit temperature dependence. This sampling method is found to be effective for path integral simulations involving broken ergodicity.

Journal Article↗

A multidimensional scaling analysis of the techniques that physiotherapists use.

Following the essentially 'hands-on' origin of the physiotherapy profession a century ago, the range of techniques available to practitioners has expanded considerably. While this expansion of techniques has been of research interest, the main focus has been upon individual techniques, thus neglecting the fundamental question of the use of techniques in combination. In addition, researchers have tended to treat the profession as homogeneous, thus overlooking possible differences in technique usage. The present study addressed these questions. It postulated that ordered combinations of techniques usage would be employed, and that a typology would exist that differentiates the profession according to patterns of use. The study comprised a questionnaire survey of 230 clinical physiotherapists in England. This sought information on the range and frequency of techniques used over the previous six months. Descriptive analysis indicated a high frequency of use of several techniques, notably exercise therapy, passive mobilisation techniques and ultrasound. A feature of the analysis was the use of two multivariate procedures, multidimensional scalogram analysis (MSA) and smallest space analysis (SSA). The SSAs revealed a clear structure concerning combinations of techniques used, and the MSAs provided a coherent typology based upon this usage. One feature of the techniques in combination that emerged was the frequent use of passive mobilising techniques, which was associated with equally frequent use of electrotherapy techniques. In contrast, respondents who employed neurological or respiratory techniques made little use of electrotherapy. Regarding the typology, differentiation of the profession according to use of particular combinations of techniques indicated probable specialisms. The specialist areas identified were neurological physiotherapy, respiratory physiotherapy and musculo-skeletal physiotherapy. The results reinforce the need for both future research and physiotherapy education to address the issue of techniques in combination. Finally, and on the basis of the analyses, elements of a theoretical model are advanced that may provide directions for future research.

England↗

Physiotherapists' use of evidence based practice: a cross-national study.

This study investigated clinical physiotherapists' reasons for their use of treatment techniques, with a particular focus on their utilisation of journal review and research literature. A questionnaire was completed by 180 physiotherapists in England and 141 physiotherapists in Australia. Despite the greater prevalence of pre-registration degree respondents in Australia, there were no differences between the two national groups in their reasons given for choice of treatment techniques. The basis of over 90% of each groups choice of techniques reflected what was taught during their initial training. Experience of treatment effects on prior patients, and information gained in practice-related courses, were also primary reasons. Research literature ranked least in importance as a basis for choosing techniques, and review articles fared little better. The results indicated that these physiotherapists relied mainly on information gained from formal pre- and post-registration courses. By implication, the most obvious means of influencing physiotherapists' attitudes to research utilisation lies with those responsible for physiotherapy education.

Attitude of Health Personnel↗

Salient features of Munsell colour space as a function of monolexemic naming and response latencies.

This study provides a replication of Boynton and Olson's (1990) work (Vision Research, 30, pp. 1311-1317), but using a more extensive model of colour space--Munsell as distinct from OSA-UCS. It involved 20 subjects in a total of 17,840 observations of 446 colours, in which monolexemic naming and response times were recorded. The results clearly differentiate between basic and non,basic colour categories using measures of consistency, consensus and response time. While the results are equivocal in distinguishing between the so-called "landmark" and "other basic colours", they are unequivocal in confirming the salience of the eleven basic colour categories initially proposed by Berlin and Kay [(1969) Basic colour terms: their universality and evolution, Berkeley, CA: University of California Press], and, in so doing, reinforce their perceptual significance and probable physiological basis. The results also reveal differences in non-basic colour naming that further confirm the special status of the basic colour categories and their role in categorical colour perception.

Adolescent↗

Color psychology: a critical review.

A review of the field commonly referred to as color psychology poses a number of organizational problems stemming from the size and diversity of the literature, the range of issues investigated, and the different degrees of experimental rigor exercised. As a selective approach is both inevitable and desirable, the focus of this review is on those laboratory studies involving an "evaluative" response to color patches or chips. Numerically, this research represents the main body of work in color psychology and in experimental aesthetics generally.

Arousal↗