Showing papers by "University of Western Australia published in 1975"
TL;DR: In vitro activity was up to 5 mumoles of aspartate formed per hour per gram fresh weight at the apparent Km(Asn) value of 10 mM, and this more than accounted for the estimated rates of asparagine utilization in vivo.
Abstract: Asparagine accounted for 50 to 70% of the nitrogen carried in translocatory channels serving fruit and seed of white lupin (Lupinus albus L.). Rates of supply of the amide always greatly exceeded its incorporation as such into protein. An asparaginase (l-asparagine amido hydrolase EC 3.5.1.1) was demonstrated in crude extracts of seeds. In vitro activity was up to 5 mumoles of aspartate formed per hour per gram fresh weight at the apparent Km(Asn) value of 10 mM, and this more than accounted for the estimated rates of asparagine utilization in vivo. Asparaginase activity per seed increased 10-fold in the period 5 to 7 weeks after anthesis, coinciding with early stages of storage protein synthesis in the cotyledons.Double labeled ((14)C (U), (15)N (amide)) asparagine was fed to fruiting shoots through the transpiration steram. Fruit phloem sap analysis indicated that virtually all of the label was translocated to seeds in the form of asparagine. In young seeds (15)N from asparagine breakdown was traced to the ammonia, glutamine, and alanine of endospermic fluid, the (14)C appearing mainly in nonamino compounds. In the cotyledon-filling stage the C and N of asparagine was contributed to a variety of amino acid residues of protein.
164 citations
157 citations
TL;DR: This work has found that at least one strain of Rhizobium will do so when cultured alone on certain media and confirmed the ability of legume callus cultures to fix nitrogen.
Abstract: ASSOCIATIONS between legume callus cultures and Rhizobium have been shown to fix nitrogen1–6; we have found that at least one strain of Rhizobium will do so when cultured alone on certain media.
138 citations
TL;DR: Increased nitrate supply to roots led to increased amino acid levels in xylem and phloem but did not alter markedly the balance between individual amino acids.
Abstract: Comparisons were made of the levels of various solutes in xylem (tracheal) sap and fruit tip phloem sap of Lupinus albus (L.) and Spartium junceum (L.). Sucrose was present at high concentration (up to 220 mg ml-1) in phloem but was absent from xylem whereas nitrate was detected in xylem (up to 0.14 mg ml-1) but not in phloem. Total amino acids reached 0.5–2.5 mg ml-1 (in xylem) versus 16–40 mg ml-1 in phloem. Phloem: xylem concentration ratios for mineral nutrients (K, Na, Mg, Ca, Fe, Zn, Mn, Cu) spanned the range 0.7 to 20, the ratios generally reflecting an element's phloem mobility and its availability to the xylem from the roots.
134 citations
TL;DR: There were few differences due to breed, age of ewe, nutrition, climate or location in the behaviour of the ewe before and during parturition, but fewer Southdowns and Merinos pawed the ground than ewes of other breeds.
105 citations
01 Jan 1975
TL;DR: The output of research in this area has continued unabated over these past years, but has there been any increase in understanding?
Abstract: In 1967, Douglas was constrained to comment that “Within the past 5 years more studies of the effects of hippocampal lesions on behavior have been published than in all previous years combined. Despite this proliferation of specific knowledge no comparable advance has been made in the general understanding of hippocampal function” (Douglas, 1967, p. 416). The output of research in this area has continued unabated over these past years, but has there been any increase in understanding?
91 citations
TL;DR: Hearing and sight, while playing no part in recognition per se, were important in helping the ewe to locate her lamb and smell depended entirely on smell.
88 citations
TL;DR: A new microtest for cell-mediated immunity is described, which is based on the elaboration of a diffusible factor from sensitized lymphocytes following contact with specific antigen, which may be a new lymphokine, leucocyte adherence inhibition factor (LAIF).
84 citations
TL;DR: A number of differences exists between the compound eyes of larval and adult rock lobsters, Panulirus longipes, including migration of screening pigment on dark-light adaptation, which is accompanied by changes in sensitivity and resolution of the eye.
Abstract: A number of differences exists between the compound eyes of larval and adult rock lobsters, Panulirus longipes. The larval eye more closely resembles the apposition type of compound eye, in which retinula cells and rhabdom lie immediately below the cone cells. The adult eye, on the other hand, is a typical clear-zone photoreceptor in which cones and retinula cell layers are separated by a wide transparent region. The rhabdom of the larval eye, if cut longitudinally, exhibits a “banded” structure over its entire length; in the adult the banded part is confined to the distal end, and the rhabdom is tiered. Both eyes have in common an eighth, distally-located retinula cell, which possesses orthogonally-oriented microvilli, and a peculiar lens-shaped “crystal”, which appears to focus light onto the narrow column of the distal rhabdom. Migration of screening pigment on dark-light adaptation is accompanied by changes in sensitivity and resolution of the eye. Retinula cells belonging to one ommatidium do not arrange into one single bundle of axons, but interweave with axons of four neighbouring facets in an extraordinarily regular fashion.
83 citations
TL;DR: The microcirculation in a transplantable rat fibrosarcoma was investigated and it was concluded that the majority of vascular channels in this neoplasm bear some structural and functional relationship to small venules.
Abstract: The microcirculation in a transplantable rat fibrosarcoma was investigated. The vasculature of the neoplasm consisted of irregular channels lined by plump endothelium which displayed mainly pentalaminar although a few heptalaminar junctions were also found. Few pericytes surround the endothelial layer while the basement-membrane varied in thickness and was often duplicated and triplicated. Challenge with histamine resulted in increased permeability in comparison with normal connective tissues similarly treated. The increased permeability was accompanied by the formation of interendothelial gaps in these irregular vascular channels. Carrageenan induced a leucocytic exudate in the neoplasm which, apart from an increase in the mononuclear concentration 2 wk after injection, varied little from normal connective tissues. It is concluded that the majority of vascular channels in this neoplasm bear some structural and functional relationship to small venules.
73 citations
TL;DR: In this paper, a generalization of Malcev's result is presented, where the automorphism group of the full transformation semigroup F(X) consists of mappings of the form g-1 · g, g ∈ G(X).
Abstract: The full transformation semigroup F(X) is extremely important. As far back as 1952, Malcev (1952) showed that its automorphism group consisted of mappings of the form g-1 · g, g ∈ G(X). The present work is devoted to a generalization of this result.
TL;DR: In this paper, five new cases of inverted urinary papilloma were described and 13 previously reported cases are reviewed, and 18 cases were seen in adult males, with ages ranging from 26 to 79 years (average 57 years).
Abstract: Five new cases of inverted urinary papilloma are described and 13 previously reported cases are reviewed. All 18 examples were seen in adult males, with ages ranging from 26 to 79 years (average 57 years). Ten patients presented with symptoms of bladder outlet obstruction and 8 with haematuria. With one probable exception all of the tumours were solitary. Sixteen were found in the region of the bladder neck and prostatic urethra, and only 2 occurred in other sites. The papillomas were pedunculated or sessile and ranged in size from a few mms to 3 cms in greatest diameter. Most had smooth surfaces in contrast to the usual exophytic papillary urothelial neoplasms. Microscopically they showed a striking resemblance to the inverted papillomas of the nasal cavity and paranasal sinuses. In those examples where the stalk or base of the papilloma was included in the sections, there was no evidence of invasion of the underlying smooth muscle. Fourteen of the patients have been followed for periods ranging from 7 months to 11 years (average 2.5 years) and no recurrences have been documented. Simple local resection, by the transurethral route where possible, appears to be adequate treatment for these distinctive papillomas.
TL;DR: In this paper, the effect of impurities arising as a result of the preparation process, on the pzc and the iep of commercial rutile pigment produced by hydrolysis of the sulfate.
TL;DR: In this article, the percentage of the [ 3 H]-estradiol-17β metabolized was measured by incubating with endometrium obtained at different times during the menstrual cycle.
TL;DR: It is concluded that an ecological, rather than a phylogenetic approach is more useful when comparing levels of metabolism in mammals.
TL;DR: The plasma enzymes alkaline phosphatase, lactate dehydrogenase, aspartate aminotransferase and creatine kinase likewise increased significantly throughout the run, and most constituents showed a tendency to return to normal at 20-30 hours after the run.
TL;DR: New ecological data are given for the nine species of seagrasses of south-western Australia, with special reference to Posidonia australis in Cockburn Sound, a polluted marine embayment.
TL;DR: Results further support the view that the CA1 region mediates two distinct processes in this discrimination, namely a short term memory process in consolidation and a retrieval or comparison process, both appear likely to be related through an attentional mechanism.
TL;DR: The discovery of the remains of house mice, Mus musculus, and black rats, Rattus rattus, in pellets indicates that owls hunt on one island and regurgitate on another (Daphne), and suggests that seeds or fruits in the throat of a victim at the time of a kill may be transported unharmed inside an owl from one island to another.
Abstract: Populations of 4 geospizine finches were studied on Isla Daphne Major in April and December 1973. Finches were captured, banded, measured and released in both months, and censused in December. 1640±711 finches were estimated to be present in December, of which probably more than 1000 belonged to Geospiza fortis. G. fortis were 4 times more numerous than G. scandens. The overal density at this time was 27-54/ha. This is the first quantitative estimate of finch population sizes for a whole island in the Galapagos Archipelago. Some G. fuliginosa and magnirostris immigrated between study periods, but overall density remained nearly constant. There was no evidence of immigration of fortis and scandens. Survival rates of the two common species, fortis and scandens, from April to December were estimated, from banded birds, to be 86.9% and 91.3%. Up to 300 finches (fortis and scandens) disappeared between study periods. The amount of predation by owls (Asio flammeus), estimated from an analysis of 49 pellets, could account for more than 50% of the finch losses, but is likely to be less. The estimated loss due to predation was less than 10% of the populations in April.The discovery of the remains of house mice, Mus musculus, and black rats, Rattus rattus, in pellets indicates that owls hunt on one island (e.g. Santa Cruz or Baltra) and regurgitate on another (Daphne). Fruits of a Euphorb, Chamaesyce amplexicaulis (Hook. f.) Burch, that finches eat were found in two pellets that also contained finch remains. This suggests that seeds or fruits in the throat of a victim at the time of a kill may be transported unharmed inside an owl from one island to another. Indirect support to this suggestion is given by the results of flotation experiments with seeds and fruits of 22 species of plants. Most did not float, and are too heavy to be transported by normal winds. Many do not have hooks or sticky surfaces, and internal transport by birds (including owls) is therefore strongly suggested.
TL;DR: In the present communication, mention will be made of recently published material on the hormonal control of water and electrolyte physiology in reptiles and new information will be presented from unpublished laboratory and field investigations on Australian lizards.
TL;DR: The ability of Merino lambs to find and discriminate their dams when separated by 6–10 m and having the choice of three ewes was examined over the first 4 weeks of life.
TL;DR: Rats with bipolar electrodes chronically implanted in the dentate gyrus of the dorsal hippocampus were trained on a simultaneous visual discrimination task and reversal to support the view that there is functional differentiation within the hippocampus that is related to the anatomical organization of this structure.
TL;DR: Selectivity in transfer of amino acids from xylem to phloem appeared to be an important element in determining the overall balance of nitrogenous solutes in the translocation stream and coupled loading of photosynthate was examined in relation to the seed's requirements for amino acids in protein synthesis.
Abstract: 14C-labelled amino compounds were fed singly to fruiting shoots of white lupin as a 15 min pulse through the transpiration stream. The time course of labelling of phloem was followed over a 6 h period by making successive collections of phloem sap from the cut tips of attached fruits. The distribution of 14C amongst solutes of phloem sap was examined. Seeds harvested at 6 h were analyzed for 14C content and 14C distribution amongst amino acid residues of protein. Certain amino compounds (valine, asparagine, threonine, serine, citrulline, glutamine) were transferred rapidly in unchanged form from xylem to phloem. Each labelled phloem sap intensely, and its 14C was transfrrred to fruit and seed with high efficiency. Other amino compounds (glycine, methionine, aspartic acid, homoserine, glutamic acid and γ-amino butyric acid) passed unchanged to phloem only in small amounts. The bulk of their 14C appeared in phloem sap attached to other substances, especially non-amino compounds and amino acids metabolically related to the one applied. The 14C from each of this second group of amino acids labelled phloem less intensely and was donated to fruit and seed with low efficiency. Selectivity in transfer of amino acids from xylem to phloem appeared to be an important element in determining the overall balance of nitrogenous solutes in the translocation stream. The significance of this and coupled loading of photosynthate was examined in relation to the seed's requirements for amino acids in protein synthesis.
TL;DR: The morphological changes in subcutaneously implanted muscle homografts in mice were studied by light and electron microscopy 1-23 days after transplantation to suggest primitive mononucleated myogenic cells may form within degeneratiang muscle fibres by a process of myonuclear sequestration.
TL;DR: The ototoxicity of chloramphenicol ear drops was studied in guinea-pigs and it was revealed that propylene glycol at the concentration of 10% or more caused irreversible deafness.
Abstract: The ototoxicity of chloramphenicol ear drops was studied in guinea-pigs. The ear drops consisted of chloramphenicol sodium succinate in propylene glycol; hence the ototoxicity of each chemical was also studied. The diluted chemicals were instilled in the middle ear cavity; thus clinical conditions were simulated, and the cochlear microphonic responses from the electrode on the round window of the cochlea were monitored as an indication of the hair cell function. Our experiment revealed that propylene glycol at the concentration of 10% or more caused irreversible deafness. Chloramphenicol sodium succinate in a concentration of 5% or more in Ringer's solution also caused irreversible deafness. It is recommended that propylene glycol should not be used in the ear drops as a solvent of the drug. Chloramphenicol at higher concentrations is not recommended for use in the middle ear cavity.
TL;DR: In this paper, the authors show that the automorphism group of a transformation semigroup is isomorphic to the group gx of all permutations defined on the set of permutations.
Abstract: We let X be an arbitrary non-empty set throughout. Many papers have been written describing the automorphisms of various transformation semigroups defined on X: total (Lyapin (1955), Magill (1967), Malcev (1952), Schreier (1936)), partial (Gluskin (1959), Magill (1967)), partial and 1–1 (Liber (1953)), partial and shifting at most a finite number of elements (Subov (1961a)). In all these cases the automoprhisms are shown to be “inner”, and using the fact this authors deduce that the automorphism group of the given transformation semigroup is isomorphic to the group gx of all permutations defined on X.
TL;DR: Primary plaque forming cell and antibody response to sheep erythrocytes was first enhanced and then depressed by continual cigarette smoke exposure, while the secondary response was unaffected.
Abstract: Mice were exposed to fresh cigarette smoke for 1,17, and 38 weeks. After each period the primary and secondary humoral immune response to intraperitoneal inoculation of sheep erythrocytes was studied. Direct and indirect plaque forming cell responses in the spleen and in a pool of cervical and mediastinal lymph nodes, as well as serum hemolytic and hemagglutinating antibodies were examined. Primary plaque forming cell and antibody response to sheep erythrocytes was first enhanced and then depressed by continual cigarette smoke exposure, while the secondary response was unaffected. Serum antibody response to polyvinylpyrrolidone, an immunogen independent of thymus-derived lymphocytes, was not impaired by 41 weeks of cigarette smoke exposure.
TL;DR: In this article, Ross and Hogben showed that the longer the delay between the two streams, the harder the target is to see in depth, and therefore to identifv.
01 Jan 1975