Showing papers by "Queensland University of Technology published in 1996"

The New Work Order

Abstract: Workplace democracy. Empowerment. Team leaders. Knowledge workers. This is the language of the new work order promoted by todays management, which promises more meaningful and satisfying work, greater respect for diversity, and more democratic distribution of knowledge. But Gee, Hull, and Lankshear find startling contradictions in this brave new workplaceescalating inequality between individuals, nations, and even continents. They show how newly created alliances between business, educators, and psychologists may point to a hidden capitalist agenda more interested in preserving the status quo than establishing a new work order. This book offers a compelling and controversial account of global capitalism in the information age and the ways it affects language, literacy, learning, and life chances. It will be of particular interest to students in education, business, sociology, sociolinguistics, and communication studies.

Haemochromatosis and HLA–H

Abstract: The recently identified can didate gene, HLA-H, for haemochromatosis (HH) by Feder et al. generated considerable scientific interest coupled with a degree of uncertainty about the likely involvement of this gene in this common iron metabolism disorder, Feder et al. found a single point mutation resulting in an amino acid substitution (C282Y) that was homozygous in 148 (83%) of their patients, heterozygous in 9 patients (5%) but completely absent in 21 patients (12%). They proposed that the lack of a causative mutation in HLA-H in 12% of their patients was because these cases were not linked to chromosome 6p. A significant weakness in this argument is that all familial studies of the disorder so far have concluded that HH is due to a single major HLA-linked gene5-7. The ultimate test for a candidate gene is the clear segregation of a mutation with the disorder in all patients. Thus, some of the uncertainty surrounding the role of HLA-H in HH may be resolved by the identification of complete concordance of the C282Y mutation (or some other mutation) in HLA H with disease status in HH families. One potential problem in the design of such an experimental analysis is that a number of studies have shown the presence of a predominant ancestral haplotype in all HH populations examined: Australian, French, Italian, UK and US Thus in the analysis of a putative causative mutation, it is important to include families with...

Blastocystis hominis revisited.

Abstract: Blastocystis hominis is a unicellular organism found commonly in the intestinal tract of humans and many other animals. Very little is known of the basic biology of the organism, and controversy surrounds its taxonomy and pathogenicity. There morphological forms (vacuolar, granular, and ameboid) have been recognized, but recent studies have revealed several additional forms (cyst, avacuolar, and multivacuolar). The biochemistry of the organism has not been studied to any extent, and organelles and structures of unknown function and composition are present in the cells. Several life cycles have been proposed but not experimentally validated. The form used for transmission has not been defined. Infections with the organism are worldwide and appear in both immunocompetent and immunodeficient individuals. Symptoms generally attributed to B. hominis infection are nonspecific, and the need for treatment is debated. If treatment appears warranted, metronidazole is suggested as the drug of choice, although failures of this drug in eradicating the organism have been reported. Infection is diagnosed by light microscopic examination of stained smears or wet mounts of fecal material. Most laboratories identify B. hominis by observing the vacuolar form, although morphological studies indicate that other forms, such as the cyst form and multivacuolar form, also should be sought for diagnosis.

Optimal scheduling of trains on a single line track

Abstract: This paper describes the development and use of a model designed to optimise train schedules on single line rail corridors. The model has been developed with two major applications in mind, namely: as a decision support tool for train dispatchers to schedule trains in real time in an optimal way; and as a planning tool to evaluate the impact of timetable changes, as well as railroad infrastructure changes. The mathematical programming model described here schedules trains over a single line track. The priority of each train in a conflict depends on an estimate of the remaining crossing and overtaking delay, as well as the current delay. This priority is used in a branch and bound procedure to allow and optimal solution to reasonable size train scheduling problems to be determined efficiently. The use of the model in an application to a “real life” problem is discussed. The impacts of changing demand by increasing the number of trains, and reducing the number of sidings for a 150 km section of single line track are discussed. It is concluded that the model is able to produce useful results in terms of optimal schedules in a reasonable time for the test applications shown here.

Scale-space properties of the multiscale morphological dilation-erosion

Abstract: A multiscale morphological dilation-erosion smoothing operation and its associated scale-space expansion for multidimensional signals are proposed. Properties of this smoothing operation are developed and, in particular a scale-space monotonic property for signal extrema is demonstrated. Scale-space fingerprints from this approach have advantages over Gaussian scale-space fingerprints in that: they are defined for negative values of the scale parameter; have monotonic properties in two and higher dimensions; do not cause features to be shifted by the smoothing; and allow efficient computation. The application of reduced multiscale dilation-erosion fingerprints to the surface matching of terrain is demonstrated.

Optimal scheduling of trains on a single line track

Abstract: This paper describes the development and use of a model designed to optimise train schedules on single line rail corridors. The model has been developed with two major applications in mind, namely: as a decision support tool for train dispatchers to schedule trains in real time in an optimal way; and as a planning tool to evaluate the impact of timetable changes, as well as railroad infrastructure changes. The mathematical programming model described here schedules trains over a single line track. The priority of each train in a conflict depends on an estimate of the remaining crossing and overtaking delay, as well as the current delay. This priority is used in a branch and bound procedure to allow and optimal solution to reasonable size train scheduling problems to be determined efficiently. The use of the model in an application to a 'real life' problem is discussed. The impacts of changing demand by increasing the number of trains, and reducing the number of sidings for a 150 kilometre section of single line track are discussed. It is concluded that the model is able to produce useful results in terms of optimal schedules in a reasonable time for the test applications shown here.

Tear meniscus measurement in the diagnosis of dry eye.

Abstract: Purpose. Assessment of the tear film meniscus is a quantitative, minimally invasive, direct measurement of tear film quantity. The aim of this study was to assess the efficacy of tear meniscus para...

The dehydroxylation of the kaolinite clay minerals using infrared emission spectroscopy

Abstract: The dehydroxylation of a series of the kaolinite clay minerals, kaolinite, halloysite and dickite, has been investigated by Fourier transform in situ infrared emission spectroscopy over a temperature range of 100 to 800 ~ at both 50 and 5 ~ intervals. Excellent correspondence was obtained between the high temperature emission spectra and FTIR absorption spectra of the quenched clay mineral phases. The major advantage of the technique lies in the ability to obtain vibrational spectroscopic information in situ at the elevated temperature. Dehydroxylation at a number of temperatures was determined by the loss of intensity of hydroxyl bands as indicated by intensity changes of the 3550 cm ~ to 3750 cm 1 emission spectra. As with all clay minerals, kaolinite clay mineral dehydroxylation is structure dependent. No clay phase changes occur until after dehydroxylation takes place. The kaolinite clay mineral loses the inner sheet and inner hydroxyl groups simultaneously, whereas dickite and halloysites are shown to lose the outer hydroxyls, as evidenced by the intensity loss of the -3684 cm 1 peak, before the inner hydroxyl groups as determined by the intensity loss of the 3620 cm 1 peak. Evidence for a high temperature stable hydroxyl band at 3730 cm ~ for dickite and halloysite was obtained. This band is attributed to the formation of a silanol group formed during the dehydroxylation process. It is proposed that the dehy- droxylation process for kaolinite takes place homogenously and involves 2 mechanisms. The dehydrox- ylation of dickite and halloysite takes place in steps, with the first hydroxyl loss taking place homogen- ously and the second inhomogenously.

Cultural Myths as Constraints to the Enacted Science Curriculum

Abstract: The common sense aspects of traditional practices promise to be a conservative force with respect to the efforts of policymakers to improve the quality of science learning in schools. This study of the teaching of grade I I chemistry indicates how an experi­ enced teacher made sense of his teaching roles in terms of four cultural myths related to the transmission of knowledge, being efficient, maintaining the rigor of the cur­ riculum, and preparing students to be successful on examinations. These cultural myths were supported in this study by the teacher and students and provided a strong rationale for maintaining the types of classroom practices that reformers are wanting to change. If teachers can be brought to a level of consciousness about myths such as these there is a chance that their viability can be addressed directly and alternative myths can be generated to propel reform in the direction advocated in the myriad re­ ports that presently exhort changes in policy and classroom practice. © 1996 John Wiley & Sons, Inc.

New Patterns in Global Television : Peripheral Vision

Abstract: Over recent decades, the flow of television programmes and services between nations has prompted concerns about `Cultural Imperialism', the idea that the powerful metropolitan nations at the centre of the world system are breaking down the integrity and autonomy of the peripheral countries. New Patterns in Global Television challenges that notion by showing that some of the countries outside the traditionally dominant centres have now developed strong television industries of their own, and have been expanding into regional markets, especially - but not exclusively - where linguistic and cultural similarities exist. This book brings together contributions from specialist researchers on the most dynamic of these regions: Latin America, India, the Middle East, Greater China and, in the English-speaking world, Canada and Australia. It provides the first comprehensive overview of the new patterns of flow in international television programme exchange and service provision in the satellite era, patterns unrecognised by the perspective of the prevailing theoretical orthodoxies in international communication research and policy.

Beta-cell apoptosis is responsible for the development of iddm in the multiple low-dose streptozotocin model

Abstract: Although insulin-dependent diabetes mellitus (IDDM) results from irreversible loss of beta cells, the mode of cell death responsible for this loss has not previously been categorized. In this study, the multiple low-dose streptozotocin (stz) model (intraperitoneal injection of stz at a concentration of 40 mg/kg body weight per day for five consecutive days) was used to investigate beta-cell death during the development of IDDM in male C57B1/6 mice. Apoptotic cells were evident by light microscopy within the islets of Langerhans of treated animals from day 2 (the day of the second stz injection) until day 17. Immunohistochemical localization of insulin to the dying cells confirmed the beta-cell origin of the apoptosis. Two peaks in the incidence of beta-cell apoptosis occurred: the first at day 5, which corresponded to an increase in blood glucose concentration, and the second at day 11, when lymphocytic infiltration of the islets (insulitis) was maximal. Insulitis did not begin until day 9, by which time treated animals had developed overt diabetes as revealed by blood glucose and pancreatic immunoreactive insulin (IRI) measurements. Beta-cell apoptosis preceded the appearance of T-cells in the islets and continued throughout the period of insulitis. Thus, whether induced by stz or a subsequent immune response, apoptosis is the mode of cell death responsible for beta-cell loss in the multiple low-dose stz model of IDDM.

Teaching and Learning in Environmental Education: Developing Environmental Conceptions.

Abstract: A theoretical model is presented for developing environmental conceptions that incorporate environmental knowledge, attitudes/values, and behavioral orientations. Developing conceptions in environmental education involves the use of a range of strategies designed to integrate an individual's environmental knowledge, attitudes/values, and behavior. The proposed approach broadens teaching in the area that traditionally has had an attitudes/values focus. The application of constructivist principles of learning provides a basis for encouraging students to become aware of, challenge inconsistencies in, and make an informed decision regarding their commitment to their own or alternative environmental conceptions. Examples are provided of strategies that may be adapted for use within this model.

A model of wound-healing angiogenesis in soft tissue

Abstract: Angiogenesis, or blood vessel growth, is a critical step in the wound-healing process, involving the chemotactic response of blood vessel endothelial cells to macrophage-derived factors produced in the wound space. In this article, we formulate a system of partial differential equations that model the evolution of the capillary-tip endothelial cells, macrophage-derived chemoattractants, and the new blood vessels during the tissue repair process. Chemotaxis is incorporated as a dominant feature of the model, driving the wave-like ingrowth of the wound-healing unit. The resulting model admits traveling wave solutions that exhibit many of the features characteristic of wound healing in soft tissue. The steady propagation of the healing unit through the wound space, the development of a dense band of fine, tipped capillaries near the leading edge of the wound-healing unit (the brush-border effect), and an elevated vessel density associated with newly healed wounds, prior to vascular remodeling, are all discernible from numerical simulations of the full model. Numerical simulations mimic not only the normal progression of wound healing but also the potential for some wounds to fail to heal. Through the development and analysis of a simplified model, insight is gained into how the balance between chemotaxis, tip proliferation, and tip death affects the structure and speed of propagation of the healing unit. Further, expressions defining the healed vessel density and the wavespeed in terms of known parameters lead naturally to the identification of a maximum wavespeed for the wound-healing process and to bounds on the healed vessel density. The implications of these results for wound-healing management are also discussed.

Effects on the compensatory responses to positive and negative lenses of intermittent lens wear and ciliary nerve section in chicks

Abstract: TEffects on the compensatory responses to positive and negative lenses of intermittent lens wear and ciliary nerve section in chicks.his study examined the ocular compensation to lens-induced defocus in chick and the effect of interrupting lens wear on a daily basis. Eyes fitted with +10 D lenses at hatching compensated rapidly, with almost complete compensation after 4 days of lens wear; they had decreased vitreous chamber depth compared to normal eyes and were thus hyperopic when the lenses were removed. In contrast, adaptation to the -10 D lenses was much slower, was still incomplete after 9 days of lens wear, and in this case, eyes had increased vitreous chamber depth and were myopic without the lenses. Adaptation improved when lens wear was delayed until 7 days after hatching. The effect of interrupting lens wear by periods of normal vision varied with the sign of the lenses worn. Hyperopia was always seen in response to +10 D lenses, although the magnitude of the response decreased as the duration of lens wear was decreased. In contrast, even brief periods of normal vision, i.e., 3 hr, prevented the development of myopia in response to the -10 D lenses; this apparent sensitivity to normal vision is similar to that reported for form-deprivation myopia. Ciliary nerve section used here to eliminate accommodation did not alter these response patterns.

The empirical analysis of fiscal illusion

Abstract: This paper examines the empirical analysis of the five main hypotheses subsumed under the generic term fiscal illusion. After placing these hypotheses within a common theoretical framework, the paper attempts to evaluate empirical research into the revenue-complexity hypothesis, the revenue- elasticity hypothesis, the flypaper effect, renter illusion, and debt illusion.

Student Teachers' Subject Matter Knowledge within the Domain of Area Measurement.

Abstract: This paper describes a research project whose major aim was to evaluate first-year teacher education students' understanding of subject matter knowledge in the domain of area measurement. In contrast to many previous approaches to evaluating teacher education students' subject matter knowledge, the approach adopted in this study not only focused on the student teachers' substantive knowledge but also on their knowledge about the nature and discourse of mathematics, their knowledge about mathematics in society and their dispositions towards mathematics. To this end, each student was clinically interviewed whilst engaged on a set of eight tasks that were developed for the study. The development of the tasks was a major component of the study and this is described in detail. The results of the tasks are given and the paper concludes with a discussion of the findings. This discussion focuses primarily on the implications that these results have for preservice mathematics education courses.

Genetics of educational attainment in Australian twins: Sex differences and secular changes

Abstract: The relative effects of genetic and environmental factors in producing individual differences in educational achievement are compared across women and men and over birth cohorts. In a large sample of Australian twin pairs, the heritability of self-reported educational attainment did not vary among women and men born before and after 1950. In a "psychometric" model of twin resemblance, based on separate self-reports in 1981 and 1989, genetic factors explained 57% of the stable variance in educational achievement, while environmental factors shared by twins accounted for 24% of the variance. Corrections for phenotypic assortative mating for educational level, however, suggested that estimated common-environmental effects could be entirely explained by the correlation between additive genetic values for mates. Taking this into account, heritability "true" educational attainment in Australia may be as high as 82% with the remaining variation being due to individual environments or experiences. Unlike previous studies in Scandinavian countries, results in Australia suggest that factors influencing educational success are comparable between women and men and for individuals born at different points during this century.

Evaluation of multiple frequency bioelectrical impedance and Cole-Cole analysis for the assessment of body water volumes in healthy humans

Abstract: OBJECTIVE: To assess the application of a Cole-Cole analysis of multiple frequency bioelectrical impedance analysis (MFBIA) measurements to predict total body water (TBW) and extracellular water (ECW) in humans. This technique has previously been shown to produce accurate and reliable estimates in both normal and abnormal animals. DESIGN: The whole body impedance of 60 healthy humans was measured at 496 frequencies (ranging from 4 kHz to 1 MHz) and the impedance at zero frequency, Ro, and at the characteristic frequency, Zc, were determined from the impedance spectrum, (Cole-Cole plot). TBW and ECW were independently determined using deuterium and bromide tracer dilution techniques. SETTING: At the Dunn Clinical Nutrition Centre and The Department of Biochemistry, University of Queensland. SUBJECTS: 60 healthy adult volunteers (27 men and 33 women, aged 18-45 years). RESULTS: The results presented suggest that the swept frequency bioimpedance technique estimates total body water, (SEE = 5.2%), and extracellular water, (SEE = 10%), only slightly better in normal, healthy subjects than a method based on single frequency bioimpedance or anthropometric estimates based on weight, height and gender. CONCLUSIONS: This study has undertaken the most extensive analysis to date of relationships between TBW (and ECW) and individual impedances obtained at different frequencies ( > 400 frequencies), and has shown marginal advantages of using one frequency over another, even if values predicted from theoretical bioimpedance models are used in the estimations. However in situations where there are disturbances of fluid distribution, values predicted from the Cole-Cole analysis of swept frequency bioimpedance measurements could prove to be more useful.

On the Security of Nonlinear Filter Generators

Abstract: By regarding a nonlinear filter keystream generator as a finite input memory combiner, it is observed that a recent, important attack introduced by Anderson can be viewed as a conditional correlation attack. Necessary and sufficient conditions for the output sequence to be purely random given than the input sequence is such are pointed out and a new, so-called inversion attack is introduced, which may work for larger input memory sizes in comparison with the Anderson's attack. Large input memory size and use of full positive difference sets and correlation immune nonlinear filter functions are proposed as new design criteria to ensure the security against the considered attacks.

Bioelectrical impedance for monitoring the efficacy of lymphoedema treatment programmes

Abstract: The treatment of lymphoedema includes a combination of massage, compression bandaging, and exercise. To date the most common technique of assessing the efficacy of treatment has involved estimating the total limb volume from circumferential measurements at fixed intervals along the limb. This study investigated the application of multiple frequency bioelectrical impedance analysis, MFBIA, to monitor the volume of lymphoedema in the upper limb of patients who developed this disorder following surgery for cancer of the breast. Daily measurements of both circumference and impedance of both the affected and unaffected limbs were recorded for 20 patients throughout their 4 week treatment programmes. Twenty control subjects were also monitored daily over a similar 4 week period. Prior to the commencement of treatment the bioimpedance technique detected a significant (P < 0.01) asymmetry between the two limbs of the control subjects, associated with handedness (P < 0.001). Circumferential estimates of limb volumes in the control group detected no asymmetry. Impedance measures of extracellular fluid showed all of the patients to lie outside the 95% confidence interval determined from the data of the control group. The trends of the impedance measures and the circumferential estimates of volume throughout the 4 week program were found to be significantly different (P < 0.05); MFBIA exhibiting a greater sensitivity in the detection of lymphoedema. The results demonstrate that MFBIA is significantly more sensitive than circumferential measurement both in the early diagnosis of lymphoedema and in monitoring change.

A multidimensional model of client success when engaging external consultants

Abstract: Too often the relationship between clients and external consultants is perceived as one of protagonist versus antagonist. Stories on dramatic, failed consultancies abound, as do related anecdotal quips. A contributing factor to many "apparently" failed consultancies is a poor appreciation by both the client and consultant of the client's true goals for the project and how to assess progress toward these goals. This paper presents and analyses a measurement model for assessing client success when engaging an external consultant. Three main areas of assessment are identified: 1 the consultant's recommendations, 2 client learning, and 3 consultant performance. Engagement success is empirically measured along these dimensions through a series of case studies and a subsequent survey of clients and consultants involved in 85 computer-based information system selection projects. Validation of the model constructs suggests the existence of six distinct and individually important dimensions of engagement success. Both clients and consultants are encouraged to attend to these dimensions in pre-engagement proposal and selection processes, and post-engagement evaluation of outcomes.

The politics of interviewing: power relations and accepting the gift

Abstract: The politics of interviewing were independently experienced by the three authors, each of whom used a different interviewing style. It was found that existing models of interviewing were inadequate, particularly with respect to the shifting dynamics of power in interview relationships. This paper results from intensive discussions between the three authors as they worked towards synthesizing their insights and creating a better understanding of the interviewing process and the politics of interviewing. We conclude that the interview is a gift received by the researcher, and participating in the processes of the production of knowledge inevitably means being embroiled in some uncomfortable contradictions. Specifically, the power of the interviewees in the giving of the interview and our own empowerment and indebtedness as the receivers of their gift is a contradiction that deserves more serious reflection than given in the traditional literature on interviewing.

On the rôle of angiogenesis in wound healing.

Abstract: Angiogenesis, the formation of blood vessels, may be described as a process whereby capillary sprouts are formed in response to externally supplied chemical stimuli. The sprouts then develop and organize themselves into a dendritic structure. Angiogenesis occurs during embryogenesis, wound healing, arthritis and during the growth of solid tumours. In this paper we present a mathematical model which describes the rŏle of angiogenesis as observed during (soft-tissue) wound healing. We focus attention on certain principal players involved in this complex process, namely capillary tips, capillary sprouts, fibroblasts, macrophage-derived chemical attractants, oxygen and extracellular matrix. The model consists of a system of nonlinear partial differential equations describing the interactions in space and time of the above substances. Numerical simulations are presented which are in very good qualitative agreement with experimental observations.

The Empirical Analysis Of Fiscal Illusion

Abstract: This paper examines the empirical analysis of the five main hypotheses subsumed under the generic term fiscal illusion. After placing these hypotheses within a common theoretical framework, the paper attempts to evaluate empirical research into the revenue-complexity hypothesis, the revenue-elasticity hypothesis, the flypaper effect, renter illusion, and debt illusion.

Kerf characteristics in abrasive waterjet cutting of ceramic materials

Abstract: An abrasive water jet (AWJ) can provide a more effective means for precision cutting of ceramic materials as compared with conventional machining methods, but many aspects about this cutting technology are still under flux and development. In this study, experimental techniques based on statistical experimental design principles and theoretical investigations were conducted to study AWJ cutting of alumina-based ceramics. Semi-empirical cutting depth equations are determined for the prediction and optimization of the AWJ cutting performance. Topographical characteristics of uncut-through kerf and the effects of various parameters are discussed. In addition, visualization studies are conducted to develop further understanding of the macromechanics of the AWJ cutting process.