Showing papers by "Brigham Young University published in 1994"

Associations between Parental Psychological and Behavioral Control and Youth Internalized and Externalized Behaviors

Abstract: In this study, psychological control of children was conceptually and empirically distinguished from behavioral control. Further, it was demonstrated as hypothesized that psychological control was more predictive of adolescent internalized problems, and that behavioral control was more predictive of externalized problems. Subjects were 473 fifth-, eighth-, and tenth-grade males and females from a Southern suburb. Control was measured by the Child Report of Parent Behavior Inventory and the Colorado Self-Report of Family Functioning Inventory. Problem behaviors were measured with the Child Behavior Checklist. First- and second-order factor analyses discriminated psychological and behavioral control, and structural equation analyses demonstrated the differential prediction of internalized and externalized problems. These last analyses were conducted using youth-reported data and validated using a subsample of 227 mother-youth pairs.

Entrepreneurship and Family Business: Exploring the Connections:

Abstract: This article explores how the family Influences an entrepreneur's career. There are various points In time where family and entrepreneurial dynamics intersect. These Include: (1) early experiences In the entrepreneur's family of origin; (2) family Involvement and support of early start-up activities; (3) employment of family members In the new venture; and (4) involvement of family members In ownership and management succession. The article explores each of these four areas and suggests research questions that need to be explored to develop a better understanding of the relationship between entrepreneurs and their families.

Convergence of the Cahn-Hilliard equation to the Hele-Shaw model

Abstract: We prove that level surfaces of solutions to the Cahn-Hilliard equation tend to solutions of the Hele-Shaw problem under the assumption that classical solutions of the latter exist. The method is based on a new matched asymptotic expansion for solutions, a spectral analysis for linearizd operators, and an estimate for the difference between the true solutions and certain approximate ones.

Optimization of coupled systems: a critical overview of approaches

Abstract: A unified overview is given of problem formulation approaches for the optimization of multidisciplinary coupled systems. The overview includes six fundamental approaches upon which a large number of variations may be made. Consistent approach names and a compact approach notation are given. The approaches are formulated to apply to general nonhierarchic systems. The approaches are compared both from a computational viewpoint and a managerial viewpoint. Opportunities for parallelism of both computation and manpower resources are discussed. Recommendations regarding the need for future research are advanced.

DNA sequence from Cretaceous period bone fragments.

Abstract: DNA was extracted from 80-million-year-old bone fragments found in strata of the Upper Cretaceous Blackhawk Formation in the roof of an underground coal mine in eastern Utah. This DNA was used as the template in a polymerase chain reaction that amplified and sequenced a portion of the gene encoding mitochondrial cytochrome b. These sequences differ from all other cytochrome b sequences investigated, including those in the GenBank and European Molecular Biology Laboratory databases. DNA isolated from these bone fragments and the resulting gene sequences demonstrate that small fragments of DNA may survive in bone for millions of years.

Psychological consequences of athletic injury among high-level competitors.

Abstract: Injury prohibiting continued athletic participation has been hypothesized to have a predictable emotional impact on athletes (Rotella & Heyman, 1986). However, the psychological impact of injury has not been well documented. This study examined the psychological reactions to injury among 343 male collegiate athletes participating in 10 sports. All athletes were assessed using measures of depression, anxiety, and self-esteem during preseason physical examinations. Injured athletes along with matched controls were later assessed within one week of experiencing an athletic injury and 2 months later. A 4 × 3 (Injury Status x Time of Testing) repeated measures multivariate analysis of variance (DM MANOVA) revealed that injured athletes exhibited greater depression and anxiety and lower self-esteeem than controls immediately following physical injury and at follow-up 2 months later. These findings supported the general observation that physically injured athletes experience a period of emotional distre...

Matching messages to motives in persuasion: A functional approach to promoting volunteerism.

Abstract: This study examined a functional strategy for investigating audience responses to motivationally-based persuasive appeals. It was predicted that people exposed to advertisements informing them how they could satisfy personally relevant motivations through volunteering (i.e., functionally matched messages) would judge these ads to be more persuasive, more emotionally positive, and would report being more likely to volunteer than people exposed to advertisements unrelated to their personally relevant motivations (i.e., functionally mismatched messages). These predictions were confirmed in an experiment wherein participants whose attitudes toward volunteerism served a Social Adjustive, Value Expressive, Utilitarian, Knowledge, or Ego Defensive function viewed advertisements promoting volunteerism that either matched or mismatched their personally relevant motivations. Results confirmed predictions as participants responded more favorably to the functionally matched than mismatched messages. The implications of this research for understanding the mechanisms by which functionally matched messages exert persuasive influence and the ramifications of the research for the practice of volunteerism are discussed.

Patient perceptions of nursing care: an emerging theory of interpersonal competence.

Abstract: Nurse-patient interactions were examined to identify elements of interpersonal competence among nurses from the perspective of patients. Forty patients and 12 nurses participated in this qualitative study at a private acute care hospital. Two-hundred and forty-five observations were completed. Open-ended questions were utilized in 85 audio-taped semi-structured interviews. Data collection and analysis occurred simultaneously using the constant comparative method. Four major processes emerged from the data to provide the framework for the themes: 'translating', 'getting to know you', 'establishing trust', and 'going the extra mile'. In the 'translating' theme, patients expressed satisfaction with the nurse-patient interaction when nurses informed, explained and instructed on specific aspects of treatment, and taught general principles of care. The nurses' personal sharing, kidding and clicking appeared as important processes in 'getting to know you'. Patients reported confidence and trust when nurses took charge and appeared to enjoy their work. The theme of 'going the extra mile' included friendship and providing care beyond that expected. The processes provide a framework for an emerging theory of interpersonal competence.

A Review of Selected Triassic to Early Cretaceous Ferns

Abstract: After becoming nearly extinct during the Permian, the ferns began a slow recovery during the Triassic as the climate of the earth moderated. As a result, a considerable number and variety were present and widely distributed during the Jurassic and Early Cretaceous. However, with the rapid expansion of the angiosperms during the Late Cretaceous, the ferns once again became reduced in variety and greatly restricted in distribution. Some of the Mesozoic ferns are rather primitive and obviously are closely related descendants of Paleozoic taxa. Such ferns are assigned mostly to the Marattiaceae, Guaireaceae, Osmundaceae, and Gleicheniaceae. The majority of the Mesozoic ferns, however, are distinctive and appear to have originated during that era. These fossil ferns generally fit into modern orders and families such as the Matoniaceae or the Dipteridaceae. In some cases, it is difficult to clearly distinguish some of the Mesozoic ferns from living genera.

A Bayesian approach to auto-calibration for parametric array signal processing

Abstract: A number of techniques for parametric (high-resolution) array signal processing have been proposed in the last few decades. With few exceptions, these algorithms require an exact characterization of the array, including knowledge of the sensor positions, sensor gain/phase response, mutual coupling, and receiver equipment effects. Unless all sensors are identical, this information must typically be obtained by experimental measurements (calibration). In practice, of course, all such information is inevitably subject to errors. Several different methods have been proposed for alleviating the inherent sensitivity of parametric methods to such modelling errors. The technique proposed in the present paper is related to the class of so-called auto-calibration procedures, but it is assumed that certain prior knowledge of the array response errors is available. This is a reasonable assumption in most applications, and it allows for more general perturbation models than does pure auto-calibration. The optimal maximum a posteriori (MAP) estimator for the problem at hand is formulated, and a computationally more attractive large-sample approximation is derived. The proposed technique is shown to be statistically efficient, and the achievable performance is illustrated by numerical evaluation and computer simulation. >

The ethnobotanical approach to drug discovery: strengths and limitations.

Abstract: For pharmaceuticals ranging from digitalis to vincristine the ethnobotanical approach to drug discovery has proven successful. The advent of high-throughput, mechanism-based in vitro bioassays coupled with candidate plants derived from pain-staking ethnopharmacological research has resulted in the discovery of new pharmaceuticals such as prostratin, a drug candidate for treatment of human immunodeficiency virus, as well as a variety of novel antiinflammatory compounds. Not all Western diseases are equally likely to be recognized by indigenous peoples. Gastrointestinal maladies, inflammation, skin infections and certain viral diseases are likely to be of high saliency to indigenous healers, whereas diseases such as cancer and cardiovascular illness are unlikely to be easily diagnosed by indigenous peoples. Yet indigenous remedies may indicate pharmacological activity for maladies such as schizophrenia, for which the biochemical mechanisms have yet to be discovered. Ethnopharmacological information can be used to provide three levels of resolution in the search for new drugs: (1) as a general indicator of non-specific bioactivity suitable for a panel of broad screens; (2) as an indicator of specific bioactivity suitable for particular high-resolution bioassays; (3) as an indicator of pharmacological activity for which mechanism-based bioassays have yet to be developed.

The Nano Processor: a low resource reconfigurable processor

Abstract: Reconfigurable logic systems approach the performance of application-specific integrated circuits (ASICs) while retaining much of the generality of conventional computing systems through reconfiguration. Unfortunately, the development of these systems, unlike conventional software systems, is hardware-intensive, requiring significant hardware development time. One way to introduce a more flexible development approach is to implement a customizable stored-program processor. For a given application, the designer can develop customized hardware to increase performance and then control the sequencing and operation of this hardware with software. Development time can be significantly reduced because conventional software development tools, e.g. assemblers and compilers, can be used to quickly develop new applications on the customized processor. This paper presents the Nano Processor, a fully customizable reconfigurable processor, together with its integrated assembler, that has been successfully implemented on the Xilinx 3000 series field programmable gate array (FPGA). >

Potential Contributions of Organizational Behavior to the Study of Family-Owned Businesses

Abstract: Over the past decade there has been increasing interest in the study of familyowned businesses by those in a variety of fields and disciplines. Scholars from such diverse fields as family therapy, clinical psychology, sociology, management, history, and economics have begun to recognize the pervasiveness of family businesses and the importance of understanding their unique dynamics and contributions to the world's economies. Scholars in my own field, organizational behavior, are also beginning to recognize the importance of family businesses and are starting to develop theories and conduct research on topics related to family firms. The purpose of this article is to: (1) provide a brief overview of the field of organizational behavior; (2 ) discuss why family business has been a neglected subject in the field; (3) present various theories in the field and discuss their possible application to family firms; and (4) outline how researchers and practitioners might contribute to developing better theory and practice for family firms.

Ultrasonic enhancement of antibiotic action on gram-negative bacteria.

Abstract: The effect of gentamicin upon planktonic cultures of Pseudomonas aeruginosa, Escherichia coli, Staphylococcus epidermidis, and Staphylococcus aureus was measured with and without application of 67-kHz ultrasonic stimulation. The ultrasound was applied at levels that had no inhibitory or bactericidal activity against the bacteria. Measurements of the MIC and bactericidal activity of gentamicin against planktonic cultures of P. aeruginosa and E. coli demonstrated that simultaneous application of 67-kHz ultrasound enhanced the effectiveness of the antibiotic. A synergistic effect was observed and bacterial viability was reduced several orders of magnitude when gentamicin concentrations and ultrasonic levels which by themselves did not reduce viability were combined. As the age of the culture increased, the bacteria became more resistant to the effect of the antibiotic alone. Application of ultrasound appeared to reverse this resistance. The ultrasonic treatment-enhanced activity was evident with cultures of P. aeruginosa and E. coli but was not observed with cultures of gram-positive S. epidermidis and S. aureus. These results may have application in the treatment of bacterial biofilm infections on implant devices, which infections are usually more resistant to antibiotic therapy.

The combinatorial Riemann mapping theorem

Abstract: The combinatorial Riemann mapping theorem is designed to supply a surface with local quasiconformal coordinates compatible with local combinatorial data. This theorem was discovered in an at tempt to show that certain negatively curved groups have constant curvature. A potential application is that of finding local coordinates on which a given group acts uniformly quasiconformally. The classical Riemann mapping theorem may also be viewed as supplying local coordinates (take a ring and map it conformally, by the classical theorem, onto a right circular cylinder; pull the resulting flat coordinates back to the ring as canonical local coordinates). This coordinatization role is disguised in the classical case by the fact that a Riemann surface comes preequipped with local coordinates in the desired conformal class. In the combinatorial case we begin with a topological surface having no presupplied quasiconformal structure and our task is that of discovering the local coordinates (again by pulling coordinates back from an appropriate right circular cylinder). The combinatorial data are supplied by coverings of the surface called shinglings. A shingle is a compact connected set. A shingling is a locally finite cover of the surface by shingles. (A shingling is like a tiling except that shingles are allowed to overlap while tiles usually do not overlap.) A shingling may be viewed as a combinatorial approximation to the surface. A given shingling, being locally finite, gives only a first approximation to a local quasiconformal structure on the surface. The total structure can only be determined by a sequence of finer and finer shinglings. The problem becomes that of

Social Values and Salesperson Performance: An Empirical Examination:

Abstract: Although social values have been used increasingly in consumer research, their utility in sales management research has received little attention. Using a national sample of industrial salespeople, the authors evaluate several hypotheses, developed from social adaptation theory and a theoretical framework of values domain, regarding the incremental ability of the List of Values (LOV) to predict salesperson performance beyond adaptive selling (ADAPTS) and customer orientation (SOCO). The LOV shows promise as a tool by which salesperson performance can be predicted. Managerial implications are discussed, and suggestions for future research are presented.

An epidemiological study of attention-deficit hyperactivity disorder and major depression in a male prison population.

Abstract: One hundred two inmates were interviewed and tested to determine epidemiological rates of attention-deficit hyperactivity disorder (ADHD) and depression in an adult male prison population. The Beck Depression Inventory, Hamilton Rating Scale, and four measures to assess childhood and adult ADHD were completed. The two disorders were diagnosed independently. Diagnosable ADHD was found to occur in 25.5 percent of the inmates, and major depression occurred in 25.5 percent of the inmates. A significant relationship between ADHD and depression was found to exist (p < .001). Having identified a major mental health problem in the prison population, implications include a need for further diagnosis and treatment of these disorders within a prison setting. The relationship between depression and ADHD also needs further examination.

FPGA-based stochastic neural networks-implementation

Abstract: Reconfigurable field-programmable gate arrays (FPGAs) provide an effective programmable resource for implementing hardware-based artificial neural networks (ANNs). They are low cost, readily available and reconfigurable-all important advantages for ANN applications. However, FPGAs lack the circuit density necessary to implement large parallel ANNs with many thousands of synapses. This paper presents an architecture that makes it feasible to implement large ANNs with FPGAs. The architecture combines stochastic computation techniques with a novel lookup-table-based architecture that fully exploits the lookup-table structure of many FPGAs. This lookup-table-based architecture is extremely efficient: it is capable of supporting up to two synapses per configurable logic block (CLB). In addition, the architecture is simple to implement, self-contained (weights are stored directly in the synapse), and scales easily across multiple chips. >

Density enhancement of a neural network using FPGAs and run-time reconfiguration

Abstract: Run-time reconfiguration is a way of more fully exploiting the flexbility of reconfigurable FPGAs. The run-time reconfiguration artificial neural network (RRANN) uses ran-time reconfiguration to increase the hardware density of FPGAs. The RRANN architecture also allows large amounts of parallelism to be used and is very scalable. RRANN divides the back-propagation algorithm into three sequential executed stages and configures the FPGAs to execute only one stage at a time. The FPGAs are reconfigured as part of normal execution in order to change stages. Using reconfigurability in this way increases the number of hardware neurons a single Xilinx XC3090 can implement by 500%. Performance is effected by reconfiguration overhead, but this overhead becomes insignificant in large networks. This overhead is made even more insignificant with improved configuration methods. Run-time reconfiguration is a flexible realization of the time/space trade-off. The RRANN architecture has been designed and built using commercially available hardware, and its performance has been measured. >

The morality of software piracy: a cross-cultural analysis

Abstract: Software piracy is a damaging and important moral issue, which is widely believed to be unchecked in particular areas of the globe. This cross-cultural study examines differences in morality and behavior toward software piracy in Singapore versus the United States, and reviews the cultural histories of Asia versus the United States to explore why these differences occur. The paper is based upon pilot data collected in the U.S. and Singapore, using a tradeoff analysis methodology and analysis. The data reveal some fascinating interactions between the level of ethical transgression and the rewards or consequences which they produce.

Learning science in a cooperative setting: Academic achievement and affective outcomes

Abstract: A learning unit in earth science was taught to high school students, using a jigsaw-group mastery learning approach. The sample consisted of 73 students in the experimental group and 47 students who learned the topic in an individualized mastery learning approach. The study lasted 5 weeks. Pretests and posttests on academic achievement and affective outcomes were administered. Data were treated with an analysis of covariance. The results show that students of the experimental group achieved significantly higher on academic outcomes, both normative and objective scores. On the creative essay test, the differences in number of ideas and total essay score were not significant between the groups, although the mean scores for number of words were higher for the individualized mastery learning group. On the affective domain, jigsaw-group mastery learning students scored significantly higher on self-esteem, number of friends, and involvement in the classroom. No differences were found in cohesiveness, cooperation, competition, and attitudes toward the subject learned. The results are discussed through the evaluation and comparison of the two methods of instruction used in this study. The cooperative learning movement began in junior high schools as part of the desegregation process, aiming at facilitating positive ethnic relations and increasing academic achievement and social skills among diverse students (Aronson, Stephan, Sikes, Blaney, & Snapp, 1978; Sharan & Hertz-Lazarowitz, 1980; Slavin, 1980). However, elementary teachers quickly recognized the potential of cooperative methods, and such methods were adopted freely in elementary schools before becoming widespread on the junior and senior high level. It has only been during the past few years that application of cooperative learning has been studied extensively with these older students. Cooperative learning methods generally involve heterogeneous groups working together on tasks that are deliberately structured to provide specific assignments and individual contributions from each group member. Cognitive as well as social benefits are expected, as students clarify their own understanding and share their insights and ideas with each other as they interact within the group (Deutsch, 1949). Experiments in the science laboratory have always required students to work in groups of two to four, due to the constraints of experimental processes and limited equipment and sup- plies. Thus, science courses are a natural curriculum area for examining cooperative learning practices. Now that cooperative methods are being refined to develop particular capabilities in the students, science teachers need to examine ways of structuring specific tasks to achieve the academic, affective, and socialization goals for their students. Although most of the studies of cooperative learning in the high school science classroom have centered around the cognitive outcomes of achievement testing and process skills, affective and social outcomes are also significant with students of this age. But few studies in science classes have attempted to assess such aspects of students' progress. As part of a previous revision, the science faculty at the high school where this study was conducted developed an exemplary individualized mastery learning (1ML) program for teaching science. This program seemed to alleviate the severe motivational problems and the extreme individual differences among the students in this rural/bhe-collar community. Students learned to work independently on their science studies. They had almost no lectures and few large group activities. As they worked through their assignments, however, they were free to interdct with other students. Looking in on a typical class, one would see several clusters of two or three students working together, sometimes tutoring each other, sometimes just talking through an assignment. Yet at least half of the class members would be working all alone. The importance of the overall social setting in the classroom as it relates to learning (Bruner, 1986, p. 86) and the central function of social interaction as learning occurs (Vygotsky, 1978, p. 106) seemed to have been ignored. Therefore, group mastery learning (GML), a cooperative learning tech- nique, was suggested as an antithesis to IML for teaching science over short periods. The cooperative mode of instruction considers learning as a cognitive as well as a social process, where students interact with each other as well as the teacher. To bring the social dimension back to science classrooms, the researchers chose to imple- ment GML in Grades 1 I and 12. The goal of the study was to investigate the GML's impact of the method on the individual student's academic achievement, creativity, self-esteem, and number of friends and on the overall learning environment of the classrooms. The researchers were also concerned with the students' attitudes toward earth science, the course being taught at the time of the experiment. Both cognitive and affective outcomes for students who participated in the cooperative GML approach were compared with outcomes for students who studied the same topic in an IML approach. The study addressed a number of questions related to academic and nonacademic outcomes of the two methods of study. First, it sought to determine whether academic achievement of the students taught in the cooperative GML mode would be different from the achievement of students who learned in an individualized method. Second, it sought to determine whether gains or losses would be seen in nonacademic outcomes, such as classroom learning environment, social relations, and students' self-esteem experienced by the students. The results of this study may support more use of cooperative learning in high school science.

The Conversion of SO2 to Sulfate in the Atmosphere

Abstract: The atmospheric chemistry responsible for the conversion of SO2(g) to particulate sulfate in areas impacted by anthropogenic emission of SO2 is reviewed. The major reaction mechanism for the homogeneous conversion process in the absence of clouds or fog is the oxidation of SO2(g) by the hydroxyl radical. The rate of this conversion process increases with both increasing temperature and relative humidity. Correlations are described for the effects of these two variables on the conversion process, and equations given which correlate all of the available literature data for the homogeneous conversion process in ambient atmospheres. The conversion of S(IV) to sulfate via aqueous solution chemistry in clouds and fog is more complex and dependent on several variables, including concentrations of the principal oxidants (hydrogen peroxide and ozone), ammonia, droplet size and composition, and meteorology. The gas-phase homogeneous conversion process can vary from less than 1% SO2(g) converted per hour to a maximum of about 10% converted per hour at high temperature and relative humidity. In contrast, the rate of conversion of S(IV) to sulfate in the aqueous-phase homogeneous process is controlled by mixing and reactant limitations, rather than kinetic considerations. The process can involve 100% SO2 converted per hour under optimum conditions. Consequences of the various conversion processes on environmental quality are briefly illustrated with a discussion of the impact of sulfate-containing aerosols on PM10 concentrations and visibility degradation.

Greenland ice-sheet surface properties observed by the Seasat-A scatterometer at enhanced resolution

Abstract: For 3 months in 1978, the 14.6 GHz Seasat-A scatterometer (SASS) measured the normalized microwave-radar back-scatter coefficient of the Earth’s surface for the purpose of estimating near-surface vector winds over the ocean. SASS also made back-scatter measurements over land and ice regions; however, the application of this data has been limited due to the low (50 km) resolution of the measurements. Using a new technique for generating 6 km enhanced-resolution SASS images of the radar back-scatter characteristics, we present a study of the 1978 condition of the Greenland ice sheet. We derive a time-series of back-scatter images spanning the period July–September 1978. These images show the extent of summer ablation along the ice-sheet periphery. Using the data and models relating firn structure and condition to radar back-scatter characteristics, we delineate and map the seasonal extent of zones which appear to correspond to dry-snow, percolation, wet-snow, and ablation facies, over virtually the entire ice sheet. The results provide a base line with which to compare current (ERS-1) and future Greenland radar maps of snow-and ice-surface conditions.