Showing papers by "University of Western Australia published in 1978"
TL;DR: In this paper, a rating response mechanism for ordered categories, which is related to the traditional threshold formulation but distinctively different from it, is formulated, in which subject and item parameters are derived in terms of thresholds on a latent continuum and discriminations at the thresholds.
Abstract: A rating response mechanism for ordered categories, which is related to the traditional threshold formulation but distinctively different from it, is formulated. In addition to the subject and item parameters two other sets of parameters, which can be interpreted in terms of thresholds on a latent continuum and discriminations at the thresholds, are obtained. These parameters are identified with the category coefficients and the scoring function of the Rasch model for polychotomous responses in which the latent trait is assumed uni-dimensional. In the case where the threshold discriminations are equal, the scoring of successive categories by the familiar assignment of successive integers is justified. In the case where distances between thresholds are also equal, a simple pattern of category coefficients is shown to follow.
2,709 citations
TL;DR: In this paper, a latent trait measurement model in which ordered response categories are both parameterized and scored with successive integers is investigated and applied to a summated rating or Likert questionnaire.
Abstract: A latent trait measurement model in which ordered response categories are both parameterized and scored with successive integers is investigated and applied to a summated rating or Likert ques tionnaire In addition to each category, each item of the questionnaire and each subject are para meterized in the model; and maximum likelihood estimates for these parameters are derived Among the features of the model which make it attractive for applications to Likert questionnaires is that the total score is a sufficient statistic for a subject's at titude measure Thus, the model provides a formal ization of a familiar and practical procedure for measuring attitudes
403 citations
TL;DR: A theory of triangular arrays, called renewal arrays, which have arithmetic properties similar to those of Pascal's triangle are developed, and the Lagrange inversion formula has an important place in this theory and there are several examples of renewal arrays of combinatorial interest.
159 citations
TL;DR: In this paper, a generalisation of Rasch's simple logistic model for dichotomously scored achievement items is presented, which has consequences for both statement scaling and person measurement.
Abstract: The statement scaling emphasis associated with the Thurstone tradition for the study of attitude provides no direct consequence for attitude measurement, while conversely, the attitude measurement emphasis in the Likert tradition provides no direct consequence for statement scaling. Both aspects of the study of attitude are unified by a generalisation of Rasch's simple logistic model for dichotomously scored achievement items. The generalized model caters for the response category system of attitude questionnaires constructed and scored in the Likert tradition, but because both statements and persons are parameterised, the model has consequences for both statement scaling and person measurement. As with the simple logistic model, the two sets of parameter estimates, in this case those of the statements and of the persons, are independent of each other. An illustration involving attitudes to the professional roles of teachers is provided.
155 citations
TL;DR: The ureides, allantoin and allantoic acid, represented major fractions of the soluble nitrogen pool of nodulated plants of cowpea throughout vegetative and reproductive growth and exported from nodule to shoot via the xylem.
Abstract: The ureides, allantoin and allantoic acid, represented major fractions of the soluble nitrogen pool of nodulated plants of cowpea (Vigna unguiculata [L.] Walp. cv. Caloona) throughout vegetative and reproductive growth. Stem and petioles were the principal sites of ureide accumulation, especially in early fruiting.Labeling studies using (14)CO(2) and (15)N(2) and incubation periods of 25 to 245 minutes indicated that synthesis of allantoin and allantoic acid in root nodules involved currently delivered photosynthate and recently fixed N, and that the ureides were exported from nodule to shoot via the xylem. From 60 to 80% of xylem-borne N consisted of ureides; the remainder was glutamine, asparagine, and amino acids. Allantoin predominated in the soluble N fraction of nodules and fruits, allantoin and allantoic acid were present in approximately equal proportions in xylem exudate, stems, and petioles.Extracts of the plant tissue fraction of nitrogen-fixing cowpea nodules contained glutamate synthase (EC 2.6.1.53) and glutamine synthetase (EC 6.3.1.2), but little activity of glutamate dehydrogenase (EC 1.4.1.3). High levels of uricase (EC 1.7.3.3) and allantoinase (EC 3.5.2.5) were also detected. Allantoinase but little uricase was found in extracts of leaflets, pods, and seeds.Balance sheets were constructed for production, storage, and utilization of ureide N during growth. Virtually all (average 92%) of the ureides exported from roots was metabolized on entering the shoot, the compounds being presumably used as N sources for protein synthesis.
145 citations
TL;DR: Differences in the growth of subterranean clover when limited by phosphorus supply were related to the rate of mycorrhiza development, and two of the introduced endophytes, isolates of Glomus monosporus and G. fasciculatus, differed in their ability to increase growth and phosphorus content of underground clover.
Abstract: SUMMARY
Three vesicular arbuscular (VA) endophytes differed in their ability to increase the growth of subterranean clover when introduced into a freshly collected field soil. Four indigenous endophytes infected the roots in both the control and inoculated treatments. Two of the introduced endophytes, isolates of Glomus monosporus, differed in their ability to increase growth and phosphorus content of subterranean clover. These endophytes were both superior to the third introduced endophyte, G. fasciculatus.
Differences in the growth of subterranean clover when limited by phosphorus supply were related to the rate of mycorrhiza development. Inoculation of soil with the three introduced endophytes did not reduce initial infection by the four indigenous endophytes. Mycorrhizas formed by G. monosporus and G. fasciculatus were distinguished from those formed by indigenous endophytes on the basis of morphology.
Plants inoculated with isolates of G. monosporus had a greater proportion of their dry weight and phosphorus content in the tops than plants inoculated with G. fasciculatus or the control plants.
141 citations
TL;DR: In this article, a Lagrangian model of the dynamics of a reservoir is presented, which utilizes new formulas to describe both the inflow and outflow dynamics of both the mixed and non-mixed layers.
Abstract: A Lagrangian one-dimensional model of the dynamics of a reservoir is presented. The model utilizes new formulas to describe the dynamics of both the inflow and outflow. In addition, recent advances pioneered in the oceanographic literature have been modified and applied to the dynamics of the mixed layer. Finally, a new model is proposed for deep hypolimnionic mixing. The model so constructed contains only four universal constants. Data from one complete annual cycle of the salinity and temperature distribution from a Western Australian reservoir are used to calibrate the model.
135 citations
TL;DR: When the logistic function is substituted for the normal, Thurstone's Case V specialization of the law of comparative judgment for paired comparison responses gives an identical equation for the especial case as discussed by the authors.
Abstract: When the logistic function is substituted for the normal, Thurstone's Case V specialization of the law of comparative judgment for paired comparison responses gives an identical equation for the es...
134 citations
TL;DR: In this article, the authors suggest that metamorphism and deformation of greenstone sequences and the evolution of intrusive granitoids in the Eastern Goldfields Province, Yilgarn Block, were related to a widespread and integrated tectonic event in the time interval 2700-2600 m.y.
126 citations
TL;DR: The magnetite particles were present in a range of sizes and morphologies as mentioned in this paper, and the incorporation of small amounts (2+ and its ability to exhibit the Jahn-Teller effect and the larger ionic radii of Mn 2+ and Cd 2+ may be responsible for their non-uniform distribution in the magnetite crystals.
125 citations
01 Jan 1978
TL;DR: In this article, the steady plane periodic waves on the surface of an ideal liquid flowing above a horizontal bottom were studied and it was shown that, at each fixed Q and L, there exist wave solutions for each value of qc strictly between c and zero.
Abstract: This paper concerns steady plane periodic waves on the surface of an ideal liquid flowing above a horizontal bottom. The flow is irrotational. The volume flow rate is denoted by Q, the velocity potential by o, the period in o of the waves by 2L, and the maximum angle of inclination between the tangent to the surface and the horizontal by θm.Krasovskii (12) established that, at each fixed Q and L, there exist wave solutions for each value of θm strictly between zero and ⅙π. We establish that, at each fixed Q and L, there exist wave solutions for each value of qc strictly between c and zero. Here qc is the flow speed at the crest, andwhere g is the acceleration due to gravity. Krasovskii's set of solutions is included in the set that we obtain.
TL;DR: In this article, a new assemblage of microfossils from a ∼3,500 Myr BP silicified shallow-water to supratidal carbonate sequence of the Warrawoona Group at North Pole, Western Australia is described.
Abstract: THE oldest documented microfossils are from the ∼3,300 Myr BP Onverwacht Group of South Africa6–8 Here, we discuss the occurrence of a new assemblage of microfossils from a ∼3,500 Myr BP silicified shallow-water to supratidal carbonate sequence of the Warrawoona Group at North Pole, Western Australia Five morphologies of carbonaceous spheroids are recognised, including some with splits, some with tetragonal tetrad form and others with groups of up to four individuals Their morphology is very similar to microfossils from the Onverwacht group of South Africa, and statistical tests of size distribution support a biogenic origin This occurrence suggests that evidence for early Archaean life may be more widespread than generally thought
TL;DR: The concept of the two compartment and three compartment models for drug disposition are introduced and developed to demonstrate the mathematical models which may be derived to describe the kinetics of drug distribution and elimination.
Abstract: This series of two review articles deals with general aspects of the mechanisms which govern absorption and distribution of drugs within the body, and the kinetics of drug metabolism and excretion. Emphasis is given to the verification of pharmacokinetic principles in domestic animals, and the clinical applications which proceed therefrom. In the first part, the concept of the two compartment and three compartment models for drug disposition are introduced and developed to demonstrate the mathematical models which may be derived to describe the kinetics of drug distribution and elimination. In the second part bioavailability and drug dosage will be considered.
TL;DR: In this article, the authors summarise the petrographic evidence, concentrating on recent data from North Pole, and report stable isotopic results for barite and associated sulphides which provide corroborative evidence for the environments of formation of these deposits.
Abstract: SIGNIFICANT Archaean bedded sulphate deposits have been described only from the Pilbara Block (Western Australia)1,2, the Barberton Mountainland (South Africa)3–6 and southern India7. These are all barite deposits, but there is petrographic evidence suggesting replacement of original evaporitic gypsum in the North Pole (Pilbara) and Barberton deposits. This contrasts with the apparent volcanogenic deposition of barite in the relatively sulphide-rich Big Stubby prospect (Pilbara). This letter summarises the petrographic evidence, concentrating on recent data from North Pole, and reports stable isotopic results for barite and associated sulphides which provide corroborative evidence for the environments of formation of these deposits. Some implications concerning the early hydrosphere, atmosphere and biosphere are outlined.
TL;DR: Findings show that pentobarbitone influences synaptic curvature, with a marked increase in curvature negativity over the 0-80 mg/kg dose range and a decrease in negativity at higher dose levels, supporting a membrane redistribution hypothesis.
TL;DR: Adult rat liver parenchymal cells, maintained in primary monolayer culture on floating collagen gels, were used for studies on the hormonal regulation of phosphoenolpyruvate carboxykinse and induction by glucagon was shown to be dose-dependent.
Abstract: Adult rat liver parenchymal cells, maintained in primary monolayer culture on floating collagen gels, were used for studies on the hormonal regulation of phosphoenolyruvate carboxykinse. In cells maintained in a defined, serum-free medium containing insulin but no other hormones, phosphoenolpyruvate carboxykinse activity expressed on the basis of cell DNA content decreased over 3 days in culture with a half-life of 9–10 h. Treatment of cells with glucagon or N6, O2′-dibutyryladenosine 3′:5′ monophosphate (Bt2-cAMP) caused an increase in enxyme activity up to 4-fold higher than in untreated cells. There was little or no response during the first 24 h of culture but addition of either glucagon or Bt2-cAMP after this period resulted in significant enzyme induction within 3 h. When cells were maintained for 2–3 days after attachment directly to palstic culture dishes rather than to collagen gels, similar inductive responses to glucagon or Bt2-cAMP were observed. Induction by glucagon was shown to be dose-dependent; a significant response was evident at 0.1 nM gucagon.
Addition of epinephrine to cultured cells at concentration between 10 nM to 0.1 mM was without effect on phosphoenolpyruvate carboxykinase. Induction by Bt2-cAMP was completely prevented by the simultaneous addition of actinomycin D (0.2 μg/ml) or cordycepin (10 μg/ml) suggesting that the nucletide acts or transcription to increase phosphoenolpyruvate carboxykinase synthesis.
TL;DR: Quantitative analysis of the lymphocyte infiltration at the periphery of colorectal carcinomata has revealed a statistically significant difference, p < 0.001, in the distribution associated with Duke B compared with Dukes C tumors of moderate differentiation.
Abstract: Quantitative analysis of the lymphocyte infiltration at the periphery of colorectal carcinomata has revealed a statistically significant difference, p less than 0.001, in the distribution associated with Dukes B compared with Dukes C tumors of moderate differentiation.
TL;DR: The major constituents of propolis collected in Western Australia have been isolated and identified as pterostilbene (5), xanthorrhoeol (6), sakuranetin (2) and pinostrobin (1).
Abstract: The major constituents of propolis collected in Western Australia have been isolated and identified as pterostilbene (5), xanthorrhoeol (6), sakuranetin (2) and pinostrobin (1).
TL;DR: Choroidal malignant melanomas in nine patients were treated with proton beam irradiation at the Harvard Cyclotron Laboratory, Cambridge, Mass, with an average of 12 months, and different signs of tumor regression have been noted.
Abstract: • Choroidal malignant melanomas in nine patients were treated with proton beam irradiation at the Harvard Cyclotron Laboratory, Cambridge, Mass. Each patient received five proton beam treatments in eight to ten days, totaling 4,730 to 8,570 rads at the tumor. No complications occurred during the treatment or followup period, which, at the time of this writing, ranges from one to 24 months, with an average of 12 months. No further growth of the tumor has been observed in any patient. Different signs of tumor regression have been noted. Resolution of the serous retinal detachments that accompanied some tumors is the earliest finding. Pigment changes over the surface of the tumor and adjacent pigment epithelium is a usual initial tumor response. Fluorescein angiography initially showed decreased leakage of dye; later, destruction of the tumor's vasculature and elimination of fluorescein leakage became evident. Only large choroidal vessels remained patent. Ultrasonography revealed decreased height of the tumors postirradiation, and the radioactive phosphorus ( 32 P) uptake test, repeated in one patient, turned negative on postirradiation measurements.
TL;DR: Epidermal cells of Posidonia australis Hook have no cell wall ingrowth but the porous cuticle may facilitate nutrient absorption and Numerous plasmodesmata are present between epidermis and mesophyll cells suggesting that photosynthates can be transported by a symplastic route.
TL;DR: In this paper, the structures of pyrochlore, W 3 Fe 3 C, Sb 2 O 3 (cub), KTaWO 6 ·H 2 O, RbNbTeO 6, and Mg 3 Cr 2 Al 18 are discussed.
TL;DR: It seemed likely from the smaller effect of supplemented choline and from the fatty acid composition of lymph phosphatidylcholine that the essential requirement was a supply of absorbed lysophosphatidycholine for rapid reacylation to phosphatidscholine, but it was concluded that a luminal supply of 1-palmitoyl lysphosph atidyl choline was not essential.
TL;DR: Autoradiographic experiments using 3H-thymidine provide conclusive evidence that both denervation and tenotomy stimulate cell proliferation in skeletal muscle and it is suggested that the increased numbers of labelled muscle nuclei are likely to be the result of mitotic activity in muscle satellite cells.
Abstract: Autoradiographic experiments using 3H-thymidine were designed to analyse cell proliferation which occurs in skeletal muscle after denervation and after tenotomy In mouse tibialis anterior and tongue muscles during the first 24 h after denervation or tenotomy labelling levels were low and did not differ significantly from sham operated control muscles By 48 h after denervation and tenotomy of tibialis anterior muscles, increased levels of labelling occurred in both muscle and connective tissue nuclei Daily pulse labelling for 7 days after denervation produced a labelling level which was 8 times that of sham operated controls, 25–30% of the total nuclear population being labelled Denervated muscles had twice the level of labelling compared to tenotomised muscles These results provide conclusive evidence that both denervation and tenotomy stimulate cell proliferation in skeletal muscle and it is suggested that the increased numbers of labelled muscle nuclei are likely to be the result of mitotic activity in muscle satellite cells
TL;DR: The 60-item General Health Questionnaire was completed by 90% of 4798 patients aged 15--69 years who consulted, on one day, the general practitioners of 97% of practices in the Perth Statistical Division, and the demographic pattern of morbidity was compared with that found in a probability sample of 2324 community residents drawn from the same population at risk.
Abstract: The 60-item General Health Questionnaire was completed by 90% of 4798 patients aged 15--69 years who consulted, on one day, the general practitioners of 97% of practices in the Perth Statistical Division. A point prevalence rate of minor psychiatric morbidity in various demographic groups was calculated in terms of the population at risk. The demographic pattern of morbidity was compared with that found in a probability sample of 2324 community residents drawn from the same population at risk, and surveyed at the same time using the same time using the same screening instrument. Widowed persons, British-born men who had recently migrated to Australia, and lower-social-class men with minor psychiatric morbidity were under-represented in general practice. Elderly men and women in upper-class occupations with minor psychiatric morbidity were over-represented in general practice. These differences, unlike others that were found, could not be explained by differing consulting habits or by differing completion rates of the screening instrument.
TL;DR: New evidence from the passerine faunas of islands off Southwestern Australia agrees with the hypothesis that the passerines of Australian and New Zealand islands are impoverished because most passerine species are poor colonizers.
Abstract: New evidence from the passerine faunas of islands off Southwestern Australia agrees with the hypothesis that the passerine faunas of Australian and New Zealand islands are impoverished because most passerine species are poor colonizers. Dispersal of landbirds onto Carnac Island near Perth was infrequent, and many of those species that arrived were represented by single birds. Comparison of similarly structured island and mainland habitats showed that island habitats still have fewer passerine bird species than mainland habitats. Island bird faunas are more stable over short periods of time than over long periods; this is contrary to island avifaunas in the Northern Hemisphere.
TL;DR: It is confirmed the existence of such a percussive system in two species of Hecatesia, and two patterns of sound corresponding to the respective flight behaviour of the two species are revealed.
Abstract: DARWIN1 described the sound made by the forewings of the nymphalid Ageronia feronia as a click of a spring catch on a toothed wheel. Descriptions of the sounds produced by the Agarasidae, which have similarly modified forewings, have repeatedly invoked the rubbing of either the antennae or foretibia on the ribbed forewing2,3. Nicholson4 suggested that the production of sound in the whistling moth Hecatesia was percussive, with the knobs of each forewing (castanets) striking each other at the top of the flight stroke. I have confirmed the existence of such a percussive system in two species of Hecatesia. Recordings of H. exultans Walker and H. thyridion Feisthamel from the coastal sand plain of Western Australia revealed two patterns of sound corresponding to the respective flight behaviour of the two species.
TL;DR: Rhizome branching of Posidonia australis Hook.
TL;DR: The concept of sector stability is introduced in this paper, where a partially feasible equilibrium is sector-stable if every solution of the system which begins in a nonnegative neighborhood remains in the same or a larger nonnegative neighbourhood for all finite values of t and converges to the steady state as t → ∞.
Abstract: By definition a partially feasible equilibrium is sector-stable if every solution of the system which begins in a nonnegative neighborhood remains in the same or a larger nonnegative neighborhood for all finite values of t and converges to the steady state as t →∞. It is argued that the concept of sector stability is important in the analysis of a complex ecosystem model. A nontrivial mathematical criterion is given for the total system property which states that the self-regulating intraspecific interactions are stronger than the interspecific interactions. This total system property ensures global stability or global sector stability in a model. It follows that such a model can withstand a wide range of realistic perturbations of its initial state.
TL;DR: The results support the proposal that the relative concentration of insulin and glucagon in the blood regulate the adenosine 3′:5′-monophosphate concentration and thus enzyme induction in the liver of the perinatal rat, but changes in corticosterone concentration are not consistent with the view that steroids are a primary signal for tyrosine sminotransferase induciton in the newborn rat.
Abstract: This report describes some hormonal changes occuring in the rat during the last 3 days of gestation and the first 6 h after surgical deliversy on days 20–22uu ofgestation. In the foetus, the concentration of glucagon increased 2-fold and that of insulin decreaed from 4.7 to 3.5 ng/ml between days 21 and 22. Consequently the insulin/glucagon molar ratio decreased from 15.6 on day 21 to 5.9 on day 22. After delivery on dasys 21 and 22 of gestation plama glucagon concentration increased 2-fold and reeached a maximim at 30 min after birth. In addition, the concentration of serum insulin decreased to about 50% of the foetal values by 30 min post partum. Consequentaly the insulin/glucagon ratio decreased to a minimum 30 min after delivery. There was no sinificant change in the concentration of total, that bound to corticosteroid-binding globulin and free corticosterone in the plasma nor in the concentration of liver corticosterone for 6 h after delivery on day 22 of gestation. Only free plasma corticosterone concentration increased after delivery on day 21 and peaked one hour after birth. The concentration of both pancreatic hommones and corticosterone showed a different development pattern after premauature delivery on day 20 of gestatin. Plasma glucagon increased and plasma insulin decreased for 2 h. Consequentaly the insulin/glucagon ratio decreased from 8.8 at birth to 2.4 at 2 h post partum. The concentration liver corticosterone as well as total, bound and free corticosterone in the plsma incrreased to maximal levels within 1–2 h ofdelivery. The results support the proposal that the relative concentration of insulin and glucagon in the blood regulate the adenosine 3′:5′-monophosphate concentration and thus enzyme induction in the liver of the perinatal rat. However, the changes in corticosterone concentration wer not consistent with the view that steroids are a primary signal for tyrosine sminotransferase induciton in the newborn rat.