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Showing papers by "University of Melbourne published in 1970"


Journal ArticleDOI
TL;DR: The innervation of the anterior cerebral artery of the rat was examined by electron microscopy and by the fluorescence method for localizing adrenergic nerves and both adrenergic and cholinergic axons come into close relationship with smooth muscle cells.
Abstract: The innervation of the anterior cerebral artery of the rat was examined by electron microscopy and by the fluorescence method for localizing adrenergic nerves. Two groups of axon bundles were associated with the artery; one at the outer margin of the adventitia ( periadventitial bundles) and the other within the adventitia or at the adventitia-media border ( adventitial bundles). Periadventitial bundles consisted of nonmyelinated axons (0.1-2µ diam), some of which contained synaptic vesicles; in some bundles, myelinated axons were seen. Adventitial axons often contained many synaptic vesicles and were free of Schwann cell sheath in areas apposed to smooth muscle cells. The closest observed approach of axon to muscle cell was 800 A. No nerve fibers penetrated the medial muscle. After fixation with glutaraldehyde plus osmium, large (1000 A) granular and small (500 A) agranular vesicles were seen within many axon profiles. Small granular vesicles were rare. After permanganate fixation, terminal axons contained (besides large granular vesicles) either predominantly small granular vesicles or exclusively small agranular vesicles. Two days after sympathetic denervation, no axons containing small granular vesicles and no fluorescent fibers were seen. Adrenergic fibers were readily identified after injection of rats with 6-hydroxydopamine; small vesicles of adrenergic axons contained highly opaque granular cores, even in osmium-fixed material. Axons containing small agranular vesicles after 6-hydroxydopamine were considered cholinergic. The density of granulation of the large vesicles of adrenergic, but not cholinergic, axons was considerably enhanced following 6-hydroxydopamine. Both adrenergic and cholinergic axons come into close relationship with smooth muscle cells.

258 citations


Journal ArticleDOI
TL;DR: In this article, an asymptotic solution of these equations is obtained which describes a slowly varying solitary wave; also differential equations for the slow variations of the parameters describing the solitary wave are derived, and solved in the case when the solitary waves evolves from a region of uniform depth.
Abstract: Equations are derived for two-dimensional long waves of small, but finite, amplitude in water of variable depth, analogous to those derived by Boussinesq for water of constant depth. When the depth is slowly varying compared to the length of the wave, an asymptotic solution of these equations is obtained which describes a slowly varying solitary wave; also differential equations for the slow variations of the parameters describing the solitary wave are derived, and solved in the case when the solitary wave evolves from a region of uniform depth. For small amplitudes it is found that the wave amplitude varies inversely as the depth.

241 citations


Journal ArticleDOI
TL;DR: The adrenergic nervous system of the domestic fowl has been investigated using the Falck-Hillarp technique for the localisation of biogenic amines and the predominating catecholamine in adrenergic nerves is noradrenaline.
Abstract: The adrenergic nervous system of the domestic fowl has been investigated using the Falck-Hillarp technique for the localisation of biogenic amines. The predominating catecholamine in adrenergic nerves is noradrenaline. In the fowl, adrenergic nerves are more widely distributed than in mammals, although comparable in appearance; clumps of adrenergic ganglion cells are present throughout the viscera, particularly in the abdomen. The heart and arterial vasculature has an adrenergic innervation comparable to that seen in mammals, but the veins are frequently more densely innervated, suggesting that they may play a more active role in the regional distribution of blood and in venous return than in mammals. The respiratory system of birds shows certain peculiarities and these are reflected in the adrenergic innervation of this system. The density of the adrenergic innervation of the genital organs is dependent on age; in males the innervation of the genital ducts only shows a marked development at sexual maturity, but in females it appears to be established before hatching. These findings are discussed in terms of the function of adrenergic nerves in the different situations.

136 citations


Journal ArticleDOI
TL;DR: A prospective combined study of consecutive patients with severe pregnancy anaemia was performed in five countries and the important finding was that placental hypertrophy was associated with maternal anaemia in all centres.

128 citations


Book ChapterDOI
01 Jan 1970
TL;DR: The concept of immunological surveillance is a broad one but it is a part of the still broader concept of internal homeostasis within the mammalian body as discussed by the authors, which is not a specifically stated hypothesis susceptible to a precise experimental test; it is rather a tentative generalization that could give some logical unity to a wide range of observable phenomena.
Abstract: Publisher Summary This chapter focuses on immunological surveillance. The concept of immunological surveillance is a broad one but it is a part of the still broader concept of internal homeostasis within the mammalian body. It is not a specifically stated hypothesis susceptible to a precise experimental test; it is rather a tentative generalization that could give some logical unity to a wide range of observable phenomena. In essence, immunological surveillance is the concept that a major function of the immunological mechanisms in mammals is to recognize and eliminate foreign patterns arising in body by somatic mutation or some equivalent process. From the point of view of survival, this is important primarily as providing a means by which the appearance of malignant disease may be effectively cut short. Surveillance, if it exists, is a negative factor in the natural history of human cancer. Malignant disease is initiated by factors intrinsic to individual cells and its emergence will depend on a variety of factors in the micro-environment as well as in the cells of the proliferating clone. Immunological effects will be superimposed upon others and all that we can predict is that under such and such immunological circumstances, cancer will be more or less frequent than it would otherwise be.

124 citations


Journal ArticleDOI
TL;DR: The formation of hydrogen peroxide by group N streptococci was found to occur through the action of a reduced nicotinamide adenine dinucleotide (NADH) oxidase which catalyzed the oxidation of NADH by molecular oxygen.
Abstract: The formation of hydrogen peroxide by group N streptococci was found to occur through the action of a reduced nicotinamide adenine dinucleotide (NADH) oxidase which catalyzed the oxidation of NADH by molecular oxygen. The enzyme was activated by flavine adenine dinucleotide. Whereas some of the hydrogen peroxide formed was removed through the action of an NADH peroxidase, sufficient accumulated in media to inhibit the growth, respiration, and viability of these organisms. The amount of hydrogen peroxide which accumulated varied among strains, and this variation could be related to differences in the properties of the NADH oxidase present.

121 citations


Journal ArticleDOI
TL;DR: The effects of various drugs on the action of 6‐ OHDA indicate that this drug must be taken up by the nerves and reach a critical extragranular axoplasmic concentration before degeneration will occur; 6‐OHDA bound in the vesicles plays no part in the degenerative process.
Abstract: Summary 1 The effects of 6-hydroxydopamine (6-OHDA) on adrenergic nerves in the domestic fowl have been investigated with ultrastructural and fluorescence histochemical methods. 2 6-OHDA depletes the nerves of catecholamine, initially by displacing it from the storage vesicles. 6-OHDA enters large as well as small vesicles, indicating that large granular vesicles in adrenergic nerves are sites of amine storage. 3 Doses of 6-OHDA, insufficient to cause degeneration, still cause loading of the vesicles. 4 The effects of various drugs on the action of 6-OHDA indicate that this drug must be taken up by the nerves and reach a critical extragranular axoplasmic concentration before degeneration will occur; 6-OHDA bound in the vesicles plays no part in the degenerative process.

115 citations


Journal ArticleDOI
TL;DR: It is suggested that progressive weakening of the function of immunological surveillance is important and that this may be related to weakness of the thymus-dependent immune system, which may be dependent on exhaustion of the Hayflick limit in the cells concerned in theThymus and dependent tissues.

109 citations


Journal ArticleDOI
TL;DR: The cells of the theca externa of large, antral ovarian follicles in the rat were studied by electron microscopy, and filament‐containing cells of intermediate structure appeared to represent transitional forms between the two previous types.
Abstract: The cells of the theca externa of large, antral ovarian follicles in the rat were studied by electron microscopy. Many resembled fibroblasts, while others possessed cytoplasmic filaments and dense bodies characteristic of smooth muscle cells. Filament-containing cells of intermediate structure appeared to represent transitional forms between the two previous types. Small numbers of smooth muscle-like cells were found also around small antral follicles, and many corpora lutea possessed locally well-defined coats of smooth muscle. These observations indicate that cells with a probable contractile function are present in the theca externa of ovarian follicles in the rat. These cells may play a role in the process of ovulation.

107 citations


Journal ArticleDOI
11 Apr 1970-Nature
TL;DR: Recent work on cancer immunity suggests that the character and diversity of cell membrane antigens may be controlled by processes similar to those concerned with the origin of specific patterns in the immune system.
Abstract: Recent work on cancer immunity suggests that the character and diversity of cell membrane antigens may be controlled by processes similar to those concerned with the origin of specific patterns in the immune system.

105 citations


Book ChapterDOI
01 Jan 1970
TL;DR: The name of Th.
Abstract: The name of Th. Dobzhansky will always be associated with the concepts of heterosis and adaptive genetic polymorphisms in natural populations of sexually reproducing organisms. But the relationship between these concepts is still in part controversial and even after approximately 35 years of serious study of these phenomena in a variety of organisms, both in nature and in the laboratory, it is by no means clear how far the adaptive significance of most polymorphisms is to be ascribed to “pure heterosis” (i.e., superiority of the heterozygote in all environments) and how far to “annidation” (in the terminology of Ludwig, 1950)—i.e., an adaptive correspondence between the various genotypes present in the population and the alternative ecological niches present in the environment.


Journal ArticleDOI
01 Sep 1970-Planta
TL;DR: The relationships of wax morphology to wax chemistry and the effects of light intensity on wax development were investigated using rubbing techniques to produce nearly wax free cuticular surfaces and suggested that tube waxes originate as flat plates that fuse along one edge to form a hollow structure.
Abstract: The relationships of wax morphology to wax chemistry and the effects of light intensity on wax development were investigated using rubbing techniques to produce nearly wax free cuticular surfaces. Wax regeneration took place rapidly on leaves which were in their exponential stage of expansion, but only slowly on those that had fully expanded. The pattern of wax development suggested that tube waxes originate as flat plates that fuse along one edge to form a hollow structure.

Journal ArticleDOI
01 Nov 1970-Virology
TL;DR: The hemagglutinin and nucleocapsid protein of the A Bel strain of influenza virus, and the neuraminidase of the B Lee strain have been isolated and analysed by polyacrylamide gel electrophoresis in the presence of neutral sodium dodecyl sulfate.

Journal ArticleDOI
TL;DR: The inhibitor was found to be too unstable to isolate in pure form, but its properties in dilute aqueous solution were studied with a view to establishing its identity, and it was concluded that the inhibitor was either cyanosulphurous acid (HO(2)SCN) or cyanosULphuric acid ( HO(3) SCN).
Abstract: Lactoperoxidase (EC 1.11.1.7), an enzyme present in various mammalian glands and in their secretions, catalyses the oxidation of thiocyanate by hydrogen peroxide to form a compound that inhibits the growth, oxygen uptake and acid production of certain bacteria. This compound was found to be too unstable to isolate in pure form, but its properties in dilute aqueous solution were studied with a view to establishing its identity. At thiocyanate concentrations of approximately 1mm, formation of the inhibitor, which took place by a nonstoicheiometric reaction, was maximal when an approximately equimolar amount of hydrogen peroxide was added. Excess of hydrogen peroxide oxidized the inhibitor to sulphate and cyanate. The inhibitor displayed a polarographic reduction wave of which the half-wave potential was pH-dependent. Studies of the variation of the polarographic half-wave potential and of the u.v. extinction with pH indicated that the inhibitor existed in an acid–base equilibrium (pKa 5.1±0.1). The inhibitor decomposed by a mechanism involving H+ ions and thiocyanate, the kinetics varying according to whether the inhibitor was in its acidic or basic form. From these studies it was concluded that the inhibitor was either cyanosulphurous acid (HO2SCN) or cyanosulphuric acid (HO3SCN).

Journal ArticleDOI
TL;DR: In this paper, the pyroxene-ilmenite intergrowths were found among xenoliths from South African Kimberlites and chemical analyses of the intergrowth and their component minerals were given.

Journal ArticleDOI
TL;DR: Using improved fixation techniques and higher resolution electron microscopy, it may be possible to demonstrate gap junctions in most smooth muscle cells, which suggests intermediate gradation between close fusion and near separation into "gap junctions".
Abstract: There has been considerable interest recently in the precise structure of the membranes of closely related smooth muscle cells in various systems . Most workers have claimed that there is true fusion of the outer lamellae of apposing unit membranes (1, 2), but one note (without illustration) published in this journal has reported that the areas of close apposition of membranes of smooth muscle cells do not represent fusion but rather "gap junctions" with a separation of the outer lamellae of apposing cell membranes of about 20 A (5) . The electron micrograph presented in Fig . 1 clearly demonstrates the gap type of junction between the smooth muscle cells of the sheep ureter, although the intermembrane gap varies between 25 and 30 A in this preparation . Gap junctions were also found between heart muscle cells in the guinea pig (Fig . 2), as has also been shown for the mouse heart (4) . The fixation procedure used in this work was as follows. Tissue blocks were fixed initially with phosphate-buffered 1 % Os0 4 (pH 7.3) for 1 hr, immersed in 3 % glutaraldehyde (in water) for I hr, and then postfixed with 2% Os04 (in water) . The tissue was stained in block with uranyl acetate solution (T. Kanazeki, Y. Uehara, and M . Imaizumi, data in preparation) . Specimens were dehydrated through graded concentrations of ethanol and embedded in Epon 812 according to the method of Luft (3) . With the same fixation procedure, it was possible to demonstrate gap junctions in only very short episodes of the order of 100 A between muscle cells in the chicken gizzard (Fig. 3), in which Cobb and Bennett (1) have claimed that there is true fusion of adjacent muscle cell membranes with a wide variety of fixation procedures . Fig. 3 also demonstrates variation in thickness of the fused layer, which suggests intermediate gradation between close fusion and near separation into "gap junctions" . Using improved fixation techniques and higher resolution electron microscopy, it may be possible to demonstrate gap junctions in most smooth muscles. However, it is still not known to what extent preparative procedures alter the appearance of smooth muscle cell membrane relationships or how much variation in structure there is between different systems of the same animal, or in the same system between different animals .

Journal ArticleDOI
TL;DR: In this article, a stress exponent, n, of 1.5 was found for scandia-doped zirconia and two regimes, with n=1 and 6, were found for the yttria-dope ZrO2-6 mol% Sc2O3 (grain size ∼2 μm).
Abstract: Compression creep measurements at constant load on ZrO2-6 mol% Sc2O3 (grain size ∼1 μm), ZrO2-6 mol% Y2O3 (grain size ∼17 μm), and heat-treated ZrO2-6 mol% Sc2O3 (grain size ∼2 μm) yield activation energies of 89, 86, and 74 kcal/mol, respectively. The creep rates are linearly proportional to the inverse square of the grain size of the material. A stress exponent, n, of 1.5 was found for the scandia-doped zirconia and two regimes, with n=1 and 6, were found for the yttria-doped zirconia. These data, supported by metallographic evidence, are interpreted as showing that n=1 is associated with cation diffusion control of creep, n=6 with local propagation of inter-crystalline cracks, and n=1.5 with a transition region.

Journal ArticleDOI
TL;DR: Confounding inherent in the use of solid food or sucrose does not appear to account for negative incentive contrast effects and four dependent measures indicated that concentrations of sucrose and saccharin that produced equivalent levels of performance produced equivalent negative contrast effects.
Abstract: Thirty male hooded rats received seven sessions of barpress training with sucrose (16% or 4%) and saccharin (.10% or 1.5%) as reward, followed by a shift from 16% to 4% sucrose and.10% to 1.5% saccharin. Four dependent measures indicated that concentrations of sucrose and saccharin that produced equivalent levels of performance produced equivalent negative contrast effects. In Experiment 2, 18 male hooded rats received four sessions of barpress training with (.10% or 1.5%) saccharin under an FR 7 schedule of reinforcement followed by a shift from.10% to 1.5%. Four of the five measures indicated negative contrast effects. Confounding inherent in the use of solid food or sucrose does not appear to account for negative incentive contrast effects.

Journal ArticleDOI
TL;DR: In this paper, equine herpesviruses (EH viruses) were isolated from 9 horses in three separate outbreaks of respiratory disease, and evidence was presented that some of the horses were ill, possibly as a result of recurrent infection, and that reactivation of a persistent, latent infection may have occurred.
Abstract: Summary Equine herpesviruses (EH viruses) were isolated from 9 horses in three separate outbreaks of respiratory disease. The pattern of disease in the three stables is described and evidence is presented that some of the horses were ill, possibly as a result of recurrent infection, and that reactivation of a persistent, latent infection may have occurred. An ulcerative condition of the pharyngeal region was seen in some of the horses with EH virus infection. The cytopathogenicity for equine foetal kidney cells of the 9 EH viruses varied considerably. One isolate, EH 39 virus, which was recovered from an acute, upper respiratory tract infection, was rapidly cytopathic for equine foetal kidney cell cultures and was shown in neutralisation tests to be identical with, or closely related to equine rhinopneumonitis virus (EH virus type 1) that is associated with acute respiratory disease and abortion in other countries. More slowly cytopathic isolates were recovered from mild to subclinical upper respiratory tract infections. Evidence is presented that the property of slow cytopathogenicity is probably related to the tendency of these viruses to remain cell associated. Slowly cytopathic isolates were recovered from the nasal cavity of horse 89 on two occasions 79 days apart. One of the eight slowly cytopathic isolates, EH 86 virus, was shown to be antigenically distinct from equine rhinopneumonitis virus (EH 39 virus).

Journal ArticleDOI
TL;DR: In this article, the mean square vibrational amplitudes in ZnO and BeO were calculated for frequencies up to 4 × 1012 c/sec, and the results were in good agreement with the predictions of a simple shell model.

Journal ArticleDOI
TL;DR: A proposed mechanism for the photochemical addition of L‐cysteine to uracil with the concurrent formation of dihydrouracil is shown to proceed through the triplet excited state of uracicil which can abstract hydrogen atoms from cysteined to form diHydrouredacil.
Abstract: — A proposed mechanism for the photochemical addition of L-cysteine to uracil with the concurrent formation of dihydrouracil is shown to proceed through the triplet excited state of uracil which can abstract hydrogen atoms from cysteine to form dihydrouracil. This triplet state is the same one as that leading to photodimerization. The thiyl radicals generated add to ground state uracil molecules. The data permit a re-evaluation of the quantum yield for intersystem crossing of uracil in water which shows dimerization in aqueous solution to have a maximum efficiency of 56 per cent. The formation of the cross-adduct and dihydrouracil may be sensitized but the efficiency of the reaction is related to the ability of the sensitizer to be photoreduced and not to its triplet energy.

Journal ArticleDOI
TL;DR: Three plexuses of adrenergic nerve fibres have been distinguished in the submucosa: a dense plexus of terminal fibres innervating both the veins and arteries; a plexu consisting of innervated nodes of ganglion cells, connected by bundles of fluorescent and non-fluorescent nerves; and a pLexus of varicose and non -varicose fibres, which is not associated with ganglions.
Abstract: A detailed study of the origin and distribution of sympathetic fibres in the distal colon of the guinea-pig has been made using the fluorescent histochemical method for localizing catecholamines. The extrinsic adrenergic fibres of the colonie sympathetic nerves follow the inferior mesenteric artery and its branches to the colon. Some of the extrinsic adrenergic fibres are associated with the parasympathetic fibres of the pelvic nerves near the colon. Complete adrenergic denervation follows the removal of the inferior mesenteric ganglion or the destruction of the nerves running with the inferior mesenteric artery.

Journal ArticleDOI
TL;DR: It is suggested that cholinomimetic drugs may act on receptor sites associated with the adrenergic terminal axon and that they may facilitate or impair the release of noradrenaline and impair norad Renaline uptake.
Abstract: 1. The effects of infusions of the cholinomimetic drugs acetylcholine, methacholine, muscarine, carbachol, arecoline and pilocarpine were examined on vasoconstrictor responses of the perfused rabbit ear artery to sympathetic nerve stimulation and to injections of noradrenaline.2. The first effect of very low concentrations of acetylcholine or muscarine was a slight enhancement of responses to sympathetic nerve stimulation, but when higher concentrations of acetylcholine, methacholine, muscarine, carbachol and arecoline were infused, these vasoconstrictor responses were decreased. With still higher concentrations the responses tended to increase in size during the infusion. After stopping an infusion, the depressed vasoconstrictor responses rapidly recovered and became enhanced.3. Infusions of pilocarpine in a wide range of concentrations generally caused enhancement of responses.4. The depressant effects of cholinomimetic drugs on the responses to sympathetic nerve stimulation were antagonized by atropine. Larger concentrations of the drugs overcame the blockade by atropine.5. The effects of acetylcholine, methacholine and muscarine on the responses to sympathetic nerve stimulation were more pronounced at low than at high frequencies of stimulation.6. Vasoconstrictor responses to injected noradrenaline were enhanced by acetylcholine or methacholine, whereas responses to sympathetic nerve stimulation were decreased by the same concentrations of these choline esters.7. It is suggested that cholinomimetic drugs may act on receptor sites associated with the adrenergic terminal axon and that they may facilitate or impair the release of noradrenaline and impair noradrenaline uptake.

Journal ArticleDOI
TL;DR: In this article, a series of combined stress tests in torsion-tension space is carried out on thin-walled tubes of 1100-F commercially pure aluminium and the results are analyzed in terms of a proposed, rationally based, yield criterion constructed according to statistical reasoning.
Abstract: A series of combined stress tests in torsion-tension space is carried out on thin-walled tubes of 1100-F commercially pure aluminium. One initial and four subsequent yield loci are established to a maximum prestrain level of 14 per cent tensile plastic strain.The results are analysed in terms of a proposed, rationally based, yield criterion constructed according to statistical reasoning.It is shown that during prestrain a significant degree of geometrical distortion is undergone by the yield loci, accompanied by a strong Bauschinger effect and a flattening of part of the locus opposite to the loading point.It is found that the yield locus does not rotate during prestrain and, contrary to the case for torsion prestrain, exhibits evidence of a sharply rounded corner developing at the loading point.The proposed criterion is shown to fit the experimental results extremely well and the mechanism of distortion is explained in terms of a statistical model for work-hardening materials.

Journal ArticleDOI
TL;DR: In this article, the EH 39 virus type 1 (EH 39 virus; equine rhinopneumonitis virus) was found to be slowly cytopathic for equine foetal kidney cell cultures and serologically unrelated to the inoculated EH39 virus.
Abstract: Summary An 8-month-old filly (No. 2) developed an acute vulvo-vaginitis and respiratory disease following inoculation of equine herpesvirus (EH virus) type 1 (EH 39 virus; equine rhinopneumonitis virus) into the vestibule of the vagina. The same virus produced acute respiratory disease but not balanoposthitis following intranasal, intravenous and intrapreputial inoculation of a 12-month-old colt (No. 3). A second 8-month-old filly (No. 1) developed a mild respiratory disease but not vulvo-vaginitis following intravestibular inoculation of EH 39 virus. EH viruses that were slowly cytopathic for equine foetal kidney cell cultures and serologically unrelated to the inoculated EH 39 virus were isolated from the buffy coat cells at 3 days and from the nasal cavity at 6 days after inoculation of horse No. 1. EH virus that was slowly cytopathic and serologically unrelated to EH 39 virus was isolated at 16 days from the vagina of the filly (No. 2) that developed acute vulvovaginitis and was frequently isolated from the nasal cavities of 2 of the 3 horses for 83 days and from the nasal cavity of the third horse for 57 days under conditions that precluded reinfection from other equidae except from each other. EH viruses were recovered from the 3 horses for a further 58 days under conditions where contact with other equidae may, although was not known to, have occurred between 83 and 141 days postinoculation. It was concluded that these viruses represented a single virus type that was present in the nasal cavity (designated EH 1–6 virus) perhaps also the blood stream of filly No. 1 at the time the 3 horses were purchased and that this virus was subsequently transmitted to the vagina of 1 and the nasal cavities of the other 2 horses. Accordingly a carrier state for EH 39 virus was not shown to occur. These findings are discussed in relation to the natural history of EH virus infections. Attempts to reactivate the EH viruses to cause clinical respiratory disease, by a series of injections of adrenalin and cortisone, were inconclusive. The 3 horses showed no clinical evidence of respiratory disease when they were reinfected intranasally with EH 39 virus 360 days (1 horse) and 412 days (2 horses) after the initial infection with this virus. Abortion was produced when EH 39 virus was inoculated directly into the allantoic or amniotic cavity of a pregnant mare although naturally occurring EH virus abortion remains unrecognised in Australia.

Journal ArticleDOI
TL;DR: In two separate experiments, 40 Ss were presented with recorded sentences during each of which a click occurred, confirming the hypothesis that processing load is a function of the surface structure of sentences, although the role of minor breaks was not clear.
Abstract: In two separate experiments, 40 Ss were presented with recorded sentences during each of which a click occurred. Ss had to depress a key as soon as they heard the click. RTs were f aster when the click was located at the major syntactic break of the sentence compared with RTs to clicks not at a break. This confirmed the hypothesis that processing load is a function of the surface structure of sentences, although the role of minor breaks was not clear. A second finding was that RTs were slower when the click was in the first rather than in the second half of the sentence. This can also be explained in terms of differential processing loads.

Journal ArticleDOI
TL;DR: It has been shown that the time of decay of the EJP is not determined by inactivation of transmitter by uptake into peripheral nerve fibers, and was consistent from 30 days, which corresponds with the onset of puberty in mice.

Journal ArticleDOI
TL;DR: In this article, a numerical investigation showed that the circular tooth path is a very good approximation of the true cutter path, and the experimental trends are consistent with those predicted analytically and similar to those shown in other cutting operations.

Journal ArticleDOI
TL;DR: In this paper, the authors examined the forms of such plots and the ambiguities which arise near transitions from one regime to another and noted that ranges of temperature, stress and grain size commonly used are inadequate and serious errors in interpreting the results of creep tests will continue to be made until a better understanding of the interaction of the basic processes is developed, so as to enable the positions of transitions to be predicted.
Abstract: Attempts to identify the mechanisms operating during creep are often made by examining plots which yield apparent activation energies, or the stress or grain size-dependences of creep-rate The forms of such plots are here examined and the ambiguities which arise near transitions from one regime to another are noted The ranges of temperature, stress and grain size commonly used are inadequate and serious errors in interpreting the results of creep tests will continue to be made until a better understanding of the interaction of the basic processes is developed, so as to enable the positions of transitions to be predicted