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Showing papers by "Texas Christian University published in 1997"


Journal ArticleDOI
TL;DR: In this article, the results of a comparative study of two networks of small-to medium-sized manufacturing enterprises in the U.S. wood products industry are presented. But they do not consider the effect of the number of participants in each network.
Abstract: This article presents the results of a comparative study of two networks of small- to medium-sized manufacturing enterprises in the U.S. wood products industry. Qualitative and survey data were collected from a sample of active participants in each network as well as from a sample of firms that were not network members (market firms) in the same industry. Using both qualitative and network analysis methodologies, we developed a model and testable propositions concerning key aspects of network structure and outcomes.

465 citations


Journal ArticleDOI
TL;DR: In this article, an integrative model representing treatment dynamics was tested for explaining long-term program retention, based on a multisite sample of 527 daily opioid users who remained in methadone maintenance a minimum of 3 months.

342 citations


Journal ArticleDOI
TL;DR: In this article, the authors found that patients staying in methadone treatment for a year or longer were nearly five times more likely to have better outcomes than those who did not stay in treatment.

317 citations


Journal ArticleDOI
TL;DR: Data suggest progesterone has antioxidant effects and support its potential as a treatment for brain injury, and compare brain levels of 8-isoprostaglandin F2 alpha, a marker of lipid peroxidation, after cortical contusion in male rats treated with either progester one or the oil vehicle.
Abstract: The gonadal hormone, progesterone, has been shown to have neuroprotective effects in injured nervous system, including the severity of postinjury cerebral edema. Progesterone’s attenuation of edema is accompanied by a sparing of neurons from secondary neuronal death and with improvements in cognitive outcome. In addition, we recently reported that postinjury blood-brain barrier (BBB) leakage, as measured by albumin immunostaining, was significantly lower in progesteronetreated than in nontreated rats, supporting a possible protective action of progesterone on the BBB. Because lipid membrane peroxidation is a major contributor to BBB breakdown, we hypothesized that progesterone limits this free radical-induced damage. An antioxidant action, neuroprotective in itself, would also account for progesterone’s effects on the BBB, edema, and cell survival after traumatic brain injury. To test progesterone’s possible antiperoxidation ef-fect, we compared brain levels of 8-isoprostaglandin F2α (8-isoPGF2α), a marker of lipid peroxidation, 24, 48, and 72 h after cortical contusion in male rats treated with either progesterone or the oil vehicle. The brains of progesteronetreated rats contained approximately one-third of the 8-isoPGF2α found in oil-treated rats. These data suggest progesterone has antioxidant effects and support its potential as a treatment for brain injury.

306 citations


Journal ArticleDOI
TL;DR: A meta-analysis of performance appraisal purpose research was conducted with 22 studies and a total sample size of 57,775 as discussed by the authors, showing that performance evaluations obtained for administrative purposes were, on average, one-third of a standard deviation larger than those obtained for research or employee development purposes.
Abstract: More than 40 years ago, Taylor and Wherry (1951) hypothesized that performance appraisal ratings obtained for administrative purposes, such as pay raises or promotions, would be more lenient than ratings obtained for research, feedback, or employee development purposes. However, research on appraisal purpose has yielded inconsistent results, with roughly half of such studies supporting this hypothesis and the other half refuting it. To account for those differences, a meta-analysis of performance appraisal purpose research was conducted with 22 studies and a total sample size of 57,775. Our results support Taylor and Wherry's hypothesis as performance evaluations obtained for administrative purposes were, on average, one-third of a standard deviation larger than those obtained for research or employee development purposes. In addition, moderator analyses indicated larger differences between ratings obtained for administrative and research purposes when performance evaluations were made in field settings, by practicing managers, and for real world subordinates. Implications for researchers and practitioners are discussed.

243 citations


Journal ArticleDOI
TL;DR: Evidence supporting the hypothesis that SROs produce an aversive emotional reaction with physiological and behavioral consequences is reviewed and common aspects of these phenomena are identified.
Abstract: A surprising reward omission (SRO) occurs when an appetitive reinforcer is not presented (or it is reduced in magnitude or quality) even though there are signals for its impending presentation. Evi...

183 citations


Journal ArticleDOI
TL;DR: Evidence is found for disruptive selection for host use, which is a critical assumption of sympatric speciation models, and high survival of F1, F2, and backcross hybrids on some plant genotypes in some years supported the host adaptation hypothesis.
Abstract: We studied the inheritance of survival ability in host-associated populations of the tephritid fly, Eurosta solidaginis, to test predictions of sympatric speciation models. Eurosta solidaginis induces galls on two species of goldenrod, Solidago altissima and S. gigantea. The host-associated populations have been hypothesized to be host races that originated in sympatry (Craig et al. 1993). We found evidence for disruptive selection for host use, which is a critical assumption of sympatric speciation models. Each host race had higher survival rates on their host plant than on the alternative host. F1 and backcross hybrids also had lower survival rates than the pure host-race flies on their host plant. Since assortative mating occurs due to host-plant preference (Craig et al. 1993) this would select for divergence in host preference. Low hybrid survival could have been due to strong genetic incompatibilities of the populations or due to host adaptation by each population. Strong genetic incompatibilities would result in poor survival on all host plants, while host adaptation could result in low overall survival with high hybrid survival on some host plants with particularly "benign" environments. High survival of F1 , F2 , and backcross hybrids on some plant genotypes in some years supported the host adaptation hypothesis. F1 flies mated and oviposited normally and produced viable F2 and backcross hybrids indicating gene flow is possible between the host races. A few flies developed and emerged on the alternative host plant. This demonstrates that genes necessary to utilize the alternative host exist in both host races. This could have facilitated the origin of one of the populations via a host shift from the ancestral host. The inheritance of survival ability appears to be an autosomal trait. We did not find evidence that survival ability was maternally influenced or sex linked.

125 citations


Journal ArticleDOI
TL;DR: A comprehensive prison-based treatment assessment (PTA) including studies of the In-prison Therapeutic Community (ITC) treatment process and posttreatment outcomes is conducted.
Abstract: In response to increasing problems associated with drug-abusing offenders, the 1991 Texas Legislature provided a statutory foundation for the development of a comprehensive drug treatment program within the state's criminal justice system. In an effort to assess the impact of the prison-based treatment component of this legislative mandate, the Texas Commission on Alcohol and Drug Abuse funded the Institute of Behavioral Research at Texas Christian University to conduct a comprehensive prison-based treatment assessment (PTA) including studies of the In-prison Therapeutic Community (ITC) treatment process and posttreatment outcomes. This article provides an overview of the research project and findings from the 6-month follow-up study. Preprison and during-treatment information was collected from 293 ITC program participants. Six-month follow-up interviews were completed with 222 ITC program graduates and compared with a comparison sample of 75 parolees who were eligible but not sent to ITC treatm...

113 citations


Journal ArticleDOI
TL;DR: In this paper, the influence of parent-child interactions on children's competence within several tasks was investigated, finding that parents were equally effective in their ability to scaffold their children's emerging skills.
Abstract: Building upon Wood & Middleton's (1975) concept of parental scaffolding, the influence of parent-child interactions on children's competence within several tasks was investigated. Thirty-two 2-year-old children visited our lab twice, once with their mothers and once with their fathers. During each session dyads participated in problem-solving and literacy tasks, followed by independent child performance tasks. Although subtle differences were found between mothers' and fathers' contingent behaviours displayed during the interactions, at a global level, parents were equally effective in their ability to scaffold their children's emerging skills. Specifically, parental scaffolding behaviours were associated with children's success measured both during the interaction and independently (i.e. following the interactions). These results have implications for the interpretation of research comparing mothers and fathers, and lend support to the claim that scaffolding can be an effective instructional strategy.

104 citations


Journal ArticleDOI
TL;DR: The Pictet-Spengler reaction of substrates with sufficiently large substituents, followed by treatment with acid, permits the 100% enantiospecific formation of trans-1,3-disubstituted- 1,2,3,4-tetrahydro-beta-carbolines for alkaloid total synthesis.
Abstract: The factors which effect the stereoselective formation of trans-1-alkyl-2-benzyl-3-(alkoxycarbonyl)-1,2,3,4-tetrahydro-β-carbolines and trans-3-(alkoxycarbonyl)-1-alkyl-2-(diphenylmethyl)-1,2,3,4-tetrahydro-β-carbolines by the Pictet−Spengler cyclization were examined by heating tryptophan derivatives with aldehydes of varied steric bulk under aprotic and acidic conditions, followed by determination of the ratio of cis to trans diastereomers so formed. The presence of a benzyl group at the Nb-nitrogen atom alters the diastereochemical outcome of this condensation to provide 100% trans stereoselectivity when the cyclization is carried out with cyclohexanecarboxaldehyde. Furthermore, when Nb-(diphenylmethyl)tryptophan isopropyl ester was condensed with aldehydes of any size, trans diastereomers are formed with 100% stereoselectively. The trans Nb-substituted diastereomers are thermodynamically more stable than their cis congeners as shown by equilibration experiments in TFA. Conversion of the cis diastereom...

94 citations



Journal ArticleDOI
TL;DR: In the second half of the 17th century, London's goldsmith-bankers formed a system of banking through mutual debt acceptance and interbanker clearing as mentioned in this paper, which created positive externalities for member bankers and promoted the use of bank supplied media of exchange during the Financial Revolution in England.

Journal ArticleDOI
TL;DR: In this paper, a survey with 232 small business respondents indicates that the payback method is still the preferred approach by 42.7 percent of the firms and the average minimal payback period averaged 2.81 years, a time period far shorter than the useful life of the asset and one that would indicate a required return far higher than most firms anticipate.
Abstract: In recent times, small business firms have created 80 percent of the new jobs in the United States. Thus, their methodology for capital investment decisions is very important, though it continues to be somewhat different from that used by larger business firms. A questionnaire survey with 232 small business respondents indicates that the payback method is still the preferred approach by 42.7 percent of the firms. Unlike many larger firms, their time horizon is often the period over which a financial institution will extend them funding. In any event, the “average” minimal payback period in the survey averaged 2.81 years, a time period far shorter than the useful life of the asset and one that would indicate a required return far higher than most firms anticipate. Somewhat encouraging was the increased use of discounted cash flow methods (27.6 percent), which is a higher rate of utilization than that indicated in other surveys of smaller firms over the last few decades.

Journal ArticleDOI
TL;DR: In this paper, the authors compile recent data regarding the timing and kinematics of tectonism for critical parts of southern Africa and East Gondwana, focusing on the period between ~ 650-500 Ma, and integrate these data into a regional framework.

Journal ArticleDOI
TL;DR: A structural equation model including client perceptions of their drug related problems, peer deviance, and family dysfunction as influences upon the formation of therapeutic relationships during treatment and rearrests following treatment showed therapeutic relationships were positively associated with recognition of drugrelated problems and negatively related to rearrest.
Abstract: Treatment efforts appear to be effective in reducing crime among drug using individuals, but components of the treatment process associated with client improvement need to be identified. Furthermore, these elements of treatment may play an intermediate role in the connection between client background characteristics and later criminal activity. The current study examines a structural equation model including client perceptions of their drug related problems, peer deviance, and family dysfunction as influences upon the formation of therapeutic relationships during treatment and rearrests following treatment. Results showed therapeutic relationships were positively associated with recognition of drug related problems and negatively related to rearrest. Peer deviance also was positively related to rearrest.

Book
09 Jan 1997
TL;DR: The sources for Islamic social Ideals: 1. Egalitarianism and the growth of a pious opposition 2. The Muslim reception of Greek ideas 3. The TAMING OF ISLAMIC EGALITARIANISM 4. The disassociation of egalitarianism and opposition 5. The didactic literature of the courts 6. Rationalisations of inequalities 7. Hierarchies of occupations Conclusion as discussed by the authors.
Abstract: Introduction Part I. Sources for Islamic Social Ideals: 1. Egalitarianism and the growth of a pious opposition 2. The Muslim reception of Greek ideas 3. The Muslim reception of Iranian social models Part II. THE TAMING OF ISLAMIC EGALITARIANISM: 4. The disassociation of egalitarianism and opposition 5. The didactic literature of the courts 6. Rationalisations of inequalities 7. Hierarchies of occupations Conclusion.

Journal ArticleDOI
TL;DR: In this article, the authors examined the role of a number of organizational variables including met expectations, role conflict, role ambiguity, job satisfaction, organization commitment and intention to leave and their relationships to job stress.
Abstract: As productivity pressures, job uncertainties, changing sales strategies, and growing international competition increase, the salesperson experiences unprecedented levels of job stress. Cause and effect of job stress still remains poorly understood. Examines the role of a number of organizational variables including met expectations, role conflict, role ambiguity, job satisfaction, organization commitment and intention to leave and their relationships to job stress. The sample is drawn from an international, service‐oriented salesforce of a large Fortune 500 organization. Provides strong support for the hypothesized model relationship. Presents a discussion and implications of the results along with a summary of needed future research.

Journal ArticleDOI
TL;DR: In this article, the cyclic C6 cluster was identified for the first time in Fourier transform infrared spectra of the products from the laser evaporation of graphite rods trapped in Ar at ∼10 K.
Abstract: The cyclic C6 cluster has been identified for the first time in Fourier transform infrared spectra of the products from the laser evaporation of graphite rods trapped in Ar at ∼10 K. Measurements on spectra produced using both 12C- and 13C-enriched rods combined with the results of new density functional theory calculations performed in the present work as well as previous calculations by Martin and Taylor, have resulted in the assignment of the most intense infrared active mode, ν4(e′)=1694.9 cm−1 of the cyclic C6 isomer with D3h symmetry. This assignment is based on excellent agreement of the frequency, 13C isotopic shifts, and relative intensities with the theoretical predictions.

Journal ArticleDOI
TL;DR: In this article, the relationship between topographic features and the relative abundances of vegetation types was analyzed for the mid-montane conifer forests, the upper montane conifers, and the alpine areas of Lassen Volcanic National Park in the Cascade Range of northern California using Landsat Thematic Mapper data.
Abstract: The relationships between topographic features and the relative abundances of vegetation types were analyzed for the mid-montane conifer forests, the upper montane conifer forests and the alpine areas of Lassen Volcanic National Park in the Cascade Range of northern California using Landsat Thematic Mapper data. Vegetation types were identified from Landsat Thematic Mapper data and included pine, fir, montane chaparral, willow/alder and herbaceous communities. Topographic features including aspect, slope steepness, slope configuration (i.e., convex, straight or concave) and slope position (i.e., ridge top to valley bottom) were computed from USGS Digital Elevation Models. The distribution of montane chaparral was consistent with its dependency on fire with chaparral communities being more abundant on more xeric aspects and on steeper and more xeric slope configurations. Slope position was important in determining the distribution of willow/alder communities which were more abundant in valley bottom locations. Both slope steepness and slope position affected the abundance of herbaceous communities. Herbaceous communities were: (1) more prevalent on steeper slopes due to the distribution of dicotyledonous forb species; and (2) more abundant in valley bottoms due to the distribution of monocotyledonous species in wet meadows. Pines and firs were separated along a gradient of slope steepness with the firs being more abundant on steep slopes and the pines being more abundant on shallow slopes. In the alpine areas above 2350 m, the abundance of most vegetation types declined with increasingly mesic aspects. This decline may be related to the prolonged persistence of snow in areas of less intense solar radiation.

Journal ArticleDOI
TL;DR: Drug abuse counseling was enhanced by node-link mapping, a visual representation technique, and evaluated in a posttreatment follow-up study, finding that among clients staying less than 6 months in treatment, those in the mapping group had fewer urine samples that tested positive for opiates at follow- up.
Abstract: Drug abuse counseling was enhanced by node-link mapping, a visual representation technique, and evaluated in a posttreatment follow-up study. Clients randomly assigned to receive mapping counseling reported less criminal activity 12 months after treatment than did clients in the standard counseling condition. It was also found that among clients staying less than 6 months in treatment, those in the mapping group had fewer urine samples that tested positive for opiates at follow-up. Thus, mapping-enhanced counseling may be especially beneficial for clients who leave treatment prematurely.

Journal ArticleDOI
TL;DR: Findings support broader use of MM in helping reduce HIV risks among injection drug users and highlight the need to explore ways to encourage treatment compliance in order to reduce risky practices.

Journal ArticleDOI
TL;DR: This paper applied H. J. Eysenck's (1967) theoretical perspective on the development of anxiety to explain audience perceptions of public speakers and found that the effects of social conditioning, particularly punishment, and the relative conditionability of an individual's nervous system combine to predict behavioral responses to state anxiety.
Abstract: This study applies H. J. Eysenck's (1967) theoretical perspective on the development of anxiety to explain audience perceptions of public speakers. Specifically, the effects of social conditioning, particularly punishment, and the relative conditionability of an individual's nervous system combine to predict behavioral responses to state anxiety. Speakers presented five‐minute speeches under normal classroom conditions, were videotaped, and speaker anxiety behaviors and audience‐observed speaker anxiety were assessed by teams of raters. The hypothesis that behavioral rigidity and inhibition are significant, additive predictors of audience perceived speaker state anxiety was confirmed. The authors discuss these findings in light of treatment strategies, such as flooding and systematic desensitization, designed to counteract behavioral inhibition.

Journal ArticleDOI
TL;DR: In this paper, a 70-item electronic mail survey measured five categories of variables: personal attributes, environmental characteristics, perceived media characteristics, usage, and outcomes, and found that social integration with a community of users contributed to the prediction of each type of outcome.
Abstract: This study was designed to identify factors that best predicted the amount and perceived benefits of network use. A 70-item electronic mail survey measured five categories of variables: personal attributes, environmental characteristics, perceived media characteristics, usage, and outcomes. It was returned by 66% of a random sample of 300 network users. Respondents were active network users with high levels of teaching tenure, schooling, and computer experience, and convenient access to equipment needed to use the Internet. Outcomes reported for network use mainly centered around professional development activities, whereas personal and instructional outcomes were less frequently reported. Multiple regression equations predicted 28% of amount of use, 46% of variety of uses, 45% of professional benefits, 16% of personal gratifications, and 25% of instructional outcomes. Socially oriented factors appeared repeatedly in these equations. Social integration with a community of users entered all but one of the equations, social presence contributed to the prediction of each type of outcome, and number of contacts regularly reached via the network was associated with both amount and variety of use. These findings suggested that network facilitators should implement strategies to increase interactions among potential and current network users and to enhance perceptions of the systems' social presence.

Journal ArticleDOI
TL;DR: Samples of porous sol-gel glass, after being stabilized at 750°C, were impregnated with progesterone, estradiol, estrone, and hydrocortisone, and diffusion coefficients for those steroids inside the pores filled with pure ethanol, ethanol-water mixture or physiological solution were determined as mentioned in this paper.
Abstract: Samples of porous sol-gel glass, after being stabilized at 750°C, were impregnated with progesterone, estradiol, estrone, and hydrocortisone. Diffusion coefficients for those steroids inside the pores filled with pure ethanol, ethanol-water mixture or physiological solution were determined. It is shown that permeability is favored for steroids having fewer hydroxyl and carbonyl groups. Solvents that readily dissolve steroids increase the diffusion rate and thus the amount of delivered material. The flow of steroids in small pores is less restricted than in larger pores.

Journal ArticleDOI
TL;DR: The potential contributions GIS could make to urban economic and real estate economic research and open debate on GIS as applied to these fields are discussed.

Proceedings ArticleDOI
08 Oct 1997
TL;DR: A miniature gas chromatography (GC) system has been designed and fabricated using silicon micromachining and integrated circuit (IC) processing techniques to separate binary gas mixtures composed of ammonia and nitrogen dioxide when isothermally operated.
Abstract: A miniature gas chromatography (GC) system has been designed and fabricated using silicon micromachining and integrated circuit (IC) processing techniques. The silicon micromachined gas chromatography system (SMGCS) is composed of a miniature sample injector that incorporates a 10 /spl mu/l sample loop; a 0.9-m long, rectangular-shaped (300 /spl mu/m width and 10 /spl mu/m height) capillary column coated with a 0.2-/spl mu/m thick copper phthalocyanine (CuPc) stationary-phase; and a dual-detector scheme based upon a CuPc-coated chemiresistor and a commercially available, 125-/spl mu/m diameter thermal conductivity detector (TCD) bead. Silicon micromachining was employed to fabricate the interface between the sample injector and the GC column, the column itself, and the dual-detector cavity. A novel IC thin-film processing technique was developed to sublime the CuPc stationary-phase coating on the column walls that were micromachined in the host silicon wafer substrate and Pyrex cover plate, which were then electrostatically bonded together. The SMGCS can separate binary gas mixtures composed of parts per-million (ppm) concentrations of ammonia (NH/sub 3/) and nitrogen dioxide (NO/sub 2/) when isothermally operated (55-80/spl deg/C). With a helium carrier gas and nitrogen diluent, a 10 /spl mu/l sample volume containing ammonia and nitrogen dioxide injected at 40 psi (2.8/spl times/10/sup 5/ Pa) can be separated in less than 30 minutes.

Journal ArticleDOI
TL;DR: According to Gordon Allport's contact hypothesis, positive contact with a member of a negatively stereotyped group might ameliorate negative attitudes not only toward the specific member but also toward the group as a whole as discussed by the authors.
Abstract: According to Gordon Allport's contact hypothesis, positive contact with a member of a negatively stereotyped group might ameliorate negative attitudes not only toward the specific member but also toward the group as a whole (generalization). In a direct empirical test of theoretical suggestions that individuating information might decrease the generalization part of the contact hypothesis, students learned material cooperatively with a "homosexual" confederate. To illustrate the material, the confederate used either impersonal or personal analogies. Students in the two conditions liked the confederate equally, but students who received personal analogies were less likely to ameliorate their attitudes toward homosexuals. The discussion addresses factors that might reduce the cognitive association between a group member and his or her group.

Journal ArticleDOI
TL;DR: In this paper, an ecological water treatment system consisting of periphyton and fish is proposed to remove polluted water using an ecological peripathyroid and fish, which can be harvested as nutrient sinks.
Abstract: We propose that phosphorus and nitrogen can be removed from polluted water using an ecological water treatment system consisting of periphyton and fish. In the proposed system, polluted water flows through a series of vessels, and the nutrients are taken up by periphyton growing on porous screens. Algal-grazing fish feed on the periphyton and either assimilate or egest the nutrients in mucus-bound feces that settle from the water into a sediment trap. Both the fish and their feces can be harvested as nutrient sinks. In this study we examined the effects of an algal-grazing cichlid (Tilapia mossambica) and a stoneroller minnow (Campostoma anomalum) on nutrient removal by the proposed water treatment system. In two experiments using tank-mesocosms, we found that the algal- grazing fish consumed the periphyton and transferred nutrients into the fish's body tissues or the sediments. The mass of phosphorus sequestered in the nutrient sink in the body tissues of the fish was approximately equivalent to the phosphorus sink in the sediments. High removal rates for phosphorus and nitrogen suggest that the proposed ecological water treatment system may be an effective ecotechnology for removal of nutrients from polluted water.

Journal ArticleDOI
TL;DR: Results emphasized the value in differentiating between these types of drinking clients, and it is suggested that failure to do so may account for earlier contradictory results about the role alcohol consumption has in treatment outcomes for methadone-maintenance clients.