Showing papers by "University of Western Ontario published in 1971"
TL;DR: In this article, closed analytical expressions for the displacement fields of inclined, finite strike-slip and dip-slink faults are given, and they may be readily used in the numerical computation of displacements, and by differentiation, strain and stress fields may be derived.
Abstract: Closed analytical expressions for the displacement fields of inclined, finite strike-slip and dip-slip faults are given. They may be readily used in the numerical computation of displacements, and, by differentiation, strain and stress fields may be derived. The expressions are valid both at the surface and at depth.
785 citations
643 citations
483 citations
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357 citations
TL;DR: Experiments indicated that unsaturated fats enhance the yield of adenocarcinomas more than saturated fats, and the possible relevance of these findings to the incidence of breast cancer in humans is discussed.
Abstract: Female Sprague-Dawley rats on semisynthetic diets containing 10% and 20% by weight of corn oil developed more mammary adenocarcinomas after treatment with a single oral dose of 7,12-dimethylbenz(α)anthracene than similar rats on diets containing only 0.5% or 5% corn oil. Experiments with 10 different fats and oils fed at the 20% level indicated that unsaturated fats enhance the yield of adenocarcinomas more than saturated fats. Fibroadenomas and adenomas were also found in small numbers in all dietary groups but the yield did not seem to be influenced by level or type of dietary fat. The possible relevance of these findings to the incidence of breast cancer in humans is discussed.
278 citations
TL;DR: The geophysical implications of this widespread post-eruption lava alteration process are discussed in this paper, where the authors conclude that it is probably possible to obtain information on the original TRM of basalts at least in many cases but that the implications for potassium-argon dating need serious investigation.
Abstract: Summary
The alteration state of basalt lavas is shown to be largely the result of the combined action of two alteration processes, deuteric oxidation and regional hydrothermal alteration. The former process is well described in the literature while the latter is shown here to be another widespread source of lava alteration. The environment of regional hydro-thermal alteration is that of the zeolite metamorphic facies, with temperatures of up to 300 °C, and abundant groundwater being the major elements. Independent and rapid spatial variation of the two alteration processes results in the wide range of observed lava properties. Microscopically undetectable titanomagnetite alteration, indicated by steady rise in strong field Curie point, is the first response of a non-deuterically oxidized basalt to regional hydrothermal alteration. With more extreme alteration, titanohematite etc. is seen to pseudomorph titanomagnetite grains. Ilmenite also shows very distinctive mineralogical changes. Initially, high deuteric oxidation specimens appear to be immune magnetically to moderate alteration but these too eventually succumb when conditions are extreme enough for the formation of prehnite in the rock.
The geophysical implications of this widespread post eruption lava alteration process is discussed. We conclude that it is probably possible to obtain information on the original TRM of basalts at least in many cases but that the implications for potassium-argon dating need serious investigation.
249 citations
TL;DR: The clinical stress machine serves as an additional aid in the detection of isolated or combined damage to ligamentous structures about the knee.
Abstract: Our clinical stress machine serves as an additional aid in the detection of isolated or combined damage to ligamentous structures about the knee. The machine has greatly assisted in the classification of chronic ligamentous damage. In the questionable gray area of medial instability, machine evaluation has been a great asset in making critical therapeutic decisions.
238 citations
TL;DR: It was concluded that a villus enlarging influence reached the intestine through the duodenal papilla and the pancreatic secretions appeared to play a major role in this influence.
Abstract: Along the rat small intestine, the size of the villi gradually decreases from a maximum in the duodenum to less than half of this size in the terminal ileum. In previous work, various villus enlarging and reducing factors present in the intestinal chyme were found to control villus size. A villus enlarging factor which appeared to reach the intestine through the duodenal papilla was presently investigated.
Transplants of duodenal papilla, together with a small segment of the duodenum, were made to isolated ileal segments and to the lower ileum. At both sites, the transplants elicited a marked villus enlargement within a month. A previous finding was that villus size decreased in isolated duodenal segments unless the duodenal papilla was present.
In the next experiments, the bile-drainage was diverted from the duodenal papilla by implanting the bile duct into an isolated ileal segment which in turn was joined to the colon. The duodenal papilla which now transmitted only pancreatic secretions was then transplanted to the ileum. The bile caused only moderate villus enlargement in the ileal segments whereas marked villus enlargement took place in the ileum receiving the pancreatic secretions.
It was concluded that a villus enlarging influence reached the intestine through the duodenal papilla. The pancreatic secretions appeared to play a major role in this influence.
230 citations
TL;DR: In this paper, a cubically convergent algorithm for the simultaneous approximation of all zeros of a polynomial is presented, where several zeros are missing and the values of some derivatives of the logarithmic derivative are known.
Abstract: Suppose all zeros of a polynomialp but one are known to lie in specified circular regions, and the value of the logarithmic derivativep?p ?1 is known at a point. What can be said about the location of the remaining zero? This question is answered in the present paper, as well as its generalization where several zeros are missing and the values of some derivatives of the logarithmic derivative are known. A connection with a classical result due to Laguerre is established, and an application to the problem of locating zeros of certain transcendental functions is given. The results are used to construct (i) a version of Newton's method with error bounds, (ii) a cubically convergent algorithm for the simultaneous approximation of all zeros of a polynomial. The algorithms and their theoretical foundation make use of circular arithmetic, an extension, based on the theory of Moebius transformations, of interval arithmetic from the real line to the extended complex plane.
TL;DR: It is proposed that at mitosis the separation of the K CEs and their attached chromosomes is initiated by a differential expansion of the nuclear envelope restricted to the region between recently divided KCEs and that expansion ofThe nuclear envelope later becomes general, resulting in a marked elongation of the nucleus.
Abstract: Mitosis in Schizosaccharomyces pombe has been followed in living cells by phase-contrast microscopy and studied in fixed and suitably stained preparations by light microscopy. Successful preservation of nuclear fine structure in this yeast, not previously achieved, has allowed us to confirm and extend the observations made with light microscopy. Without first arranging themselves on a metaphase plate, mitotic chromosomes become grouped in 2 clusters radiating, finger-like, from 2 points of attachment at opposite poles of an elongating nucleus. At these 2 sites electron microscopy reveals the presence of disk-shaped electron-dense organelles which we have called kinetochore equivalents (KCE). At mitosis the KCEs are connected across the nucleus by a narrow bundle of parallel microtubules which we refer to as the spindle. Integration of our observations has led us to propose that at mitosis the separation of the KCEs and their attached chromosomes is initiated by a differential expansion of the nuclear envelope restricted to the region between recently divided KCEs and that expansion of the nuclear envelope later becomes general, resulting in a marked elongation of the nucleus. Displacement of the nuclear contents to the ends of the elongated nucleus gives it the shape of a dumbbell. The elongation of the microtubule bundle keeps in step with the elongation of the nucleus but does not appear to be the cause of it. It may have the function of keeping the separated KCEs rigidly apart. During mitosis the nucleolus persists and stretches out within the unbroken envelope of the nucleus as it elongates. Towards the end of division equal amounts of nucleolar material are found in the rounded ends of the dumbbell-shaped nucleus. The break up of the dumbbell shape into daughter nuclei seems to involve the breaking of its tenuous middle part and a pivoting of its 2 ends in opposite directions. In the course of our work on mitosis we have become aware of features in the cytoplasm of growing S. pombe cells which are described here for the first time. The cells invariably contain several prominent vacuoles containing an extremely electron-dense material which stains metachromatically with toluidine blue and may be polyphosphate. The mitochondria are of special interest for 2 reasons. First, because they have unique mesosome-like membrane invaginations and secondly, because a mitochondrion is regularly associated with the single KCE by the side of the interphase nucleus, as well as with each one of the 2 KCEs that occupy opposite ends of the intranuclear spindle during mitosis.
TL;DR: In contrast to these two well-known methods, this article employed a third method, namely, to expose a person to information designed to make him consciously aware of states of inconsistency that exist chronically within his own value-attitude system below the level of his conscious awareness.
Abstract: 1. Contemporary social psychologists generally agree that a necessary prerequisite to cognitive or attitude change is the presence of a state of imbalance or inconsistency. Two major experimental methods generally employed to create such a psychological state are (a) to induce a person to engage in behavior that is incompatible with his attitudes and values and (b) to expose him to information about the attitudes or values of significant others that are incompatible with his own attitudes and values. In contrast to these two well-known methods, we have employed a third method, namely, to expose a person to information designed to make him consciously aware of states of inconsistency that exist chronically within his own value-attitude system below the level of his conscious awareness. 2. While the main theoretical focus of contemporary social psychology is on the concept of attitude and on theories of attitude change, the present focus is on the concept of value and on a theory of value change. This shift from attitudes to values is made on the assumption that values are more fundamental components within a person's makeup than attitudes and, moreover, that values are de-
TL;DR: In this paper, the theoretical relationship between the stress conditions causing liquefaction in simple shear and triaxial compression tests, based on several different failure criteria, is investigated.
Abstract: The merits and limitations of laboratory simple shear and triaxial compression tests, conducted under cyclic loading conditions, are analyzed. In addition the theoretical relationships between the stress conditions causing liquefaction in simple shear and triaxial compression tests, based on several different failure criteria, are investigated. Finally data are presented for 35 sites where liquefaction is known to have occurred or not occurred during earthquakes, providing a means for evaluating the stress conditions causing liquefaction of sands in the field. It is shown that both analytical and experimental evidence, as well as field data, suggest that most laboratory triaxial compression test data, expressed in terms of σ dc /(2σ a ) should be reduced by a factor of 0.55 to 0.7, depending on the density of the soil and the duration of the earthquake, in order to determine values of τ Dhv /σ' o causing liquefaction during earthquakes under field conditions. Considerable judgment is involved in evaluating such relationships, and data from field studies may provide the basis for evaluating the liquefaction characteristics of sands.
TL;DR: In this paper, the steady axially symmetric incompressible flow past a sphere is investigated for Reynolds numbers, based on the sphere diameter, in the range 0·1 to 40.
Abstract: The steady axially symmetric incompressible flow past a sphere is investigated for Reynolds numbers, based on the sphere diameter, in the range 0·1 to 40. The formulation is a semi-analytical one whereby the flow variables are expanded as series of Legendre functions, hence reducing the equations of motion to ordinary differential equations. The ordinary differential equations are solved by numerical methods. Only a finite number of these equations can be solved, corresponding to an approximation obtained by truncating the Legendre series at some stage. More terms of the series are required as R increases and the present calculations were terminated at R = 40. The calculated drag coefficient is compared with the results of previous investigations and with experimental data. The Reynolds number at which separation first occurs is estimated as 20·5.
TL;DR: It is shown that words or letters presented successively to either visual field are more readily recognized in the right visual field and visuospatial location, a predominantly right hemisphere function, is more accurate in the left visual field.
Abstract: THE two cerebral hemispheres in man function differently; the left hemisphere has a special function in processing language material while the right hemisphere has a special function in the perception of visuospatial material1,2. It has been suggested3 that these functional differences are reflected in perceptual asymmetries favouring the visual field opposite the predominant hemisphere. As a consequence of left hemisphere specialization in processing language material, words or letters presented successively to either visual field are more readily recognized in the right visual field. Conversely, visuospatial location, a predominantly right hemisphere function, is more accurate in the left visual field4.
TL;DR: Hippocampal rhythmical slow activity (RSA) and neocortical low voltage fast activity occurred during walking, jumping and swimming, but irregular hippocampal activity and cortical spindling occurred during immobility and shivering (when it occurred in the absence of other movement).
TL;DR: Steketee's Elasticity Theory of Dislocations is generalized to real Earth models in this article, taking into account self-gravitation, radial variation of elastic properties, density and gravity, initial hydrostatic stress, and the presence of the liquid core.
Abstract: Summary
Steketee's Elasticity Theory of Dislocations is generalized to real Earth models. Taken into account are; (i) self-gravitation, (ii) radial variation of elastic properties, density and gravity, (iii) initial hydrostatic stress, (iv) the presence of the liquid core. Volterra's formula for the displacement field is found to hold in the more general circumstances for slip faults.
The dilemma, previously pointed out by Jeffreys and Vicente, which arises when the Adams and Williamson condition is assumed not to hold everywhere perfectly in the core, is resolved. This result also bears on the theory of Earth tides and tidal loading.
Changes in the inertia tensor are shown to arise only from spheroidal displacement fields of degree zero and two. These fields have virtually no attenuation with distance from the fault. In the one example in which a direct comparison can be made, the present theory gives a factor of 7.5 increase over a mapped half-space theory and a factor of 2.9 increase over the result for a uniform, spherical Earth, in the contribution to secular polar shift and excitation of Chandler wobble. Calculated and observed levels appear now to be in agreement.
TL;DR: Topographic histologic changes in human enamel following treatment with several acidic adhesive conditioning agents were correlated with changes in the depth of the tissue and could be related to intrinsic differences in histology and/or solubility of the enamel.
TL;DR: In this article, the authors describe a study on the value patterns of a midwestern municipal police force, and compare police values with those of representative samples of black and white Americans.
Abstract: This article describes a study on the value patterns of a midwestern municipal police force, and compares police values with those of representative samples of black and white Americans. The data on police values support the hypotheses that personality factors and social backgrounds are more important than occupational socialization in understanding police value systems. The police values are not necessarily representative of American value patterns, either black or white, suggesting that either more differential recruitment and/or more direct resocialization procedures are needed for improving police-citizen relations in this country. Language: en
01 Jan 1971
TL;DR: Removal of the Fc portion of antibody reduced the ability of specific antibody to inhibit the specific immune response by factors of greater than 10 and sometimes as great as a l000-fold (7–9).
Abstract: Antigen-antibody complexes affect various types of cells by mechanisms which require the activity of the Fc portion of the antibody. As examples, one can cite systems involving reaginic antibodies, or complement-fixing antibodies in immune complex reactions. With immunosuppression by specific antibody, there is strong but circumstantial evidence that antibody combines with antigen, forming an antigen-antibody complex (1). Antibody may act by the simple masking of antigen and not through a negative feedback system in which the Fc portion would play an important role (as with other biological activities of antigen-antibody complexes). Favouring the simple masking of antigen are reports (2–6) that removal of the Fc portion by controlled hydrolysis with pepsin produced little, if any, effect on the immunosuppressive activity of specific antibody. Our experience has been the reverse; that is, removal of the Fc portion reduced the ability of specific antibody to inhibit the specific immune response by factors of greater than 10 and sometimes as great as a l000-fold (7–9).
TL;DR: In this paper, an analysis of smoker personality traits and brand preferences identifies relationships of significant magnitude and logical direction and highlights the crucial role of moderator variables, highlighting the importance of the moderator variables.
Abstract: An analysis of smoker personality traits and brand preferences identifies relationships of significant magnitude and logical direction and highlights the crucial role of moderator variables.
TL;DR: In this article, the eustatic changes since the maximum lowering of the ocean level during the glaciation maximum about 18,000 B.C. (20,000B.P.).
TL;DR: The present report discusses the list of alkylating agents whose action on L-cells is potentiated by caffeine, and finds caffeine strongly potentiated the lethal action of UV and the kinetics of the effect suggested that a repair process was being inhibited.
Abstract: : Studies of the mechanisms used by mammalian cells to repair DNA following UV irradiation are hampered by a lack of established cell lines which show differences in radiation sensitivity. The effect of caffeine on UV-treated mouse L-cells was studied. Caffeine strongly potentiated the lethal action of UV and the kinetics of the effect suggested that a repair process was being inhibited. Similar findings and conclusions were recently reported for caffeine and the alkylating agent mitomycin C. The present report discusses the list of alkylating agents whose action on L-cells is potentiated by caffeine.
TL;DR: In this article, the authors found that mandibular movements were induced by stereotactic stimulations of certain central neural structures in anaesthetized and lightly-anaesthetised decerebrate rabbits.
TL;DR: Both estrone and estradiol increased the uptake of progesterone by isolated uterine strips, but these increases could be accounted for entirely on the basis of the uterotrophic effects of the steroids and were not evident when expressed per mg uterine weight.
Abstract: The effects of estrone (lμg/day) and prolactin (200 μg/day), alone and in combination, on deciduomal growth in response to uterine trauma and on uptake and metabolism of pi'ogesterone by nontraumatized uteri have been investigated in ovariectomized, progesteronetreated (2 mg/day) rats. Estrone significantly increased the size of traumatized uteri, whether administered during the 3-day period of uterine sensitization, immediately before traumatization, or during the 3-day period of deciduomal growth, immediately after traumatization. Prolactin significantly increased the size of traumatized uteri in the absence of estrone, but, when administered in the presence of estrone, significantly decreased the stimulatory effect normally produced by estrone. Both estrone and estradiol increased the uptake of progesterone by isolated uterine strips, but these increases could be accounted for entirely on the basis of the uterotrophic effects of the steroids and were not evident when expressed per mg uterine weight. Ne...
TL;DR: In this paper, a detailed description of the methods currently being used by the author for production of Franck-Condon factors, densities and r-centroids for diatomic molecules is given.
Abstract: In this the first of a series of papers, a detailed description is given of the methods currently being used by the author for production of Franck-Condon factors, densities and r-centroids for diatomic molecules. These quantities are derived from realistic Klein-Dunham potentials, which have been extrapolated by means of fitted Morse type functions. Tests for accuracy of bound state wave functions are described. The suggestion of Russian workers that the potential model might be improved is discussed.