Showing papers by "Texas A&M University published in 1996"

The behavioral consequences of service quality

Abstract: If service quality relates to retention of customers at the aggregate level, as other research has indicated, then evidence of its impact on customers’ behavioral responses should be detectable. Th...

Mechanics of Laminated Composite Plates and Shells : Theory and Analysis, Second Edition

Abstract: The use of composite materials in engineering structures continues to increase dramatically, and there have been equally significant advances in modeling for general and composite materials and structures in particular. To reflect these developments, renowned author, educator, and researcher J.N. Reddy created an enhanced second edit

The robustness of test statistics to nonnormality and specification error in confirmatory factor analysis.

Abstract: Monte Carlo computer simulations were used to investigate the performance of three X 2 test statistics in confirmatory factor analysis (CFA). Normal theory maximum likelihood )~2 (ML), Browne's asymptotic distribution free X 2 (ADF), and the Satorra-Bentler rescaled X 2 (SB) were examined under varying conditions of sample size, model specification, and multivariate distribution. For properly specified models, ML and SB showed no evidence of bias under normal distributions across all sample sizes, whereas ADF was biased at all but the largest sample sizes. ML was increasingly overestimated with increasing nonnormality, but both SB (at all sample sizes) and ADF (only at large sample sizes) showed no evidence of bias. For misspecified models, ML was again inflated with increasing nonnormality, but both SB and ADF were underestimated with increasing nonnormality. It appears that the power of the SB and ADF test statistics to detect a model misspecification is attenuated given nonnormally distributed data.

Lying in everyday life.

Abstract: In 2 diary studies of lying, 77 college students reported telling 2 lies a day, and 70 community members told 1. Participants told more self-centered lies than other-oriented lies, except in dyads involving only women, in which other-oriented lies were as common as self-centered ones. Participants told relatively more self-centered lies to men and relatively more other-oriented lies to women. Consistent with the view of lying as an everyday social interaction process, participants said that they did not regard their lies as serious and did not plan them much or worry about being caught. Still, social interactions in which lies were told were less pleasant and less intimate than those in which no lies were told.

Development and evaluation of sediment quality guidelines for Florida coastal waters.

Abstract: The weight-of-evidence approach to the development of sediment quality guidelines (SQGs) was modified to support the derivation of biological effects-based SQGs for Florida coastal waters. Numerical SQGs were derived for 34 substances, including nine trace metals, 13 individual polycyclic aromatic hydrocarbons (PAHs), three groups of PAHs, total polychlorinated biphenyls (PCBs), seven pesticides and one phthalate ester. For each substance, a threshold effects level (TEL) and a probable effects level (PEL) was calculated. These two values defined three ranges of chemical concentrations, including those that were (1) rarely, (2) occasionally or (3) frequently associated with adverse effects. The SQGs were then evaluated to determine their degree of agreement with other guidelines (an indicator of comparability) and the percent incidence of adverse effects within each concentration range (an indicator of reliability). The guidelines also were used to classify (using a dichotomous system: toxic, with one or more exceedances of the PELs or non-toxic, with no exceedances of the TELs) sediment samples collected from various locations in Florida and the Gulf of Mexico. The accuracy of these predictions was then evaluated using the results of the biological tests that were performed on the same sediment samples. The resultant SQGs were demonstrated to provide practical, reliable and predictive tools for assessing sediment quality in Florida and elsewhere in the southeastern portion of the United States.

The Market for Corporate Control and Firm Innovation

Abstract: This research examines an integrated theoretical model that explains how strategies for participating in the market for corporate control (acquisitions and divestitures) affect internal control mec...

Carbonate and Gypsum

Abstract: Inorganic carbonate in soil occurs predominantly as the sparingly soluble alkaline-earth carbonates, calcite (CaCOs) and dolomite (CaMg(CO,),). Calcite is usually the dominant form in active pedogenic environments (Doner & Lynn, 1977; Nelson, 1982). There are only a few reported occurrences of aragonite (CaCOs) and vaterite (CaCOs) in soils. Sodium carbonate and magnesium carbonate and hydroxycarbonate are common in evaporates or in regions of high-salt deposition in soil. Concentration of dissolved carbonate is controlled by equilibrium relations of the solid-phase carbonates and gas-phase CO*. Concentration of dissolved carbonate is likely to be higher in systems with high partial pressures of C02, e.g., in flooded soils or in microenvironments of high microbial activity, or in sodic soils, because of the high solubility of Na&Os. Also, calcite and dolomite usually control the activities of Ca2+(aq) and Mg2+(aq) in soils containing these minerals. Calcium carbonate contents of carbonate-influenced soils range from traces to greater than 80%. Calcite exists in a variety of forms, from nodules of 1 cm or greater diameter to submicrometer particles to well-formed rhomboids. The presence of carbonates is usually associated with neutral to alkaline soils, but solid-

Conflict in close relationships: an attachment perspective.

Abstract: This study investigated how perceptions of current dating partners and relationships change after people with different attachment orientations attempt to resolve a problem in their relationship. Dating couples were videotaped while they tried to resolve either a major or a minor problem. Confirming predictions from attachment theory, men and women who had a more ambivalent orientation perceived their partner and relationship in relatively less positive terms after discussing a major problem. Observer ratings revealed that more ambivalent women who tried to resolve a major problem displayed particularly strong stress and anxiety and engaged in more negative behaviors. Conversely, men with a more avoidant orientation were rated as less warm and supportive, especially if they discussed a major problem. These results are discussed in terms of how highly ambivalent and highly avoidant people differentially perceive and respond to distressing events.

Altruism in Anonymous Dictator Games

Abstract: We conduct double-anonymous dictator experiments to explore the role of altruism in motivating subjects’ behavior. We vary the extent to which an anonymous recipient is deserving of aid and investigate its effect on the allocation of a fixed pie by student subjects. This is accomplished by including as treatments: (1) an anonymous student subject and (2) an established charity. We find that a significant increase in donations occurs when we increase the extent to which a donation goes to a recipient generally agreed to be “deserving.” We conclude that subjects are rational in the way they incorporate fairness into their decisions.

The fate of nitrogen and phosphorus at the land-sea margin of the North Atlantic Ocean

Abstract: Five large rivers that discharge on the western North Atlantic continental shelf carry about 45% of the nitrogen (N) and 70% of the phosphorus (P) that others estimate to be the total flux of these elements from the entire North Atlantic watershed, including North, Central and South America, Europe, and Northwest Africa. We estimate that 61 · 109 moles y-1 of N and 20 · 109 moles y-1 of P from the large rivers are buried with sediments in their deltas, and that an equal amount of N and P from the large rivers is lost to the shelf through burial of river sediments that are deposited directly on the continental slope. The effective transport of active N and P from land to the shelf through the very large rivers is thus reduced to 292 · 109 moles y-1 of N and 13 · 109 moles y-1 of P.

Composition and size of type I, IIA, IID/X, and IIB fibers and citrate synthase activity of rat muscle

Abstract: A population of muscle fibers containing a myosin heavy-chain isoform IId (or 2x) has recently been identified in rat muscle. The purpose of this study was to histochemically determine the relative population and size of muscle fibers composed of type IID/X fibers as well as type I, IIA, and IIB fibers to estimate the absolute mass of the different types of fibers in rat muscle. In addition, muscle citrate synthase activity was measured to determine the relationship between fiber composition and muscle oxidative capacity. Seventy-six muscles or muscle parts from the face, neck, shoulder, arm, trunk, hip, thigh, and leg of three adult (4.5-5 mo of age) male Sprague-Dawley rats were removed, weighed, and frozen for histochemical and biochemical analyses. The data demonstrated that type IIB fibers make up 71% of the total muscle mass, type IID/X fibers 18%, type IIA fibers 5%, and type I fibers 6%. The mean cross-sectional area across all muscles was 5,078 +/- 175 microns 2 for type IIB fibers, 3,078 +/- 105 microns2 for type IID/X fibers, 2,045 +/- 80 microns2 for type IIA fibers, and 1,898 +/- 90 microns2 for type I fibers. Citrate synthase activity, an indicator of muscle mitochondrial content, was most closely related to the population of type IIA fibers and was in the rank order of type IIA > I > IID/X > IIB. NADH-tetrazolium reductase staining intensity also confirmed this order. These data demonstrate that type IID/X fibers make up a significant portion of the adult rat muscle mass and are intermediate to type IIA and IIB fibers in regard to fiber size and oxidative potential.

Forces contributing to the conformational stability of proteins

Abstract: For 35 years, the prevailing view has been that the hydrophobic effect is the dominant force in protein folding. The importance of hydrogen bonding was always clear, but whether it made a net favorable contribution to protein stability was not. Studies of mutant proteins have improved our understanding of the forces stabilizing proteins. They suggest that hydrogen bonding and the hydrophobic effect make large but comparable contributions to the stability of globular proteins.

Fault-tolerant computer system design

Abstract: In the ten years since the publication of the first edition of this book, the field of fault-tolerant design has broadened in appeal, particularly with its emerging application in distributed computing. This new edition specifically deals with this dynamically changing computing environment, incorporating new topics such as fault-tolerance in multiprocessor and distributed systems.

Cell-to-Cell and Long-Distance Transport of Viruses in Plants.

Abstract: The idea that viruses move through plants in two distinct modes was accurately concluded by G. Samuel in a 1934 paper describing the transport of tobacco mosaic virus (TMV) through solanaceous hosts: “lt is considered that these facts favour the theory of a slow cell to cell movement of the virus via the plasmodesmen, combined with a rapid distribution through the plant via the phloem” (Samuel, 1934). It is now firmly established that plant viruses move from cell to cell and over long distances by exploiting and modifying preexisting pathways for macromolecular movement within cells, between cells, and between organs. In this review, we focus on the roles of vira1 and host components in the movement of viruses through these pathways. Exhaustive coverage of all aspects of movement is not possible, but the reader is referred to several excellent reviews that emphasize various facets of shortand long-range virus transport (Atabekov and Taliansky, 1990; Maule, 1991; Deom et al., 1992; Citovsky, 1993; Leisner and Turgeon, 1993; Lucas and Gilbertson, 1994; Lucas, 1995).

An implicit time-stepping scheme for rigid body dynamics with inelastic collisions and coulomb friction

Abstract: In this paper a new time-stepping method for simulating systems of rigid bodies is given which incorporates Coulomb friction and inelastic impacts and shocks. Unlike other methods which take an instantaneous point of view, this method does not need to identify explicitly impulsive forces. Instead, the treatment is similar to that of J. J. Moreau and Monteiro-Marques, except that the numerical formulation used here ensures that there is no inter-penetration of rigid bodies, unlike their velocity-based formulation. Numerical results are given for the method presented here for a spinning rod impacting a table in two dimensions, and a system of four balls colliding on a table in a fully three-dimensional way. These numerical results also show the practicality of the method, and convergence of the method as the step size becomes small.

Perceiving interpersonal conflict and reacting to it: the case for agreeableness.

Abstract: Two converging, multimethod studies probed the hypothesis that individual differences in Agreeableness are related to patterns of interpersonal conflict. In Study 1, participants (N = 263) evaluated the efficacy of 11 modes of conflict resolution within the context of 5 different interpersonal relationships. Across all relationships, high- and low-agreeable participants rated negotiation and disengagement tactics as better choices that power assertion tactics. However, low-agreeable participants rated power assertion as a better choice than did high-agreeable participants. In Study 2, participants (N = 124) were assigned partners and were asked to resolve jointly 2 social conflict problems. Partners were videotaped, and observers coded behaviors. Participants also completed ratings of perceived conflict, partner perception, and liking of their partner. Agreeableness differences, sex of participant, and type of dyad partner were related to patterns of interpersonal conflict. Results were discussed in terms of personality and social influences during interpersonal conflict.

Expression of Norwalk virus capsid protein in transgenic tobacco and potato and its oral immunogenicity in mice.

Abstract: Alternatives to cell culture systems for production of recombinant proteins could make very safe vaccines at a lower cost. We have used genetically engineered plants for expression of candidate vaccine antigens with the goal of using the edible plant organs for economical delivery of oral vaccines. Transgenic tobacco and potato plants were created that express the capsid protein of Norwalk virus, a calicivirus that causes epidemic acute gastroenteritis in humans. The capsid protein could be extracted from tobacco leaves in the form of 38-nm Norwalk virus-like particles. Recombinant Norwalk virus-like particle (rNV) was previously recovered when the same gene was expressed in recombinant baculovirus-infected insect cells. The capsid protein expressed in tobacco leaves and potato tubers cosedimented in sucrose gradients with insect cell-derived rNV and appeared identical to insect cell-derived rNV on immunoblots of SDS/polyacrylamide gels. The plant-expressed rNV was orally immunogenic in mice. Extracts of tobacco leaf expressing rNV were given to CD1 mice by gavage, and the treated mice developed both serum IgG and secretory IgA specific for rNV. Furthermore, when potato tubers expressing rNV were fed directly to mice, they developed serum IgG specific for rNV. These results indicate the potential usefulness of plants for production and delivery of edible vaccines. This is an appropriate technology for developing countries where vaccines are urgently needed.

The Acid-Mediated Denaturation Pathway of Transthyretin Yields a Conformational Intermediate That Can Self-Assemble into Amyloid†

Abstract: Transthyretin (TTR) amyloid fibril formation is observed during partial acid denaturation and while refolding acid-denatured TTR, implying that amyloid fibril formation results from the self-assembly of a conformational intermediate. The acid denaturation pathway of TTR has been studied in detail herein employing a variety of biophysical methods to characterize the intermediate(s) capable of amyloid fibril formation. At physiological concentrations, tetrameric TTR remains associated from pH 7 to pH 5 and is incapable of amyloid fibril formation. Tetrameric TTR dissociates to a monomer in a process that is dependent on both pH and protein concentration below pH 5. The extent of amyloid fibril formation correlates with the concentration of the TTR monomer having an altered, but defined, tertiary structure over the pH range of 5.0−3.9. The inherent Trp fluorescence-monitored denaturation curve of TTR exhibits a plateau over the pH range where amyloid fibril formation is observed (albeit at a higher concentra...

Micro-local approach to the Hadamard condition in quantum field theory on curved space-time

Abstract: For the two-point distribution of a quasi-free Klein-Gordon neutral scalar quantum field on an arbitrary four dimensional globally hyperbolic curved space-time we prove the equivalence of (1) the global Hadamard condition, (2) the property that the Feynman propagator is a distinguished parametrix in the sense of Duistermaat and Hormander, and (3) a new property referred to as the wave front set spectral condition (WFSSC), because it is reminiscent of the spectral condition in axiomatic quantum field theory on Minkowski space. Results in micro-local analysis such as the propagation of singularities theorem and the uniqueness up toC∞ of distinguished parametrices are employed in the proof. We include a review of Kay and Wald's rigorous definition of the global Hadamard condition and the theory of distinguished parametrices, specializing to the case of the Klein-Gordon operator on a globally hyperbolic space-time. As an alternative to a recent computation of the wave front set of a globally Hadamard two-point distribution on a globally hyperbolic curved space-time, given elsewhere by Kohler (to correct an incomplete computation in [32]), we present a version of this computation that does not use a deformation argument such as that used in Fulling, Narcowich and Wald and is independent of the Cauchy evolution argument of Fulling, Sweeny and Wald (both of which are relied upon in Kohler's proof). This leads to a simple micro-local proof of the preservation of Hadamard form under Cauchy evolution (first shown by Fulling, Sweeny and Wald) relying only on the propagation of singularities theorem. In another paper [33], the equivalence theorem is used to prove a conjecture by Kay that a locally Hadamard quasi-free Klein-Gordon state on any globally hyperbolic curved space-time must be globally Hadamard.

Organization-motivated aggression: a research framework

Abstract: Aggression and violence are of increasing concern to American employees and employers; however, these issues have received limited research attention in the management literature. We focus here on those aggressive actions and violent outcomes that are instigated by factors in the organization itself, labeled organization-motivated aggression (OMA) and organization-motivated violence (OMV). Specifically, we define the terms OMA and OMV, provide a social learning model of OMA, and present research propositions related to the model.

Twenty-five coregulated transcripts define a sterigmatocystin gene cluster in Aspergillus nidulans.

Abstract: Sterigmatocystin (ST) and the aflatoxins (AFs), related fungal secondary metabolites, are among the most toxic, mutagenic, and carcinogenic natural products known. The ST biosynthetic pathway in Aspergillus nidulans is estimated to involve at least 15 enzymatic activities, while certain Aspergillus parasiticus, Aspergillus flavus, and Aspergillus nomius strains contain additional activities that convert ST to AF. We have characterized a 60-kb region in the A. nidulans genome and find it contains many, if not all, of the genes needed for ST biosynthesis. This region includes verA, a structural gene previously shown to be required for ST biosynthesis, and 24 additional closely spaced transcripts ranging in size from 0.6 to 7.2 kb that are coordinately induced only under ST-producing conditions. Each end of this gene cluster is demarcated by transcripts that are expressed under both ST-inducing and non-ST-inducing conditions. Deduced polypeptide sequences of regions within this cluster had a high percentage of identity with enzymes that have activities predicted for ST/AF biosynthesis, including a polyketide synthase, a fatty acid synthase (alpha and beta subunits), five monooxygenases, four dehydrogenases, an esterase, an 0-methyltransferase, a reductase, an oxidase, and a zinc cluster DNA binding protein. A revised system for naming the genes of the ST pathway is presented.

Enhancing helping behavior: An integrative framework for promotion planning

Abstract: Charitable organizations play a vital role in our society, as is evidenced by their enormous economic and social impact. Yet, for many of them, soliciting adequate resources to carry out their mand...