Showing papers by "University of Sydney published in 1973"

The classification of malignant melanoma and its histologic reporting

Abstract: Apart from the rare malignant melanomas occurring in blue nevi, primary cutaneous malignant melanoma arises in 1 of 3 ways, regardless of the presence or absence of a pre-existing nevus. These three types have been designated: 1. Malignant melanoma, invasive, with adjacent intra-epidermal component of Hutchinson's melanotic freckle type; 2. Malignant melanoma, invasive, with adjacent intra-epidermal component of superficial spreading type; and 3. Malignant melanoma, invasive, without adjacent intra-epidermal component. Occasionally, both clinically and histologically, there may be difficulty in deciding whether a malignant melanoma belongs to category 1 or 2, but, in the majority of cases, these 2 types can be quite readily distinguished. In addition to recording the histogenetic mode of development of a malignant melanoma, a histologic system of reporting is recommended which includes mitotic activity, levels of invasion, and vascular involvement. There are other parameters such as the cell type, pigmentation, lymphocytic infiltrates, evidence of spontaneous regression, associated nevi, and solar changes in the dermis, all of which are of unknown significance. The recording of these features, which are clearly of interest for research purposes, is left to individual discretion. It is emphasized that all the usual macroscopic descriptions and measurements should continue to be recorded.

The phospholipid-bound fatty acids and aldehydes of mammalian spermatozoa

Abstract: 1. 1. The phospholipid-bound fatty acids of ram, bull, boar, rabbit and human spermatozoa contained high levels of polyunsaturated fatty acids. Values ranged from 70 per cent by weight of the total fatty acid fraction in the boar to approximately 40 per cent in both human and rabbit. 2. 2. Docosahexaenoic acid (22:6) was quantitatively the most important fatty acid found in all species except the rabbit. 3. 3. The major saturated fatty acid found in mammalian spermatozoa was palmitic acid. 4. 4. The predominant fatty aldehyde was palmitaldehyde (16:0) and values ranged from 91·2 per cent in ram to 51·1 per cent in human spermatozoa.

Significance of path coefficient analysis in determining the nature of character association

Abstract: Interrelationships among production characters were determined both by simple correlation and path coefficient analyses, using ecogeographically diverse spring wheat genotypes. Simple correlation analysis indicated that kernel weight correlated positively with plant height and negatively with heading time. Also spike number and kernel weight showed highly positive and heading time highly negative correlations with grain yield. Path coefficient analysis was useful in that it revealed the true nature of cause-and-effect relationships of heading time, plant height, spike number and kernel weight with grain yield. Wherever feasible, path coefficient analysis should be conducted in addition to simple correlation analysis.

Turbulent diffusion flames

Abstract: Experimental results are presented for turbulent diffusion flames of a round jet of hydrogen in a co-flowing stream of air. The aim of the work is to provide comprehensive data which will assist in refining the newer and more-powerful theories coming into use. The jet diameter was 7.62 mm and the tunnel cross section large enough so that the flames were essentially unconfined and near to zero pressure gradient. Buoyancy effects were also negligible. Measurements were made at jet to external stream-velocity ratios of 2, 5, 8, and 10 to 1. Measurements made include jet exit-plane velocity and turbulence profiles, and concentration, temperature, and momentum flux within the flame. Some results for turbulence levels and nitric oxide concentrations are also presented. The general level of accuracy of the experiments is believed to be good. However, it was found that derivation of velocity is extremely sensitive to small errors in concentration measurements in the outer part of the flow, where the density gradients and fluctuations are steepest. The results are discussed in the light of the theories of Libby and Spalding. It is considered that such theories should use the time-mean density, which takes into account the fluctuating composition at a point in the flow, and that current models of turbulence may need modification. Peak nitric oxide concentrations are found to lie considerably on the rich side of the stoichiometriccontour. Nitric oxide production rates on the centerline have been deduced from the experimental data and show a peak at a mean composition having 60 per cent of theoretical air. No reasonable theoretical explantation has been found for these results.

Production by Stimulated Macrophages of Factors depressing Lymphocyte Transformation

Abstract: MACROPHAGES can inhibit the responses of lymphocytes to a variety of stimuli. The presence of excessive numbers of normal macrophages led to inhibition of antibody formation by cultured mouse lymphoid cells1–3. Normal rat spleen cell suspensions responded better to non-specific stimulation by Gram-negative bacterial lipopolysaccharide (endotoxin) after being freed of macrophages, but the response was reduced again by the addition of macrophages4. Spleen cells from mice injected with Coryne-bacterium parvum5,6 or subjected to a graft-versus-host (GvH) reaction6,7 showed decreased antibody formation7 and decreased responsiveness to phytohaemagglutinin (PHA) or allogeneic lymphocytes5 when cultured in vitro. Such mice possess activated macrophages8,9. Their spleen cell responses were restored, at least in part, by removal of macrophages6,7. Attempts to demonstrate the production of soluble inhibitors by macrophages in vitro have generally been unsuccessful6,7,10. Mouse serum can inhibit primary antibody formation11–14 and mitogen-induced transformation of T lymphocytes and B lymphocytes in cultures of mouse spleen cells ; we have suggested (ref. 15 ; D. S. N. and C. N. Shneider, unpublished) that the factor responsible for the latter effect may be produced by macrophages. Here I present evidence that mouse peritoneal macrophages activated in vivo produce a potent inhibitor of lymphocyte transformation when cultured in vitro.

An experimental investigation of an axisymmetric jet in a co-flowing air stream

Abstract: An experimental investigation of the flow development of an axisymmetric jet exhausting into a moving air stream is made for two values of the ratio of jet velocity to external air velocity. The u-component turbulence intensity and Reynolds shear stress measurements together with the dissipation length scales inferred from measured u-component spectra suggest that the turbulence similarity assumptions are incorrect for the present flow situation. A discussion of the turbulence structure of the flow indicates that self-preservation does not apply for this situation and that the flow far downstream depends strongly on the complete past history.

National Income, Expenditure and Output of the United Kingdom, 1855–1965 . By C. H. Feinstein. Cambridge, Cambridge University Press, 1972. Pp. ix + 244 and 141 pages of Tables. £10.00.

Abstract: One can only admire C. H. Feinstein's ability and energy. Over the last decade or so he has provided an enormous amount of historical statistical data for the British economy. The present volume provides a fitting culmination of many years of laborious work, and it will no doubt serve as a quarry for historians and economists for a long time to come. It ensures too that the name of Feinstein will secure a firm placing in the annals of statistical inquiry. No doubt Dr. Feinstein would be the first to admit that this is not an easy book to read, for obvious reasons. It comprises sixty-five master tables covering national income and its main sub-aggregates profits, capital formation, indices of production, population and labor force, prices, wages and balance of payments, as well as many summary tables in the text. In other words, it includes most of the main macroeconomic data necessary for a study of the U.K. economy since the mid-nineteenth century, which is promised in due course. The first part of the volume is devoted to a detailed explanation of the sources and methods used in compiling the estimates. Despite its length (over 200 pages), a number of doubts and queries remain, and since it would be impossible in a short review to go through the volume in detail, I shall confine my attention to raising one or two points which came to mind when reading the volume. Users of the data should be aware of the fact that some of the estimates are subject to considerable margins of error, though Dr. Feinstein frequently expresses a quiet degree of confidence in many of his calculations. Not surprisingly, the farther one goes back in time, and for those periods which include major wars, the less reliable are the estimates. Some of the sector estimates, for example those for the output of road haulage and certain services, are not based on very firm foundations. Moreover, it is essential that whatever section of the data the reader wishes to utilize he first reads carefully the relevant explanatory notes on compilation. Even then some doubts will remain. For instance, on page 209 it is stated that twenty-three indicators were used for compiling the output of transport and communication, forty-nine for the distributive trades, and twenty-nine for professional and miscellaneous services for the inter-war period, but we are given very little information as to exactly what is included. Some of the sector estimates do not give grounds for great confidence. A difficult one proved to be road haulage for the years 1920-1938, and here resort was had to a weighted index of goods vehicles in use. This is obviously not particularly satisfactory, given the fact that the licensing system of 1933 checked the growth

Analysis of piles in soil undergoing lateral movement

Abstract: An analysis is described for the behavior of a pile in a soil undergoing lateral movements due to some external cause such as an embankment. Some of the factors affecting the development of pile displacements, moments, and reactions are examined, and it is found that the most important factors are the relative flexibility of the pile, the boundary conditions at the top and the tip, and the distribution of soil movement with depth along the pile. Limited comparisons between theoretical and observed pile behavior suggest that the theoretical approach could be applied with some degree of confidence to field problems.

The effect of cannabinoids on intestinal motility and their antinociceptive effect in mice

Abstract: 1. After oral administration to mice, pethidine, Delta(8)-tetrahydrocannabinol (THC), Delta(9)-THC, a cannabis extract and cannabinol had a dose-dependent antinociceptive effect when measured by the hot-plate method. Cannabidiol was inactive at 30 mg/kg. Delta(8)-THC, Delta(9)-THC and pethidine did not differ significantly in potency, but Delta(9)-THC was 6.5 times more active than cannabinol.2. After oral administration, three different cannabis extracts, Delta(8)-THC, Delta(9)-THC and morphine produced dose-dependent depressions of the passage of a charcoal meal in mice. Delta(8)-THC and Delta(9)-THC were equipotent and were about five times less potent than morphine. Cannabidiol was inactive up to 30 mg/kg. The effect of the three cannabis extracts on intestinal motility could be accounted for by their Delta(9)-THC content.3. The antinociceptive effect of pethidine and the effect of morphine on intestinal motility were antagonized by nalorphine whilst the effects of the cannabis extracts and the pure cannabinoids were not.4. From these results it is concluded that although cannabis and the narcotics share several common pharmacological properties, the mode of action of each is pharmacologically distinct.

Jaw movements in young adult men during chewing.

Abstract: Jaw movements of a selected group of subjects were studied by clinical observation, examination of wax occlusal records and mounted casts, photoelectric mandibulography, and oscilloscopic tracings. Subjects were found to have substantially consistent and reproducible patterns of jaw movement during empty and functional chewing exercises. However, the individual patterns could not be predicted from analysis of occlusal status. Mean values of (1) the chewing cycle time, (2) the pause at centric occlusion, (3) maximum opening, (4) maximum movement to the right and left of the midline, and (5) maximum jaw point velocity while opening, closing, and moving to the right and left were obtained for 22 subjects chewing a single peanut on the right and the left sides. Great diversity in chewing patterns was observed, but in general, individual subjects exhibited specific and repetitive patterns. All subjects exhibited a pause in centric occlusion at the end of a closing masticatory stroke. A substantially constant jaw point velocity was observed for most of a chewing cycle when the open-close, close-open, left-right, and right-left components of jaw movements were analyzed separately.

Milk Carbohydrates of the Echidna and the Platypus

Abstract: The principal neutral carbohydrate of three samples of echidna milk was identified as a trisaccharide, fucosyllactose. That of a sample of platypus milk was a tetrasaccharide, difucosyllactose. Free lactose was found in small amounts only. The milk carbohydrate of monotremes is distinguished from that of both marsupials and placental mammals by its high fucose content.

Nasopharyngeal reflexes: integrative analysis of evoked respiratory and cardiovascular effects.

Abstract: NASOPHARYNGEAL REFLEXES: INTEGRATIVE ANALYSIS OF EVOKED RESPIRATORY AND CARDIOVASCULAR EFFECTS

Angular quadrature perturbations in radiative transfer theory

Abstract: A new numerical method is presented for solving the general equation of radiative transfer. The approximation, which replaces the integral term over angle in the transfer equation by a quadrature sum, is studied; an estimate of the error involved is obtained and this error, which may be thought of as a further source or sink of photons (depending upon the sign), can then be used to evaluate a corection to the radiation field originally determined. This process may then be continued as a perturbation series. The method is found to give a final solution, when starting from the Eddington approximation, at least as accurate as that obtained using variable Eddington factors. Furthermore, the technique involves very little extra computing over that required using the Eddington approximation, and may be trivially generalized to any radiative transfer problem. It can also be used in conjunction with any of the existing methods for solving the equation of transfer. Examples are given in the context of spectral line formation in slab geometry.

The pharmacology of marihuana

Abstract: DISCUSSION A wide range of adverse effects associated with the use of neuroleptics has been described (Sargant and Slater, 1963). New reports of adverse effects continue to appear, with neurological effects predominant in the literature (Crane, 1971). The case reported is believed to belong to a category which has been recently recognized (Behrman, 1972). This category described progressive mutism, increasing inertia and decreasing mental alertness, lapsing slowly or rapidly into fully developed \"akinetic mutism\". The onset of symptoms began up to 18 months after the commencement of treatment with neuroleptics. In half the patients mutism gradually remitted after the cessation of medication, but in the rest progress was much slower and in one recovery was incomplete. Half the patients also displayed the more well-known neurological side effects of neuroleptics and 2 had persistent stereotyped movements. It was suggested that akinesia may be caused by deafferentiation of the cerebrum from the activating influences of the ascending brain-stem reticular formation as a result of dopamine blocking action.

Steric stabilization II

Abstract: A theory of steric stabilization is developed that is essentially an extension ofFischer's solvency theory. It treats both interpenetration and compression using a latice approach. This permits the introduction of segment density distribution functions. One virtue of the new theory is that it is in good qualitative agreement with the results of experiment. Some limitations of the theory are also noted.

An ultrastructural comparison of peripheral nerve allografts and autografts.

Abstract: There is a marked difference in the cellular response of the host to peripheral nerve allografts and autografts. The response elicited by allografts is characterised by invasion of tissue with lymphocytes, plasma cells and activated macrophages. These cells disrupt the nerve architecture, and cause rupture and consequent compression of the neurolemmal tubes which are the essential conduit element of a nerve graft.

The comprehensive factorization of a functor

Abstract: In this article we show that every functor has a factorization into an initial functor followed by a discrete O-fibration and that this factorization is functorial. Size considerations will be ignored but may be easily filled in; we assume the existence of a category of sets large enough to dwarf any given finite number of categories. There is an analogy between the category Set of sets and the category Cat of categories which is partly explained by the observation that each is a category of types for a suitable hyperdoctrine. A hyperdoctrine (Lawvere [4]) consists of a category Tof types and a functor P: T -• Cat satisfying conditions. The comprehension schema (also see [4]) is expressed by a pair of adjoint functors

A comparison of the effects of irradiation and immunosuppressive agents on regeneration through peripheral nerve allografts: an ultrastructural study.

Abstract: Peripheral nerve regeneration through irradiated allografts, simple allografts and allografts with immunosuppression of host was compared in rats. Regeneration through irradiated nerve allografts compared unfavourably to that through autografts or through allografts in animals treated with immunosuppressive agents. The regenerative process in irradiated grafts was prolonged because of the slow removal of myelin and axoplasm from the neurolemmal tubes, infiltration of the graft with inflammatory cells and a heavy deposition of collagen. Consequently few fibres of small diameter were able to traverse a 4 cm irradiated graft in the rat. Regeneration was more successful through simple allografts in animals treated with immunosuppressive agents. Immunosuppressive agents aid regeneration by reducing the immune response which causes destruction of the nerve architecture and collagen deposition.

A study of occupational stress and health.

Abstract: Because of claims by telegraphists' unions in a large Australian communications organization that their members suffered various forms of ill-health as a result of stresses imposed by their work, sickness absence, medical and environmental studies of the occupation were undertaken. Records of absence over a period of 2.5 years in all telegraphists in the organization, and in random samples of clerks and mechanics in all State capitals and of mail sorters in Sydney in the same organization were analysed; 516 telegraphists in Sydney, Brisbane and Melbourne (a 93% response) and, for comparison with Sydney telegraphists, 155 Sydney mail sorters (a 79% response) were interviewed and examined medically; and detailed ergonomic and occupational hygiene investigations were made into the work environment. There were gross occupational and geographic differences in absence experience, which were particularly marked in absence attributed to neurosis. In every capital the proportion of neurotic absentees was greater i...

On the accuracy of some mark-recapture estimators

Abstract: The behaviour of the mark-recapture estimators of Petersen, Bailey (triple catch) and Jolly and Seber are examined theoretically and empirically by means of simulation techniques. The correlation between the parameter [Formula: see text] and its associated variance is shown to be significant for all the estimators. This correlation makes the estimated variance an insensitive measure of the accuracy of the estimate except at very high sampling intensities. Such sampling intensities are rarely achieved in experimental work and so the method of mark-recapture must be considered of very limited use. At the sampling intensities necessary to give a coefficient of variation of less than 0.05 it does not seem likely that the correlation between [Formula: see text] and its variance will produce serious underestimation but the minimum confidence limits [Formula: see text] are recommended.