Showing papers by "University of Arizona published in 1987"

Product/Consumption-Based Affective Responses and Postpurchase Processes:

Abstract: The author examines consumer affective responses to product/consumption experiences and their relationship to selected aspects of postpurchase processes. In separate field studies of automobile own...

The cognitive unconscious

Abstract: Contemporary research in cognitive psychology reveals the impact of nonconscious mental structures and processes on the individual's conscious experience, thought, and action. Research on perceptual-cognitive and motoric skills indicates that they are automatized through experience, and thus rendered unconscious. In addition, research on subliminal perception, implicit memory, and hypnosis indicates that events can affect mental functions even though they cannot be consciously perceived or remembered. These findings suggest a tripartite division of the cognitive unconscious into truly unconscious mental processes operating on knowledge structures that may themselves be preconscious or subconscious.

Identification of an Amplified, Highly Expressed Gene in a Human Glioma

Abstract: A gene, termed gli, was identified that is amplified more than 50-fold in a malignant glioma. The gene is expressed at high levels in the original tumor and its derived cell line and is located at chromosome 12 position (q13 to q14.3). The gli gene is a member of a select group of cellular genes that are genetically altered in primary human tumors.

Direct and Indirect Effects in Linear Structural Equation Models

Abstract: This article discusses total indirect effects in linear structural equation models. First, I define these effects. Second, I show how the delta method may be used to obtain the standard errors of the sample estimates of these effects and test hypotheses about the magnitudes of the indirect effects. To keep matters simple, I focus throughout on a particularly simple linear structural equation system; for a treatment of the general case, see Sobel (1986). To illustrate the ideas and results, a detailed example is presented.

Toward an integration of cognitive and motivational perspectives on social inference: A biased hypothesis-testing model

Abstract: Publisher Summary The chapter proposes a model to integrate the cognitive and motivational perspectives on social inference. The model specifies (1) the conditions under which affective and motivational factors do and do not influence inferential processes and (2) the mechanisms through which affective and motivational processes influence inferential processes to produce biased conclusions. The chapter focuses on the role of a self-esteem motive in producing the self-serving attribution bias. This particular motive is chosen because a wide variety of theorists throughout the history of psychology have suggested that the need for self-esteem exerts a powerful influence on people's cognitions and behavior. It should be pointed out; however, the model is quite general and applicable to the mechanisms through which other motives influence inferences as well. Influenced by recent developments in cognitive psychology and information processing, the theorists focus on the way people encode and organize—the retrieve information and on the knowledge structures—transformation rules and heuristics that are used to make inferences of various kinds. The chapter briefly discusses some of the major influences on various steps in the sequence when the only goal of the process is to arrive at an accurate attribution for the observed event.

Inequality and Insurgency

Abstract: Maldistribution of land in agrarian societies is commonly thought to be an important precondition of mass political violence and revolution. Others argue that because of the difficulty of mobilizing rural populations for political protest, land maldistribution is irrelevant except as part of an inegalitarian distribution of income nationwide. These rival inequality hypotheses have significant implications with respect to the kinds of reforms likely to reduce the potential for insurgency in a society. They are tested using the most comprehensive cross-national compilation of data currently available on land inequality, landlessness, and income inequality. Support is found for the argument that attributes the greater causal import to income inequality. Moreover, the effect of income inequality on political violence is found to hold in the context of a causal model that takes into account the repressiveness of the regime, governmental acts of coercion, intensity of separatism, and level of economic development.

Spirituality and well-being in terminally ill hospitalized adults.

Abstract: Initial research into the significance of spirituality among terminally ill adults was extended. Two hypotheses were examined using three groups of 100 adults matched on age, gender, education, and religious background: a) Terminally ill hospitalized adults indicate a greater spiritual perspective than nonterminally ill hospitalized adults and healthy nonhospitalized adults. b) Spiritual perspective is positively related to well-being among terminally ill hospitalized adults. All 300 participants completed the Spiritual Perspective Scale, Index of Well-Being, and other information. Planned comparisons analysis results supported the first hypothesis; low but significant correlation lent support to the second hypothesis. Differences among groups on recent change in spiritual views also were examined; a significantly larger number of terminally ill adults indicated a change toward increased spirituality than did nonterminally ill or healthy adults.

Validation and measurement of the fundamental themes of relational communication

Abstract: A recently advanced schema for relational communication proposes as many as 12 fundamental and distinctive themes underlying relational message exchange. Reported here are the results of three measurement studies using exploratory oblique and orthogonal factor analyses and confirmatory factor analysis. These offer empirical validation for seven to 10 of the themes. Additionally, results from seven experiments using the relational communication measure provide reliability estimates and predictive validity data. The final recommended measurement instrument is a 30‐item scale incorporating eight independent themes or clusters of themes.

Molecular cloning of complementary DNA encoding the avian receptor for vitamin D.

Abstract: Vitamin D3 receptors are intracellular proteins that mediate the nuclear action of the active metabolite 1,25-dihydroxyvitamin D3 [1,25(OH)2D3]. Two receptor-specific monoclonal antibodies were used to recover the complementary DNA (cDNA) of this regulatory protein from a chicken intestinal lambda gt11 cDNA expression library. The amino acid sequences that were deduced from this cDNA revealed a highly conserved cysteine-rich region that displayed homology with a domain characteristic of other steroid receptors and with the gag-erbA oncogene product of avian erythroblastosis virus. RNA selected via hybridization with this DNA sequence directed the cell-free synthesis of immunoprecipitable vitamin D3 receptor. Northern blot analysis of polyadenylated RNA with these cDNA probes revealed two vitamin D receptor messenger RNAs (mRNAs) of 2.6 and 3.2 kilobases in receptor-containing chicken tissues and a major cross-hybridizing receptor mRNA species of 4.2 kilobases in mouse 3T6 fibroblasts. The 4.2-kilobase species was substantially increased by prior exposure of 3T6 cells to 1,25(OH)2D3. This cDNA represents perhaps the rarest mRNA cloned to date in eukaryotes, as well as the first receptor sequence described for an authentic vitamin.

Distrbution and Abstract Types in Emerald

Abstract: Emerald is an object-based language for programming distributed subsystems and applications. Its novel features include 1) a single object model that is used both for programming in the small and in the large, 2) support for abstract types, and 3) an explicit notion of object location and mobility. This paper outlines the goals of Em-erald, relates Emerald to previous work, and describes its type system and distribution support. We are currently constructing a prototype implementation of Emerald.

Addition of a channel mechanism to the ideal-observer model.

Abstract: Several authors have measured the detection ability of human observers for objects in correlated (nonwhite) noise. These studies have shown that the human observer has approximately constant efficiency when compared with a nonprewhitening ideal observer. In this paper we add a frequency-selective mechanism to the ideal-observer model, similar to the channel mechanism that has been demonstrated through experiments that measure a subject's ability to detect grating stimuli. For a number of detection and discrimination tasks, the nonprewhitening ideal-observer model and the channelized ideal-observer model yield similar performance predictions. Thus both models seem equally capable of explaining a considerable body of psychophysical data, and it would be difficult to devise an experiment to determine which model is more nearly correct.

The Course and Prognosis of Different Forms of Chronic Airways Obstruction in a Sample from the General Population

Abstract: We examined the course and prognosis in subjects selected from the general population who had chronic airflow obstruction at the time of their enrollment in a longitudinal epidemiologic study. Mortality and the rate of change in lung function were analyzed in relation to the initial clinical characteristics of the subjects. Twenty-seven subjects with symptoms and signs of asthma (Group I) had a higher survival rate and a much lower rate of decline in pulmonary function than the 45 subjects in Group III, whose clinical characteristics were more compatible with an emphysematous form of chronic obstructive pulmonary disease (COPD). The 10-year mortality among subjects in Group III (non-atopic smokers without a history of asthma) was close to 60 percent, whereas it was only 15 percent in Group I (atopic subjects or nonsmokers with known asthma). The mean overall rate of decline in forced expiratory volume in one second was 70 ml per year in Group III but less than 5 ml per year in Group I. Forty-five patients (Group II) who did not clearly fit into either Group I or III had intermediate values for survival and decline in pulmonary function. Previous data on mortality from COPD and the rate of progression of the condition, although compatible with our findings in patients who had an emphysematous form of disease, are not applicable to those with an asthmatic-bronchitic form. Better control of the progression of asthmatic bronchitis with therapy may explain its more favorable prognosis.

Isolation of Cryptosporidium oocysts and sporozoites using discontinuous sucrose and isopycnic Percoll gradients.

Abstract: Techniques for the large-scale isolation of Cryptosporidium oocysts and sporozoites, obtained from the feces of experimentally infected Holstein calves, were developed employing discontinuous sucrose gradients and isopycnic Percoll gradients. The oocyst recovery method utilized 2 sequential discontinuous sucrose gradients followed by 1 Percoll gradient. Recovered oocysts were essentially free of debris and bacteria and represented 34% of the original oocyst suspension. Sporozoites were recovered from excystation mixtures on a single Percoll gradient. Sixty-three percent of the original sporozoites were recovered with 2.2% contamination by intact oocysts and virtually no oocyst walls. Experimental investigations dealing with the biology of Cryptosporidium and host immune responses to cryptosporidiosis have been imped- ed by the absence of an efficient technique yield- ing contaminant-free oocysts and sporozoites in large numbers. Recently reported oocyst recov- ery techniques (Current and Haynes, 1984; Heine et al., 1984) have been based on the Sheather's flotation method used to isolate other coccidian oocysts. Other methods designed to concentrate oocysts for diagnostic purposes (Willson and

Facilitating group creativity: Experience with a group decision support system

Abstract: :This paper reports on the results of research on the use of a group decision support system (gdss) for idea generation and analysis within a planning and decision laboratory environment. Our experience to date in the use of the idea generation models suggests that the technology does significantly influence the planning process. The automated version of the brainstorming model appears to neutralize many of the group effects that have been responsible for poor performance of group brainstorming in the past. Anonymity is maintained and group members appear to express their true feelings without fear of social disapproval. In addition, the automated idea generation models appear to neutralize the effects of an authority hierarchy in the group. The models allow parallel processing of ideas and prevent one group member from dominating the group discussion. All ideas are automatically recorded in the computer and are stored within the knowledge base for use throughout the planning process.Several facto...

An independent method for determining the age of the universe

Abstract: An age of 9.3 + or - 2.0 Gyr is derived for the Galactic disk on the basis of comparisons between the sudden drop in the observed luminosity distribution and theoretical evolutionary white dwarf models and allowance for a mean prewhite-dwarf lifetime of 0.3 Gyr. To obtain the age of the universe, the time between the big bang and the first appearance of stars in the Galactic disk is added. The age of the universe is estimated to be 10.3 + or - 2.2 Gyr.

Evolution of species assemblages: effects of energetic constraints and species dynamics on the diversification of the north american avifauna

Abstract: Characteristics of the terrestrial avifauna of North America can be viewed as adaptations by a taxonomically, geographically, and ecologically defined assemblage of many species to the constraints imposed by its own biology and by the environment. We have identified distinctive patterns in the variation among species in population density, body size, area of geographical range, and trophic status. The patterns observed in bivariate plots of log-transformed variables can be characterized provisionally in terms of polygons that enclose combinations of the variables exhibited by species. The sides of these polygons may be either abrupt or indistinct. We suggest that sharp, clear-cut boundaries separating combinations of characteristics that species possess from those combinations that are not observed in any species are the result of absolute constraints. As a trivial example, the maximum size of the geographical range is determined by the size of the continent. A more interesting example of an apparently ab...

Stochastic theory of field‐scale fickian dispersion in anisotropic porous media

Abstract: A three-dimensional theory is described for field-scale Fickian dispersion in anisotropic porous media due to the spatial variability of hydraulic conductivities. The study relies partly on earlier work by the authors the attributes of which are briefly reviewed. It leads to results which differ in important ways from earlier theoretical conclusions about dispersion in anisotropic media. We express the dispersion tensor D as the sum of a local component d and a field-scale component Δ. The local component is assumed to be independent of velocity (which is most appropriate if it represents molecular diffusion) and its principal terms are taken to act parallel and normal to the mean velocity vector μ. The field-scale component is written as αμ, where α is a dispersivity tensor and μ= |μ|. We show that at large Peclet numbers P, the dispersivity tensor reduces to a single principal component parallel to the mean velocity, regardless of how μ is oriented. This result, valid for arbitrary covariance functions of log-hydraulic conductivity, differs from that of L. W. Gelhar and C. L. Axness (1983), according to whom the asymptotic dispersivity tensor may possess more than one nonzero eigen value. They calculate the direction of the largest principal dispersivity to be offset from the mean velocity toward the direction of least spatial correlation (or away from the stratification in typical layered media). We show that this principal dispersivity is offset in the opposite direction at small and intermediate Peclet numbers but rotates toward the mean velocity as P increases. The largest eigen value is constant and dominated by field-scale velocity fluctuations at large P values. The other two eigen values diminish asymptotically in proportion to P−1 and are controlled by d as well as by field-scale differential convection. The range of small Peclet numbers has not been previously investigated under anisotropic conditions yet is of much importance for transport in low-permeability rocks or soils. We show that at low P values all three principal dispersivities are proportional to P and thus Δ is proportional to μ2 (a phenomenon reminiscent of Taylor diffusion). When the mean velocity is inclined to the axes of anisotropy, the eigen values of Δ are neither parallel nor normal to μ. However, since D is dominated by d at small Peclet numbers, the principal dispersion coefficients are asymptotically (as P→0) parallel and normal to the mean velocity just like when P is large; their maximum deviation from these directions occurs at intermediate P values.

Male-specific, sex pheromone-selective projection neurons in the antennal lobes of the moth Manduca sexta.

Abstract: 1. A subset of olfactory projection neurons in the brain of maleManduca sexta is described, and their role in sex pheromone information processing is examined. 2. These neurons have extensive arborizations in the macroglomerular complex (MGC), a distinctive and sexually dimorphic area of neuropil in the antennal lobe (AL), to which the axons of two known classes of antennal pheromone receptors project. Each projection neuron sends an axon from the AL into the protocerebrum (Figs. 4, 7, 9, 13 and 15). 3. Forty-one projection neurons were characterized according to their responses to electrical stimulation of the antennal nerve as well as olfactory stimulation of antennal receptors (Fig. 1). 4. All neurons exhibited strong selectivity for female sex pheromones. Other behaviorally relevant odors, such as plant volatiles, had no obvious effect on the activity of these neurons (Fig. 2). 5. Two broad physiological categories were found: (a) cells that were excited by stimulation of the ipsilateral antenna with pheromones (29 out of 41), and (b) cells that received a mixed input (inhibition and excitation) from pheromone pathways (12 out of 41). 6. Of the cells in the first category, 13 out of 29 were equally excited in response to stimulation of the antenna with either the principal natural pheromone (bombykal) or a mimic of a second unidentified pheromone (‘C-15’) and were similarly excited by the natural pheromone blend (Fig. 3). 7. The remaining 16 out of 29 cells responded selectively, and in some cases, in a dose-dependent manner, to stimulation of the antenna with bombykal or C-15, but not both (Figs. 5, 6 and 8). Some of these neurons had dendritic arborizations restricted to only a portion of the MGC neuropil (Fig. 9), whereas most had arborizations throughout the MGC. 8. Of the cells in the second category, 9 out of 12 were excited by bombykal, inhibited by C-l 5, and showed a mixed response to the natural pheromone blend (Figs. 11 and 12). For the other 3 out of 12 cells, the response polarity was reversed for the two chemically-identified odors (Fig. 14). 9. Two additional neurons, which were not tested with olfactory stimuli, were tonically inhibited in response to electrical stimulation of the ipsilateral antennal nerve (Fig. 15). 10. These observations suggest that some of the male-specific projection neurons may signal general pheromone-triggered arousal, whereas a smaller number can actively integrate inputs from the two known receptor classes (Bal- and C-15-selective) and may operate as ‘mixture detectors’ at this level of the olfactory subsystem that processes information about sex pheromones.

Intercultural training for managers: A comparison of documentary and interpersonal methods

Abstract: Although much attention has been devoted to the issue of managerial training and development, little research has specifically focused on preparing managers for intercultural work. The present stud...

The evolution of instabilities in the axisymmetric jet. I - The linear growth of disturbances near the nozzle. II - The flow resulting from the interaction between two waves

Abstract: The modal distribution of coherent structures evolving near the nozzle of a circular jet was studied experimentally and theoretically, with particular attention given to the effects produced on the instability modes by transverse curvature, flow divergence, inhomogeneous inflow conditions, and the detailed shape of the mean velocity profile. Experiments were performed using a specially constructed air-jet facility; hot-wire anemometers were used in conjunction with Disa Model 55P11 sensors for flow measurements. The linear model used as a transfer function is capable of predicting the spectral distribution of the velocity perturbations in a jet. Consideration was also given to studies of leading nonlinear interactions generated by waves externally superimposed on an axisymmetric jet; theoretical predictions were verified experimentally.

Permeability for flow of interdendritic liquid in columnar-dendritic alloys

Abstract: Permeability data for the flow of interdendritic liquid in partially solid Pb−Sn and borneol-paraffin columnar-alloys are summarized. The data are used in regression analyses and simple flow models to arrive at relationships between permeability and the morphology of the solid dendrites. When flow is parallel to the primary dendrite arms, the important morphological aspects are the volume fraction liquid (g L) and the primary dendrite arm spacing (d 1). When flow is normal to the primary dendrite arms, the permeability depends upon the secondary dendrite arm spacing (d 2) as well asd 1 andg L. The parallel permeability is best described by a model based on the Hagen-Poiseuille law for laminar flow through a tube; for the normal permeability an empirical multilinear regression gives the best fit to the data. However, those models are not appropriate for extrapolations beyond the range of the available data (0.19≤g L≤0.66), particularly asg L approaches 1. For extrapolations, models based upon the Blake-Kozeny equation for flow through porous media are recommended.

Instrumentation to describe subjective sleep characteristics in healthy subjects.

Abstract: The purpose of this study was to develop and test the Verran and Snyder-Halpern (VSH) Sleep Scale, an instrument to subjectively measure sleep characteristics. Four major sleep factors and their associated characteristics were proposed for the Sleep Scale. Subjects completed three randomly ordered sleep questionnaires on three consecutive weekday mornings within the first two hours after arising. Scales included the VSH Sleep Scale, a sleep questionnaire and a sleep log. The VSH Sleep Scale had a reliability coefficient of .82 (theta). Construct validity was examined by factor analysis and correlations between Sleep Scale items and corresponding items on the two other study instruments. Scale validity also was assessed by the known groups method. Beginning support for the validity of the VSH Sleep Scale is provided.

Change as the Goal of Educational Research

Abstract: plish, and in each case we apply local knowledge to alter instructional procedures in ways that are more productive. We argue that there is nothing about the students' language or culture that should handicap their schooling; the problems some language minority students face in school must be viewed as a consequence of instructional arrangements that ensnare certain children by not capitalizing fully on their social, linguistic, and intellectual resources. We conclude by describing a research approach that builds upon what we learned from the case studies by creating community-based research sites. CLASSROOM RESEARCH, EDUCATIONAL CHANGE, BILINGUAL EDUCATION, MICROETHNOGRAPHY, VYGOTSKY, LEV S.