Showing papers by "York University published in 1975"

Applied multiple regression/correlation analysis for the behavioral sciences

Abstract: Contents: Preface. Introduction. Bivariate Correlation and Regression. Multiple Regression/Correlation With Two or More Independent Variables. Data Visualization, Exploration, and Assumption Checking: Diagnosing and Solving Regression Problems I. Data-Analytic Strategies Using Multiple Regression/Correlation. Quantitative Scales, Curvilinear Relationships, and Transformations. Interactions Among Continuous Variables. Categorical or Nominal Independent Variables. Interactions With Categorical Variables. Outliers and Multicollinearity: Diagnosing and Solving Regression Problems II. Missing Data. Multiple Regression/Correlation and Causal Models. Alternative Regression Models: Logistic, Poisson Regression, and the Generalized Linear Model. Random Coefficient Regression and Multilevel Models. Longitudinal Regression Methods. Multiple Dependent Variables: Set Correlation. Appendices: The Mathematical Basis for Multiple Regression/Correlation and Identification of the Inverse Matrix Elements. Determination of the Inverse Matrix and Applications Thereof.

Can Precession Power the Geomagnetic Dynamo

Abstract: Summary The power requirement of a stationary geomagnetic dynamo driven by some agency external to the core (e. g. precession) is equal to the ohmic dissipation in the core, Q1. For a dynamo in which differential rotation is important we show that Q1ασ1−2, where σ1∼ 5 × 105 ohm−1 m−1 is the electrical conductivity of the core. Estimates of Q1 for kinematic dynamo models range from 109 to over 1012 Watts, depending on the particular regenerative scheme characterizing the dynamo. Precessional power input to the magnetic field can be estimated in terms of the electromagnetic part of the core-mantle coupling and the tiltover angle (inclination of the core angular momentum vector to that of the mantle). We correct Stacey's estimate of core-mantle coupling to take into account the diurnal frequency of precession-induced flow relative to the mantle, and show that the power available from precession to stir the core cannot exceed 108 W if the core flow remains stable. As a caution against the widespread uncritical acceptance of Malkus’ claims to have demonstrated the energetic adequacy of precession-driven hydromagnetic turbulence, we enumerate the mathematical and physical errors which cast doubt on his theoretical arguments.

Catechol estrogen formation in the central nervous system of the rat.

Abstract: Conversion of estradiol and estrone to catechol estrogens by rat hypothalamic tissue but not by the cerebral cortex was demonstrated from the incubation of these tissues with estradiol-23H and estrone-23H and monitoring the incorporation of tritium into water. Direct evidence for this transformation was obtained by isolating the labelled phenazine derivative of 2-hydroxyestrone after hypothalamic incubation with estrone-4-14C. (Endocrinology 96: 1054, 1975)

The Affinity of Catechol Estrogens for Estrogen Receptors the Pituitary and Anterior Hypothalamus of the i n Rat

Abstract: The purpose of these experiments was to evaluate the potential for interaction between 2-hydroxyestrone and 2-hydroxyestradiol and estrogen receptors in rat pituitary and anterior hypothalamus. The 150,000 × g supernatant fractions of these tissues were prepared, the estrogen receptor-site concentration was measured, and the relative abilities of unlabelled estradiol, estrone, 2-hydroxyestradiol and 2-hydroxyestrone to compete with [3H]- estradiol for estrogen binding sites was determined. From these results, and the previously determined association constant for [3H]estradiol, 10l0M–1 the association constants of the other estrogens were calculated. The introduction of the 2-hydroxy group caused only a modest reduction in the affinity of these estrogens for the receptors. The association constants of the 2-hydroxy derivatives were within one order of magnitude of those of the parent compounds. These results demonstrate the potential for interaction between catechol estrogens and estrogen receptors in rat...

Effect of 2-Methylcitrate on Citrate Metabolism: Implications for the Management of Patients with Propionic acidemia and Methylmalonic aciduria

Abstract: Effect of 2-Methylcitrate on Citrate Metabolism: Implications for the Management of Patients with Propionic acidemia and Methylmalonic aciduria

Role of the biogenic amines in the reversal of cycloheximide-induced amnesia.

Abstract: Amnesia was induced by pretraining injections of cycloheximide (CYC) in a food motivated discrimination reversal task. Magnitude of amnesia varied as a function of the amount of training on both the initial discrimination and the reversal and also as a function of the length of intertrial interval used on both the reversal and the test. Memory spontaneously recovered 48 hr. following reversal training. Recovery from amnesia was induced by pretesting injections of d-amphetamine and 2 monoamine oxidase inhibitors, pargyline and catron. This enhanced performance was a true recovery of the memory and not a result of enhanced learning or increased arousal. Depletion of catecholamines by alpha-methyl-para-tyrosine, a tyrosine hydroxylase inhibitor, and diethyldithiocarbamate, a dopamine beta hydroxylase inhbitor, resulted in an amnesia quantitatively and qualitatively similar to amnesia induced by CYC. These data support the hypothesis that CYC-induced amnesia is mediated via central catecholamines.

The frequency of contact sensitivity in North America 1972–74 North American Contact Dermatitis Group

Abstract: Three thousand subjects in North America were patch-tested with 19 allergens. The most frequent sensitizers observed include nickel sulfate, caine mixture, potassium dichromate, balsam of Peru, thimerosal, ethylenediamine hydrochloride, paraphenylenediamine and thiram. The prevalence data compared with an earlier study indicates that the initial allergens reported warrant their continued inclusion in a routine patch test screening series in North America.

Memory retrieval from long and short lists.

Abstract: Reaction time in Sternberg9s memory retrieval task with both short and long lists is a bilinear function of list length, changing slope at the limits of memory span. Separate long-term and short-term retrieval processes are implied. An alternative one-process model expressed by a logarithmic function is also considered.

A Comprehensive Re-Analysis of the O$_{2}$(B $^{3}\Sigma _{\text{u}}^{-}$-X $^{3}\Sigma _{\text{g}}^{-})$ Schumann-Runge Band System

Abstract: The emission spectrum of O$\_{2}$ has been excited, recorded and measured between 2116 and 5663 angstrom. Of the 7700 emission lines which were measured, 5400 have been assigned to 87 bands of the B $^{3}\Sigma \_{\text{u}}^{-}$-X $^{3}\Sigma \_{\text{g}}^{-}$ Schumann-Runge system of O$\_{2}$. Many of these are reported for the first time. A computer-based Loomis-Wood method has been used to assign all of these measurements to unambiguous transitions from which a self-consistent set of molecular constants has been derived. Molecular constants for the b$^{1}\Sigma \_{\text{g}}^{+}$-X $^{3}\Sigma \_{\text{g}}^{-}$ atmospheric red system of O$_{2}$ have been recalculated. A critical assessment has been made of the molecular constants derived from all previous analyses of the Schumann-Runge system.

Measurements of the electronic transition moments of C2-band systems

Abstract: Electronic transition moments of seven C2 singlet and triplet band systems, which are in the 0.2 to 1.2 micron spectral region, have been measured. The measurements were made in emission behind incident shock waves in C2H2-argon mixtures. Narrow band-pass radiometers were used to obtain absolute measurements of shock-excited C2 radiation from which absolute electronic transition moments are derived by a synthetic spectrum analysis. New results are reported for the Ballik-Ramsay, Phillips, Swan, Deslandres-d'Azambuja, Fox-Herzberg, Mulliken, and Freymark systems.

Lidar polarization studies of the troposphere.

Abstract: The polarization properties of lidar backscattering from the atmosphere have been measured using a ruby system operating at 694.3 nm and 347.2 nm. Linearly polarized signals are transmitted, and multiple receiver channels simultaneously sample the return with polarizers oriented parallel and perpendicular to the transmitted polarization. It is found that the polarization of the scattered signal varies substantially with meteorological conditions and that the signals can be employed to derive useful information about the atmospheric conditions.

Parasexual genetic analysis of aggregation-deficient mutants of Dictyostelium discoideum.

Abstract: One hundred and thirty-nine independent, nitrosoguanidine-induced mutants blocked early in development were isolated in two haploid strains of D. discoideum. Forty of these developmental mutants were completely aggregation-deficient on bacterial lawns (Class I mutants) and these mutants were selected for parasexual genetic analysis. By fusing the Class I mutants with developmentally-competent strains the developmental mutations in 39 of these mutants were shown to be recessive; the remaining mutation appeared to be partially dominant. Complementation analysis of the developmental mutations in the Class I strains identified 5 complementation groups. Statistical analysis of the complementation data suggests that there are approximately 40 genes in this organism which will completely block aggregation when mutated and perhaps as many as 150 genes involved in some aspect of the aggregation process. Linkage analysis of 18 Class I developmental mutations revealed that 10 of these mutations map in linkage group II at a minimum of 5 loci.

The Effect of an Introductory Economics Course on Student Political Attitudes

Abstract: So much has been done in terms of measuring the impact of economics courses on student knowledge and understanding of facts, concepts and principles, and so little research has dealt with the possible effects on student political attitudes, that this study by Scott and Rothman should be of great interest to economics instructors. The authors address themselves to George Stigler's assertion that “the education of an economist makes the person who receives it more conservative.” They report on the use of their own “Social Opinion Questionnaire” and how it was employed to investigate “the different effects, if any, introductory economics and introductory psychology have on opinions related to economic issues.”

Extraversion and pain.

Abstract: According to Eysenck's (1957, 1960, 1967) theory of personality, extroverts are posited as having higher pain thresholds and greater pain tolerance than introverts. The evidence for these hypothesized relationships is reviewed. Findings appear inconclusive in both cases. Probability pooling (Mosteller & Bush, 1954) is therefore performed, grouping the comparable studies and carrying out overall tests of significance. Results support the hypothesized relationships between extraversion and pain threshold and between extraversion and pain tolerance. Possible reasons why certain studies failed to find these results are discussed.

Storage and retrieval properties of dual codes for pictures and words in recognition memory.

Abstract: Storage and retrieval properties of pictures and words were studied within a recognition memory paradigm. Storage was manipulated by instructing subjects either to image or to verbalize to both picture and word stimuli during the study sequence. Retrieval was manipulated by representing a proportion of the old picture and word items in their opposite form during the recognition test (i.e., some old pictures were tested with their corresponding words and vice versa). Recognition performance for pictures was identical under the two instructional conditions, whereas recognition performance for words was markedly superior under the imagery instruction condition. It was suggested that subjects may engage in dual coding of simple pictures naturally, regardless of instructions, whereas dual coding of words may occur only under imagery instructions. The form of the test item had no effect on recognition performance for either type of stimulus and under either instructional condition. However, change of form of the test item markedly reduced item-by-item correlations between the two instructional conditions. It is tentatively proposed that retrieval is required in recognition, but that the effect of a form change is simply to make the retrieval process less consistent, not less efficient.

City Size, Economic Diversity, and Functional Type: The Canadian Case

Abstract: It is widely accepted that increased city size brings greater industrial diversification. Nevertheless the results presented in studies which have tested this assertion are somewhat inconclusive, since doubts arise concerning the fitness of the methods used to express industrial diversification in quantitative terms. This paper reviews certain features of existing methods, describes two measures which are believed to meet certain

On Being Present to the Mind: A Sketch for the History of an Idea

Abstract: I want to discuss a doctrine and a concept in theory of knowledge which has various manifestations from at least the seventeenth to the early twentieth century. The concept is that of direct or immediate cognition, the doctrine says that only what is like mind can be directly or immediately present to mind. This doctrine raises the question of how we can know things other than ourselves and our experiences: the concept of direct presence most usually had the consequence of making our knowledge of the world indirect, uncertain, or impossible. The directly present must in some way inform us about the indirectly present.