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Saturation and foaming of thermoplastic nanocomposites using supercritical CO2.

Description: Polystyrene (PS) nanocomposite foams were prepared using supercritical fluid (SCF) CO2 as a solvent and blowing agent. PS was first in-situ polymerized with a range of concentrations of montmorillonite layered silicate (MLS). The polymerized samples were then compression molded into 1 to 2mm thick laminates. The laminates were foamed in a batch supercritical CO2 process at various temperatures and pressures from 60°-85°C and 7.6-12MPa. The resulting foams were analyzed by scanning electron microscopy to determine effect of MLS on cellular morphology. Differential scanning calorimetry was used to determine the impact of nanocomposite microstructure on glass transition of the foamed polymer. X-ray diffraction spectra suggested that the PS/MLS composite had an intercalated structure at both the 1% and 3% mixtures, and that the intercalation may be enhanced by the foaming process.
Date: May 2005
Creator: Strauss, William C.

The school reform movement and high stakes standardized testing: An analysis of factors impacting the academic outcomes of students receiving special education services.

Description: The purpose of this study was to investigate special education outcomes in relation to state standardized testing. It specifically sought to determine if a relationship existed between selected data from the Texas Academic Excellence Indicator System (AEIS) comparing district students receiving special education services TAAS scores with selected district demographic, fiscal, and special education data. The population for this study consisted of all 2001-2002 grades 3-8 and 10 public school students with the exception of charter schools, special-purpose statutory districts, and state-administered districts. The reading analysis incorporated data from 896 Texas school districts. The mathematics analysis used data from 914 school districts. Multiple linear hierarchical regression was chosen as the method for statistical analysis. Data was obtained from the Texas Education Agency (TEA) as a special data pull. For both the reading and mathematics analyses, wealth and ethnicity were statistically insignificant although ethnicity individually accounted for a large percentage of the variance for both the reading (20.3%) and mathematics (13.2%) scores as well as producing negative β weights. All other predictor variables produced varying degrees of statistical significance. Community type, socioeconomic status, instructional expenditures per students, and instructional expenditures per student receiving special education services also produced negative β weights. Two variables in this study, enrollment and the percentage of students receiving special education services tested, produced positive β weights, substantial squared structure coefficients, and positive Pearson correlation coefficients. Of these two predictors, the strongest overall positive predictor for students receiving special education services success on the grades 3-8 and 10 reading and mathematics TAAS exams was the percentage of students receiving special education services tested. These percentages produced the largest positive correlations with passing rates (reading r = .283, mathematics r = .219) and the second largest regression coefficients (reading β = .224, mathematics β = .202). They individually ...
Date: May 2005
Creator: Roach, Robert G.

Shaping Cows' Approach to Humans Using Positive and Negative Reinforcement

Description: Negative reinforcement can be a powerful tool for behavior analysts, yet it is often overlooked as a treatment method. Pryor (1999) outlines a method for approaching a "timid" animal using a combination of negative reinforcement and positive reinforcement. When the animal stands still, the human operates a clicker, and then retreats from the animal. Gradually, the human moves closer to the animal through the clicking and retreating shaping process. Once the human is standing close enough, food may be offered as a positive reinforcer, and the negative reinforcer is canceled out. The purpose of this study was to experimentally demonstrate the click-retreat technique with cows. A multiple-baseline design across subjects was used to test this technique. Results show that the click and retreat technique was effective. Results are discussed in terms of the difference between the click-retreat technique and systematic desensitization.
Date: May 2005
Creator: Morehead, Melissa L.

The stonefly genus Isogenoides Klapálek (Plecoptera: Perlodidae) of North America: Systematics, behavior and ecology.

Description: The stonefly genus Isogenoides is revised following a holomorphological approach utilizing traditional morphology and behavioral lines of evidence. Species keys are provided for all life stages. One species, I. krumholzi (Ricker) is considered a synonym of I. doratus (Frison). Detailed species descriptions are provided for males, females, nymphs and ova. Distributions are updated utilizing all known published accounts and materials examined. The vibrational communication (drumming) behavior is reported for males and all but one species for females. The signals were species-specific and ranged in complexity from ancestral sequenced duets to derived grouped exchanges. I. olivaceus is least specialized, having mostly sequenced duets, and I. zionensis most specialized, displaying ancestral sequenced, derived grouped and complex derived exchanges containing both sequenced and grouped elements. Laboratory egg incubation experiments over a 2-4 year period show that Isogenoides has a great capacity for extended, sometimes-asynchronous diapause and hatching. The eggs of six species were incubated at a single, ca. simulated San Miguel River, Colorado, seasonal temperature regime. Direct hatch within two weeks occurred only for I. zionensis (Leopard Creek, Colorado) with small numbers hatching again after one, two, and four years. Eggs of I. doratus and I. varians hatched after an over summer, 3-5 month diapause, and I. varians again in August the next year. Populations of I. colubrinus, I. elongatus, I. frontalis and San Miguel River, I. zionensis began hatching after a 9-11 month diapause and again during spring-summer temperatures in 2nd through 4th years. I. zionensis in the San Miguel River, Colorado, exhibited a semivoltine life cycle over the two-year study period. Adults emerged in June-July when stream temperature reached ca. 11-17°C. Reared females at Quartz Creek, Pitkin, Colorado, deposited up to three egg batches. Mean fecundity of females was 691 egg/female. Oviposition in the field was observed and described. Nymphal growth ...
Date: May 2005
Creator: Sandberg, John Burton

The structure and function of troponin T upon metal ion binding and the detection of nucleic acid sequence variations.

Description: Numerous troponin T (TnT) isoforms are generated by alternative RNA splicing primarily in its NH2-terminal hypervariable region, but the functions of these isoforms are not completely understood. In this dissertation work, calcium and terbium binding behavior of several forms of TnT were investigated by spectroscopic and radioactive techniques. Chicken breast muscle TnT binds calcium and terbium through its NH2-terminal Tx motif (HEEAH)n with high affinity (10-6 mM) and fast on-rate (106 - 107 M-1 s-1). Chicken leg muscle TnT and a human cardiac TnT NH2-terminal fragment, which both lack the Tx motif on their NH2-terminal regions, do not have affinities for calcium in the physiological range. Computational predictions on TnT N47 suggest that the TnT NH2-terminal region might fold into an elongated structure with at least one high affinity metal ion binding pocket comprised primarily of the Tx motif sequence and several lower affinity binding sites. In addition, calcium binding to TnT N47 might alter its conformation and flexibility. Luminescence resonance energy transfer measurements and other experimental observations are consistent with the computational predictions suggesting the computational simulated atomic model is reasonable. TnT mutations are responsible for 15% of familiar hypertrophic cardiomyopathy (FHC) cases with a phenotype of relatively mild hypertrophy, but a high incidence of sudden death. Detection of those genetic mutations would facilitate the clinical diagnosis and initiation of treatment at an early stage. This dissertation also investigated a novel hybridization proximity assay (HYPA) combining molecular beacon and luminescence resonance energy transfer (LRET) technologies. Experimental results suggest that a shared stem probe design produces a more consistent response upon hybridization, whereas the internally labeled probe was less consistent, but can yield the highest responses. Using the optimally designed molecular probes, the HYPA provides a detection of alterations in nucleic acid structure of as little as a single nucleotide. ...
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Date: May 2005
Creator: Zhang, Zhiling

Treadmill validation of the Siconolfi step test.

Description: Maximal oxygen uptake (VO2max) is the internationally recognized measure of a person's cardiorespiratory fitness. Currently the most accurate way of assessing one's true VO2max involves the use of maximal exercise tests, which require the use of specialized equipment, and are time consuming and costly. The purpose of this study was to determine the validity of the submaximal Siconolfi step test to estimate VO2max. A second purpose was to determine if body fat percentage improved the validity. Thirty-six individuals underwent a maximal treadmill test, in which VO2max was directly measured, and the step test. Results indicate that, although VO2max estimates generated by the Siconolfi step test are highly correlated to true VO2max (r =.887; p<.01), the values consistently underestimated a person's aerobic fitness. It was also determined that body fat percentage did not contribute to the prediction of VO2max.
Access: This item is restricted to the UNT Community Members at a UNT Libraries Location.
Date: May 2005
Creator: Harkrider,Tiffani L.

Treatment Outcomes Related to EEG-Biofeedback for Chemical Dependency: Changes in MMPI-2™ (University of Minnesota) Personality Measures and Long Term Abstinence Rates

Description: Peniston and Kulkosky (1989, 1990) demonstrated the effectiveness of alpha-theta EEG-Biofeedback (EEG-BFB) in treating inpatient alcoholics noting significant improvements in depression, psychopathology, serum β-endorphin levels, and abstinence rates. The present study is an extension of a previously unpublished replication of the Peniston EEG-BFB protocol with 20 chemically dependent outpatients (Bodenhamer-Davis, Callaway, & DeBeus, 2002). Fifteen subjects were "high risk for re-arrest" probationers. Data for the EEG-BFB group was collected from archival records. Subjects completed an average of 39 sessions (SD = 6.096), with 33 of those being EEG-BFB. Pre/post-treatment MMPI-2s™ (University of Minnesota) were collected and follow-up (4-11 years) data obtained (abstinence rates, re-arrests in some cases). Treatment effects were evaluated by comparing assessment data (pre/post) and documenting abstinence rates. Post-treatment MMPI-2 results were within normal limits, with several scales significantly reduced from baseline suggesting less psychopathology. Results were then compared to 20 subjects receiving standard addiction treatment (OT-CD group), but not EEG-BFB. OT-CD subjects completed a 2-week inpatient program followed by 18 outpatient sessions. Pre/post assessment and follow-up data was collected on the OT-CD group. The OT-CD group's post-assessment results showed three elevations (MMPI-2 scales 4/6/8), suggestive of characteriological problems. Post-MMPI-2 results of the two groups were compared via ANCOVAs. Findings indicated no significant differences between groups on targeted scales; however, there was a trend for the EEG-BFB group to have lower scores. Follow-up data was obtained on 13 EEG-BFB subjects. Results indicated 92% (n = 12) were sober, with 8% (n = 1) claiming significantly reduced alcohol intake. Probationer re-arrest and revocation rates were collected on the subset of probationers (n = 14 out of 15). The majority of the probationers (79%, n = 11) had not been re-arrested nor had their probation been revoked. Short-term follow-up information (35-131 days post-assessment), available at the time of writing, for ...
Date: May 2005
Creator: Callaway, Tonya Gayle

A two-year college typology for the 21st century: Updating and utilizing the Katsinas-Lacey classification system.

Description: This study had two primary purposes. The first goal was to bring the 1993/1996 Katsinas-Lacey two-year college classification system into the 21st century using data from the 2000 United States Census and the National Center for Education Statistics' Integrated Postsecondary Educational Data System (IPEDS) surveys for the 2000-2001 and 2001-2002 academic years. The second goal was to create a descriptive portrait of the universe of two-year, publicly controlled institutions that primarily offer the associate's degree mapped against the updated classification system and to describe and discern similarities and differences within this particular population by class and subclass in terms of multiple measurable characteristics for which IPEDS data were available. The study, based upon classification theory utilized in social science and management sciences - particularly the work of Bailey and McKelvey - assessed the efficacy of a number of other recent proposed community college classification systems, the original Katsinas-Lacey system and the revised version of Katsinas-Lacey created through the current research. It found both the original Katsinas-Lacey system and the revised version to meet the criteria for a well-made classification model. The study includes directories of all colleges and universities in the United States that offer the associate's degree with geographic, census population data, number of campuses and 2000-2001 unduplicated enrollment data for publicly controlled, two-year colleges and districts. Also included are data tables illustrating similarities and differences between colleges and districts in the three major classes and seven subclasses of publicly controlled institutions drawn from IPEDS survey data and detailed profiles of each of these institutional types - Rural, Rural Small, Rural Medium, Rural Large, Suburban, Suburban Single Campus, Suburban Multi-Campus, Urban, Urban Single Campus, and Urban Multi-Campus. The study concludes with a review of implications for policy and practice, and 25 recommendations for further research related to the revised ...
Date: May 2005
Creator: Hardy, David Earl

Using video modeling to teach complex play sequences to children with autism.

Description: Overcoming social skill deficits in children with autism is a challenge faced by educators and caregivers. Video modeling is a method of training that can promote generalization. This study extends the literature by investigating effects of video modeling on repetitive motor and vocal responses and skill generalization to other settings for children with low-functioning autism/ developmental disabilities. A multiple baseline across 3 play sequences was implemented with 3 males. Results indicate that 2 acquired vocal and motor responses and 1 acquired imitative noises and motor responses using video modeling alone. Generalization occurred with 2 participants. These findings have important implications for the field showing that video modeling can enable educators and caregivers to help children with autism overcome social skill deficits.
Date: May 2005
Creator: Jeffreys, Chris

Validation of clinical screens for suicidality and severe mental disorders for jail inmates.

Description: Psychologists and other mental health professionals working in correctional institutions bear the considerable responsibility for identifying, diagnosing, and treating mentally disordered inmates. The importance of these responsibilities has been recognized in recent years because of the burgeoning population of inmates in general and the higher numbers of inmates with mental illness in particular. Research has demonstrated that the screens currently used in correctional settings to identify mentally disordered and suicidal inmates are either unvalidated or generally ineffective. This study investigates the validity of different mental health screens in a jail population. Inmates from the Grayson County Jail were administered three screens: the Referral Decision Scale (RDS), Personality Assessment Screener (PAS), and the Mental Disability/Suicide Intake Screen (MDSIS). Criterion measures were the Schedule for Affective Disorders and Schizophrenia (SADS) for Axis I disorders and the Suicide Probability Scale (SPS) for suicidal ideation. Results indicate that each screen most effectively assessed one clinical domain: the RDS for psychosis, the MDSIS for suicidality, and the PAS for depression. Gender differences were observed in screen items most effective for classifying inmates by suicide risk level.
Date: May 2005
Creator: Harrison, Kimberly S.

The Waning of Victorian Imperialism: Stylistic Dualism in Gustav Holst's One-Act Opera Sāvitri (1908-9)

Description: Gustav Holst's one-act opera Sāvitri (1908-9) represents a turning point in his compositional style, which came at a significant time in British history. Holst combines a simpler style informed by his work with English folksong with the Wagnerian style that permeated his earlier compositions. Although influenced by a British imperialist view of the world, Sāvitri renders Hindu-Indian culture in positive terms without relying on the purely exotic, offers a perspective on gender relationships that does not depend solely on convention, and presents the commoner as the British ideal rather than romanticizing the aristocracy. The result is an opera subtle in its complexity, approaching the profound themes of love, death, and spirituality with emotional restraint and self-control.
Date: May 2005
Creator: Broughton, Joseph Earl

Weak states, human rights violations, and the outbreak of civil war.

Description: In recent years, explanations for the occurrence of civil war have mainly emphasized state weakness as providing an opportunity for greed-based rebellions. Yet, this explanation leaves many questions open, as it cannot distinguish between weak states that do and those that do not experience civil war. In this paper, I argue that abuses of personal integrity rights, committed or sponsored by the government, provide this missing link. The theory is illustrated and formalized in a game-theoretic model and then tested empirically, building on earlier work by Fearon and Laitin (2003a) and Sambanis (2004). The results show that repression is highly significant in both statistical and substantive terms. According to one model, the probability of civil war onset increases by a factor of almost 16 in highly repressive countries compared to countries with no repression. Further robustness tests across alternative civil war lists largely confirm the importance of human rights abuses in explaining the occurrence of civil war.
Date: May 2005
Creator: Rost, Nicolas

Workplace Violence Prevention Training: An Analysis of Employees' Attitudes

Description: The purpose of this study was to determine employees' attitudes and perceptions toward the effectiveness of workplace violence prevention training within a U.S. Government service agency with 50 offices located in Minnesota and Wisconsin. Chapter 1 presents an overview of the phenomenon of workplace violence, the movement toward prevention programs and policies and the implementation of prescreening processes during hiring and violence prevention training. Chapter 2 contains a thorough review of pertinent literature related to violence prevention training and the impact of occupational violence on organizations. This topic was worthy of research in an effort to make a significant contribution to training literature involving organizational effectiveness due to the limited amount of research literature covering the area of corporate violence prevention training and its effect on modifying attitudes and behaviors of its customers. The primary methodology involved the assessment of 1000 employees concerning their attitudes and perceptions toward the effectiveness of workplace violence prevention training. The research population were administered a 62 item online assessment with responses being measured, assessed, and compared. Significant differences were found calling for the rejection of the three study hypotheses. Chapter 4 described the findings of the population surveyed and recommendations were identified in Chapter 5.
Date: May 2005
Creator: Adriansen, David J.

Chemical Information Bulletin, Volume 57 Number 1, Spring 2005

Description: Created as a supplement for "the regular journals of the American Chemical Society," this publication contains annotated bibliographies of chemical documentation literature as well as information about meetings, conferences, awards, scholarships, and other news from the American Chemical Society (ACS) Division of Chemical Information (CINF).
Date: Spring 2005
Creator: American Chemical Society. Division of Chemical Information.

Journal of Near-Death Studies, Volume 23, Number 3, Spring 2005

Description: Quarterly journal publishing papers related to near-death experiences, including research reports; theoretical or conceptual statements; expressions of a scientific, philosophic, religious, or historical perspective on the study of near-death experiences; cross-cultural studies; individual case histories; and personal accounts of experiences or related phenomena.
Date: Spring 2005
Creator: Greyson, Bruce

Letters to the Editor

Description: Three letters written to the editor of the Journal of Near-Death Studies on the following topics: "Cardiac Arrest and Near-Death Experiences," a commentary on 'Cardiac Arrest and Near-Death Experiences," and "Woerlee Responds."
Date: Spring 2005
Creator: Punzak, Dan; Ford, Oral I. & Woerlee, G.