Showing papers by "Iowa State University published in 1987"

The Choice of Organizational Form: The Case of Franchising

Abstract: Evaluates the agency problems associated with company owned versus franchised units in order to determine whether these agency considerations affect the own/franchise decision. Information on the ownership characteristics of franchise firms were gathered from 112 responses to queries sent to franchise companies listed in the 1982 Norback and Norback and the 1983 Siegel franchise directories. Monitoring problems and costs and franchising contract provisions are discussed. Results support the prediction that the owned units, which presumably entail more on-site monitoring, are located closer to central or regional headquarters than franchised units. In addition, the likelihood of franchising increases with higher monitoring costs, low initial investment costs per unit, and higher frequency of repeat customers. (SFL)

Participation in Extracurricular Activities in Secondary School: What Is Known, What Needs to Be Known?

Abstract: The paper reviews literature relating to extracurricular participation and adolescent development. Five areas are described: personal-social characteristics, academic achievement, educational aspirations and attainments, participants’ roles in activities, and environmental social context. A methodological critique and directions for future research are provided. Participation correlated with higher levels of self-esteem, improved race relations, involvement in political/social activity in young adulthood, academic ability and grades in males, educational aspirations and attainments, feelings of control over one’s life, and lower delinquency rates. However, causal relationships between participation and desirable characteristics have not been demonstrated. Students in smaller schools participate in a greater number and variety of extracurricular activities than students in larger schools. Low-ability and lower SES students are more involved in school life in smaller schools. The existing findings justify a...

Temperature effects on the universal equation of state of solids

Abstract: Recently it has been argued based on theoretical calculations and experimental data that there is a universal form for the equation of state of solids. This observation was restricted to the range of temperatures and pressures such that there are no phase transitions. The use of this universal relation to estimate pressure-volume relations (i.e., isotherms) required three input parameters at each fixed temperature. It is shown that for many solids the input data needed to predict high temperature thermodynamical properties can be dramatically reduced. In particular, only four numbers are needed: (1) the zero pressure (P=0) isothermal bulk modulus; (2)it P=0 pressure derivative; (3) the P=0 volume; and (4) the P=0 thermal expansion; all evaluated at a single (reference) temperature. Explicit predictions are made for the high temperature isotherms, the thermal expansion as a function of temperature, and the temperature variation of the isothermal bulk modulus and its pressure derivative. These predictions are tested using experimental data for three representative solids: gold, sodium chloride, and xenon. Good agreement between theory and experiment is found.

Applying Cluster Analysis in Counseling Psychology Research.

Abstract: As a research technique that has grown rapidly in applications in many scientific disciplines, cluster analysis has potential for wider use in counseling psychology research. We begin with a simple example illustrating the clustering approach. Topics covered include the variety of approaches in clustering, the times when cluster analysis may be a choice for analysis, the steps in cluster analysis, the data features, such as level, shape, and scatter, that affect cluster results, alternate clustering methods and evidence indicating which are most effective, and examples of clustering applications in counseling research. Although we make an attempt to provide a comprehensive overview of major issues, the reader is encouraged to consult several good recent publications on the topic that are especially relevant for psychologists. Cluster analysis is a classification technique for forming homogeneous groups within complex data sets. Both the clustering methods and the ways of applying them are extremely diverse. Our purpose in writing this article is to provide an introduction and a road map for applying these techniques productively to research in counseling psychology. The cluster analysis literature is huge, is scattered among many diverse disciplines, and is often arcane. We have made an attempt to cull those aspects most relevant and useful to psychologists from this literature. Most of the discussion in the psychological community about how best to apply cluster analysis to obtain robust, valid, and useful results has taken place within the past 5 years. We seem to be on the verge of a consensus, which has long been needed in an often bewildering field. In the past 30 years, a number of clustering methods, often with their own vocabulary and approaches, have sprouted within a wide variety of scientific disciplines. The earliest sustained applications were in problems of biological classification, within the field called numerical taxonomy (Sokal & Sneath, 1963). Today, clustering is applied to problems as different as the grouping of chemical structures (Massart & Kaufman, 1983) and the classification of helpful and nonhelpful events in counseling (Elliott, 1985). Computerized methods for generating clusters have been developed and made increasingly available over the last decade. Applications of clustering have mushroomed in many disciplines, including the social sciences. In an annual bibliographic search performed by the Classification Society (Day, 1986) 1,166 entries are shown for the 1985 scientific literature alone.

On the Theory of Partially Inbreeding Finite Populations. I. Partial Selfing

Abstract: It is assumed that a population has M males in every generation, each of which is permanently mated with c-1 females, and that a proportion beta of matings are between males and their full sisters or half-sisters. Recurrence equations are derived for the inbreeding coefficient of one random individual, coefficients of kinship of random pairs of mates and probabilities of allelic identity when the infinite alleles model holds. If Ft is the inbreeding coefficient at time t and M is large, (1-Ft)/(1-Ft-1)----1-1/(2Ne) as t increases. The effective population number Ne = aM/[1 + (2a-1)FIS], where FIS is the inbreeding coefficient at equilibrium when M is infinite and the constant a depends upon the conditional probabilities of matings between full sibs and the two possible types of half-sibs. When there are M permanent couples, an approximation to the probability that an allele A survives if it is originally present in one AA heterozygote is proportional to FISs1 + (1-FIS)s2, where s1 and s2 are the selective advantages of AA and AA in comparison with AA. The paper concludes with a comparison between the results when there is partial selfing, partial full sib mating (c = 2) and partial sib mating when c is large.

Effects of metals on fish behavior: a review

Abstract: Behavioral toxicity tests, if properly designed, can be used in conjunction with standard acute lethality tests, chronic full or partial life cycle tests, and early life stage toxicity tests to add ecological realism to toxicant assessments and the regulations made as an outgrowth of these assessments. Changes in certain fish behaviors, especially cough rate and avoidance reactions, are very sensitive indicators of sublethal exposure to metals. Other tests involving predator avoidance, feeding behavior, learning, social interactions, and a variety of locomotor behaviors show promise but have been insufficiently studied to judge their sensitivity or utility. No behavioral tests have been standardized and few have been verified in the field. We discuss the behavioral tests that have been used with metals, examine their sensitivity compared with standard laboratory toxicity tests, and assess the potential ecological significance of the behavioral changes observed.

Ranking from unbalanced paired-comparison data

Abstract: SUMMARY It is proposed that for ranking objects or players in an incomplete paired-comparison experiment or tournament with at most one comparison per pair, the score of a player, C, be the total number of (a) wins of players defeated by C minus losses of players to whom C lost, plus (b) C's wins minus C's losses. A tied match counts as half a win plus half a loss. More general tournaments can be treated similarly.

Development of a Standardized Test of Computer Literacy and a Computer Anxiety Index

Abstract: Definitions of the three components of computer literacy and of computer anxiety were used in a nationwide survey of instructional computing educators to develop a list of seventy competencies of t...

Influence of transposable elements on the structure and function of the A1 gene of Zea mays.

Abstract: The structure of the A1 gene of Zea mays was determined by sequencing cDNA and genomic clones. The gene is composed of four exons and three short introns. The 40.1-kd A1 protein is an NADPH-dependent reductase. Germinal derivatives of the mutable a1-m1 allele with either recessive or wild-type phenotype have been isolated. Sequence analysis of these revertant alleles indicates that frame-shift mutations abolish A1 gene function, whereas one additional amino acid within the protein sequence still allows wild-type gene expression. The presence of a second, promoter-like structure, upstream of the functional A1 gene promoter is discussed with respect to its possible involvement in differential expression of the A1 gene. The structure of the a1-m2 8004, 3456 and 4412 alleles, featuring distinguishable phenotypes in the presence of Spm(En), was also determined. In all alleles the 1080-bp-long inhibitor (I) element is located 15 bp upstream of the CAAT box of the A1 gene promoter. The unusual response of a1-m2 alleles to trans-active signals of the Spm(En) element is discussed with respect to the position of the I inserts. Also presented are data on the structure and insertion sites of transposable elements determined by cloning and sequencing of the mutable a1 alleles a1-mpapu, a1-mr 102 and a1-ml.

Multipolar response of small metallic spheres: Nonlocal theory

Abstract: The multipolar response of a small metallic sphere is studied with use of a nonlocal dielectric function. Results obtained with the hydrodynamic and Lindhard-Mermin models are presented and compared to those given by the local Drude model. We find an enhancement of the imaginary part of the multipole polarizabilities at low frequencies and pole order l${l}_{c}$, where ${l}_{c}$ is a cutoff order that corresponds to excitations at the high-wave-vector edge of the electron-hole pair continuum. The absorption coefficient for two very close spheres is calculated and the effect of nonlocality on the number and position of the multipolar absorption peaks is discussed.

Realization of power spectra from partial covariance sequences

Abstract: In this paper, we address the problem of realization of a spectral density function from incomplete information about the underlying stochastic process. The standing assumption is the availability of an (incomplete) partial sequence of covariance samples of the process. We study the set of rational extensions of this finite sequence to an infinite covariance function that agrees with the available samples. The classical theory of orthogonal polynomials (with respect to the unit circle) and the theory of moments have been utilized extensively in a variety of engineering problems, including the one we are dealing with. These have been known to provide a unifying framework for a variety of current spectral estimation techniques (maximum entropy method, Pisarenko's harmonic decomposition, etc.). In this work, we consider and study the set of all covariance realizations of dimension lower than or equal to the length of the partial sequence (and equal to the dimension of the maximum entropy realization). The ME solution is a point in this set. Other points correspond to "pole-zero" models. A general formula is obtained for recursively updated "pole-zero" models of dimension increasing with the data record. Information about the "zeros" is obtained from the asymptotic behavior of the "partial autocorrelation coefficients." Our approach combines techniques from the theory of orthogonal polynomials on the unit circle, the theory of moments, and also techniques from degree theory/topology. Our objective is to develop a theory that will provide a frame for constructing recursively "pole-zero" realizations of increasing dimension.

Simplified curve fits for the thermodynamic properties of equilibrium air

Abstract: New, improved curve fits for the thermodynamic properties of equilibrium air have been developed The curve fits are for pressure, speed of sound, temperature, entropy, enthalpy, density, and internal energy These curve fits can be readily incorporated into new or existing computational fluid dynamics codes if real gas effects are desired The curve fits are constructed from Grabau-type transition functions to model the thermodynamic surfaces in a piecewise manner The accuracies and continuity of these curve fits are substantially improved over those of previous curve fits These improvements are due to the incorporation of a small number of additional terms in the approximating polynomials and careful choices of the transition functions The ranges of validity of the new curve fits are temperatures up to 25 000 K and densities from 10 to the -7 to 10 to the 3d power amagats

Lattice dynamics of γ-Fe

Abstract: Large single crystals of fcc iron (\ensuremath{\gamma} phase) were grown in situ and used to study the lattice dynamics of this phase of Fe by standard inelastic neutron scattering techniques. The phonon dispersion curves were measured along the [00\ensuremath{\xi}], [\ensuremath{\xi}\ensuremath{\xi}0], and [\ensuremath{\xi}\ensuremath{\xi}\ensuremath{\xi}] symmetry directions at 1428 K. A selected number of phonon frequencies were also obtained at 1227 and 1640 K. We find that the measured dispersion curves are qualitatively similar to those of Ni and ${\mathrm{Ni}}_{0.3}$${\mathrm{Fe}}_{0.7}$. The 1428-K data were used to evaluate the elastic constants, the phonon density of states, and the lattice specific heat of \ensuremath{\gamma}-Fe.

Transition metal complexes with terminal carbyne ligands

Abstract: Publisher Summary This chapter discusses the chemistry of molecular carbyne complexes; there is also much interest in them as models for species that are possibly present on metal surfaces in catalytic reactions. Surfacebound methine (CH) is a proposed intermediate in the Fischer–Tropsch synthesis, and alkylidyne groups are suggested as intermediates in heterogeneously catalyzed alkyne metathesis reactions. X-Ray structure determinations of carbyne complexes show that they have very short metal–carbon bond lengths consistent with a metal–carbon triple bond. In certain cases, ∞-protons of an alkylidene ligand may be abstracted by a base to give alkylidyne compounds. Addition of electrophiles to terminal isonitrile (CNR) ligands gives aminocarbyne complexes; the analogous reaction of terminal thiocarbonyl (CS) ligands gives thiocarbynes. Fischer and Himmelreich reported the abstraction of oxygen from an anionic carbamoyl compound with SOCl 2 to give an aminocarbyne compound. Reactions of cationic carbyne compounds with nucleophiles proceed exclusively by nucleophilic attack at the carbyne carbon atom, thus providing a synthetically useful route to certain carbene complexes. The field of transition-metal carbyne chemistry has matured to the point where a great deal is known about the structure, bonding, and reactivity of the carbyne ligand.

Growth hormone treatment stimulates thymulin production in aged dogs.

Abstract: Diminished thymic morphology and function and a decreased provocative growth hormone (GH) response are characteristic of normal ageing We have previously demonstrated that bovine growth hormone (bGH) treatment of adult dogs tends to result in a rejuvenation of thymic morphology The purpose of this study was twofold: (1) to determine concentrations of thymulin (a thymic hormone) in plasma from dogs of various ages, and (2) to evaluate the effect of bGH administration on plasma thymulin concentration and thymus morphology in 'middle-aged' and 'old-aged' dogs 'Young' (4 months), 'middle-aged' (33-55 months) and 'old-aged' (63-83 months) female beagles served as subjects for this study Middle- and old-aged dogs were injected with either bGH or bovine serum albumin (control) for 1 month Thymulin concentration in plasma was determined by the rosette-inhibition bioassay An age-associated decline in the plasma concentration of thymulin was detected Plasma thymulin concentration increased in every bGH-treated dog In middle-aged but not old-aged dogs, bGH treatment resulted in rejuvenation of thymic morphological features as determined by stereological and histomorphological procedures The results suggest that exogenous GH may be useful for restoration of some immune functions in aged individuals

Hölder continuity of the gradient of solutions of uniformly parabolic equations with conormal boundary conditions

Abstract: We study solutions of the conormal derivative problem for uniformly parabolic equations in divergence form. Under weak regularity hypotheses on the operator, the global Holder continuity of the gradient of a weak solution is established. The method of proof is based on [5] and the results extend those in [7, Section V.7].