Showing papers by "Queen's University published in 1986"

Development of criteria for the classification and reporting of osteoarthritis: Classification of osteoarthritis of the knee

Abstract: For the purposes of classification, it should be specified whether osteoarthritis (OA) of the knee is of unknown origin (idiopathic, primary) or is related to a known medical condition or event (secondary). Clinical criteria for the classification of idiopathic OA of the knee were developed through a multicenter study group. Comparison diagnoses included rheumatoid arthritis and other painful conditions of the knee, exclusive of referred or para-articular pain. Variables from the medical history, physical examination, laboratory tests, and radiographs were used to develop sets of criteria that serve different investigative purposes. In contrast to prior criteria, these proposed criteria utilize classification trees, or algorithms.

Density Functional Calculations of Molecular Bond Energies

Abstract: The calculation of molecular spectroscopic properties is an interesting application of the local density approximation (LDA) for the exchange-correlation energy of many-electron systems. LDA bond lengths and vibrational frequencies agree remarkably well with experiment. Dissociation energies are also reasonably good, but tend to overestimate the experimental results. Therefore, we consider in this work the effect of non-local gradient-type correction terms on LDA bond energies. In particular, we consider the gradient-corrected exchange-correlation functional of Langreth and Mehl, and also a semi-empirical exchange approximation recently developed by the present author.

The identification of nonlinear biological systems: Wiener and Hammerstein cascade models

Abstract: Systems that can be represented by a cascade of a dynamic linear subsystem preceded (Hammerstein cascade model) or followed (Wiener cascade model) by a static nonlinearity are considered Various identification schemes that have been proposed for the Hammerstein and Wiener systems are critically reviewed with reference to the special problems that arise in the identification of nonlinear biological systems Examples of Wiener and Hammerstein systems are identified from limited duration input-output data using an iterative identification scheme

Rapid chemosensitivity testing of human lung tumor cells using the MTT assay.

Abstract: Numerous procedures have been described which test the chemosensitivity of tumor cell lines. A major disadvantage of most of these assays is that practical limitations prevent the testing of more than a few variables. We have adapted a rapid and efficient colorimetric assay for testing the chemosensitivity of human lung tumor cells. In this assay, a tetrazolium salt (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide, MTT) is converted to a colored formazan product by enzymes active only in living cells. The MTT assay may be carried out entirely in 96-well microtiter plates, so that large experiments examining a number of variables can be readily performed. Thus, drug concentration, time of exposure to drug, length of assay, and cell density can be varied and tested. Moreover, the simplicity of this assay allows simultaneous testing of multiple drugs on multiple cell lines. Finally, the MTT assay is useful for monitoring the development of multidrug-resistant cells in culture.

The effect of density on the gastric emptying of single- and multiple-unit dosage forms

Abstract: The gastric emptying of pellets and single units of different densities has been followed in healthy subjects using the technique of gamma scintigraphy. The gastric emptying of the light pellets was affected by their buoyancy in the upper part of the stomach. However, the mean gastric emptying rates of pellets and single units were not significantly affected by density. Floating or buoyant delivery systems may have little advantage over conventional systems. The presence of food in the stomach was found to be the major factor in determining the gastric emptying of single units.

The identification of nonlinear biological systems: LNL cascade models

Abstract: Systems that can be represented by a cascade of a dynamic linear (L), a static nonlinear (N) and a dynamic linear (L) subsystem are considered. Various identification schemes that have been proposed for these LNL systems are critically reviewed with reference to the special problems that arise in the identification of nonlinear biological systems. A simulated LNL system is identified from limited duration input-output data using an iterative identification scheme.

Metaphor in the thinking of teachers: An exploratory study

Abstract: (1986). Metaphor in the thinking of teachers: An exploratory study. Journal of Curriculum Studies: Vol. 18, No. 2, pp. 197-209.

Perception of texture by vision and touch: multidimensionality and intersensory integration.

Abstract: A series of six experiments offers converging evidence that there is no fixed dominance hierarchy for the perception of textured patterns, and in doing so, highlights the importance of recognizing the multidimensionality of texture perception. The relative bias between vision and touch was reversed or considerably altered using both discrepancy and nondiscrepancy paradigms. This shift was achieved merely by directing observers to judge different dimensions of the same textured surface. Experiments 1, 4, and 5 showed relatively strong emphasis on visual as opposed to tactual cues regarding the spatial density of raised dot patterns. In contrast, Experiments 2, 3, and 6 demonstrated considerably greater emphasis on the tactual as opposed to visual cues when observers were instructed to judge the roughness of the same surfaces. The results of the experiments were discussed in terms of a modality appropriateness interpretation of intersensory bias. A weighted averaging model appeared to describe the nature of the intersensory integration process for both spatial density and roughness perception.

Differential Timing of Spring Migration in Wood Warblers (Parulinae)

Abstract: -Spring migration patterns of 18 species of paruline warbler at Prince Edward Point, Ontario showed that males arrived earlier than females in all species. Adult males arrived significantly earlier than second-year males in American Redstarts (Setophaga ruticilla), and there was evidence for a similar trend in other species. The difference in mean arrival dates between the sexes was greatest in species that arrived earliest. Similarly, within species, the difference between sexes was greatest in years when the males arrived earliest. For individuals within a species there was a significant negative correlation between arrival date and wing length; however, males of a particular size generally arrived earlier than females of the same size. Thus, larger size may be an advantage to early arrival, but is not sufficient to explain the difference in arrival between sexes. Species that winter furthest north arrived earliest, but sexual differences in wintering grounds have not been reported. These results are consistent with the hypothesis that males are selected to arrive as early as food resources or climatic conditions are adequate, whereas females arrive later, closer to the time when they can successfully begin nesting. Received 19 August 1985, accepted 11

Non-invasive technique for obtaining fluorescence excitation and emission spectra in vivo.

Abstract: An intensified photodiode array forms the heart of a sensitive spectrophotofluorometry system that permits the rapid and non-invasive determination of fluorescence emission spectra in the skin of living, non-anesthetized animals. Using this system, we found it possible to obtain good emission and excitation spectra of the material responsible for the weak red fluorescence that characterizes normal mouse skin, and to follow the biosynthesis and subsequent clearance of protoporphyrin IX in the skin of non-anesthetized mice that had been given various doses of the porphyrin precursor 5-aminolevulinic acid.

Delayed plumage maturation in passerine birds: reliable signaling by subordinate males?

Abstract: Three hypotheses (Cryptic, Female Mimicry, and Winter Adaptation) have been pro- posed to explain the occurrence of delayed plumage maturation (DPM) in passerine birds. We show that each of these hypotheses is really a composite of two different questions about: 1) the proximate function of dull plumage in second year (SY) males and 2) the selective mechanism that has favored that proximate function. We review the three hypotheses in the context of this dis- tinction, and we find little evidence clearly supporting any of them. We propose a new Status Signaling Hypothesis (SSH) suggesting that dull SY male plumage is a reliable signal of subordi- nance. We suggest that female choice based on male plumage color (as an index of male quality) is the selective mechanism that has favored subordinate status signaling by SY males. If females prefer bright males, then dull plumage may be a reliable signal of subordinance and SY males may experience reduced levels of aggression from adult males. Male characters (like plumage color) are most likely to be the object of female choice when males defend simple nesting territories with little or no variation in territory quality. In such a system, SY males with low resource-holding potential would benefit (via matings or experience) by signaling subordinance and being allowed to settle among more brightly colored adults. Thus, DPM is expected to be more prevalent when males defend simple nesting territories. This prediction of the SSH is supported by data from the literature-a significantly higher proportion of species with DPM defend simple nesting territories (versus all-purpose territories) than do species without DPM.

Bridging the paradigm gap: second language acquisition theory and indigenized varieties of English

Abstract: It is argued that there is a paradigm gap that has prevented research on second-language acquisition (SLA) theory and indigenized varieties of English (IVEs) from making substantive contributions to each other While it is true that studies of IVEs and their acquisition have been impressionistic (non-empirical) and often atheoretical, the lack of rapprochement is also due to SLA theory's excessive reliance for its models on acquisition in native-speaker environments and ignorance of the dynamics of language use in multilingual settings. This has resulted in the neglect and misunderstanding of IVEs. It is shown that IVEs represent a number of significant sociolinguistic and psycholinguistic variables, the investigation of which will put SLA theory on firmer theoretical ground and give it greater explanatory power

Geometric test for Late Cretaceous-Paleogene intracontinental transform faulting in the Canadian Cordillera

Abstract: The Tintina trench-northern Rocky Mountain trench (TT-NRMT) fault zone and the Fraser River-Straight Creek (FR-SC) fault zone are separate, en echelon, concentric, small-circle fault segments of a composite intracontinental transform fault zone more than 2500 km long that cuts diagonally across the Canadian Cordillera, from the outboard part of a tectonic collage of accreted foreign terranes in the south into the North American preaccretionary continental margin in the north. Most of the 450 km of right-hand slip on the TT-NRMT fault zone was transformed southward during the Late Cretaceous and Paleocene into oblique convergence in the southern Canadian Rockies; the remainder, probably comprising less than 100 km, was transformed southwestward during early and middle Eocene time via a zone of distributed shear and east-west crustal stretching into right-hand slip on the en echelon FR-SC fault zone. These interpretations, based on regional systematic mapping of geologic structures, are in conflict with interpretations of paleomagnetic measurements that call for more than 1000 km of post-mid-Cretaceous, right-hand displacement along the general locus of the TT-NRMT fault zone, involving foreign terranes and the parts of North America to which they had been accreted. This paradox must be resolved.

Approximate Binomial Confidence Limits

Abstract: This article examines the accuracy of normal approximations to confidence limits for the binomial (n, p) parameter p. The method of getting “exact” values from an F table is too slow for practical use and useless for large n. The two usual approximations have unsatisfactory accuracy both for small n and asymptotically, and the simpler one lacks an invariance property of the confidence limit. Hall's (1982) approximation also lacks invariance and, even when symmetrized, has unsatisfactory accuracy. Pratt's (1968) approximation has excellent accuracy for all n. Inversion of a Molenaar (1973) normal approximation to the binomial gives better asymptotic accuracy than Pratt's approximation, but poor values for observations close to n.

Salience of gender and sex composition of ad hoc groups: An experimental test of distinctiveness theory.

Abstract: Does the salience of an individual group member's gender depend on the group's sex composition? According to McGuire's distinctiveness theory, even for "momentary" or ad hoc groups, gender would be more salient in the spontaneous self-concepts of members of the minority sex in mixed-sex groups than in other conditions. To test this prediction experimentally, we manipulated the sex composition of 3-peison groups, which resulted in four types: All male, all female, lone male, and lone female. Within these group contexts, subjects responded to two open-ended probes of spontaneous self-concept (i.e., "Tell me what you are" and "Tell me what you are not"), with order counterbalanced, and subsequently completed a structured measure of gender identity (Personal Attributes Questionnaire). Chi-square analyses of whether gender was mentioned on the "Tell me about yourself" probe supported distinctiveness theory. Implications of this finding for distinctiveness theory and the psychology of self are discussed. What factors influence one's self-perception and self-concept? According to McGuire's (1984) distinctiveness theory, a person who takes a complex stimulus such as the self as an object of perception notices her or his distinctive traits and personal characteristics more readily because of their greater informational richness and value for discriminating self from others. Given that distinctive features are supposedly salient to the individual, they should theoretically be mentioned more frequently in one's spontaneous self-description. In tests of this perspective, McGuire and his associates analyzed the content of children's written or oral answers to being asked to "tell us about yourself." McGuire emphasized an open-ended approach in order to determine what dimensions are salient to the respondent. A structured measure, on the other hand, presumably compels respondents to define themselves in terms of dimensions chosen by the researcher. The central prediction of distinctiveness theory is that an individual's distinctive traits in relation to other people in a given context will be mentioned more frequently than their more common traits in response to open-ended probes. This prediction has been consistently supported in studies conducted by McGuire and his colleagues over the past decade. For example, testing within classes of sixth-grade students, McGuire and Padawer

Functional Anatomy of the Shoulder Complex

Abstract: The shoulder complex, together with other joint and muscle mechanisms of the upper limb, primarily is concerned with the ability to place and control the position of the hand in the visual work space in front of the body. The shoulder mechanism provides the upper limb with a range of motion exceeding that of any other joint mechanism. The placement of the hand is determined by four components of the shoulder complex: the glenohumeral, acromioclavicular, and sternoclavicular joints and the scapulothoracic gliding mechanism. The clavicular joints permit the scapula to move against the chest wall during movements of the arm, allowing the glenoid fossa to follow the head of the humerus, and thus contribute significantly to total arm movement. The functional interrelationships between the glenohumeral, scapulothoracic, and clavicular joint mechanisms are critical in providing a full, functional ROM. Any pathological condition of any one of these mechanisms will disturb upper limb function. The ligamentous and periarticular structures of the shoulder complex combine in maintaining the joint relationships, withstanding the forces applied to the joint surfaces, and stabilizing the dependent limb.

Characterization of the supernumerary chromosome in cat eye syndrome.

Abstract: Most individuals with cat eye syndrome (CES) have a supernumerary bisatellited chromosome which, on the basis of cytogenetic evidence, has been reported to originate from either chromosome 13 or 22. To resolve this question, a single-copy DNA probe, D22S9, was isolated and localized to 22q11 by in situ hybridization to metaphase chromosomes. The number of copies of this sequence was determined in CES patients by means of Southern blots and densitometry analysis of autoradiographs. In patients with the supernumerary chromosome, four copies were found, whereas in one patient with a duplication of part of chromosome 22, there were three copies. Therefore, the syndrome results from the presence of either three or four copies of DNA sequences from 22q11; there is no evidence that sequences from other chromosomes are involved. This work demonstrates how DNA sequence dosage analysis can be used to study genetic disorders that are not readily amenable to standard cytogenetic analysis.

Demi-span as a measure of skeletal size

Abstract: Height and demi-span (sternal notch to finger roots with arm out-stretched laterally) were measured using standard procedures in 125 normal young to middle-aged European subjects. Highly significant correlations (r = 0.74) were obtained between the two variables. The reliability of all measurements was good. The standard deviation of the differences on retest was always less than +/- 0.5 cm. Demi-span is therefore a practical alternative measurement of skeletal size.

Effect of inactivity and passive stretch on protein turnover in phasic and postural rat muscles

Abstract: A state of hypokinesia and hypodynamia has been induced in the hindlimb muscles of the rat (100 g) using a suspension model. The ensuing muscle atrophy was assessed by reference to muscles in fully...

Testing the Martingale Hypothesis in Deutsche Mark Futures with Models Specifying the Form of Heteroskedasticity

Abstract: We examine the form of heteroskedasticity in Deutsche Mark futures price data and compare different specifications of the particular way that the variance is changing over time. The martingale hypothesis is tested with daily and weekly rates of change of futures prices for the Deutsche Mark and some evidence is found against this hypothesis in analyses of daily data from 1981 to 1985. This rejection of the martingale hypothesis may be attributed to trading day effects in foreign currency prices and the resulting day-of-the-week patterns in futures prices. When the martingale hypothesis is tested with weekly data the null hypothesis is retained.