Showing papers by "RMIT University published in 1981"
TL;DR: In this paper, high resolution Rutherford backscattering and channeling was employed to measure the substitutional solubility of Ar, As, In, Sb and Pb, implanted into (100) and (111) silicon.
49 citations
TL;DR: In this article, a simple circuit model for the transition from a Iossy microstrip to coaxial line has been developed on an experimental basis, which can be used to predict accurately the insertion loss and insertion phase over a wide frequency range.
Abstract: A simple circuit model for the transition from a Iossy microstrip to coaxial line has been developed on an experimental basis. The proposed model can be used to predict accurately the insertion loss and insertion phase over a wide frequency range. Since explicit formulas for the model element values are given, these elements, representing the parasitic of the transitions, can be taken into account very easify when the microstrip is used as a test fixture for measuring the parameters of solid-state devices. The practical use of the model has been examined for several Z/sub 0/=50-omega lines on both Epsilam-10 and 99-percent alumina substrates with standard SMA coaxial connectors.
31 citations
TL;DR: The findings now raise the interesting possibility that the preventive effects on cancers with exogenous retinoids may be mediated through the cellular binding protein, which is similar in many ways to CRBP isolated from mammalian tissues.
Abstract: Vitamin A (retinol) is essential for the support of growth in higher animals and for the maintenance of normal cell differentiation in epithelial tissue.' In addition, since the observation of Fujimakiz in 1926, it has become well known that there is a keen relationship between vitamin A and carcinogenesis; i.e., vitamin A and its analogs (collectively termed retinoids) are useful for prevention of the development of various cancers, particularly bladder and breast cancer, in experimental animals.3\" Recently, it has been also established that many tissues contain two distinct binding proteins for retinol and its acid derivative (retinoic acid) in the cytosol: cellular retinol-binding protein (CRBP)S and cellular retinoic acid-binding protein (CRABP).6,7 Moreover, it has been reported that both CRBP8.9 and CRABP,lO*ll extensively purified to a homogeneous component, have similar molecular weights (about 14,600), whereas they are distinguished by a strict binding specificity either for retinol or for retinoic acid, respectively. In addition, CRABP has been shown to be present in several human tumors, including breast and lung cancer,lZ and hepatocellular car~inoma13'~~ and in experimental tumors.15\"6 These findings now raise the interesting possibility that the preventive effects on cancers with exogenous retinoids may be mediated through the cellular binding protein.17 During the course of comparative studies on retinol transport in plasma, Shidoji and Muto18 have recently reported that retinol-binding protein (RBP), purified from the fish plasma to a homogeneous component, is distinctly different from that in other classes of the vertebrates higher than postmetamorphic Amphibia: i.e., it is a smaller protein with a molecular weight of 16,000, has a greater mobility on gel electrophoresis (in the prealbumin region, due to a lower isoelectric point of 4.3), and most importantly, has no binding affinity for the other plasma protein, prealbumin (PA) (and hence circulates in plasma exclusively as a monomeric form). Thus, the piscine RBP apparently lacks a binding site for PA, and seems to be similar in many ways to CRBP isolated from mammalian tissues. These similarities prompted us to investigate further the specific binding proteins for retinoids in the fish-eye cytosol. The studies showed that fish-eye
29 citations
TL;DR: Studies were carried out on two sugar estates in the humid coastal forest region of northeastern Brazil, a highly endemic area of schistosomiasis mansoni, finding clear-cut results that reduced productivity among the hepatosplenic subjects compared to intestinal subjects was 35.1%.
Abstract: Studies were carried out on two sugar estates in the humid coastal forest region of northeastern Brazil, a highly endemic area of schistosomiasis mansoni. Results obtained in a retrospective study were not conclusive, but clear-cut results emerged from a prospective study. The latter was conducted on a sugar estate (Catende) where the severe hepatosplenic clinical form of the disease is seen in 4% of the field-working population. Comparison was made between two groups of paired subjects: one composed of workers with the hepatosplenic form of the disease and the other composed of workers with the intestinal form. Reduction of productivity among the hepatosplenic subjects compared to intestinal subjects was 35.1%. The loss to the Catende sugar estate from reduced productivity caused by schistosomiasis mansoni for the harvest season of 1978 was calculated as 0.93% of the estate's total production, or approximately US$135,000. When this figure is extrapolated to the State of Pernambuco (16 million tons of sugar total annual production), the annual loss in the state if estimated to be US$2 million.
28 citations
TL;DR: In this paper, a pipeline rheometer is described for measurement of rheological properties of the sludge, which is a complex flocculated suspension having no fixed particle dimension, shape, size distribution or surface characteristics.
Abstract: Rheological study of sewage sludge is useful for the design, operation and control of sewage treatment plants. The rheology is highly dependent on physical, chemical and biological characteristics of the sludge. A pipeline rheometer is described in this paper for measurement of rheological properties of the sludge. Primary sewage sludge is a complex flocculated suspension having no fixed particle dimension, shape, size distribution or surface characteristics. The information available so far on rheology of sewage sludge is not suitable for application in design because of the lack of data on physico-chemical characteristics of this sludge.
23 citations
TL;DR: In this article, the change in glass transition temperature and heat capacity at the glass transition have been shown to be dependent on the concentration of filler and the degree of dispersion of each filler was kept constant by using a master batch and diluting with polymer solution.
Abstract: Changes in glass transition temperature and heat capacity at the glass transition have been shown to be dependent on the concentration of filler. The polymer studied was poly (vinyl chloride-co-vinyl acetate) with 10% vinyl acetate, and the fillers were Aerosil 300, Aerosil OX50, carbon (Graphon C), aluminum oxide C, and titanium dioxide P25. The fillers were all of very small particle size, ∼ 10–50 nm. The degree of dispersion of each filler was kept constant by using a master batch and diluting with polymer solution. The Tg results show a strong influence of filler at low concentration which rises to a plateau. The change in heat capacity of the polymer at Tg diminishes with increase in filler concentration, although to a less marked extent, than the change in Tg
22 citations
TL;DR: It is concluded that pancreas, duodenum, ileum, spleen, and bone marrow, and probably liver and proventriculus, are target organs for aPP in the chicken and that the C-terminal region of aPP is involved in receptor binding.
Abstract: The problem of the physiological function of pancreatic polypeptide (PP) has been approached by attempting to identify target organs. Avian PP (aPP) labeled with 125I at either the C-terminus (aPP-C) or the N-terminus (aPP-N) was injected into fasted chickens and allowed to circulate for 3-120 min. At the end of the equilibration period, the anesthetized bird was perfused first with saline, then with Buoin's solution. Samples of fixed tissue from various organs were collected, weighed, and counted. Control experiments consisted of coinjection of unlabeled aPP to compete for receptors. The rate of disappearance of aPP-N from plasma was greater than that of aPP-C. Binding of aPP-N by spleen, duodenum, ileum, pancreas, and bone marrow was markedly reduced by coinjection of unlabeled aPP. A similar but less marked reduction in binding was found in liver and proventriculus. aPP-C gave less conclusive results. The maximal competitive effect of unlabeled PP could be achieved in most cases with 30 microgram unlabeled aPP. It is concluded that pancreas, duodenum, ileum, spleen, and bone marrow, and probably liver and proventriculus, are target organs for aPP in the chicken and that the C-terminal region of aPP is involved in receptor binding.
22 citations
TL;DR: A long-term controlled field experiment is described from northeastern Brazil, in which the molluscicide Bayluscide was used as the sole means of control against Schistosoma mansoni infection.
Abstract: A long-term controlled field experiment is described from northeastern Brazil, in which the molluscicide Bayluscide was used as the sole means of control against Schistosoma mansoni infection.Bayluscide was effective in the reduction of all of the parameters used for evaluation of the disease: incidence, prevalence, intensity of the infection (egg counts) in man, snail population (dynamics and natural infection rate) and the infectivity of natural water bodies (as measured through the exposure of sentinel mice). A less pronounced reduction of the same parameters was seen in the untreated area.Comments are made on the use of molluscicides and on the present situation in schistosomiasis control in the social and economic context of northeastern Braeil.
21 citations
TL;DR: In this article, the presence of carbon filler has been shown to cause a change in the glass transition temperature of polymers, and it is postulated that the thermal stress of these polymers is increased when filled with carbon.
Abstract: The presence of carbon filler has been shown to cause a change in the glass transition temperature of polymers. For poly(vinyl chloride) and two of its copolymers with 10 and 15% vinyl acetate an increase in Tg was observed when Graphon C Carbon was added. The increase was greater when the proportion of vinyl acetate was greater. Polar vinyl acetate units allow stronger adsorption of polymer onto the carbon. Brittle polymers such as polystyrene and poly(methyl methacrylate) showed scattered Tg's when filled with carbon. The changes were not a function of concentration. It is postulated that the thermal stress of these polymers is increased in the presence of filler.
19 citations
TL;DR: In this paper, the response of a rigid rectangular foundation block resting on an elastic half-space is determined by considering first the displacement functions for any position on the surface of an unloaded halfspace due to a harmonic point force.
Abstract: This chapter is about the response of a rigid rectangular foundation block resting on an elastic half-space. It is determined by considering first the displacement functions for any position on the surface of an unloaded half-space due to a harmonic point force. The influence of the foundation has been taken into account by assuming a relaxed condition at the interface, i.e., a uniform displacement under the foundation and that the sum of the point forces must equal the total applied force. The vertical, horizontal, and rocking motions have been considered, and numerical values for the in-phase and the quadrature components of the displacement functions are presented for a Poissons ratio of 0.25.
17 citations
01 Jan 1981-Precision Engineering-journal of The International Societies for Precision Engineering and Nanotechnology
TL;DR: A system has been designed which enables the scanning of a surface area and the obtaining of the profile height ordinates digitally, thus permitting quantitative analyses of the surface, and the ubiquitous Talysurf is designed.
Abstract: A system has been designed which enables the scanning of a surface area and the obtaining of the profile height ordinates digitally, thus permitting quantitative analyses of the surface. System hardware comprises three main units, an electronic counter unit, an independent automatically traversing and indexing tables system, and the ubiquitous Talysurf. The output of the Talysurf is connected on-line to a mini computer carrying an analogue to digital converter and removable storage cartridge discs. The practical utility of the system is manifested in its ability to scan a surface automatically without the need for modifications of any sort to the Talysurf. As data are already stored in digital form, analyses are merely carried out by appropriate software. Although the discussion centres around the basic ‘autotable’ with facilities to carry right cylinder specimens, attachments can be made available to accommodate other types of specimens as well
TL;DR: HLA-A and B locus antigens were determined in 96 affectively ill persons including 25 unipolar and 47 bipolar patients, finding possible reasons for the seemingly conflicting results found to date are briefly discussed.
Abstract: HLA-A and B locus antigens were determined in 96 affectively ill persons including 25 unipolar and 47 bipolar patients. The frequency of HLA-A2S is higher than in controls in each patient group. HLA-Bw16 is present with an elevated frequency among the unipolar patients. These differences are no longer significant when corrected for the number of antigens tested.
The literature on HLA antigens in affective illnesses is reviewed and possible reasons for the seemingly conflicting results found to date are briefly discussed.
TL;DR: In this paper, the mineral content of hair from two populations, Oriomo Papuans and Akita in Japan, which have different salt intake, were investigated, and the results showed that the zinc content of Papuan hair was significantly less than that of people living in Akita.
Abstract: Mineral (Na, K, Ca, Mg and Zn) contents in the hair from two populations, Oriomo Papuans and Akita in Japan, which have different salt intake, were investigated. Determination of minerals was conducted on untreated hair samples and hair samples washed with distilled water or ten percent acetic acid solution. The sodium content of the hair of persons living in Akita whose salt intake was in excess of 20 g/day was significantly greater than that of the hair of Papuans whose salt intake was estimated to be about 200 mg/day. The potassium level in untreated Papuan hair was significantly greater than that of the hair of people in Akita; but in washed hair the opposite was found. The sodium/potassium ratio of hair from Akita was significantly greater than that of Papuan hair in all treatments. Except when acid washing was used, no differences were observed in calcium contents. Magnesium levels did not differ whatever treatment had been applied. The zinc content of Papuan hair was significantly less than that of...
TL;DR: The results suggest the existence of an active transport system which has a limited capacity for cholesterol absorption and which requires energy for its operation in the physiological state.
Abstract: In order to study the mechanism of intestinal cholesterol absorption, the relationship between the amount of cholesterol administered and the rate of absorption was investigated by the dual isotope plasma ratio method in vivo and the ligated-loop method in situ. The energy requirement of cholesterol absorption was also observed by means of the ligated-loop method. The results obtained are summarized below. 1) Tri-phase absorption was observed by the dual isotope plasma ratio method. When less than 300 microgram of cholesterol was administered, absorption increased linearly, with the coefficient of absorption being more than 80%. When the amount administered was between 300 and 500 microgram, the absorption was constant. With the administration of more than 500 microgram, absorption increased linearly, but the coefficient of absorption decreased to approximately 55%. 2) With the ligated-loop method, a second saturation profile was obtained when between 250 and 400 microgram of cholesterol was administered to a segment. When 50 to 250 microgram of cholesterol were administered, absorption increased in proportion to the increase in cholesterol dosage. 3) The mucosal uptake of cholesterol decreased to 40-60% of the control with the addition of metabolic inhibitors such as NaN3, KCN, 2,4-DNP and ouabain, whereas the uptake of palmitate showed no significant decrease. In addition, the uptake of cholesterol decreased remarkably to 25% of the control with the lowering of body temperature from 37 degrees C to 27 C. These results suggest the existence of an active transport system which has a limited capacity for cholesterol absorption and which requires energy for its operation in the physiological state.
TL;DR: Birth weights of 42 full-term patients with congenital rubella syndrome were analyzed, finding that low-birth-weight may have a relationship with time of maternal rubella rather than with the type of defects, i.e., cataract, heart disease, and deafness.
Abstract: Birth weights of 42 full-term patients with congenital rubella syndrome were analyzed. All of these infants were products of pregnancies in which the exact dates of the maternal first day of last menstrual period and of the time of onset of the mothers' rubella rash were known. The range of time of maternal rubella associated with low-birth-weight was in the gestational age interval from 16 to 100 days. Low-birth-weight may have a relationship with time of maternal rubella rather than with the type of defects, i.e., cataract, heart disease, and deafness.
TL;DR: In this paper, high resolution RBS has been employed to measure oxidation rates, oxide stoichiometry and implant redistribution during the thermal oxidation of ion implanted silicon, and the results indicate that oxidation rates can be dramatically enhanced or retarded by small concentrations (∼1 at%) of appropriate impurity.
TL;DR: The enzyme hydrolyzes native DNA about 6-times faster than denatured DNA, producing 5'-phosphoryl and 3'-hydroxyl terminated oligonucleotides with an average chain length of about eight nucleotides, and converts double-stranded and circular DNA to relaxed and linear forms.
TL;DR: In this paper, the extent of photoinitiated polymerization of butyl acrylate has been determined using a range of sample thicknesses, for each of the sample thickness, and the optimum concentration of photo-initiator, for maximum extent of polymerisation, increases as the path length increases.
TL;DR: By analyzing the different perspectives of parents, children, educators, physicians, hospital administrators and the funding agency, it shows how self-help programs within a hospital setting are shaped by an interaction of forces.
Abstract: The current health self-help movement has its roots in the social movements of the 1960's. Frustrated with the practices and priorities of established medicine, many groups organized to meet their health needs outside the medical care system. Now self-help is becoming more attractive to health care providers. Hospitals, physicians and funding agencies are putting new emphasis on teaching self-help skills to a variety of patients.This report describes one such program established for asthmatic children and their parents in a medical center in New York City. By analyzing the different perspectives of parents, children, educators, physicians, hospital administrators and the funding agency, it shows how self-help programs within a hospital setting are shaped by an interaction of forces. The potential and limits of self-help as an instrument for social and institutional change are described. The article concludes with recommendations on how health workers can contribute to the self-help process.
15 Dec 1981
01 Jan 1981
TL;DR: A method is described to ensure quantitative measurement of dissolved mercury vapor (Hg°) in blood and urine and it is suggested that samples should be stored at 0 °C and Hg° should be determined within 60 min of collection of blood samples and within 10 min of urine samples.
Abstract: A method is described to ensure quantitative measurement of dissolved mercury vapor (Hg0) in blood and urine. Room air passed through samples of blood and urine carries with it all the dissolved Hg0 but leaves behind all the ionic mercury (Hg++). Oxidation of Hg0 to Hg++ in blood samples is completely inhibited by addition of ethanol (0.5% v/v). To minimize error due to evaporation of Hg0, it is suggested that samples should be stored at 0 degree C and Hg0 should be determined within 60 min of collection of blood samples and within 10 min of urine samples.
TL;DR: In this article, an attempt towards fulfilling that requirement by analysing engineering surfaces before and after wear, using digitized data of their three-dimensional microgeometry, is discussed.
Abstract: The problems of wear and its control, especially in the manufacturing industry, require an abiding solution if the advances predicted and being eagerly sought by many manufacturers around the world are to be accomplished To obtain such a solution, resort to fundamental understanding of the wear process is inevitable. This paper discusses an attempt towards fulfilling that requisite by analysing engineering surfaces before and after wear, using digitized data of their three-dimensional microgeometry.
TL;DR: In this article, the effect of colonisation on the infestation of intestinal parasites was examined in the subtropical lowlands of Bolivia and the variation in the extent of infestation among colonies showed the modification of this relationship by the development of cultivation and/or adjustment for living facilities which were influenced by differential colonizing processes in terms of the time elapsing since initial settlement, the type of colonization and the origin of the colonists.
TL;DR: In this paper, high resolution channeling combined with TEM was used to investigate ion implant damage, atom location and phase changes in high dose Dy +, Ar + and Sb + implanted (100) Fe.
TL;DR: In this paper, high resolution Rutherford backscattering and channeling techniques have been used to investigate the formation and stability of supersaturated solid solutions of As, Sb, In, Pb, Tl and Bi implants in (100) silicon.
Abstract: High resolution Rutherford backscattering and channeling techniques have been used to investigate the formation and stability of supersaturated solid solutions of As, Sb, In, Pb, Tl and Bi implants in (100) silicon. In all cases near-substitutional solid solubilities far exceeding maximum equilibrium solubility limits can be achieved by furnace annealing at temperatures ≤ 600°C. Details of the recrystallisation process indicate that the maximum impurity concentration which can be incorporated onto silicon lattice sites may be controlled by impurity size and associated strain effects at the amorphous-crystal boundary during epitaxial regrowth.