Showing papers by "Monash University published in 1974"
394 citations
TL;DR: The mathematical theory of measurement is used to construct a framework for the evaluation of information retrieval strategies based on precision and recall and a number of other measures are shown to be special cases of it.
Abstract: The mathematical theory of measurement is used to construct a framework for the evaluation of information retrieval strategies. The model arrived at is based on precision and recall. After a detailed examination of the kind of conditions the model can be expected to satisfy a plausible measure of effectiveness is derived. Finally, a number of other measures are shown to be special cases of it.
243 citations
TL;DR: In mice with inhibited acid secretion, parietal cells showed an accumulation of cytoplasmic tubules and vesicles and reduction in the numbers of microvilli, andMeasurements of acid secretion in control animals and in animals treated with acid secretagogues indicated hydrogen ion secretion contemporaneous with depletion of the cy toplasmo-tubulovesicular membranes and with increase of the microVilli.
Abstract: Gastric parietal cells in mice present a spectrum of microscopic appearances due mainly to variations in the abundance of the tubular and vesicular component of the cytoplasm and in the size and number of microvilli lining the intracellular canaliculi. Differences in the range of forms among parietal cells of fasting versus fed mice were not especially striking, but cells with very numerous tubules and vesicles were more common after fasting. However, in mice treated with drugs or hormones that induce acid secretion, parietal cells were more uniform in appearance. There was a marked reduction of these cytoplasmic membranes and a concomitant increase in both the number and size of microvilli. Measurements of acid secretion in control animals and in animals treated with acid secretagogues indicated hydrogen ion secretion contemporaneous with depletion of the cytoplasmic tubulovesicular membranes and with increase of the microvilli. In mice with inhibited acid secretion, parietal cells showed an accumulation of cytoplasmic tubules and vesicles and reduction in the numbers of microvilli. Stereological methods were used to quantitate 10 different parietal cell compartments. Tracer studies with lanthanum did not reveal continuity between the tubules and the plasma membrane. However, there were regions of close apposition between the tubulovesicular membranes and the cell membrane of the canaliculus, and instances where cytoplasmic tubules extended from the cell into the core of enlarged microvilli.
167 citations
TL;DR: Three models, developed by Karlin, McGregor and Ewens to describe evolving populations of selectively neutral genotypes, are shown to lead to various versions of Fisher's logarithmic series distribution for species abundance.
129 citations
TL;DR: It is concluded that the symplastic pathway is the only possible one for assimilate traffic across the mestome sheath in wheat, and that diffusion down a gradient of sugar concentration from the chloroplasts to the sheath acts as the driving force.
Abstract: The distribution of pit fields and plasmodesmata in the mestome-sheath cells of a wheat leaf has been determined by study of sections and partial macerates. Each bundle is approximately symmetrical about the sagittal plane and most plasmodesmata occur in the mestome sheath where its cells abut the metaphloem. Plasmodesmata are absent adjacent to xylem vessels, and the frequency of plasmodesmata declines sharply in cells that lie close to the sagittal plane. Calculations show that 1 cm2 of leaf lamina has approximately 2x108 plasmodesmatal connections to the phloem of the longitudinal veins, and that 85% of these connections are to the late-maturing intermediate bundles that do not complete their differentiation until leaf growth is nearly finished. The phloem area of inner tangential wall of the mestome sheath amounts to 0.26 cm2 per cm2 of leaf area and plasmodesmata occupy 1.5% of this area.
102 citations
TL;DR: Thalamic lesions involving the LGN in older kittens caused fiber degeneration in the other visual areas, and this was first seen in the lateral suprasylvian gyrus (SSG) at six days, in area 19 at 14 days, and in area 18 at 21 days.
Abstract: Lesions were made in the visual system in a series of kittens, and fiber degeneration stained by the Eager or Fink-Heimer methods. Stereotaxic lesions made in the lateral geniculate nucleus (LGN) in one day old kittens led to the appearance of finely dotted fiber degenerationn in area 17 (concentrated in layer IV) two days later. Thalamic lesions involving the LGN in older kittens caused fiber degeneration in the other visual areas. This was first seen in the lateral suprasylvian gyrus (SSG) at six days, in area 19 at 14 days, and in area 18 at 21 days.
Lesions of visual cortex affecting areas 17 and 18 caused degeneration of descending connections to the LGN, lateralis posterior and superior colliculus when made in kittens one day old. However, ipsilateral cortical connections to area 19 were not seen until the kittens were 19 days old at operation, and connections to the suprasylvian gyrus appeared at 21 days. Contralateral cortical connections carried by the corpus callosum were not seen until the kittens were 26 days old at operation, and a distribution of degeneration comparable with that seen in adults was present at 40 days.
This time sequence of development is discussed in relation to what is known about the time of development of functioning in the cat's visual system.
97 citations
TL;DR: In this article, a simple nonlinear model is described which has several advantages over the traditional unit hydrograph technique, such as it allows catchment and rainfall variability to be modeled and it easily accommodates the case where gaging stations are remote from proposed dam sites.
Abstract: A simple nonlinear model is described which has several advantages over the traditional unit hydrograph technique The catchment is divided into several subcatchments, the storage characteristics of which are represented by conceptual stores of S = kQ m The value of the exponent, m , is found to be reasonably constant in practice The model was applied to two catchments in Victoria, Australia, and found to perform well The chief advantages of such a model are that it allows catchment and rainfall variability to be modeled and that it easily accommodates the case where gaging stations are remote from proposed dam sites
87 citations
TL;DR: It is evident that evaporative cooling may be employed successfully throughout the hottest hours of the day in gregarious larvae of Perga dorsalis.
71 citations
TL;DR: A brief survey in Southern Africa revealed 11 grass species and a number of sedges with foliage that recovers from air-drying and desiccation tolerance limits were extremely low being equivalent to approximately 0-5 % relative humidity.
Abstract: A brief survey in Southern Africa revealed 11 grass species and a number of sedges with foliage that recovers from air-drying (equivalent to equilibrium with air at 20-40 % relative humidity at 28° C.). The desiccation tolerance limits were extremely low being equivalent to approximately 0-5 % relative humidity. Some species may have a potential use in agriculture.
68 citations
TL;DR: A random controlled trial was performed to compare the effects of the dorsal and left‐tilt delivery positions upon fetal acid‐base status, and the dorsal position was associated with a time‐related decrease in fetal pH, whereas the left tilt position was not.
65 citations
TL;DR: The familiar species-area equation S=cAz may not account for as much of the variation in the numbers of species on islands as it has been held to.
Abstract: The familiar species-area equation S=cAz may not account for as much of the variation in the numbers of species on islands as it has been held to. The undue emphasis on area as a factor probably results from early workers not considering as many factors as possible in their regression analyses.
In the case of 19 remote islands in the Southern Hemisphere, island area and elevation, latitude, mean temperature of coldest month and distance of island from mainland, nearest land and nearest land to west were used to consider variation in number of plant species with the technique of multiple regression. A nonlinear model explained 83% of the variation, with temperature and area accounting for 71% of the variation in number of plant species.
The above factors with number of plant species were then used to consider variation in number of insect species on the islands. The linear model was superior, accounting for 91% of the variation. Number of plant species accounted for 73% of the variation in number of insect species.
Variation in numbers of passerine bird species and total land bird avifauna was considered using all of the above nine factors. The linear model was superior in both cases. Number of plant species accounts for 60% and 71% of the variation respectively.
Various suggestions are made to account for the unexpected result of number of insect species making little contribution to the last two regressions.
TL;DR: The current state-of-knowledge with respect to methods for the regulation of fertility in the male is presented and areas where future studies may be profitably encouraged are indicated.
TL;DR: Compatibility was shown between the group 1 R factor and a group 2 R factor, providing additional evidence for significant genetic differences.
Abstract: R factors have been demonstrated in multiply drug resistant strains of enterobacteria and Pseudomonas aeruginosa in a Birmingham hospital (Lowbury et al. 1969; Ingram, Richmond & Sykes, 1973). A comparative genetic analysis of these R factors has been initiated on the basis of a variety of phenotypic characteristics. This paper describes the properties of R factors derived from strains which could transfer multiple drug resistance to the recipient species P. aeruginosa, Escherichia coli, Shigella flexneri and Salmonella typhimurium . Two types of R factor could be recognized phenotypically. The single group 1 R factor, R18–1 which is probably the same as RPl-1 (Ingram et al. 1972) was different to the group 2 R factors in many respects, including host range, R factor-specific phage plating, cellular location, drug resistance pattern, and stability. The group 2 R factors were found to be very similar to RPl (Grinsted et al. 1972) and R1822 (Olsen & Shipley, 1973) with respect to their wide host range, plating of a sex specific phage, extrachromosomal location, and drug resistance pattern. Compatibility was shown between the group 1 R factor and a group 2 R factor, providing additional evidence for significant genetic differences.
TL;DR: Experiments were performed with preparations obtained by medial transection of the rat vas deferens providing urethral and testicular segments to determine whether the smooth muscle of this organ responds uniformly to field excitation of sympathetic nerve terminals and to sympathomimetic amines.
Abstract: SUMMARY 1. Experiments were performed with preparations obtained by medial transection of the rat vas deferens providing urethral and testicular segments, to determine whether the smooth muscle of this organ responds uniformly along its length to field excitation of sympathetic nerve terminals and to sympathomimetic amines.
2. Both preparations responded to pulses applied at 0.1 Hz with twitches which were blocked by guanethidine (1–10 μM) indicating that sympathetic nerve terminals were being stimulated. Xylazine (0.01–1 μM) also blocked the twitches.
3. In response to stimulation at 0.1 Hz the twitches of the urethral segment were larger but briefer than those of the testicular segment. However, the increase in tension with increase in stimulation frequency over the range 0.01–10 Hz was greater in the testicular than in the urethral segment. After a train of pulses at 1 Hz or above, the first few twitches of the testicular segment evoked by pulses applied at 0.1 Hz were facilitated, whereas twitches of the urethral segment were inhibited.
4. Noradrenaline (1–100 μM) and tyramine (1–100 μM) regularly enhanced twitches in response to stimulation at 0.1 Hz in the testicular segment but often reduced those in the urethral segment. Contractions in response to these amines occurred more regularly and were stronger in the testicular than in the urethral segment. The α-adrenoreceptor antagonists phenoxybenzamine (0.01 μM), phentolamine (10 μM) and thymoxamine (10 μM) blocked contractions and blocked or reversed the twitch enhancement produced by noradrenaline and tyramine. These observations indicate that the density of excitatory α-adrenoreceptors is greater at the testicular end of the tissue.
6. Twitch inhibition evoked by noradrenaline or by tyramine in urethral segments was resistant to blockade by phenoxybenzamine (0.01 μM), phentolamine 10 μM), thymoxamine (10μM) and propranolol (10 μM).
7. A histological comparison of the two ends of the vas deferens indicated that at the urethral end there was more circularly arranged muscle and that this interrupted bundles of longitudinally arranged muscle. The testicular end was thinner but had the higher proportion of longitudinally arranged fibres.
8. The differences between the two ends of the vas deferens in the arrangement of muscle layers and in the response to sympathetic nerve stimulation and to drugs may be of physiological significance in relation to the transport of sperm from the epididymis to the urethra.
TL;DR: A selection procedure is described which was used to isolate mutants of Pseudomonas putida strain U in the following enzymes of the meta-fission pathway of phenol and cresols: hydrolase, tautomerase, and decarboxylase.
Abstract: A selection procedure is described which was used to isolate mutants of Pseudomonas putida strain U in the following enzymes of the meta-fission pathway of phenol and cresols: hydrolase, tautomerase, and decarboxylase Strains deficient in the hydrolase are unable to use either o- or m-cresol as a sole carbon source and were shown to accumulate 2-hydroxy-6-keto-2,4-heptadienoate when incubated in the presence of o- or m-cresol When 2-hydroxymuconic semialdehyde (plus nicotinamide adenine dinucleotide, oxidized form) was metabolized by phenol-induced extracts of tautomerase-deficient strains, the enol tautomer of 4-oxalocrotonate accumulated and was then converted slowly to the keto tautomer by a nonenzymatic reaction Phenol-induced extracts of decarboxylase-deficient strains accumulated the keto tautomer of 4-oxalocrotonate from 2-hydroxymuconic semialdehyde (plus nicotinamide adenine dinucleotide, oxidized form) Strains with an inactive decarboxylase are unable to completely metabolize either phenol or p-cresol Tautomerase-defective strains are unable to grow with p-cresol as the sole carbon source and grow only very slowly on phenol
TL;DR: The abnormal flow patterns of lipids in sciatic nerves of dystrophic mice are considered in relation to the abnormal pattern of axoplasmic protein flow in these animals.
01 Jan 1974
TL;DR: The rich inflow of afferent signals from the extensive array of receptors within and in relation to these tissues must be expected to have widespread and far-reaching effects at many levels of central nervous activity, of particular relevance to the control and guidance of the muscles themselves in their maintenance of posture and execution of movement.
Abstract: Skeletal muscle and its tendinous attachments constitute a major fraction — probably approaching half — of the total body mass. The rich inflow of afferent signals from the extensive array of receptors within and in relation to these tissues must be expected to have widespread and far-reaching effects at many levels of central nervous activity, of particular relevance to the control and guidance of the muscles themselves in their maintenance of posture and execution of movement. Indeed, long before the incontrovertible demonstration of the existence of this sensory equipment (Sherrington, 1894), the general notion of muscle as a source of afferent signals had been entertained. According to Liddell (1960), Charles Bell first formulated the idea of such sensory feedback, writing in 1826: ‘‘Between the brain and the muscle there is a circle of nerves; one nerve conveys the influence of the brain to the muscle, another gives the sense of the condition of the muscle to the brain”. Several generations later this notion was rediscovered and made respectable by mathematics and the coining of a new word, cybernetics.
TL;DR: Sieve elements with thick, lignified walls are identified in the longitudinal bundles of the wheat leaf and appear to be functional and present in several festucoid grasses but seem to be absent from the panicoid grasses examined.
Abstract: Sieve elements with thick, lignified walls are identified in the longitudinal bundles of the wheat leaf and appear to be functional. They are also present in several festucoid grasses but appear to be absent from the panicoid grasses examined.
TL;DR: The results show that large doses of the active peptide HGH 1-15 do not increase the degree of lowering of blood glucose, but prolong the effect of the peptide and depress plasma immunoreac-tive insulin (IRI) in rabbits.
Abstract: Various synthetic fragments of the amino terminal sequence of human growth hormone (HGH) have been studied with respect to their in vitro action on glucose uptake and in vivo insulin potentiating effects. The results show that the biologic activities so far investigated are confined to sequences containing the octapeptide, Leu-Ser-Arg- Leu-Phe-Asp- Asn-Ala.
There is also a correlation between the in vitro reversal of somantin induced inhibition of glyceraldehyde-3-phosphate dehy-drogenase by the active peptides and their insulin potentiating effect in vivo. The GAPD system provides a convenient and rapid means for monitoring such peptides, but its physiologic significance is at present in doubt.
Large doses (10 mg./kg. body weight) of the active peptide HGH 1-15 do not increase the degree of lowering of blood glucose, but prolong the effect of the peptide and depress plasma immunoreac-tive insulin (IRI) in rabbits.
The mechanism of action of the active sequence has not been established at present, and the physiological significance is not yet known.
TL;DR: It is suggested that a more general model than the Borel-Tanner model is the two-parameter Miller distribution of bunch sizes which can be fitted to a wide range of traffic conditions.
TL;DR: In this paper, the behavior of a particle in simple nonuniform fluid flows is discussed and it is found that a particle may follow an approximately closed trajectory in an axisymmetric flow about a horizontal axis.
Abstract: Equations of motion, valid for a water droplet or a dust particle less than about 50Μm in radius moving through the air, are derived. Thus, the behaviour of a particle in some simple nonuniform fluid flows is discussed. In particular, it is found that a particle may follow an approximately closed trajectory in an axisymmetric flow about a horizontal axis. Thus, it is argued that turbulence should cause particles to fall at a much slower rate than their terminal velocity, even in the absence of a mean updraft.
TL;DR: Investigation of a group of patients with classical von Willebrand's disease by the additional techniques of ristocetin induced platelet aggregation and quantitative immunoelectrophoresis for factor VIII related antigen indicate that there is considerable heterogeneity in this condition.
TL;DR: In this article, the structure of (PCH 3 ) 6 W(CO) 4 was determined by a single crystal X-ray diffraction study using Patterson and Fourier methods and refined by least-squares techniques to an R of 0.09 for 1091 independent reflections.
TL;DR: In this paper, the authors considered a population process where individuals reproduce according to an age-dependent branching process and immigrants enter the population at the event epochs of an ergodic point process.
TL;DR: In this article, the authors argue that research on teacher effects should consider pupil variables; teacher behaviours and pupil outcomes may enter into lawful relationships with one another, the nature of the relationship being different for different kinds of pupils Data from a study of pupils' attitudes to physics are used to support this position
Abstract: Summary Process-product studies of the effects of teacher behaviours upon pupil outcomes often employ class mean scores as measures of the outcome variable Assuming that all the measures used are reliable, a zero correlation between the teacher measure and the pupil outcome implies that the teacher behaviour being studied does not affect pupils in any lawful way However, such a conclusion may be faulty This article argues that research on teacher effects should consider pupil variables; teacher behaviours and pupil outcomes may enter into lawful relationships with one another, the nature of the relationship being different for different kinds of pupils Data from a study of pupils' attitudes to physics are used to support this position
TL;DR: In this article, the authors suggest an evolutionary typology of languages (early modern, modern, contemporary, etc.) and specify the position of present day Japanese on this evolutionary scale.
Abstract: The aim of this paper is twofold. First, the author wishes to suggest an evolutionary typology of languages (early modern, modern, contemporary, etc.) and to specify the position of present day Japanese on this evolutionary scale. Secondly, it suggests a way to integrate the concept of linguistic modernization with a theory of language problems, and shows that for modernization at least two types of processes, macro-modernization and micro-modernization, must be distinguished. The former concerns such tasks as the establishment of a modern national language and as far as Japan is concerned this process has been completed. The latter process concerns problems such as the individual's use of language. It still awaits its completion. (Sociolinguistic typology, language evolution, linguistic modernization, Japan.)