Showing papers by "Brigham Young University published in 1987"

Parent-Child Socialization

Abstract: The parent—child relationship initiates a child into the social world and reshapes components of the adult self-concept into identification with parental roles Much of what occurs between parents and children transforms a biological organism into a human being and confronts adults with a new set of experiences and responsibilities Through this facet of the socialization process, parents and children acquire the knowledge, attitudes, skills, values, and expectations that allow them to become increasingly integrated into new social relationships

Chromosomal Evolution and Speciation Revisited

Abstract: Many descriptive models of chromosomal evolution have been formulated over the past two decades. We review the assumptions and predictions of these models and consider some pertinent evidence. One model of adaptive divergence, the canalization model, is difficult to test, and where predictions are explicitly stated, empirical data generally do not support the model. However, few adequate data sets are available to test this hypothesis, and it deserves further study. Several process-oriented models of chromosomal speciation are reviewed with respect to genetic isolating mechanisms, the fitness components of individual rearrangements, and the permissible population structures. From the last we attempt to estimate qualitatively the expected genetic correlates of each model to maximize its testability. Theoretical and empirical inadequacies are discussed and suggestions are made for improvement. Both phyletic and spe- ciation models of chromosomal evolution have often been based on broad comparative studies of large taxonomic groups, but more precise testing will require multidisciplinary population- level studies of organisms hypothesized to be undergoing some form of chromosomally-mediated speciation or adaptive radiation. (Chromosomes; canalization; speciation.)

The role of peers in the complex etiology of adolescent drug use

Abstract: The role of peers in adolescent drug use is analyzed by integrating differential association and situational group pressure notions with propositions derived from social bond theory. The resultant causal model is tested for self-reported use of alcohol, cigarettes, marijuana, amphetamines, and depressants. The model explains 49% of the variation in combined drug use among 768 adolescents. The variables from social learning traditions have the strongest effects in the model, but associations with drug-using parents or with prodrug definitions received from parents or friends have far less impact on drug use than do associations with drug-using friends per se. It is argued that differential association with situational pressure to join others in drug use may be more relevant to adolescent drug use than are social bonds or differential association with a ratio of prodrug to antidrug definitions.

Perception of children's influence on family decision processes

Abstract: While several studies have examined the roles of husbands and wives in making decisions about products, few have examined the impact of children. This article reports the results of a 1985 study of the influence of children on families. The study examines children's influence in each of four stages of the purchase decision, for 25 products, and by age of the children. For child‐centered (e.g., toys, children's clothing, food) and child‐used products or services (e.g., vacations, restaurant choices, outside entertainment), the study shows that children are perceived as influential by most households. Older children are perceived as more influential than younger children for nearly all the products studied. The study concludes that “family” decision making is quite different from “husband‐wife” decision making.

An approach to schema integration and query formulation in federated database systems

Abstract: A language is introduced in which both schema integration and query formulation for federated database systems can be performed. The relational model is augmented with connectors that impose predicate conditions over attributes of relations either at the same or different sites. The relational model with connectors has a natural diagrammatic representation, and thus, the language has a graphical user interface. The theoretical foundation for the graphical language is algebraic. Bach algebraic operator maps a diagram (of relations with connectors) into another diagram, and every diagram represents a possible user query. Operators specifically designed to operate on incompatible schemas are introduced and formally defined. Possible domain incompatibilities are resolved by using extended abstract data types.

A New Tolerance Analysis Method for Designers and Manufacturers

Abstract: Nouvelle methode pour l'analyse des tolerances a l'usage du bureau d'etude et du bureau des methodes

Participation in Mail Ballot Elections

Abstract: LECTIONS are typically conducted on a single day during specified hours. With few exceptions, voters wishing to exercise their franchise must vote on that day at specified polling places. Although different cities or states use different ballot formats and voting systems (Rusk 1970; Walker 1966), the reliance on a single election day with voting at neighborhood locations has been a given in American politics. A major exception to neighborhood election day voting is absentee voting. Provisions for absentee voting have been liberalized in some states so that voters may now request and return their ballot through the mail (Walrath-Riley 1984). In the past few years, local governments of varying sizes have experimented with a new idea conducting an entire election by mail.2 Mail ballot elections differ from recent changes in absentee voting in that all registered voters are mailed a ballot and a return envelope. Mail ballot elections have the potential to increase voting, but do they? Are those who participate in mail ballot elections more representative than the kinds of people who vote in polling place elections? This article examines these questions in light of the elections conducted through the mails.

Adolescent Self-Esteem in Relation to Sexual Attitudes and Behavior.

Abstract: This study examines the relationship between self-esteem and sexual behavior in a high school-aged relatively conservative sample. The study is based on 1983 and 1984 samples (total n=2423) of adolescents attending public high schools in Utah New Mexico and California. Entire classes of high school students from 20 high schools were asked to participate in the study. Adolescents were aged 14-19 when the survey was conducted. The sample was about 2/3 female and about 3/4 white. Attitudes about premarital sex were measured by answers to a question asking for the respondents attitude toward teenagers having sexual relations before marriage. Possible answers were 1) always wrong 2) usually wrong 3) neither right nor wrong 4) usually all right or 5) always all right. Sexual intercourse experience was measured by answers to the question of whether the respondent had ever had sexual relations once or more than once. Religious affiliation and activity were asked in the survey along with many other questions about demographic characteristics and family relationships. Self-esteem was measured using Rosenbergs scale. Study results are consistent with the normative context hypothesis: in groups with more conservative norms (Mormons frequent church attenders) the relationship between self-esteem and sexual intercourse experience is negative but there is no significant relationship between these variables in groups with less conservative norms. The direction of the relationship also depends on personal beliefs; the correlation between sexual intercourse experience and self-esteem is negative among those who believe that it is wrong for teenagers to have sex before marriage and it is positive among those who believe that premarital sex is all right.

Responses of the western spruce budworm to varying levels of nitrogen and terpenes.

Abstract: An agar diet study using western spruce budworm populations from Idaho and New Mexico was carried out to determine the effects of varying concentrations of nitrogen, beta-pinene, and bornyl acetate on larval growth and survival. Increased availability of nitrogen resulted in increased larval growth rate and survival to the adult stage. Larval growth rates from the Idaho population were higher on the high-nitrogen diet than were growth rates from the New Mexico population. The high level of beta-pinene improved larval growth at the high-nitrogen concentration. Bornyl acetate significantly reduced larval growth at both the low and high levels of nitrogen although the effect was greatest with the high-nitrogen diet. High bornyl acetate concentrations also significantly reduced survival to the adult stage. At high-nitrogen levels, a high concentration of bornyl acetate reduced larval growth rates and adult survival to a level similar to that occurring at the low nitrogen and low bornyl acetate concentrations.

Effects of physical disturbance and canopy cover on attached diatom community structure in an Idaho stream

Abstract: A field experiment was conducted to determine the effect of disturbance frequency on diatom communities established on artificial substrates within an open canopy site and a closed canopy site of a 3rd order stream. The open canopy site (OCS) had a total of 80 diatom taxa colonizing the substrates, while the closed canopy site (CCS) had only 55 taxa. Cluster analysis revealed that the two sites had distinct diatom communities, although the most common species were similar between sites. There was no effect of disturbance frequency on species diversity (H') at OCS, however species diversity significantly decreased as disturbance frequency increased at CCS. At OCS, Amphora perpusilla increased in abundance as disturbance frequency increased, while Navicula lanceolata abundance decreased as disturbance increased. At CCS, Cocconeis placentula v. euglypta remained dominant regardless of disturbance frequency. The results suggest that some diatom species may be ‘shade adapted’, which may explain the site-specific responses. In addition, diatom growth-forms may explain the within site taxon-specific responses to disturbance. For example, Achnanthes sp. and Cocconeis sp., small horizontal forms, were predominant on the high disturbance substrates. Vertical or large horizontal forms may be mechanically removed by frequent physical disturbance allowing such small horizontal forms to become abundant. Frequent disturbance, by maintaining the community in an early stage of development, directly influences the diatom assemblage on rocks in streams.

Model selection: some generalized distributions

Abstract: Many models have been used to represent the distributions of random variables in statistics, engineering, business, and the physical and social science. This paper considers two, four-parameter generalized bea distributions that include nearly all the models actually used as special or limiting cases. Properties and the interrelationships among these distributions are considered. Expressions are reported that facilitate parameter estimation and the analysis of associated means, variances, hazard functions and other distributional characteristics. Estimation procedures corresponding to different data types are considered. Maximum likelihood estimation is used and the value of the likelihood function provides and important criterion for model selection. The relative performance of the various models is compared for several data sets.

Can Programmers Reuse Software

Abstract: An experiment asked programmers untrained in reuse to evaluate component reusability. They did poorly. Are reusability's promises hollow? Or are there some answers?

Correlation and prediction of ternary excess enthalpy data

Abstract: Methods for predicting ternary excess enthalpies from excess enthalpy data for the three binary mixtures involved are examined and tested for forty-two sets of ternary data. In order to study the relation between the performance of the methods and the characteristics of the components in the mixture, the sets of data were classified into four groups according to the chemical nature of their components. The asymmetric equations proposed by Scatchard, Toop, and Hillert are shown to provide accurate predictions. The ratio of the standard deviations between experimental and predicted excess enthalpies and the maximum absolute value of this magnitude is 0.05 or less for most of the systems. These equations are asymmetric with respect to the numbering of components. A rule is given for selecting which component is to be designated as component 1 for systems showing endothermic mixing, exothermic mixing, or a combination of endothermic and exothermic mixing. Correlation methods are also examined and a partial differential approximant is proposed to represent the ternary contribution to the excess enthalpy.

Chromatography with supercritical fluids.

Abstract: In supercritical fluid chromatography (SFC) the mobile phase is neither a gas nor a liquid, but is a supercritical fluid. As a result of the unique properties of supercritical fluids, SFC is rapidly becoming a prominent separation technique for the analysis of reactive, thermally labile, and nonvolatile compounds. This article reviews the history, instrumentation, and practice of the technique. Particular emphasis is placed on the different programming methods that allow elution to be selectively controlled in ways that are unique to SFC.

Fourier transform mechanical analysis for determining the nonlinear viscoelastic properties of polymers

Abstract: Fourier Transform Mechanical Analysis (FTMA) has been used to study the strain amplitude dependent nonlinear dynamic mechanical properties of two elastomer compounds, nitrile rubber (NBR) and Neoprene, at various frequencies up to 750 Hz. Basic theory and experimental results are presented for one-dimensional isothermal single frequency simple shear deformation. The Green-Rivlin constitutive equation was used to model the observed behavior. The energy dissipation mechanism and a physical meaning for the material functions in the Green-Rivlin representation have also been examined. The stress Fourier spectrum contained terms at the input frequency and its higher harmonics. It can qualitatively indicate the type of mathematical mode that best describes the observed behavior. The first harmonic storage and loss moduli showed strong dependence on the strain amplitude and frequency. The FTMA methodology presented can be used to systematically conduct nonlinear dynamic mechanical studies on any polymer. It can provide enough insight which, along with a knowledge of the molecular structure, may indicate a path for developing a better representative continuum constitutive model of these complex materials.

High frequency supply system for gas discharge lamps and electronic ballast therefor

Abstract: The invention is both a system for supplying high frequency alternating current to gas discharge lamps, such as fluuorescent lamps, and the like and a unit that can be placed in or adjacent to a lighting fixture to convert a direct current supply into high frequency AC and also provide the ballast needed for operation of the gas discharge lamps. This unit contains a symmetrical, class B, push-pull current-limited, tuned-collector, sinusoidal oscillator which is self starting, highly efficient and stable over a wide range of input voltage, with or without load. The number of parts is a minimum and the parts are relatively low cost, the power losses are very low and the system operates at high power factor with low acoustic and radio noise and low flicker. The system may derive the current from a commercially available source at any voltage and phase but preferably three phase primary of a building transformer can convert this into six phase at the output terminals which can be converted to DC of low ripple even without filtering. From the central building supply, it is possible to send AC at suitable voltage to subcenters in the building for rectification, inversion and use in lighting fixtures but preferably there is a single rectifier adjacent to the main transformer and the DC at proper voltage is distributed to the fixtures where the ballast unit is installed in a fixture to supply the lamps in it with the high frequency AC. However, one ballast unit can serve, in many instances, more lamps than a single fixture holds and it is necessary in such instances to supply the high frequency AC from one fixture to another and this can be done with only two wires. The invention also provides means for dimming the lights, for supplying heating current to lamp filaments at high voltage at the start and much reduced voltage after the arc has been struck in the lamps served by the ballast unit, and this reduction in filament current takes place automatically without switches, resistsors or other expensive and energy consuming means. The transformers used in the practice of the invention may also be used to supply the building with AC for customary appliances, incandescent lighting, and the like.

Legal remedies for spousal abuse: Victim characteristics, expectations, and satisfaction

Abstract: Since 1980 legal remedies for spouse abuse have been established in various forms in every state. Social service agencies and shelters currently encourage victims to utilize restraining orders which now carry criminal consequences for the batterer, yet little empirical data have been reported concerning their use. The present paper describes two research studies-one conducted in Dane County (Madison area), Wisconsin, the other in Sacramento County, California-that provide new helpful information for these referring agencies and offer findings which reflect which victims use these legal remedies, what their expectations are, and how satisfied the victims were with the results. A final section discusses implications for change or clarification in policy, process, and education on the use of these legal remedies.

Comparative evaluation of factors involved in Fe stress response in tomato and soybean

Abstract: Iron‐efficient and Fe‐inefficient tomato (Lycopersicon esculentum Mill; T3238FER and T3238fer, respectively) and soybean (Glycine max (L.) Merr.; A7 and T203, respectively) were grown in modified Hoagland solutions with varying levels of Fe (0, 0.025, 0.05, and 0.75 mg Fe L‐1). The release of H+ ions, reductants and reduction of Fe3+ to Fe2+ by the root, and concentration of nutrients in plant leaves and roots were measured to determine if these factors interact during the Festress response mechanism. The FER tomato responded to Fe stress by increasing H ion and reductant release concurrently with increased reduction of Fe3+ by the roots; all three reached maximum levels at the same time (day 7). Iron‐stressed A7 soybean responded first with increased H+ ion release and reduction by the roots, while reductant release lagged about 1 day behind. In both cases, increased concentration of leaf Fe corresponded to the time of maximum Fe‐stress response. The Fe‐inefficient T3238fer tomato and T203 soybe...