Showing papers by "York University published in 1980"

A standardized set of 260 pictures: Norms for name agreement, image agreement, familiarity, and visual complexity.

Abstract: In this article we present a standardized set of 260 pictures for use in experiments investigating differences and similarities in the processing of pictures and words. The pictures are black-and-white line drawings executed according to a set of rules that provide consistency of pictorial representation. The pictures have been standardized on four variables of central relevance to memory and cognitive processing: name agreement, image agreement, familiarity, and visual complexity. The intercorrelations among the four measures were low, suggesting that they are indices of different attributes of the pictures. The concepts were selected to provide exemplars from several widely studied semantic categories. Sources of naming variance, and mean familiarity and complexity of the exemplars, differed significantly across the set of categories investigated. The potential significance of each of the normative variables to a number of semantic and episodic memory tasks is discussed.

Innovativeness, Novelty Seeking, and Consumer Creativity

Abstract: A conceptual framework is presented that incorporates three constructs highly relevant to consumer behavior—innovativeness, novelty seeking, and consumer creativity. A fourth construct, role accumulation, is also discussed. A model of the relational linkages among these constructs is developed, together with their definitions and a methodology to develop operational measures. Research implications and applications of this conceptual framework are discussed.

The Experience of Workplace Politics

Abstract: This study investigates the perceived politicization of organizational processes and their attitudes and beliefs about workplace politics. Perceived politicization is related to characteristics of ...

Variant mitoses in lower eukaryotes: indicators of the evolution of mitosis.

Abstract: Publisher Summary Mitosis is defined as all those types of nuclear division that produce two, or rarely more, daughter nuclei, each containing a chromosome complement approximately similar to that of the original nucleus. The greatest range of variations by which mitosis is accomplished, occurs in the protistan and fungal kingdoms, some members of which are probably most similar to the ancestors of higher plants and animals. The variations in the higher organisms are secondarily derived from the division patterns of typical plants and animals. This chapter discusses the characteristics and evolution of mitosis. The efficiency of mitosis consists of two basic components; the frequency with which each daughter nucleus receives the necessary complete genome complement (genetic efficiency) and the amount of energy and materials expended in the synthesis and operation of the mitotic apparatus. The chapter also discusses the use of mitosis as a phylogenetic marker. It is applicable to all eukaryotic cells and thus is valuable across boundaries where other structures are absent on one side and present in various forms on the other side.

Evidence for HCO3− Transport by the Blue-Green Alga (Cyanobacterium) Coccochloris peniocystis

Abstract: The possibility of HCO 3 − transport in the blue-green alga (cyanobacterium) Coccochloris peniocystis has been investigated. Coccochloris photosynthesized most rapidly in the pH range 8 to 10, where most of the inorganic C exists as HCO 3 − . If photosynthesis used only CO 2 from the external solution the rate of photosynthesis would be limited by the rate of HCO 3 − dehydration to CO 2 . Observed rates of photosynthesis at alkaline pH were as much as 48-fold higher than could be supported by spontaneous dehydration of HCO 3 − in the external solution. Assays for extracellular carbonic anhydrase were negative. The evidence strongly suggests that HCO 3 − was a direct C source for photosynthesis. Weakly buffered solutions became alkaline during photosynthesis with a one-to-one stoichiometry between OH − appearance in the medium and HCO 3 − initially added. Alkalization occurred only during photosynthesis and was blocked by 3-(3,4-dichlorophenyl)-1, 1-dimethylurea, diuron. It is suggested that HCO 3 − was transported into cells of Coccochloris in exchange for OH − produced as a result of HCO 3 − fixation in photosynthesis. The inorganic C concentration required to support a rate of photosynthesis of half the maximum rate ( K m ) was 6 micromolar at pH 8.0 or, in terms of available CO 2 , a K m of 0.16 micromolar. This value is two orders of magnitude lower than reported K m values for the d-ribulose-1,5-bisphosphate carboxylase for blue-green algae. It is suggested that the putative HCO 3 − transport by Coccochloris serves to raise the CO 2 concentration around the carboxylase to levels high enough for effective fixation.

Problems in Predicting New Product Growth for Consumer Durables

Abstract: A popular model of new product diffusion is applied in an international setting. Several limitations on its use are noted: instability with limited data, environmental differences, and systematic under reporting of estimated time to attain peak level of first purchase sales.

Work Demands on Administrators and Spouse Well-Being

Abstract: This field study investigated the relationship of work demands experienced by 85 male senior administrators of correctional institutions and the well-being of their spouses. Data were collected by means of questionnaires completed independently by the husbands and their wives. The results indicated that wives whose husbands reported greater occupational demands reported (1) less marital and life satisfaction, (2) decreased social participation, and (3) increased psychosomatic symptoms and negative feeling states. In no case was wives' well-being enhanced as a function of increased occupational demands on husbands. Job demands thus had an influence beyond the workplace and into the lives of their spouses. The interaction between work and nonwork experiences for the quality of individual's lives and the interdependence of husband and wife in this regard require further consideration.

Towards an improved micronucleus test: studies on 3 model agents, mitomycin C, cyclophosphamide and dimethylbenzanthracene.

Abstract: Although the micronucleus assay has been widely used to detect chromosomal breakage in vivo, none of the protocols that have been used have been fully justified either experimentally or theoretically. Accordingly, we have studied the production of micronuclei by 3 compounds in detail, hoping that an optimal protocol could be defined. 2 factors were investigated, the time course of micronucleus production and the influence of multiple injections. The time course of micronucleus production in polychromatic erythrocytes (PCE) proved to be different for each of the chemicals studied, cyclophosphamide, mitomycin C and dimethylbenzanthracene. After a single intraperitoneal injection, for example, the maximum frequency of micronuclei occurred at ∼36 h for mitomycin C, and at ∼72 h for dimethylbenzanthracene. In no case could an increase in micronuclei be detected earlier than 10 h after injection, as would be predicted on theoretical grounds. From this we conclude, firstly, that multiple times are more valuable than multiple doses in detecting chromosomal breakage in vivo, and, secondly, that any treatment within ∼10 h of sampling is ineffective. The effect of multiple injections was also investigated directly. The conclusion that injections within 10 h of sampling are ineffective was confirmed. In general, the effect of 2 injections 24 h apart was close to the sum of the effects that the individual injections produce at the corresponding times. Obviously if this additivity is the usual situation, and more chemical can be given in multiple injections than in a single one, the sensitivity of the assay will be improved by the use of an appropriate multi-injection protocol. Multiple injections, however, were found to have subtractive effects if carried too far. Although we do not believe that we can define the most effective protocol yet, our results suggest that the following protocol should be more successful than those used previously: (1) inject intraperitoneally at 0 and 24 h, sample at 48, 72 and 96 h, (2) if a negative result is obtained, inject intraperitoneally at 0 h and sample at 30, 48 and 72 h. In each case, a positive result can be confirmed by either a repeat experiment or a dose—response study at the time of the maximum response.

The parallelism phenomenon in psychoanalysis and supervision: its reconsideration as a triadic system.

Abstract: In psychoanalytic superivision, supervisees manifest toward their supervisors many psychic patterns which parallel processes that are prominent in their interactions with their patients. The reverse influence is also observed: analyst and patient re-enact events of the supervisory situation. An expanded explanation for parallelism is offered which indicates how the structural and dynamic similarities of analysis and supervision link patient, analyst, and supervisor in a complex, multidirectional network that guarantees the emergence of this phenomenon.

The susceptibility of child witnesses to suggestion: An empirical study.

Abstract: This article deals with the reliability of child witnesses, in particular from the viewpoint that child witnesses should be treated with suspicion because their memories are very susceptible to suggestion. An experiment is reported, in which grade 3, grade 6, and college students were compared on their ability to recall events from a film, in the face of (mis)leading questions from an interrogator. The data showed that the grade 6 students were equal to the college students in memory capacity and in their ability to resist suggestion. The grade 3 students were inferior to the older subjects in these areas. However, the results from a second testing session led to the conclusion that although the younger children appeared to submit to suggestion much more readily than the older subjects, the effect of suggestion on actual memory was not significantly different for the three subject-groups. The implications of these findings are discussed with reference to the present status of child witnesses in Anglo-Saxon law systems.

Structure of a family of rat amylase genes

Abstract: The sequences of two cloned rat pancreatic amylase cDNAs comprising 95% of the mRNA sequence are reported. Analysis of cloned rat genomic DNA fragments using cloned cDNA probes indicates that the rat genome contains multiple closely related amylase genes in which the cDNA sequences are distributed within a region 9 kilobases in length and are interrupted by at least seven intervening sequences.

Effect Analysis in Structural Equation Models Extensions and Simplified Methods of Computation

Abstract: One of the great virtues of structural equation models is that they permit the quantification of causal and noncausal sources of statistical relationship. The present article discusses efficient ma...

The Search for Uniqueness and Valuation of Scarcity

Abstract: The widespread pressure toward conformity in opinion and behavior in current society has captured the attention of many social scientists. Several recent attempts to integrate diverse perspectives and findings on conformity use social exchange theory (Blau, 1964; Homans, 1961, 1974; Nord, 1969b; Secord & Backman, 1964). While integrative, the social exchange view of conformity neglects some important motives, values, and costs. For instance, our research identifies a need for distinctiveness or “uniqueness,” that is, a need to see oneself as different from one’s peers, as a prevalent determinant of behavior. Thus, the outcomes of pressures to conform may depend upon the degree and nature of competing pressures for uniqueness. Alternatively, the act of conformity may arouse or augment pressure toward the foregone alternative of establishing or maintaining the self-perception of uniqueness. The present chapter develops the latter thesis by reviewing the theory and research on uniqueness and discussing implications for the social exchange view of conformity.

The Type A Experience: Occupational and Life Demands, Satisfaction and Well-Being

Abstract: This study investigated the relationship of Type A behavior to occupational and life demands, occupational and life satisfactions, and emotional and physical health. Respondents were 127 senior administrators of correctional institutions. Data were collected via questionnaires and objective physiological and physical health assessments. Greater Type A's reported more occupational demands, more concrete stressful life events at work, greater interference of work with home and family life, and less marital satisfaction. But greater Type A's also reported more self-esteem at work, greater job involvement and organizational identification and greater life satisfaction. The latter findings highlight the resistance to behavior change by Type A men. Contrary to other studies, Type A behavior bore little relationship to emotional or physical health. Exploratory analyses relating Type A behavior to emotional and physical health did confirm previous findings when the older half of the sample (45 and above) was examined.

"Two out of three" codon reading leading to mistranslation in vivo.

Abstract: Strains of Escherichia coli were starved for asparagine or lysine in order to increase the in vivo level of mistranslation. In a relA strain, asparagine starvation increased the error frequency in elongation factor Tu to 0.12 mistake per asparagine codon, while with lysine starvation in the same strain the error frequency per lysine codon was 0.008. The pattern of isoelectric point changes in the altered protein produced is consistent with third position misreading in the AAN codon group. This high level of mistranslation is not seen in streptomycin resistant (rpsL) strains or in most relA +strains.

Interference effect of 3 Hz brain stimulation on kindling behavior induced by 60 Hz stimulation.

Abstract: Experiments were conducted to evaluate the effect of 3 Hz brain stimulation on kindling behavior induced by 60 Hz sine waves stimulation. In Experiment 1, 12 rats were subjected to 40 or 60 convulsion trials with 60 Hz stimulation and then given 36 trials of 3 Hz stimulation. When these rats were stimulated again with 60 Hz sine wave current at the same brain site, none of the rats showed a convulsion in nine test trials. The intensity of stimulation had to be increased on test trial 10 to elicit convulsions for each rat. Of 10 rats in two control groups, only 1 did not convulse during the nine test trials. In Experiment 2 the effective threshold intensity (ETI) to elicit a convulsion was determined on five separate occasions with 10 days of daily trials between determinations. On each day experimental rats were stimulated with 3 Hz current on the first and third trials and with 60 Hz current on the second trial (3-60-3 group). A steady increase in the intensity required to elicit a convulsion with 60 Hz current from ETI1 to ETI5 resulted. Rats stimulated only with 60 Hz sine waves on the second trial each day (X-60-X grou,) maintained relatively stable values from ETI1 to ETI5. In the four, 10-day blocks of trials, convulsions were suppressed in 20% to 80% of the trials over the 10 day period for the 3-60-3 group, with the greatest effect occurring after about 4 days of stimulation. This suppressive effect was prominent both with rats that were at the convulsion stage prior to the first application of 3 Hz stimulation and with rats that were at preconvulsion stages. In Experiment 3 the permanency of the suppressive effect was evaluated. Eight suppressed rats from the experimental group in Experiment 2 and 4 control rats were stimulated for 90 trials over 30 days with 60 Hz current, and ETI values were determined after each set of six trials. Four of the 8 experimental rats were convulsing at ETI1 within 20 days.

The organization of cortical microtubule arrays in the radish root hair

Abstract: Cortical microtubule arrays in the radish root hair were analyzed from reconstructions of serial ultra-thin sections in order to test extant hypotheses concerning the role of microtubules in the deposition of oriented microfibrils of cellulose. Passing away from the tip, root hairs exhibit a transition from random to oriented deposition of microfibrils at approximately 25 μm. Along the root hair, passing back from the tip, the microtubules: a) increase in number to a plateau at 25 μm; b) change their length profiles from approximately 60% less than 1 μm long in the hair tip to approximately 40% less than 1 μm long at 60 μm; c) maintain a constant pattern of angular deviation from the long axis, which is similar to the deviation pattern of the oriented wall fibrils; d) maintain a constant (approximately 70% of tubules) close (within 50 nm) proximity to the plasma membrane (PM); e) maintain a low (approximately 20%) degree of inter-microtubule proximity (i.e., within 50 nm of one another); f) show evidence for some variable long range (>50 nm) association. Fixation with glutaraldehyde in a complete microtubule polymerization medium (MTPM), or pretreatment with cytochalasin B cause an approximate twofold increase in 1. the proportion of long microtubules in the tip region and 2. microtubules within 50 nm of one another. Fixation in incomplete MTPM (without GTP) produces results similar to phosphate buffer controls. Alternative explanations for these results are examined. A new hypothesis accounting for microtubule involvement in oriented microfibril deposition is described.

The psychophysics of iconic storage.

Abstract: Some simple models of iconic storage, based on the persisting responses of photoreceptors, were tested in two experiments. Substantial changes in such physical parameters as adapting luminance, stimulus luminance, and stimulus contrast produced little or no change in the duration of partial-report performance. This is at odds with most receptoral models. It seems unlikely that any model based on receptoral persistence can accommodate the results, thus forcing one to locate the icon beyond the receptors and probably beyond the retina as a whole. Language: en

Risk Factors and Preventive Intervention in Child Psychopathology: A Review

Abstract: The paper reviews 650 recent papers on bio-psycho-social risk factors and on methods for the primary prevention of childhood psychological disorders. It summarizes recent conceptual models of primary prevention based on combatting risk factors and promoting the competences that might be eroded by these factors. A number of intervention programs are then described and discussed, focused on maternal factors, poverty, infant stimulation, mother-child interaction, and daycare and pre-school competence promotion in children with and without specific education of parents. Methods and techniques of preventive intervention are summarized—crisis intervention, development of support systems, and consultation to caregivers—and the paper then reviews specific intervention programs focused on family disruption, hospitalization and illness, transitional periods, and school failure.

Persistence of three organophosphorus insecticides in artificial ponds and some biological implications

Abstract: The persistence and biological impact of the organophosphorus insecticides, Abate®, Reldan®, and Dursban®, were studied following the application of 10 ppb to a series of artificial polyethylene-lined ponds and a single natural pond inoculated with leaf litter Disappearance of the insecticides from water could be described in terms of two phases: early posttreatment, in which rapid partitioning took place; and, a variable time period, characterized by slowly decreasing residues Of the three pesticides, Dursban was the most persistent followed by Reldan and Abate in that order The rapid initial disappearance of the pesticides from water was primarily attributable to adsorption on bottom sediments and polyethylene Polyethylene appeared to have a greater affinity for the pesticides than did the sediments However, desorption from the polyethylene contributed to residual concentrations in the water of artificial ponds for prolonged periods Dursban was most toxic to cladoceran and copepod populations Cladocerans were more sensitive to the three insecticides than were cyclopod and calanoid copepods or copepod nauplii Chlorophyll concentrations as a measure of algal biomass were always greater in ponds treated with Abate or Dursban than in untreated ponds, supporting the conclusion that algal blooms result from the elimination of Zooplankton predation It was concluded that in artificial polyethylene-lined ponds residues persisted for longer times than in natural ponds The resulting prolonged period in which Zooplankton were absent leads to an increased probability of algal blooms