Showing papers by "University of North Texas published in 2003"

Minimum Lagrange Multiplier Unit Root Test with Two Structural Breaks

Abstract: The endogenous two-break unit root test of Lumsdaine and Papell is derived assuming no structural breaks under the null. Thus, rejection of the null does not necessarily imply rejection of a unit root per se, but may imply rejection of a unit root without break. Similarly, the alternative does not necessarily imply trend stationarity with breaks, but may indicate a unit root with breaks. In this paper, we propose an endogenous two-break Lagrange multiplier unit root test that allows for breaks under both the null and alternative hypotheses. As a result, rejection of the null unambiguously implies trend stationarity.

Elements of resilience after the World Trade Center disaster: reconstituting New York City's Emergency Operations Centre.

Abstract: In this paper we examine the reconstitution of the Emergency Operations Centre (EOC) after its destruction in the World Trade Center attack, using that event to highlight several features of resilience. The paper summarises basic EOC functions, and then presents conceptions of resilience as understood from several disciplinary perspectives, noting that work in these fields has sought to understand how a natural or social system that experiences disturbance sustains its functional processes. We observe that, although the physical EOC facility was destroyed, the organisation that had been established to manage crises in New York City continued, enabling a response that drew on the resources of New York City and neighbouring communities, states and the federal government. Availability of resources — which substituted for redundancy of personnel, equipment and space — pre-existing relationships that eased communication challenges as the emergency developed and the continuation of organisational patterns of response integration and role assignments were among the factors that contributed to resilience following the attack.

Emergent phenomena and the sociology of disaster: lessons, trends and opportunities from the research literature

Abstract: Research on emergent behavior has been a significant topic within disaster studies Through a detailed review of the literature we provide background information about this particular branch of disaster sociology Following a brief discussion of the process by which literature was selected, important trends and areas of debate are discussed These include the validation of previous findings, an expansion of the discussion on emergent phenomena and a critique of the bureaucratic approach We conclude with implications for the theory and practice of emergency management

Transactors, Transformers and Beyond. A Multi-Method Development of a Theoretical Typology of Leadership.

Abstract: Extends the transactional‐transformational model of leadership by deductively developing four theoretical behavioral types of leadership based on a historical analysis of leadership literature. Then, in an exploratory empirical phase, uses two data sets to inductively develop alternative models of leadership types. Finally, with a third data set, tests several theoretically plausible typologies using second‐order confirmatory factor analysis (CFA). The results of the CFA generally support the existence of four leadership types: directive leadership, transactional leadership, transformational leadership, and empowering leadership.

Are CO2 Emission Levels Converging Among Industrial Countries

Abstract: Time paths of carbon dioxide emissions intwenty-one industrial countries are examinedfrom 1960–1997 to test for stochastic andconditional convergence. Both panel unit roottests and cross-section regressions areperformed. Overall, we find significantevidence that CO2 emissions haveconverged.

Sometimes You Just Have to Leave: Domestic Threats and Forced Migration, 1964-1989

Abstract: In this study we explore why persons flee their homes to become refugees and internally displaced persons. We contend that individuals will tend to flee when the integrity of their person is threat...

Cause related marketing: how generation y responds

Abstract: Generation Y, children born to baby‐boomers, is widely considered to be the next big generation. Businesses are therefore struggling to find ways to capture a piece of this market. Could cause‐related marketing be the answer? Employs an experimental design to examine how college‐age Generation Y consumers respond to a cause‐related marketing (CRM) offer based on four structural elements. Also examines the potential impacts of socio‐demographic characteristics of participants. The results indicate that a CRM offer is more likely to elicit a more positive response to a disaster cause than an ongoing cause when businesses use non‐transaction‐based and long‐term/frequent support. Finds that females, social science majors, parents’ annual income and previous donation activity have significant impact on the evaluation of a CRM offer. There is a positive relationship between evaluation of a CRM offer and purchase intent toward the offer.

Detection of Feigned Mental Disorders A Meta-Analysis of the MMPI-2 and Malingering

Abstract: The validity of test data from multiscale inventories is dependent on self-reports that may be easily distorted by malingering. In examining the Minnesota Multiphasic Personality Inventory-2's (MMPI-2) role in the assessment of feigning, this review provides a conceptual analysis of the detection strategies underlying the MMPI-2 validity scales. The conceptual analysis is augmented by comprehensive meta-analysis of 65 MMPI-2 feigning studies plus 11 MMPI-2 diagnostic studies. For the rare-symptoms strategy, Fp (Cohen's d = 2.02) appears especially effective across diagnostic groups; its cut scores evidence greater consistency than most validity indicators. The data supported the F as an effective scale but questioned the routine use of Fb. Among the specialized scales, Ds appeared especially useful because of its sophisticated strategy, consistent cut score, and minimalfalse-positives. General guidelines are offeredfor specific MMPI-2 validity scales in the assessment of malingering with specific diagnoses.

Vicarious traumatization, secondary traumatic stress, and burnout in sexual assault and domestic violence agency staff.

Abstract: This study investigated three occupational hazards of therapy with trauma victims: vicarious trauma and secondary traumatic stress (or "compassion fatigue"), which describe therapists' adverse reactions to clients' traumatic material, and burnout, a stress response experienced in many emotionally demanding "people work" jobs. Among 101 trauma counselors, client exposure workload and being paid as a staff member (vs. volunteer) were related to burnout sub-scales, but not as expected to overall burnout or vicarious trauma, secondary traumatic stress, or general distress. More educated counselors and those seeing more clients reported less vicarious trauma. Younger counselors and those with more trauma counseling experience reported more emotional exhaustion. Findings have implications for training, treatment, and agency support systems.

Osteopathic manipulative treatment for chronic low back pain: a randomized controlled trial.

Abstract: Study design A randomized controlled trial was conducted. Objective To determine the efficacy of osteopathic manipulative treatment as a complementary treatment for chronic nonspecific low back pain. Summary of background data Osteopathic manipulative treatment may be useful for acute or subacute low back pain. However, its role in chronic low back pain is unclear. Methods This trial was conducted in a university-based clinic from 2000 through 2001. Of the 199 subjects who responded to recruitment procedures, 91 met the eligibility criteria. They were randomized, with 82 patients completing the 1-month follow-up evaluation, 71 completing the 3-month evaluation, and 66 completing the 6-month evaluation. The subjects were randomized to osteopathic manipulative treatment, sham manipulation, or a no-intervention control group, and they were allowed to continue their usual care for low back pain. The main outcomes included the SF-36 Health Survey, a 10-cm visual analog scale for overall back pain, the Roland-Morris Disability Questionnaire, lost work or school days because of back pain, and satisfaction with back care. Results As compared with the no-intervention control subjects, the patients who received osteopathic manipulative treatment reported greater improvements in back pain, greater satisfaction with back care throughout the trial, better physical functioning and mental health at 1 month, and fewer cotreatments at 6 months. The subjects who received sham manipulation also reported greater improvements in back pain and physical functioning and greater satisfaction than the no-intervention control subjects. There were no significant benefits with osteopathic manipulative treatment, as compared with sham manipulation. Conclusions Osteopathic manipulative treatment and sham manipulation both appear to provide some benefits when used in addition to usual care for the treatment of chronic nonspecific low back pain. It remains unclear whether the benefits of osteopathic manipulative treatment can be attributed to the manipulative techniques themselves or whether they are related to other aspects of osteopathic manipulative treatment, such as range of motion activities or time spent interacting with patients, which may represent placebo effects.

No Access, No Use, No Impact: Snapshot Surveys of Educational Technology In K-12

Abstract: There is general agreement that computing technologies have not had a significant impact on teaching and learning in K–12 in the U.S., even though billions of dollars have been spent in purchasing, equipping, and supporting the technology. Some critics of school technology use this situation to push their position that technology is not appropriate for children. Others put the failure on the backs of classroom teachers. However, based on the data we collected administering the Snapshot Survey in districts large and small around the country to approximately 4,000 K–12 classroom teachers, the reason that technology has not had an impact on teaching and learning is that students have, for all intents and purposes, not actually used the technology. Furthermore, the reason for this non-use lies not at the feet of the teachers, but rather in the very real lack of access to the technology. Having one computer in the classroom is not access, nor will it lead to significant student use. Frankly, technology...

An evaluation exercise for word alignment

Abstract: This paper presents the task definition, resources, participating systems, and comparative results for the shared task on word alignment, which was organized as part of the HLT/NAACL 2003 Workshop on Building and Using Parallel Texts. The shared task included Romanian-English and English-French sub-tasks, and drew the participation of seven teams from around the world.

Polyaniline–Silica Composite Conductive Capsules and Hollow Spheres†

Abstract: In this paper, we report on the preparation of monodisperse polyaniline (PANi)–silica composite capsules and hollow spheres on monodisperse core–gel-shell template particles. An extension of the previously reported inward growth method was used. The samples were self-stabilized without external additives. The core–gel-shell particles were prepared by the inward sulfonation of monodisperse polystyrene particles. The introduced sulfonic acid and sulfone groups are responsible for the gel properties. The gel-shell thickness and core size were synchronously controlled over the whole particle radius range. After aniline (ANi) monomer was preferentially absorbed in the sulfonated polystyrene shell, PANi was formed by polymerization. PANi was doped in situ with a sulfonic acid group to give the capsules a high conductivity. PANi hollow spheres were derived after the polystyrene cores were dissolved: their cavity size and shell thickness were synchronously controlled by using different core–gel-shell particles. The PANi–silica composite capsules and hollow spheres were therefore prepared by a sol–gel process using tetraethylorthosilicate in the conducting shell. The PANi shell became more robust while maintaining the same conductivity level. Morphological results indicate that the PANi and silica formed a bicontinuous network. Fourier-transform infrared (FTIR) spectra revealed that the hydrogen bonding in the PANi–gel shell was enhanced after the silica phase was incorporated, which could explain the high conductivity level after the silica phase was added. In a converse procedure, silica capsules and hollow spheres were prepared by a sol–gel process that incorporated tetraethylorthosilicate into the core–gel-shell templates, which was followed by the absorption and polymerization of aniline in the silica shell thus forming PANi–silica composite capsules and hollow spheres. The silica capsules and hollow spheres thereby became conductive.

Lodging quality index (LQI): assessing customers’ perceptions of quality delivery

Abstract: No matter how much effort is placed into producing quality service, the true test lies in the perception of customers. To assess this perception, lodging executives have only a few quantitative instruments available from which to choose, since the development of such scales is still in its infancy. This study takes the reader through the step‐by‐step development of a reliable and valid quantitative measuring tool that lodging practitioners can implement to measure their customers’ perception of delivered quality. The procedures followed begin with the same original dimensions that were used to develop SERVQUAL. The resulting lodging quality index (LQI) emphasizes five clearly defined dimensions of service quality.

Electrodeposition of Copper Thin Film on Ruthenium A Potential Diffusion Barrier for Cu Interconnects

Abstract: The electrochemical deposition of copper (Cu) thin film on polycrystalline ruthenium (Ru) electrode surface was investigated in a sulfuric acid plating bath. Scanning electron microscopic characterization indicated that a continuous thin Cu film (150 A and above) could be conformally coated on Ru with good control of thickness. The nucleation and growth of Cu on Ru was studied using the potentiostatic current-transient method. The results support a predominantly progressive nucleation of Cu on the Ru surface. In addition, X-ray diffraction patterns indicated (i) a principally (111) texture of the electrochemically grown Cu on Ru and (ii) the absence of any new phase or compound formation between the two metals, even after annealing up to 800°C. Scotch tape peel tests showed that Cu films adhered strongly to Ru, both before and after the annealing treatments. The lack of metallurgical interaction and strong adhesion between Cu and Ru at elevated temperatures underscore the potential application of Ru as a new Cu diffusion barrier. © 2003 The Electrochemical Society. All rights reserved.

Entrepreneurial Dispositions and Goal Orientations: A Comparative Exploration of United States and Russian Entrepreneurs

Abstract: We refine and extend the study of entrepreneurial dispositions by linking three classic hallmarks of the entrepreneur—achievement motivation, risk–taking propensity, and preference for innovation—to the goal orientations of United States and Russian entrepreneurs. The results suggest that entrepreneurial dispositions vary according to culture and the entrepreneur's primary goal for the venture. The results have important implications for theoretical development linking dispositions and entrepreneurial behavior in different settings and for entrepreneurial education and government policy.

Nanotubes in Microwave Fields: Light Emission, Intense Heat, Outgassing, and Reconstruction

Abstract: SWNTs, produced via the HiPco process, display strong microwave absorption (1.01 × 10-5 eV microwave field) with subsequent dramatic light emission, intense heat release (2000 °C), outgassing, mechanical extension, and nanotube reconstruction (welding and loop formation).

Nanoparticle-assisted microwave absorption by single-wall carbon nanotubes

Abstract: We report the effects of microwave irradiation on both unpurified and purified iron-catalyzed high-pressure disproportionation (HiPco)-grown single-walled carbon nanotubes (SWNTs) in ultrahigh vacuum. Under microwave irradiation, we observe that unpurified HiPco SWNTs quickly reach temperatures of approximately 1850 °C. As a result, H2, H2O, CO, CO2, and CH4 gases are observed, and the Fe catalyst nanoparticles melt and coalesce into larger crystallites approximately four times their original diameter. In contrast, carbon black and purified HiPco SWNTs heat up to temperatures of 500–650 °C. We propose that the significant heating of unpurified HiPco SWNTs is due to the Fe catalysts.

Some Novel Liquid Partitioning Systems: Water−Ionic Liquids and Aqueous Biphasic Systems

Abstract: Partition coefficients, as values of log P, between water and two room-temperature ionic liquids and between water and an aqueous biphasic system have been correlated with Abraham's solute descriptors to yield linear free energy relationships that can be used to predict further values of log P, to ascertain the solute properties that lead to increased or decreased log P values, and to characterize the partition systems It is shown that, in all three of the systems, an increase in solute hydrogen-bond basicity leads to a decrease in log P and an increase in solute volume leads to an increase in log P For the two ionic liquid systems, an increase in solute hydrogen-bond acidity similarly decreases log P, but for the aqueous biphasic system, solute hydrogen-bond acidity has no effect on log P These effects are rather smaller than those observed in traditional water−solvent systems However, the ionic liquids appear to have an increased affinity for polyaromatic hydrocarbons as compared to traditional orga

A fuzzy neural network for assessing the risk of fraudulent financial reporting

Abstract: While financial reporting fraud has become more prevalent and costly in recent years, fraud detection has been badly lagging. Several recent studies have examined the feasibility of various computer techniques in business and industrial applications. The purpose of this study is to evaluate the utility of an integrated fuzzy neural network (FNN) for fraud detection. The FNN developed in this research outperformed most statistical models and artificial neural networks (ANN) reported in prior studies. Its performance also compared favorably with a baseline Logit model, especially in the prediction of fraud cases.

Quinol-based cyclic antioxidant mechanism in estrogen neuroprotection

Abstract: Substantial evidence now exists that intrinsic free-radical scavenging contributes to the receptor-independent neuroprotective effects of estrogens. This activity is inherently associated with the presence of a phenolic A-ring in the steroid. We report a previously unrecognized antioxidant cycle that maintains the “chemical shield” raised by estrogens against the most harmful reactive oxygen species, the hydroxyl radical (•OH) produced by the Fenton reaction. In this cycle, the capture of •OH was shown to produce a nonphenolic quinol with no affinity to the estrogen receptors. This quinol is then rapidly converted back to the parent estrogen via an enzyme-catalyzed reduction by using NAD(P)H as a coenzyme (reductant) and, unlike redox cycling of catechol estrogens, without the production of reactive oxygen species. Due to this process, protection of neuronal cells against oxidative stress is also possible by quinols that essentially act as prodrugs for the active hormone. We have shown that the quinol obtained from a 17β-estradiol derivative was, indeed, able to attenuate glutamate-induced oxidative stress in cultured hippocampus-derived HT-22 cells. Estrone quinol was also equipotent with its parent estrogen in reducing lesion volume in ovariectomized rats after transient middle carotid artery occlusion followed by a 24-h reperfusion. These findings may establish the foundation for a rational design of neuroprotective antioxidants focusing on steroidal quinols as unique molecular leads.

Energy-aware data-centric routing in microsensor networks

Abstract: Large-scale wireless sensors are expected to play an increasingly important role in future civilian and military settings where collaborative microsensors could be very effective in monitoring their operations. However, low power and in-network data processing make data-centric routing in wireless sensor networks a challenging problem.In this paper, we propose a novel and efficient energy-aware distributed heuristic, which we refer to as EAD, to build a special rooted broadcast tree with many leaves that is used to facilitate data-centric routing in wireless microsensor networks. Our EAD algorithm makes no assumption on local network topology, and is based on residual power. It makes use of a neighboring broadcast scheduling and distributed competition among neighboring nodess. We discuss the implementation of our scheme, and present an extensive simulation experiments to study the its performance. Our experimental results indicate clearly that our EAD scheme outperforms previous schemes.

Life satisfaction, self-concept, and family relations in Chinese adolescents and children

Abstract: Subjective well-being across the life span may be affected by both age-specific and age-general factors within a cultural context. Thus, this study explored both developmentally invariant and variable predictors of life satisfaction among 115 second-graders and 74 eighth-graders from Hong Kong. In a regression model, general self-concept and ratings of parental warmth and autonomy/detachment predicted life satisfaction equally across the two age groups. However, social self-concept was a strong predictor of life satisfaction among adolescents only, whereas actual academic test scores predicted life satisfaction only among the children. Mean group differences emerged as well, with adolescents scoring significantly lower in life satisfaction and self-concept and higher in emotional detachment than children. Results are explained in relation to both development and culture.