Showing papers by "Wichita State University published in 2002"

Creative Self-Efficacy: Its Potential Antecedents and Relationship to Creative Performance

Abstract: Using data from two different firms, this study tested a new construct, creative self-efficacy, tapping employees' belief) that they can be creative in their work roles. Results support the discriminant validity of the construct and indicate that job tenure, job self-efficacy, supervisor behavior, and job complexity contribute to creative efficacy beliefs. Creative self-efficacy also predicted creative performance beyond the predictive effects of job self-efficacy. Differences in results between white-collar and blue-collar samples suggest considerations for both theory and practice.

The Y2 Isochrones for α-Element Enhanced Mixtures

Abstract: We present a new set of isochrones in which the effect of the α-element enhancement is fully incorporated. These isochrones are an extension of the already published set of Y2 Isochrones (our Paper I), constructed for the scaled-solar mixture. As in Paper I, helium diffusion and convective core overshoot have been taken into account. The range of chemical compositions covered is 0.00001 ≤ Z ≤ 0.08. The models were evolved from the pre-main-sequence stellar birthline to the onset of helium burning in the core. The age range of the full isochrone set is 0.1-20 Gyr, while younger isochrones of age 1-80 Myr are also presented up to the main-sequence turn-off. Combining this set with that of Paper I for scaled-solar mixture isochrones, we provide a consistent set of isochrones that can be used to investigate populations of any value of α-enhancement. We confirm the earlier results of Paper I that inclusion of α-enhancement effects further reduces the age estimates of globular clusters by approximately 8% if [α/Fe]= +0.3. It is important to note the metallicity dependence of the change in age estimates (larger age reductions in lower metallicities). This reduces the age gap between the oldest metal-rich and metal-poor Galactic stellar populations and between the halo and the disk populations. We also investigate whether the effects of α-enhancement can be mimicked by increasing the total metal abundance in the manner proposed by Salaris and collaborators. We find such simple scaling formulae are valid at low metallicities but not at all at high metallicities near and above solar. Thus, it is essential to use the isochrones rigorously computed for α-enhancement when modeling metal-rich populations, such as bright galaxies. The isochrone tables, together with interpolation routines have been made available via internet.

Spectroscopic, Electrochemical, and Photochemical Studies of Self-Assembled via Axial Coordination Zinc Porphyrin−Fulleropyrrolidine Dyads†

Abstract: Spectroscopic, redox, and photochemical behavior of self-assembled donor−acceptor dyads formed by axial coordination of zinc tetraphenylporphyrin, (TPP)Zn, and fulleropyrrolidine bearing either pyridine or imidazole coordinating ligands were investigated. The UV−vis, 1H NMR, and ESI-mass spectral studies, as well as computational studies, revealed supramolecular 1:1 dyad formation between the electron donor [(TPP)Zn] and the electron acceptor, fulleropyrrolidine entities. The determined formation constant K values followed the order o-pyridyl ≪ m-pyridyl ≃ p-pyridyl ≪ N-phenyl imidazole entities of the fulleropyrrolidine. The evaluated thermodynamic parameters revealed stable complexation with complex dissociation enthalpies ranging between 26 and 32 kJ mol-1. The 1H NMR studies revealed axial coordination of the pyridine or imidazole ligands to the central zinc of (TPP)Zn, while the ESI-Mass spectral studies performed in CH2Cl2 matrix revealed the expected molecular ion peak of the self-assembled dyads. ...

Self-regulated Science Learning with Highly Gifted Students: the role of cognitive, motivational, epistemological, and environmental variables

Abstract: This research examines the issue of self-regulated learning among highly gifted elementary ( n = 93) and high school students ( n = 40) in science. Self-report measures assessed self-regulatory strategy use in science and a spectrum of environmental (perceived level of investigation) and individual prerequisites (motivational beliefs, goal orientation, epistemological beliefs and intentions). Firstly, high school students were experiencing less investigation in science, and test anxiety and work avoidance were more pronounced than with elementary students. Secondly, highly gifted girls' science-related motivational beliefs were less positive than those of boys. Thirdly, path analyses indicate that the level of investigation in the science learning environment strongly determines motivational and epistemological prerequisites of self-regulatory strategy use. The results indicate that exploration and discovery should be enabled and strengthened in science classrooms of highly gifted students.

Efficient generation and mapping of recessive developmental mutations using ENU mutagenesis.

Abstract: Treatment with N-ethyl-N-nitrosourea (ENU) efficiently generates single-nucleotide mutations in mice. Along with the renewed interest in this approach, much attention has been given recently to large screens with broad aims; however, more finely focused studies have proven very productive as well. Here we show how mutagenesis together with genetic mapping can facilitate the rapid characterization of recessive loci required for normal embryonic development. We screened third-generation progeny of mutagenized mice at embryonic day (E) 18.5 for abnormalities of organogenesis. We ascertained 15 monogenic mutations in the 54 families that were comprehensively analyzed. We carried out the experiment as an outcross, which facilitated the genetic mapping of the mutations by haplotype analysis. We mapped seven of the mutations and identified the affected locus in two lines. Using a hierarchical approach, it is possible to maximize the efficiency of this analysis so that it can be carried out easily with modest infrastructure and resources.

Detached-eddy simulation with compressibility corrections applied to a supersonic axisymmetric base flow

Abstract: Detached-eddy simulation is applied to an axisymmetric base flow at supersonic conditions. Detached-eddy simulation is a hybrid approach to modeling turbulence that combines the best features of the Reynolds-averaged Navier-Stokes and large-eddy simulation approaches. In the Reynolds-averaged mode, the model is currently based on either the Spalart-Allmaras turbulence model or Menter’s shear stress transport model; in the largeeddy simulation mode, it is based on the Smagorinski subgrid scale model. The intended application of detached-eddy simulation is the treatment of massively separated, highReynolds number flows over complex configurations (entire aircraft, automobiles, etc.). Because of the intented future application of the methods to complex configurations, Cobalt, an unstructured grid Navier-Stokes solver, is used. The current work incorporates compressible shear layer corrections in both the Spalart-Allmaras and shear stress transport-based detached-eddy simulation models. The effect of these corrections on both detached-eddy simulation and Reynolds-averaged Navier-Stokes models is examined, and comparisons are made to the experiments of Herrin and Dutton. Solutions are obtained on several grids—both structured and unstructured—to test the sensitivity of the models and code to grid refinement and grid type. The results show that predictions of base flows using detached-eddy simulation compare very well with available experimental data, including turbulence quantities in the wake of the axisymmetric body. @DOI: 10.1115/1.1517572#

Gas phase model of an ionic liquid: semi-empirical and ab initio bonding and molecular structure

Abstract: Semi-empirical (AM1 and PM3) and ab initio structures of the gas phase ion pair, bmim+(1-butyl-3-methyl imidazolium)–PF6−, have been calculated. The ab initio calculations include fully optimized structures at the RHF/3-21G(∗), RHF/6-31G∗, RHF/6-31G∗∗, MP2/6-31G∗, B3LYP/6-31G∗ and B3LYP/6-31G∗∗ levels. Semi-empirical structures (AM1 and PM3) are similar to those obtained from ab initio methods. The non-bonded interactions in these ion pairs are of the C–H⋯X type (C–H⋯F hydrogen bonds) and exist between F's on PF6− and (a) the imidazolium ring N–H, (b) the methyl group H adjacent to the ring and (c) H's on the butyl (bmim+) side chain. The ab initio ion pair structures contain hydrogen bonds that shorten with increasing basis set complexity. The movement of the bmim+ imidazolium ring C2–H along the proton transfer coordinate towards PF6− produces similar anharmonic functions for the RHF/6-31G∗//6-31G∗∗, MP2/6-31G∗//6-31G∗∗, RHF/6-31G∗∗/6-31+G(d,p)//6-31G∗∗, MP2/6-31G∗∗/6-31+G(d,p)//6-31G∗∗, B3LYP/6-31G∗//6-31G∗∗ and B3LYP/6-31G∗∗/6-31+G(d,p)//6-31G∗∗ levels. The existence of anharmonic functions that describe the proton transfer coordinate is consistent with the Del Bene model of hydrogen bonding.

Epistemological Beliefs and Thinking About Everyday Controversial Issues

Abstract: The authors investigated the relationship between individuals' beliefs about the nature of knowledge and the nature of learning (epistemological beliefs) and their thinking about everyday controversial issues. Adults (N = 174) ranging in age from 17 to 71 years old with a mean age of 38 completed the Schommer Epistemological Questionnaire (M. Schommer, 1990), which assessed their beliefs in the certainty and organization of knowledge and the speed and control of learning. After they had completed the questionnaire, they responded to a series of questions about two controversial issues that had been discussed in the local newspaper. Regression analyses indicated that the more the participants believed in complex and tentative knowledge, the more likely they were to take on multiple perspectives, be willing to modify their thinking, withhold ultimate decisions until all information was available, and acknowledge the complex, tentative nature of everyday issues. Epistemological beliefs that are heavily influenced by a higher level of education appear to relate to thinking beyond the classroom, and introducing controversial issues into the curriculum may reciprocally foster the development of epistemological beliefs.

Increased toxicity to invertebrates associated with a mixture of atrazine and organophosphate insecticides.

Abstract: This study examined the joint toxicity of atrazine and three organophosphate (OP) insecticides (chlorpyrifos, methyl parathion, and diazinon) exposed to Hyalella azteca and Musca domestica. A factorial design was used to evaluate the toxicity of binary mixtures in which the lethal concentration/lethal dose (LC1/LD1, LC5/LD5, LC15/LD15, and LC50/LD50) of each OP was combined with atrazine concentrations of 0, 10, 40, 80, and 200 microg/L for H. azteca and 0, 200, and 2,000 ng/mg for M. domestica. Atrazine concentrations (> or = 40 microg/L) in combination with each OP caused a significant increase in toxicity to H. azteca compared with the OPs dosed individually. Acetylcholinesterase (AChE) activity also was examined for the individual OPs with and without atrazine treatment. Atrazine in combination with each of the OPs resulted in a significant decrease in AChE activity compared with the OPs dosed individually. In addition, H. azteca that were pretreated with atrazine (> or = 40 microg/L) were much more sensitive to the OP insecticides compared with H. azteca that were not pretreated with atrazine before being tested. Topical exposure to atrazine concentrations did not significantly increase OP toxicity to M. domestica. The results of this study indicate the potential for increased toxicity in organisms exposed to environmental mixtures.

Studies on Covalently Linked Porphyrin−C60 Dyads: Stabilization of Charge-Separated States by Axial Coordination

Abstract: The effect of axial ligation on the photoinduced charge separation and charge recombination of a series of covalently linked porphyrin−C60 dyads is investigated Toward this, meso-tetraphenylporphyrin and its zinc(II) derivative are functionalized at the ortho or para positions of one of the aryl groups to bear a fulleropyrrolidine entity through a flexible ethylene dioxide bridge to probe the effect of intramolecular electron transfer phenomena In o-dichlorobenzene, 01 M (TBA)ClO4, the synthesized dyads exhibit seven one electron reversible redox reactions within in the potential window of the solvent and the measured redox potentials and UV−visible absorption spectra reveal charge−transfer interactions between the electron donor, porphyrin, and the electron acceptor, fullerene entities The geometric and electronic structures of the dyads probed by ab initio B3LYP/3-21G(*) methods also revealed the existence of charge−transfer interactions The excited state photochemical events are monitored by both

Designing online banner advertisements: should we animate?

Abstract: A common medium for advertising on the Internet is the use of banner ads. This study investigates recall and recognition of animated banner advertisements in an attempt to identify design guidelines. It was hypothesized that animation would increase recall and recognition of novel ads by increasing user awareness. No significant relationships were found between the use of animation and ability to recall and recognize banner ads. Results indicate that animation does not enhance user memory of online banner advertisements.

The Paradox of Priority

Abstract: The ubiquity of bank seniority is now a widely accepted fact in the academic literature. At the same time, trade creditors are sometimes granted a purchase money security interest in the materials or equipment they provide the firm. These two conflicting facts present a puzzle: Why would banks willingly give up a valuable priority claim on the firm, but only with respect to a subset of the firm's assets; We propose a resolution to this paradox of priority by arguing that trade creditors are better able to liquidate the materials they supply to a firm. When trade creditors have a security interest in these assets, their claims are state-contingent, and therefore dependent on the value of the assets pledged as collateral. Surprisingly, this ability of trade creditors to more efficiently liquidate the materials they supply to a firm also makes it desirable to subordinate the non-collateralized portion of their claims. Doing so increases the face value of a trade creditor's claim for a given level of borrowing, thereby increasing the "liquidation bang" from each trade credit buck. This combined priority structure maximizes social welfare by reducing the firm's overall cost of funding.

Spatio-Temporal Covariance Functions Generated by Mixtures

Abstract: Spatio-temporal covariance functions are introduced in this paper by using two approaches: (1) positive power mixture of purely spatial and purely temporal covariances, and (2) scale mixture of purely spatial and purely temporal covariances. Various parametric and nonparametric families of nonseparable spatio-temporal covariance functions are obtained with appropriate selections of the mixing function and covariances being mixed.

Electronic Interactions and Photoinduced Electron Transfer in Covalently Linked Porphyrin−C60(pyridine) Diads and Supramolecular Triads Formed by Self-Assembling the Diads and Zinc Porphyrin

Abstract: Supramolecular triads of the type (donor-1)−acceptor:(donor-2) composed of free-base porphyrin, fullerene, and zinc porphyrin, have been formed by a “covalent-coordinate” approach. Toward this, two diads, namely, 5-(3‘-(2‘ ‘-(3‘ ‘‘ or 4‘ ‘‘-pyridyl)fulleropyrrolidinyl-N)ethoxyphenyl)-10,15,20-triphenylporphyrin, bearing C60 as acceptor and free-base porphyrin, H2P, as donor were first synthesized. The diads and self-assembled supramolecular triads, which were formed by coordinating the pyridine group located on the diads to zinc tetraphenylporphyrin, ZnP, have been characterized by semiempirical PM3, electrochemistry, and steady-state and time-revolved spectroscopic techniques. Subpicosecond and nanosecond transient absorption spectral studies of diads revealed the occurrence of the electron transfer from the H2P moiety to the C60 entity via the excited singlet state of H2P. Clear evidence for the formation of triads in o-dichlorobenzene was obtained from the steady-state and time-resolved fluorescence me...

Density Functional Theory Calculations of Selected Ru(II) Two Ring Diimine Complex Dications

Abstract: Geometry optimization for a series of ten, two-ring diimine Ru(II) complexes was effected using the Gaussian 98 protocol at density functional theory (DFT) B3LYP level with basis sets 3-21G*and 3-21G**. HOMO-LUMO energy difference values compared favorably to the experimental data from electrochemistry [Delta E(1/2) = (E(1/2ox) - E(1/2red))] and the lowest energy absorption maxima, which for these complexes correspond to the metal-to-ligand charge transfer (MLCT) band. The HOMO and LUMO distributions from DFT support the idea that the lowest energy transitions are metal-to-ligand charge transfer and that the lowest energy LUMO for the mixed ligand complexes is located on 2,2'-bipyrazine (bpz), followed by 2,2'-bipyrimidine (bpm) and then 2,2'-bipyridine (bpy).

A Ferrocene-C60-Dinitrobenzene Triad: Synthesis and Computational, Electrochemical, and Photochemical Studies

Abstract: Synthesis and physicochemical characterization of a molecular triad comprised of ferrocene, C60, and dinitrobenzene entities is reported. Electrochemical studies revealed multiple redox processes involving all three redox active, ferrocene, C60, and dinitrobenzene entities. A total of eight reversible redox couples within the accessible potential window of o-dichlorobenzene containing 0.1 M (TBA)ClO4 are observed. A comparison between the measured redox potentials with those of the starting compounds revealed absence of any significant electronic interactions between the different redox entities. The geometric and electronic structure of the triad is elucidated by using ab initio B3LYP/3-21G(*) methods. In the energy optimized structure, as predicted by electrochemical studies, the first HOMO orbitals are found to be located on the ferrocene entity, whereas the first LUMO orbitals are mainly on the C60 entity with small orbital coefficients on the dinitrobenzene entity. The subsequent LUMO's track the obs...

Institutional Investors’ Preferences for REIT Stocks

Abstract: This article investigates the determinants of real estate investment trusts (REIT) portfolio investment and institutional REIT ownership using multivariate Tobit regressions. We contend that many institutional investors take larger positions in more liquid assets like REIT stocks, as compared with private real estate equities, because of liquidity considerations. Consistent with this contention, we find that liquidity constraints are significantly related to REIT portfolio investment by institutional investors. We also find that institutional investors have different preferences for REIT stocks than do other investors; they generally prefer larger, more liquid REIT stocks.

Efficient algorithms for minimizing tree pattern queries

Abstract: We consider the problem of minimizing tree pattern queries (TPQ) that arise in XML and in LDAP-style network directories. In [Minimization of Tree Pattern Queries, Proc. ACM SIGMOD Intl. Conf. Management of Data, 2001, pp. 497-508], Amer-Yahia, Cho, Lakshmanan and Srivastava presented an O(n4) algorithm for minimizing TPQs in the absence of integrity constraints (Case 1); n is the number of nodes in the query. Then they considered the problem of minimizing TPQs in the presence of three kinds of integrity constraints: required-child, required-descendant and subtype (Case 2). They presented an O(n6) algorithm for minimizing TPQs in the presence of only required-child and required-descendant constraints (i.e., no subtypes allowed; Case 3). We present O(n2), O(n4) and O(n2) algorithms for minimizing TPQs in these three cases, respectively, based on the concept of graph simulation. We believe that our O(n2) algorithms for Cases 1 and 3 are runtime optimal.

No, the Sky Is Not Falling: Evidence of Accounting Student Characteristics at FSA Schools, 1995–2000

Abstract: This article presents the most recent results of an ongoing, longitudinal study of characteristics of accounting students conducted by the Federation of Schools of Accountancy (FSA). Surveys were administered to seniors and Masteraˆ€™s students at FSA member schools in the United States in 1995 and again in 2000. Data regarding student characteristics in 1995 and 2000 are presented. Specifically, the study contains evidence pertaining to student quality, future educational plans, career plans, plans for professional certification, extracurricular involvement, attitude toward the 150‐hour requirement, and various demographic dimensions. The results of the survey do not coincide with those of other studies that have reported a decline in the quality of accounting students. On the contrary, our findings suggest that the quality of accounting students is not decreasing. Further research is necessary to more fully understand these contradictory findings and the direction and magnitude of any changes in student...

Remediation of heavy metal-contaminated soils using phosphorus: evaluation of bioavailability using an earthworm bioassay.

Abstract: This study investigated the effectiveness of phosphorus (P) as an in situ remediation technique in site soils collected from the Tri-State mining area. The site soils were treated with two different types (KH2PO4 and Super Triple Phosphate fertilizer) and levels (600 and 5,000 mg/kg) of phosphorus. A toxicokinetic approach was used to determine whether phosphorus amendments reduced heavy metal bioavailability to the earthworm Eisenia fetida. Bioaccumulation factors were used as a measure of bioavailability. Depuration patterns of lead, zinc, and cadmium also were studied after removing earthworms from contaminated soils and then placing them in noncontaminated artificial soil. Results showed that the high phosphorus treatments significantly reduced lead, zinc, and cadmium bioavailability to the earthworms, probably due to formation of metal-phosphate complexes in the soils. Results also indicated that other soil characteristics in addition to amended phosphorus have an affect on bioavailability. Depuration experiments showed a biphasic elimination pattern for each metal. The current results indicate that phosphorus soil amendments may reduce ecological risk to soil-inhabiting invertebrates exposed to heavy metal-contaminated soils.

A unified approach to form error evaluation

Abstract: Evaluation of form error is a critical aspect of many manufacturing processes. Machines such as the coordinate measuring machine (CMM) often employ the technique of the least squares form fitting algorithms. While based on sound mathematical principles, it is well known that the method of least squares often overestimates the tolerance zone, causing good parts to be rejected. Many methods have been proposed in efforts to improve upon results obtained via least squares, including those, which result in the minimum zone tolerance value. However, these methods are mathematically complex and often computationally slow for cases where a large number of data points are to be evaluated. Extensive amount of data is generated where measurement equipment such as laser scanners are used for inspection, as well as in reverse engineering applications. In this report, a unified linear approximation technique is introduced for use in evaluating the forms of straightness, flatness, circularity, and cylindricity. Non-linear equation for each form is linearized using Taylor expansion, then solved as a linear program using software written in C++ language. Examples are taken from the literature as well as from data collected on a coordinate measuring machine for comparison with least squares and minimum zone results. For all examples, the new formulations are found to equal or better than the least squares results and provide a good approximation to the minimum zone tolerance.