Showing papers by "University of Wollongong published in 1988"

Significance test or effect size

Abstract: I describe and question the argument that in psychological research, the significance test should be replaced (or, at least, supplemented) by a more informative index (viz., effect size or statistical power) in the case of theory-corroboration experimentation because it has been made on the basis of some debatable assumptions about the rationale of scientific investigation. The rationale of theory-corroboration experimentation requires nothing more than a binary decision about the relation between two variables. This binary decision supplies the minor premise for the syllogism implicated when a theory is being tested. Some metatheoretical considerations reveal that the magnitude of the effect-size estimate is not a satisfactory alternative to the significance test.

The Kelvin impulse: application to cavitation bubble dynamics

Abstract: The Kelvin impulse is a particularly valuable dynamical concept in unsteady fluid mechanics, with Benjamin and Ellis [2] appearing to be the first to have realised its value in cavitation bubble dynamics. The Kelvin impulse corresponds to the apparent inertia of the cavitation bubble and, like the linear momentum of a projectile, may be used to determine aspect It is defined aswhere ρ is the fluid density, o is the velocity potential, S is the surface of the cavitation bubble and n is the outward normal to the fluid. Contributions to the Kelvin impulse may come from the presence of nearby boundaries and the ambient velocity and pressure field. With this number of mechanisms contributing to its development, the Kelvin impulse may change sign during the lifetime of the bubble. After collapse of the bubble, it needs to be conserved, usually in the form of a ring vortex. The Kelvin impulse is likely to provide valuable indicators as to the physical properties required of boundaries in order to reduce or eliminate cavitation damage. Comparisons are made against available experimental evidence.

Population structure in the coral Pavona cactus : clonal genotypes show little phenotypic plasticity

Abstract: Electrophoretic data were used to examine the relationship between genotype and growth form, and to assess the contribution of asexual reproduction to recruitment within six local populations of the agaricid coral Pavona cactus from the central and northern Great Barrier Reef. The data revealed the presence of highly replicated clonal genotypes in the five densest populations. In three cases, samples of 50 to 60 colonies collected from 25 m2 areas within the Eclipse Island and Pandora Reef populations each consisted of colonies with only two distinct 4-locus genotypes. More intensive sampling of the population at Eclipse Island showed that colonies with the same 4-locus genotypes were separated by distances of up to 93 m. In contrast, the population at Watson's Bay (Lizard Island) consisted of a few widely scattered and genetically distinct colonies. The samples collected from each population contained a range of growth forms including, in some cases, the entire morphological range described for this species. A strong association of genotype and growth form was detected in samples from all populations, with the exception of Watson's Bay where no such comparison was possible. Nevertheless, some genotypes were represented by more than one growth form and this could reflect the effects of limited phenotypic plasticity. The effects of asexual reproduction reduced the value of these data as a test of the genetic connectedness of the six populations studied. The genetic distance between samples was not simply correlated with geographic distance. This may reflect either the true structure of the breeding population(s) or the effects of asexual reproduction on estimates of allelic frequencies.

High-Order Nonlinear Diffusion

Abstract: A number of important physical processes, such as the flow of a surface-tensiondominated thin liquid and the diffusion of dopant in semiconductors are governedby the fourth-order nonlinear diffusion equation u, + («"«*„),: = 0 (n > 0) Theanalysis of such equations is doubly complex due to the nonlinearity and the highorder Here we present some of the more immediate and simple results for thisequation and our development parallels known results for the classical nonlineardiffusion equation u, = (u"u

Water stress plating hypersensitivity of yeasts: protective role of trehalose in Saccharomyces cerevisiae.

Abstract: Summary: Water stress plating hypersensitivity was studied in two strains of Saccharomyces cerevisiae, one of them being a mutant incapable of accumulating trehalose to significant levels. The wild-type strain was grown in a defined medium with glucose, maltose or ethanol as carbon/energy source. In each case plating hypersensitivity was demonstrated and resistance to the stress developed in the second half of the exponential growth phase. Development of resistance was accompanied by accumulation of trehalose and was apparently unrelated to glycerol content which, under these conditions, was always low. A qualitatively similar trend was observed in the mutant grown on glucose but trehalose levels remained low and recovery of stress resistance was only slight. Dinitrophenol induced trehalose breakdown in resting yeast and simultaneously induced the onset of plating hypersensitivity. A negative correlation was demonstrated between trehalose content and “plating discrepancy” (log colony count on “normal” agar—log colony count on stressing agar) for both strains under all experimental conditions. The correlation held for trehalose contents up to about 50 mg (g dry yeast)−1, above which the yeasts were apparently fully resistant. Trehalose was evidently a more effective compatible solute, per mole, than glycerol.

Evidence for low temperatures and biologic diversity in cretaceous high latitudes of australia.

Abstract: A diverse terrestial biota inhabited polar latitudes during the Cretacous, 105 to 130 Ma (million years ago), along what is now the southeast coast of Australia This biota, from rocks in the Otway and Strzelecki groups, cnsisted of more than 150 taxa of vertebrates, invertebrates, and plants. Oxygen isotope ratios in diagenetic calcite suggest that mean annual temperatures were most likely less than 5°C, and rings present in the fossil araucarian-podocarp-ginko woods indicate saonality. Southeastern Austalia, thus, seems to have had a cool, seasonal, nontropical climate. Dinosaurs that have been recovered are up to five species and three genera of hypsilophodontids, all of which were endemic, and three species of theropods. The occurrence of Allosaurus sp. and labyrinthodont amphibians, which had become extinct elsewhere in the Jurassic, indicate that isolation may have allowed extended surival of these taxa in Australia. In that dinosaurs coped with high latitude for at least 65 million years [Valaginian to Albian time in Australia and Campanian to Maastrictian time (80 to 65 Ma) in Alaska] suggests that cold and darkness may not have been prime factors bringing about the extinction of dinosaurs and some other groups at the Cretaceous-Tertiary boundary, unless they were prolonged.

Uniform-Field Flicker Masking in Control and Specifically-Disabled Readers

Abstract: Possible transient-system deficiencies in subjects with specific reading disabilities (SRDs) were investigated in groups of 13-year-old SRDs and control normal readers. In experiment 1, in which a 6 Hz uniform-field flicker (UFF) mask and a stationary test stimulus were used, it was found that the overall effect of UFF masking was to reduce differences in contrast sensitivity between SRDs and normal readers. In experiments 2a and 2b, with UFF masks of 6 and 20 Hz and a 6 Hz moving (experiment 2a) or flickering (experiment 2b) test stimulus, contrast sensitivity in both groups was decreased in the presence of the 6 Hz UFF mask. Only the control group, however, showed a further decrease in sensitivity with the 20 Hz UFF mask. This indicates that the groups differ in terms of a mechanism sensitive to high temporal frequencies. A 20 Hz counterphase flickering test stimulus was used in experiment 3 in the presence of 6 Hz UFF, and it was found that SRDs are less sensitive than controls to 20 Hz flicker across all spatial frequencies used. The 6 Hz mask, however, did not differentially affect the two groups. These findings provide further evidence for a transient-system deficit in the visual systems of SRDs, but also suggest a more complex situation by showing that the two groups differ in a high-temporal-frequency mechanism.

The Three Gap Theorem (Steinhaus Conjecture)

Abstract: This paper is concerned with the distribution of N points placed consecutively around the circle by an angle of α. We offer a new proof of the Steinhaus Conjecture which states that, for all irrational α and all N , the points partition the circle into arcs or gaps of at least two, and at most three, different lengths. We then investigate the partitioning of a gap as more points are included on the circle. The analysis leads to an interesting geometrical interpretation of the simple continued fraction expansion of α.

Legacy of the Golden Age: Recent Developments in the Methodology of Accounting

Abstract: It is often suggested in the accounting literature that there was a distinct change in the methodology employed by accounting theorists/researchers around 1970 Nelson (1973) has referred to the 1960s as the ‘golden age in the history of a priori research in accounting’ Since then, some have claimed a more scientific empirical methodology has been used However, there are distinct similarities in the methodological presuppositions in both periods and it is argued in this paper that contemporary researchers have a debt to the ‘golden age’ theorists for introducing the requirement of a rigorous standard of argument for effective and reliable accounting knowledge

The adjuvanticity of gamma inulin.

Abstract: Gamma-inulin (g-IN) is a polymorph identified as the active component of inulin preparations that specifically activates the alternative pathway of complement (APC). The APC is central to many leucocyte functions, including B cell activation. We show here that g-IN, when formulated as a pure, endotoxin-free, fine suspension insoluble at 37 degrees C and given at 50-100 micrograms per mouse, is a potent adjuvant for both humoral and cell-mediated responses to a variety of antigens. g-IN increased secondary IgG responses five- to 28-fold (P less than 0.001), using as antigen phosphorylcholine coupled to keyhole limpet haemocyanin; subclasses IgG 2a, 2b, and 3 were boosted several hundred-fold, IgG 1 10-fold. IgM and IgA were increased four- to six-fold. Delayed hypersensitivity, by footpad swelling after secondary challenge with sheep red blood cells (SRBC), was increased more than two-fold (P less than 0.001) if g-IN was included with the primary SRBC, equivalent to increasing primary doses 10-fold. g-IN was equally active if given 5 days before the primary SRBC. Thus it is an immune stimulant rather than a depot or vehicle for antigen. Mice primed subcutaneously with 30-300 HA units of H2N2 influenza virus (strain A/JAP) and challenged intranasally with a lethal dose of H1N1 virus (strain A/WSN) all died, but if g-IN was given with the primary antigen 50% of the mice survived (P less than 0.001), a deduced but not proven boost to cytotoxic T cell-mediated immunity. Unpublished work has shown that g-IN has no adverse effects at adjuvant-active doses.(ABSTRACT TRUNCATED AT 250 WORDS)

Lay beliefs about disordered eating

Abstract: Although “disordered eating,” as a set of psychiatric conditions, implicitly evaluates components of a social phenomenon, little attention has been paid to the boundaries between socially accepted and abnormal eating. Lay knowledge and evaluations of the formal criteria for a diagnosis of anorexia nervosa or bulimia were therefore examined. The results show that although males and females know more about anorexia nervosa than bulimia, the DSM-III criteria for anorexia nervosa, which involve the determined pursuit of slimness and a body image disturbance, were judged by very few people to be both uncommon and abnormal. Bulimia, however, seems to be much closer to what is commonly judged to involve unusual behavior.

Co-citation bibliometric modeling as a tool for s&t policy and r&d management: issues, applications, and developments

Abstract: Summary This chapter is a comprehensive analysis of one literature-based methodology for ‘modeling’ the intellectual organisation and content of scientific disciplines. The method, called ‘co-citation bibliometric modeling’, provides a detailed description of the international research front. It may describe new inter- or multi-disciplinary developments in science, identify the most rapidly evolving subdisciplinary topic areas, and characterise the research activity of nations and organisations. As a result, it has been or is being explored as an intelligence tool for use in science and technology policy by 6 national governments, and may be of interest to large, high technology-based corporations. The objective here is to provide: 1) a guide to the methodology and its limitations 2) a guide to uses and interpretations of the data as they have been explored in nationally sponsored studies 3) an analysis of major unresolved technical and policy relevant issues 4) an assessment of recent methodological improvements, and 5) an agenda for future investigations and applications of this information tool.

Metabolism and the Development of Endothermy

Abstract: The development of a complex multicellular adult mammal from a single cell is as wondrous and awesome as the evolution of mammals themselves from simple single cell organisms. The parallels between the ontogeny of organisms and their phylogeny have long been recognized and were originally expressed by Haeckel as “ontogeny recapitulates phylogeny”. This doctrine initially generated considerable discussion and although it is not now generally accepted, it is obvious that there is some relationship between the two. For example, much phylogenetic change is the result of changes in developmental rates and timing (Gould 1977).

Can honeybees pollinate Grevillea

Abstract: The likely impact of the honeybee on a native pollination system was examined by studying the effectiveness of honeybees (Apis mellifera) as pollen vectors of Grevillea × gaudichaudii, near Bargo, New South Wales. Honeybees were the most frequent visitors to Grevillea inflorescences at the study site. Bees were found to be specific in their foraging, because only one pollen type was represented in the corbicula of each bee returning to a hive but the Grevillea was not present in these pollen loads. Bees were observed foraging for nectar on Grevillea plants in the study area, but had no Grevillea pollen on their bodies and failed to transfer pollen to stigmas of 500 flowers during two hours of observations over two days. It is concluded that bees harvested nectar from this plant species without effecting pollination, and would therefore make the plants less attractive to native pollinators without compensating for any consequent reduction in reproductive success.

A survey and future predictions for the use of chip breaking in unmanned systems

Abstract: This paper is aimed at presenting the current status of the knowledge and the use of chip control in machining, with a view to identifying the further work required for total chip control in unmanned systems. The results of an extensive survey on chip control covering over 160 published works since 1900 have been classified and summarised in 11 chip control-associated keyword groups. A critical review of the present status of research and future directions are then presented. This highlights the need for developing knowledge-based systems on the basis of a coding and classification system and the machinability data banks featuring predictive machining theories. An extension to this off-line processing facility in the proposed knowledge-based system would be the use of an on-line sensor-based chip form monitoring technique.

Dispersed and Undispersed Dependency

Abstract: This study was aimed at developing a measure of Kelly's concept of dispersion of dependency and providing evidence for its usefulness in differentiating degree of dispersion of dependency. Smith and Grassle's (1977) adaptation of Hurlbert's diversity index, a measure used by biologists to differentiate degrees of species diversity, was applied to dependency grids, specifically “being helped” grids. The diversity index was shown to be both useful in differentiating prototypes of relatively dispersed and undispersed grids and robust. Furthermore, evidence was provided for its predictive validity using predictions made by Kelly concerning dependency construing associated with differences in dispersion of dependency. Greater dispersion of dependency was related to making more discriminations about dependencies, and undispersed dependency was related to relatively impermeable and preemptive construing. Thus the measure was shown to be satisfactory for identifying dispersion of dependency, such that, u...

Which Data-Collection Methods are Appropriate for A Constructive Psychology?

Abstract: The implications of some assumptions of personal construct psychology far research methodology are considered here. When four available models of data collection are examined, one proves to be the most appropriate for constructivists. The sequential stages of this model are identified, and the extent to which current data-collection methods include these stages is discussed. These constructivist assumptions also have implications for the criteria by which these methods are evaluated.

Headspace gas analysis as a measure of rancidity in corn chips

Abstract: Headspace analysis by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) has been used to identify and quantify volatiles formed in the oxidative deterioration of corn chips. The effect of light and temperature on the formation of propanal, pentanal and hexanal in stored chips was examined and the data correlated with the results of sensory evaluation. The procedure is suitable for determining concentrations of pentanal and hexanal below, one ppm, which is below the level where rancidity based on sensory evaluation is detected. Problems associated with solute partitioning and sample decomposition in the analysis also were investigated.