Showing papers by "University of Sydney published in 1987"
TL;DR: This article provided an overview of findings and of research methodology used to study students' evaluations of teaching effectiveness, and examined implications and directions for future research, concluding that students' ratings are primarily a function of the instructor who teaches a course rather than the course that is taught, and relatively valid against a variety of indicators of effective teaching.
1,315 citations
TL;DR: Most patients with chronic inflammatory demyelinating polyradiculoneuropathy had made a good recovery and were independent, but 7 patients had either died or were completely immobilized as a result of their disease.
Abstract: Ninety-two patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) have been studied in order to define better the clinical features, course and prognosis of the condition and to identify possible aetiological factors. Sural nerve biopsy was performed on 87 subjects. Electrophysiological studies were undertaken on all patients and demonstrated marked slowing of motor conduction and impairment of sensory conduction. The onset was usually gradual but there was a rapid rate of onset in 15 (16%) patients. Males were more commonly affected than females. Weakness and paraesthesiae were the most common symptoms but pain was frequently a feature. Age of onset ranged from 2 to 72 years. Sixty patients (65%) had a relapsing course and 32 patients (35%) a progressive or monophasic course; there was a significantly earlier age of onset in patients with relapsing disease. Thirty-two patients (35%) gave a history of preceding infection or some other possible antecedent precipitating event and there was a significantly higher titre for cytomegalovirus antibodies in the serum of patients with CIDP than in controls. The patients were followed up for an average time of approximately ten years. Most patients (73%) had made a good recovery and were independent, but 7 patients had either died or were completely immobilized as a result of their disease. The value of treatment with corticosteroid therapy, immunosuppressive agents and plasma exchange is discussed.
424 citations
TL;DR: In this paper, the authors examined the multifaceted, hierarchical structure of self-concept, a substantive issue; and demonstrated the use of confirmatory factor analysis and hierarchical CFA and examined potential problems with their use and interpretation.
Abstract: This investigation (a) tested the ability of an a priori hierarchical structure of self-concept derivedfrom the Shavelson model to explain responses to the Self Description Questionnaire (SDQ) III, and (b) demonstrated the application and problems with the use of hierarchical confirmatory factor analysis (HCFA). A first-order factor analysis clearly identified all 13 facets of self-concept that the SDQ III is designed to measure. A series of HCFA models supported the separation of the 13 SDQ III facets of self-concept into academic and nonacademic components, and the academic facets into math/academic and verbal/academic components. However, support for separation of nonacademic facets into the physical, social, and moral second-order factors was not strong. Third-order HCFA models resulted in a clearly defined hierarchical general self-concept that was substantially related to Esteem and to physical, social, and emotional components of self-concept, but not to the academic and moral components. However, the hierarchy was so weak that first-order facets could not be accurately inferred from the higher order facets. The purposes of this study are to (a) examine the multifaceted, hierarchical structure of self-concept, a substantive issue; and (b) demonstrate the use of confirmatory factor analysis (CFA) and hierarchical CFA (HCFA) and examine potential problems with their use and interpretation, a methodological issue. Self-Concept: A Multifaceted, Hierarchical Construct Self-concept research has suffered from a paucity of theoretical models and psychometrically sound measurement instruments. Shavelson, Hubner, and Stanton (1976) reviewed theoretical and empirical research and developed a multifaceted, hierarchical model of self-concept that served as a basis for the Self Description Questionnaire (SDQ) instruments. In one possible representation of the model, Shavelson et al. posited a general self-concept at the apex of his model
333 citations
01 Oct 1987
TL;DR: If hGK-1 is expressed, its product represents a new, and possibly the only other enzyme with true kallikrein-like specificity in man, which is very different from mouse and rat, which each have a large multigene family.
Abstract: To isolate a human glandular kallikrein gene, a human genomic library was screened with a probe made from a mouse kallikrein cDNA (pMK-1). Overlapping clones were obtained and nucleotide sequence determination showed that they together contained a human glandular preprokallikrein gene, hGK-1, of 5.2 kb. The gene encoded a unique preproprotein of 261 amino acids. The sequence of the mature 237-amino-acid protein had 66% homology with the sequence predicted for human kallikrein synthesized in the pancreas, kidney, and salivary gland. Moreover, it had even stronger homology (78%) with human prostate-specific antigen. The latter lacks an aspartic acid residue essential for kallikrein-specific cleavage, whereas the sequence of this new protein had all of the attributes needed to confer kallikrein-like specificity. Southern blotting indicated that the number of glandular kallikrein genes in man could be limited to three, a situation very different from mouse and rat, which each have a large multigene f...
320 citations
TL;DR: The structure of poplar plastocyanin in the reduced (CuI) state has been determined and refined, using counter data recorded from crystals at pH 3.8 and 7.8, and the trigonal geometry of the Cu atom strongly favours CuI, so that this form of the protein should be redox-inactive.
304 citations
TL;DR: It is concluded that cross‐sectional studies of BR to identify children with BHR probably do not reflect the prevalence of asthma in populations of children, and measurements of BR in populations are useful for defining a group of children whose airways behave differently from those of the majority.
Abstract: In order to explore the relationship between bronchial hyperresponsiveness (BHR) to inhaled histamine, respiratory symptoms and diagnosed asthma in children, we undertook a cross-sectional study of 2363 Australian schoolchildren aged 8-11 years. The methods used included a self-administered questionnaire to parents, which was shown to have a high degree of repeatability, and a histamine inhalation test to measure bronchial responsiveness (BR). The study showed that 17.9% of children had BHR, defined as a 20% fall in FEV1 at a provoking dose of histamine (PD20 FEV1) of less than 7.8 mumol. The distribution of PD20 FEV1 appeared to be continuous. Most children with PD20 FEV1 values less than 1.0 mumol had symptoms of asthma. However, 6.7% of children had BHR without symptoms or a previous diagnosis of asthma and 5.6% had had a diagnosis of asthma but had no BHR. Although there was a good association between BHR and respiratory symptoms, questionnaire data of wheeze and diagnosed asthma do not reflect accurately the level of BHR in the community. We conclude that cross-sectional studies of BR to identify children with BHR probably do not reflect the prevalence of asthma in populations of children. However, the strong association between BHR and symptoms, particularly in children with severe and moderate BHR, suggests that measurements of BR in populations are useful for defining a group of children whose airways behave differently from those of the majority. Prospective studies are needed to define the level of BHR that is associated with important sequelae.
302 citations
TL;DR: There was a significant association between bronchial hyperresponsiveness and respiratory symptoms, atopy, smoking, and abnormal lung function, and there was no association with age, sex, or recent respiratory tract infection.
Abstract: The prevalence of bronchial hyperresponsiveness in adult populations is not known. To document its prevalence and distribution and to determine the factors associated with it, a random sample of the adult population of Busselton, Western Australia, was studied. Spirometric function, bronchial responsiveness to histamine, and atopic responses to skin prick tests were measured. Respiratory symptoms were determined by questionnaire. Data were obtained from 916 subjects. Of these, 876 underwent a histamine inhalation test and bronchial hyperresponsiveness to histamine (defined as a dose of histamine provoking a 20% fall in FEV1 equal to or less than 3.9 mumol) was found in 10.5%. Another 40 subjects with poor lung function were tested with a bronchodilator and 12 were found to have bronchial hyperresponsiveness (defined as a greater than 15% increase in FEV1), making the total prevalence of bronchial hyperresponsiveness 11.4%. The prevalence of current asthma, defined as bronchial hyperresponsiveness plus symptoms consistent with asthma in the last 12 months, was 5.9%. The distribution of bronchial hyperresponsiveness in the studied population was continuous. There was a significant association between it and respiratory symptoms, atopy, smoking, and abnormal lung function (p less than 0.001 for all associations). There was no association with age, sex, or recent respiratory tract infection.
293 citations
288 citations
TL;DR: It is concluded that postrecruitment competitive processes play an important role in restricting adult population size in P. amboinensis, at least over the range of densities and on the spatial scale examined.
Abstract: Considerable discussion has arisen over whether population limitation in coral reef fishes is achieved through postrecruitment processes or through factors operating prior to recruitment that lead to insufficient numbers to saturate resources. This paper presents the results of two field experiments designed to document and measure the relative effects of recruitment and subsequent intraspecific competition on populations of the plank- tivorous damselfish Pomacentrus amboinensis, a common species on the Great Barrier Reef. I tested for effects of conspecifics on juvenile mortality, growth, and maturation by manipulating population densities on coral rubble patch reefs. Each experiment examined the potential for competition among juveniles, and between juveniles and adults. The first experiment manipulated the densities of recently settled recruits; the second manipulated 1-yr-old juveniles using a similar experimental design. There were no consistent effects of juvenile density or of adult presence/absence on juvenile survivorship, during either the 0 + yr or the 1 + yr. However, there were substantial effects on growth and maturation. During the 1 st 8 mo of experiment 1, growth was inversely related to initial juvenile density, but was not affected by the presence of adults. A marked negative effect of adults on juvenile growth developed as juveniles approached an age of 1 yr. This effect developed early in experiment 2. Both the mean and the variance in 1 + yr growth were reduced in the presence of adults. Adults primarily affected the growth of the initially largest, behaviorally dominant juveniles. A significantly greater number of 0 + yr and 1 + yr juveniles reached a mature size after 1 yr in treatments without adults present. The numbers maturing were not related to initial density, either with adults present or absent. It is concluded that postrecruitment competitive processes play an important role in restricting adult population size in P. amboinensis, at least over the range of densities and on the spatial scale examined. The mechanism, however, is not one of those traditionally considered in equilibrial models. That is, competition does not appear to modify recruit- ment or mortality patterns directly, but influences numbers maturing through density- dependent effects on maturation time.
244 citations
TL;DR: It is concluded that the umbilical artery flow velocity waveform systolic/diastolic ratio measures the reflection coefficient at the peripheral vascular bed (the "resistance vessels") of the placenta.
234 citations
TL;DR: Sexual abuse appears to have long-term adverse consequences for many of the victims, which may have implications for their ability to relate to others, for the adult friendships they will make, and eventually for the way they will relate to their own children.
TL;DR: Aerosol steroids, rather than theophylline, are the treatment of choice when reduction in the severity of BHR is the aim of treatment in patients with severe asthma.
Abstract: In a double-blind crossover study, we compared the relative effects of inhaled beclomethasone dipropionate (BDP) 800 µg per day and oral theophylline on the severity of bronchial hyperresponsiveness (BHR) to histamine. Daily doses of theophylline were sufficient to keep serum levels between 55 and 110 µmol/L. The subjects were 26 patients with severe asthma whose symptoms were inadequately controlled by regular treatment with inhaled salbutamol. The severity of BHR improved within 3 wk in the group treated with BDP, whereas no change occurred in the group treated with theophylline. There were no significant changes in FEV1 in either group during the study. When BDP was changed to theophylline there was a deterioration in BHR. Aerosol steroids, rather than theophylline, are the treatment of choice when reduction in the severity of BHR is the aim of treatment in patients with severe asthma.
TL;DR: Investigating the time course and magnitude of cellular degeneration in the ganglion cell layer and the presumptive amacrine and bipolar regions of the inner nuclear layer during the development of the retina in the rat suggests that two phases of cell death occur in the Ganglioncell layer: during the first postnatal week the majority of dying cells areganglion cells, and in the second, most cell death is due to a loss of displaced amACrine cells.
Abstract: We have investigated the time course and magnitude of cellular degeneration in the ganglion cell layer and the presumptive amacrine and bipolar regions of the inner nuclear layer during the development of the retina in the rat. Pyknotic profiles are present in the ganglion cell layer during the first 2 postnatal weeks, reaching peak numbers during the first 4 postnatal days (corresponding to the time of greatest loss of ganglion cells and their axons: Potts et al., '82; Lam et al., '82; Perry et al., '83). Two observations suggest that the majority of pyknotic profiles present in the ganglion cell layer during the second postnatal week are not ganglion cells. First, following injection of kainic acid into one superior colliculus, degenerating ganglion cells in the contralateral retina are cleared within 24-48 hours. Therefore, since most ganglion cell and axon loss occurs within the first postnatal week, few of the pyknotic profiles present in the second week are likely to be ganglion cells. Second, the time course of cellular degeneration in the ganglion cell layer during the second postnatal week follows a very similar pattern to that seen in the presumptive amacrine sublayer of the inner nuclear layer. Such a correspondence suggests that two phases of cell death occur in the ganglion cell layer: during the first postnatal week the majority of dying cells are ganglion cells, and in the second, most cell death is due to a loss of displaced amacrine cells. In the inner nuclear layer pyknotic profiles are most numerous in the presumptive amacrine region on postnatal days 6 and 7, and in the presumptive bipolar region on day 10. Synaptogenesis in the inner plexiform layer occurs later but reflects the order of cell death. Thus, conventional (presumed amacrine) synapses were first observed on day 11 and synaptic ribbons (indicative of bipolar synapses) on day 13. These observations suggest that amacrine and bipolar cells initiate synapses only after their numbers have stabilized.
TL;DR: In this paper, a rigorous electromagnetic theory of the diffraction of radiation by a circular aperture in a thick screen is developed, and the effects of varying the thickness of the screen and varying the wavelength, polarization, and angle of incidence of the incident wave on the reflection and transmission properties of a screen are investigated.
Abstract: A rigorous electromagnetic theory of the diffraction of radiation by a circular aperture in a thick screen is developed. In particular, the case of an incident plane wave is considered, and the effects of varying the thickness of the screen and of varying the wavelength, polarization, and angle of incidence of the incident wave on the reflection and transmission properties of the screen are investigated.
TL;DR: Two new murine monoclonal antibodies reactive with the human platelet glycoprotein (GP) Ib-IX complex have been produced by the hybridoma technique, and combined data suggests that GP lb and GP IX are fully complexed in the intact platelet membrane.
TL;DR: In this paper, the radiation pattern of a bow-tie antenna of finite length and infinitesimal thickness, placed on a lossless dielectric substrate, is analyzed based on a representation of the current density on the metal surface of the antenna as a sum of an imposed quasistatic term and a set of current modes with unknown amplitudes.
Abstract: A new formulation is discussed for the rigorous calculation of the radiation pattern of a bow-tie antenna of finite length and infinitesimal thickness, placed on a lossless dielectric substrate. The analysis is based on a representation of the current density on the metal surface of the antenna as a sum of an imposed (quasistatic) term and a set of current modes with unknown amplitudes. Free-space fields that are expressed in terms of continuous spectra of symmetrized plane waves are matched to the current modes using the method of moments. The resulting set of equations are solved for the unknown current amplitudes. The calculations show that for increasing bow length the antenna impedance spirals rapidly to a value predicted by transmission line theory. The theory also shows that the E -plane pattern of a two wavelength, 60\deg bow-tie antenna is dominated by low-loss current modes propagating at the dielectric wavenumber. As the bow tie narrows, the loss of the modes increases, and the dominant wavenumber tends to the quasistatic value. Pattern measurements made at 94 GHz are shown to agree well with theoretical predictions. Measurements for a long-wire antenna, a linear array of bow-tie elements, and a log-periodic antenna are also presented.
TL;DR: The combined results suggest that the inhibition by SZ 2 of collagen- and PAF-induced aggregation of normal platelets is steric and are consistent with the glycoprotein Ib complex and the platelet collagen andPAF receptor(s) being adjacent in the human platelet plasma membrane.
TL;DR: In this paper, 300 patients at high fetal risk (mean gestational age 34 wk) were randomised to a group for antenatal doppler umbilical artery waveform studies and a control group.
TL;DR: Microinjections of the excitant amino acid D,L-homocysteic acid into a restricted part of the midbrain periaqueductal grey of unanaesthetized decerebrate cats evoked a distinctive pattern of facio-vocal and cardiovascular changes characteristic of a defence reaction, including pupillary dilatation, howling vocalization, an increase in arterial pressure and heart rate, and skeletal muscle vasoconstriction.
TL;DR: In this paper, a mixture fraction approach was used to measure the volume fraction of a turbulent ethylene diffusion flame and compared with predictions, and the results showed that in the lower parts of the flame this formulation is not adequate.
Abstract: Soot volume fraction measurements are made in turbulent ethylene diffusion flames and are compared with predictions. The theoretical model is based on mixture fraction distributions in the flame and measured soot volume fractions are correlated against predicted mixture fraction. The results show that in the lower parts of the flame this formulation is not adequate. However, the maximum soot concentrations further up the flame are less dependent on residence time and a mixture fraction approach may be useful here.
TL;DR: Spatiotemporal frequency responses were measured at different levels of light adaptation for cat X and Y retinal ganglion cells and interpreted in terms of a Gaussian center-surround model.
Abstract: Spatiotemporal frequency responses were measured at different levels of light adaptation for cat X and Y retinal ganglion cells. Stationary sinusoidal luminance gratings whose contrast was modulated sinusoidally in time or drifting gratings were used as stimuli. Under photopic illumination, when the spatial frequency was held constant at or above its optimum value, an X cell's responsivity was essentially constant as the temporal frequency was changed from 1.5 to 30 Hz. At lower temporal frequencies, responsivity rolled off gradually, and at higher ones it rolled off rapidly. In contrast, when the spatial frequency was held constant at a low value, an X cell's responsivity increased continuously with temporal frequency from a very low value at 0.1 Hz to substantial values at temporal frequencies higher than 30 Hz, from which responsivity rolled off again. Thus, 0 cycles X deg-1 became the optimal spatial frequency above 30 Hz. For Y cells under photopic illumination, the spatiotemporal interaction was even more complex. When the spatial frequency was held constant at or above its optimal value, the temporal frequency range over which responsivity was constant was shorter than that of X cells. At lower spatial frequencies, this range was not appreciably different. As for X cells, 0 cycles X deg-1 was the optimal spatial frequency above 30 Hz. Temporal resolution (defined as the high temporal frequency at which responsivity had fallen to 10 impulses X s-1) for a uniform field was approximately 95 Hz for X cells and approximately 120 Hz for Y cells under photopic illumination. Temporal resolution was lower at lower adaptation levels. The results were interpreted in terms of a Gaussian center-surround model. For X cells, the surround and center strengths were nearly equal at low and moderate temporal frequencies, but the surround strength exceeded the center strength above 30 Hz. Thus, the response to a spatially uniform stimulus at high temporal frequencies was dominated by the surround. In addition, at temporal frequencies above 30 Hz, the center radius increased.
TL;DR: In this paper, the swimming of a flagellar micro-organism by the propagation of helical waves along its flagllum is analyzed by a boundary-element method.
Abstract: The swimming of a flagellar micro-organism by the propagation of helical waves along its flagellum is analysed by a boundary-element method. The method is not restricted to any particular geometry of the organism nor does it assume a specific wave motion for the flagellum. However, only results for an organism with a spherical or ellipsoidal cell body and a helically beating flagellum are presented here.With regard to the flagellum, it is concluded that the optimum helical wave (amplitude α and wavenumber k) has αk ≈ 1 (pitch angle of 45°) and that for the optimum flagellar length L/A = 10 (L being the flagellar length, A being the radius of the assumed spherical cell body) the optimum number of wavelengths Nλ is about 1.5. Furthermore there appears to be no optimal value for the flagellar radius a, with the thinner flagella being favoured. These conclusions show excellent quantitative agreement with those of slender-body theory.For the case of an ellipsoidal cell body, the optimum aspect ratios B/A and C/A of the ellipsoid are about 0.7 and 0.3 respectively; A, B and C are the principal radii of the ellipsoid. These and all of the above conclusions show good qualitative agreement with experimental observations of efficiently swimming micro-organisms.
TL;DR: In this paper, spontaneous Raman scattering has been used to measure the temperature of CH 4 turbulent non-premixed flames using the Rayleigh scattered signal, and the remaining "fluorescence" has been corrected for, using correction curves generated from measurements made in a laminar counterflow CH 4 diffusion flame and a diluted CH 4 N 2 = 1 2 (by vol.) Laminar diffusion flame.
TL;DR: It appears that, within the atopic population, the type of allergen to which the individual is sensitized, the quantity of aeroallergen present in the environment and the degree of atopy, as measured by the number and size of the skin reactions, are all factors that may interact to increase the risk of BHR.
Abstract: Two populations of schoolchildren, one living in an area where the predominant allergens are house dust mites and the other in an area where the predominant allergens are pollens, were studied to investigate in more detail the associations between atopy, bronchial hyperresponsiveness (BHR) and symptoms of asthma. The prevalence of atopy (39%) was the same in both towns but the prevalence of BHR was higher in the inland 'pollen' area (19% vs 15%). Atopic children had an increased risk of having BHR and, to a lesser extent, respiratory symptoms, diagnosed asthma and hay fever. The risk of BHR was further increased in children atopic to both pollens and house dust mites, and in children with a high index of atopy (derived from the number and size of the skin reactions to four allergen groups). In addition, the relationship between atopy and BHR was quantitative in that the severity of BHR increased with the severity of atopy. We conclude that there is not a direct causal relationship between atopy and BHR but there may be a common mechanism involved in their development. It appears that, within the atopic population, the type of allergen to which the individual is sensitized, the quantity of aeroallergen present in the environment and the degree of atopy, as measured by the number and size of the skin reactions, are all factors that may interact to increase the risk of BHR.
TL;DR: Experimental studies in dogs indicate that chondroprotective agents such as semisynthetic sulfated polysaccharides may protect articular cartilage after meniscectomy, and laboratory research suggests that a solution to this problem may be within reach.
Abstract: It is now well established that the meniscus performs a number of roles that are important to the efficient performance of the knee joint. Of particular importance is the recognition of its load-bearing function and its stabilization of the joint during flexion-extension. The compression of the wedge-shaped meniscus during loading is translated into circumferential stresses, and the collagen fiber distribution and orientation is well adapted for this mechanical role. Proteoglycans of the meniscus have structural characteristics in common with those of articular cartilage but do not appear to influence the tensile properties of menisci. With aging and degeneration, compositional changes take place within the meniscus that reduce its ability to transmit tensional stresses, and this contributes to failure. Total meniscectomy is not a benign procedure. Partial excision has less deleterious effects on the joint. Surgical repair of meniscus lesions has now emerged as a procedure of some significance and laboratory research suggests that a solution to this problem may be within reach. Experimental studies in dogs also indicate that chondroprotective agents such as semisynthetic sulfated polysaccharides may protect articular cartilage after meniscectomy.
TL;DR: In this article, specific essential works of plane stress ductile tearing of polyethylenes were obtained from deeply edge-notched tension specimens, with either single or double notches, by extrapolating the straight line relationship between the total specific fracture work and ligament length to zero ligament.
Abstract: The specific essential works of plane stress ductile tearing of several high- and ultrahigh-molecular-weight polyethylenes were obtained from deeply edge-notched tension specimens, with either single or double notches, by extrapolating the straight line relationship between the total specific fracture work and ligament length to zero ligament. Provided the fracture morphologies of the torn ligament are not widely different, the specific essential work (we) is a material property dependent on thickness but independent of specimen geometry. The specific essential fracture work also can be identified with Jc the critical value of the J-integral along a contour immediately bordering the fracture process zone at the crack tip. There is good agreement between the experimental we values and theoretical Jc estimates for these polyethylene materials.
TL;DR: In this article, a corporeal feminism in Australian Feminist Studies: Vol 2, Feminism and the Body, pp 1-16, 1987, Australia Feminist Studies (AFS).
Abstract: (1987) Notes towards a corporeal feminism Australian Feminist Studies: Vol 2, Feminism and the Body, pp 1-16
TL;DR: The physiology and biochemistry of algal calcification are discussed in relation to the above processes and compared to noncalcareous algae.
Abstract: The deposition of CaCO3 by algae (calcification) is a widespread phenomenon and the deposits of either aragonite or calcite may be extra‐, inter‐, or intracellular. This variability in location and crystal isomorph suggests that different calcification mechanisms operate in different algal groups. Despite this difference, all algal calcification systems have some common features. These include the need for a suitable CaCO3‐crystal nucleation mechanism and the stimulation of calcification by photosynthesis. The physiology and biochemistry of algal calcification are discussed in relation to the above processes and compared to noncalcareous algae.
TL;DR: The paucity of data on the natural history of primary pulmonary hypertension, and the observation that some patients awaiting heart-lung transplantation (HLT) appeared to be living longer than expected, led us to analyze the survival data of patients with PPH who had been referred for consideration of HLT.