Showing papers by "La Trobe University published in 1983"
TL;DR: In this paper, a simple and rapid method for the preparation of alditol acetates from monosaccharides is described, which can be performed in a single tube without transfers or evaporations.
1,880 citations
TL;DR: The pineal gland hormone melatonin may play a role in synchronization of rat circadian rhythms, and the time of day of melatonin administration is crucial in pharmacological experiments.
Abstract: The pineal gland hormone melatonin may play a role in synchronization of rat circadian rhythms. Free-running activity rhythms of the rat were entrained by a daily melatonin injection, with entrainment occurring when the onset of activity coincided with the time of daily injections. When injections were stopped, activity rhythms became free-running again. Thus in pharmacological experiments, the time of day of melatonin administration is crucial.
552 citations
513 citations
TL;DR: Water-soluble (1→3),(1→4)-β-d -glucans isolated from barleys grown in Australia and the UK were depolymerised using a purified ( 1→3) β-d-glucan hydrolase (EC 3.2.73).
225 citations
TL;DR: In all preparations caffeine was found to reversibly shift the relation between steady-state force and free [Ca2+] toward lower free [Cardiac and slow-twitch] in a dose dependent manner, causing an increase in apparent Ca2+ sensitivity.
Abstract: Skinned fibres prepared by mechanical and/or chemical means from cardiac and skeletal muscles of the rat were activated in solution strongly buffered for Ca2+ (with 50 mM EGTA) in the absence or presence of caffeine 5–40 mM. In all preparations caffeine was found to reversibly shift the relation between steady-state force and free [Ca2+] toward lower free [Ca2+] in a dose dependent manner. This increase in apparent Ca2+ sensitivity was not antagonized by procaine and was the same, within each muscle type, irrespective of the manner in which the skinned fibre was prepared, and consequently the degree to which it retained cellular membranes. The effect was more pronounced in cardiac and slow-twitch than in fast-twitch, myofibrillar preparations. At equivalent concentrations theophylline mimicked this effect of caffeine in all preparations, however, addition of exogenous cyclic AMP neither mimicked nor modified, in any way, the effect. Maximum Ca2+-activated force production was not affected by caffeine below 20 mM but was depressed by concentrations of 20 mM and above. The increase in apparent Ca2+ sensitivity produced by caffeine can not be the result of a mobilization of some cellular store of Ca2+ but must arise from a direct effect of caffeine on the myofilaments which leads to a change in the apparent affinity constant of the force controlling sites for Ca2+.
187 citations
Book•
01 Jan 1983TL;DR: A comparative study of settler societies in Argentina, Chile, Uruguay, South Africa, Australia, and New Zealand is presented in this paper, which describes the economic, social, and political changes which occurred during the nineteenth century.
Abstract: This book is a comparative study of settler societies in Argentina, Chile, Uruguay, South Africa, Australia, and New Zealand. It describes the economic, social, and political changes which occurred during the nineteenth century.
185 citations
TL;DR: In this article, neutral density screens were used to reduce the level of irradiance available to an intertidal population of Heterozostera tasmanica den Hartog in Western Port, Victoria, Australia.
147 citations
TL;DR: It is demonstrated that epiphyte biomass can accumulate fast enough to shade H. tasmanica leaves and significantly reduce the time (to less than one half of the leaf life span) in which positive net photosynthesis of the Leaf blade is possible.
144 citations
TL;DR: The specificity of the dye-polysaccharide interaction enabled the location of (1→3),(1→4)-β- D -glucan to be identified as being in the endosperm cell walls and inner walls of aleurone cells in oats, barley and wheat.
126 citations
TL;DR: Vanzetti and Kennedy's comment on our earlier paper as mentioned in this paper gives us the opportunity to clarify the differences in the models, to present a generalization of the analysis that includes their results as well as ours as special cases, and then to point out some salient features of our model that seem to have been unnoticed by them.
Abstract: Vanzetti and Kennedy's (herein VK) comment on our earlier paper (Sarris and Freebairn) gives us the opportunity, first, to clarify the differences in the models, to present a generalization of the analysis that includes their results as well as ours as special cases, and then to point out some salient features of our model that seem to have been unnoticed by them. Consider our model of a homogenous commodity produced, consumed and traded by n countries, which are characterized by the following linear demand and supply curves (notation follows VK except that we maintain the additive random variables and hence keep the time subscript).
122 citations
TL;DR: Experiments were performed to determine whether for mice pre-injected with pristane there is an optimum interval before injection of hybridomas in order to maximize ascites fluid formation and yield of monoclonal antibodies.
TL;DR: Any mechanism proposed for the biosynthesis of the molecule should explain this apparently random distribution of cellotriosyl and cellotetraosyl residues as well as the presence, in relatively low frequency, of blocks of up to 10 or more adjacent (1→4)-linkages.
TL;DR: A more general involvement of the dopaminergic pathways of the NAS in schedule-induced behaviors and in concomitant plasma corticosterone changes is shown.
Abstract: In a series of four experiments the relationship between 6-OHDA lesions of the nucleus accumbens septum (NAS), schedule-induced behaviors and plasma corticosterone levels was explored. Data from the first experiment show a significant decrease in water intake during a scheduled food delivery test hour for 6-OHDA lesioned groups of rats compared with sham or non-lesioned groups of rats, while during the remaining 23 hours of the day water intake was the same for 6-OHDA lesioned and sham lesioned groups. In a second experiment similar decreases in schedule-induced wheelrunning were observed for 6-OHDA lesioned rats when compared with sham lesioned rats. Data from a third experiment showed significant increases in plasma corticosterone levels of rats in the presence of a scheduled food delivery compared with rats given non-scheduled food. In a fourth experiment it was shown that 6-OHDA lesions of the NAS abolish this increase of corticosterone levels in rats on a food delivery schedule. These data extend the findings of Robbins and Koob [19] and show a more general involvement of the dopaminergic pathways of the NAS in schedule-induced behaviors and in concomitant plasma corticosterone changes.
TL;DR: In this paper, the age of granulite facios metamorphism has been defined by coupling whole-rock Sm-Nd analyses of the principal members of the South Harris Igneous Complex, with Sm-nd mineral isochrons on two anothositic gabbros.
Abstract: Sm-Nd geochronology may be used to bracket the age of metamorphism in rocks which are difficult to date by other methods. By coupling whole rock Sm-Nd analyses of the principal members of the South Harris Igneous Complex, with Sm-Nd mineral isochrons on two anothositic gabbros, the age of granulite facios metamorphism has been defined. Whole rock analyses of three pairs of closely spaced samples of the anorthosite give consistent ages averaging 2.18±0.06 Gyr, but in general the data from the anorthosite do not define an isochron as a result of variable contamination of the evolving magma chamber. Whole rock data on the tonalite indicate that it is younger than 2.06 Gyr; its mean TCHUR age is 1.86±0.05 Gyr. Garnet-pyroxene-amphibole-plagioclase mineral isochrons on two anorthosite samples give identical 1.87±0.04 Gyr ages which date cooling after the high pressure granulite facies metamorphism. Together with the tonalite whole rock data this defines the age of that metamorphism and confirms Dearnley's original assignment of an early Laxfordian age.
TL;DR: The diversity of Australia's brachyopoids, including the presence of the most primitive and earliest-known members of each of the included families, suggests that the superfamily originated in Australia.
Abstract: Remains of a fossil amphibian have been recovered from an ironstone layer in the Upper Evergreen Formation, dated as late Liassic, of southeast Queensland. Extraction of the skeleton from the very hard matrix has presented a number of problems which are discussed. The find is an almost complete skull and mandible connected to an articulated postcranial skeleton which is missing only some ribs, the right hind leg and the distal portions of the other limbs and tail. The remains are those of a temnospondyl labyrinthodont described as a new genus and species of the family Chigutisauridae. The new form is notable for its very large size (total length estimated to be in excess of 2.5 m), relatively large marginal dentition, with unique lance-shaped tooth tips, the presence of minute denticles associated with the palate and mandible, a well developed atlas showing a strong link with the axis, neorhachitomous vertebrae that lack ossified pleurocentra and have low, heavily built neural spines, a neck region and a narrow dermal pectoral girdle associated with unreduced limbs. The discovery of this chigutisaur provides the first unequivocal evidence that labyrinthodonts survived beyond the end of the Triassic. The status of two previously described doubtful Jurassic forms is reviewed. Austropelor Longman, 1941, from the Early Jurassic Marburg Sandstone of southeast Queensland, is confirmed as a fragment of temnospondyl lower jaw, probably attributable to the superfamily Brachyopoidea, and there is no longer any reason to consider the earlier suggestion that it is a reworked Triassic fossil. Cyrtura Jaekel, 1904, from the Late Jurassic Solnhofen Shale of Germany, is considered not to be a labyrinthodont, but its exact relationships are uncertain. The unsatisfactory nature of the higher taxonomy of the Temnospondyli is noted. The superfamily Brachyopoidea is reviewed and the family Kourerpetontidae is removed from it, membership of the superfamily thereby being restricted to the Brachyopidae (Late Permian to Middle Triassic) and Chigutisauridae (Early Triassic to Early Jurassic). Diagnoses for the superfamily and its two included families are provided. The relationships of the better characterized members of the two families are examined and a phylogeny based on shared derived character states is proposed. The analysis of relationships indicates that Brachyops allos Howie, 1972 shares few of the characters diagnostic of the type of Brachyops (B. laticeps Owen, 1855), and a new genus is proposed. The diversity of Australia's brachyopoids, including the presence of the most primitive and earliest-known members of each of the included families, suggests that the superfamily originated in Australia.
TL;DR: Kinetic studies on the iron‐treated enzyme indicate an ‘alcohol activation’ phenomenon, which may have physiological relevance in overcoming product inhibition during fermentation.
TL;DR: A data-based algorithm which chooses the window width for a kernel estimator of the density at a point and the performance of the resulting window width is evaluated using Monte Carlo methods.
TL;DR: The purpose of this paper is to give an introduction and overview to document analysis, since it has rarely been discussed in the literature.
TL;DR: In this paper, the molecular weight and solution properties of a (1→3), (1/4)-β-d -glucan from Australian grown barley (cv. Clipper) are compared with a commercially available preparation.
TL;DR: The genetic analysis indicates that social organization has the potential to restrict gene flow within local populations of house mice and indicated a strong association between social dominance and reproductive success.
Abstract: The social behavior and reproductive success of individual house mice were monitored in an enclosure. The subjects were obtained from natural populations and were selected on the basis of the genotype at five genetic loci. Male mice formed a three-tiered social hierarchy. In two replicate experiments α-dominant males formed two well defined territories which they constantly patrolled and strongly defended for periods of 120–200 days. The subdominant and subordinate males resided along the periphery of the enclosure and were most active when the dominant males were resting. In the second experiment the subdominant males were able to establish territories after a period of 140 days. Reproductive females generally confined their movements to within the territorial boundaries of a single α-dominant male. Once a female occupied a nest box within a particular male's territory, she rarely entered the territory of the other α-dominant male. Genetic analysis of five segregating loci enabled ascertainment of the paternity of 13 of the litters born and indicated a strong association between social dominance and reproductive success. There was only one instance of gene flow between social breeding units. The genetic analysis therefore indicates that social organization has the potential to restrict gene flow within local populations of house mice.
TL;DR: Standing crop, density and leaf growth rate of Heterozostera tasmanica (Martens ex Aschers.) den Hartog along with light, temperature, nutrient and sediment characteristics were determined monthly for fifteen months at three study sites in Western Port and one site in Port Phillip Bay, Australia.
TL;DR: The name Lithothamnium Philippi has been widely and persistently applied to a taxon not including its nomenclatural type and it therefore must be rejected under Article 69 of the International Code of Botanical Nomenclature.
Abstract: Critical studies of the original collections upon which Lithothamnium Philippi (Corallinaceae, Rhodophyta) is based have revealed that none of the five species included in the initial presentation conforms to any modern concept of the genus. Two species are referrable to Amphiroa and one each to Goniolithon, Lithophyllum and Pseudolithophyllum. Since 1897, the name Lithothamnium Philippi has been widely and persistently applied to a taxon not including its nomenclatural type and it therefore must be rejected under Article 69 of the International Code of Botanical Nomenclature. After considering various alternative solutions to the problem of a replacement for one of the more widely used algal names in the botanical and geological literature, it is proposed to conserve Lithothamnion Heydrich, based on the selected lectotype species L. muelleri Lenormand ex Rosanoff, against Lithothamnium Philippi. Detailed morphological-anatomical accounts of specimens in the type collections are presented along with relev...
TL;DR: It is postulate that hormones from both adrenal medulla and cortex are involved in the retention of information post-stress, and that these hormones act directly on the CNS rather than via the pituitary, since the response to adrenalectomy is not dependent on the presence of the pituitsary gland.
TL;DR: A one-parameter group on evolution space which permutes the classical trajectories of a Lagrangian system is called a dynamical symmetry as discussed by the authors, and the theory is illustrated with a presentation of results for the classical Kepler problem.
Abstract: A one-parameter group on evolution space which permutes the classical trajectories of a Lagrangian system is called a dynamical symmetry. Following a review of the modern approach to the “symmetry-conservation law” duality an attempt is made to classify such invariance groups according to the induced transformation of the Cartan form. This attempt is fairly successful inasmuch as the important cases of Lie, Noether and Cartan symmetries can be distinguished. The theory is illustrated with a presentation of results for the classical Kepler problem.
TL;DR: This method was used for the simultaneous detection of neutral and aminosugars in acid hydrolysates of chitin and the glycoproteins, ovalbumin and peroxidase.
TL;DR: The polybrene mediated adsorption was found to be inhibited by the addition of tri-sodium citrate to the culture medium, suggesting the involvement of electrostatic forces, which was supported by the demonstration of temperature independence of the polyBrene mediated interaction.
Abstract: Polybrene was shown to enhance the adsorption of simian sarcoma virus-simian sarcoma associated virus complex (SSV-1/SSAV-1) and baboon endogenous virus (BaEV) onto cells in culture. A 16- to 18-fold increased adsorption of both viruses occurred at 8 µg/ml polybrene within one hour after infection. The polybrene mediated adsorption was found to be inhibited by the addition of tri-sodium citrate to the culture medium, suggesting the involvement of electrostatic forces. This contention was further supported by the demonstration of temperature independence of the polybrene mediated interaction.