Search Results

Texas Public School Principals' Application of Procedures in Identification and Prevention of Sexual Harassment

Description: The procedural survey on sexual harassment procedures sent to 300 Texas principals had a response rate of 48.3 %. The mean score on the procedural survey for all 300 principals was 69.30 %. Eighteen research questions were addressed in detail in Chapter 4. Only five showed a significant correlation or effect size. Question 5 asked if there was a correlation between gender and the mean score of the survey instrument regarding sexual harassment procedures. The mean score of women was significantly higher than men. Question 6 asked if there was a correlation between the number of students in a school and the mean score of the survey instrument regarding sexual harassment procedures. This revealed that a significant correlation appeared between principals who worked at larger schools. Question 10 asked if there was a correlation between the location of the school, whether rural, urban, or metroplex and the mean score of the survey instrument. Principals of urban and metroplex schools scored significantly higher. Question 13 asked if there was a correlation between the hours of sexual harassment training attended in the last year and the mean score of the survey instrument regarding sexual harassment procedures. The results of this analysis revealed that a correlation approaching a medium effect size of .237 was present. Question 18 asked if there was a correlation between the total number of hours a principal had attended training and the mean score of the survey instrument. Neither the Pearson's correlation or the Spearman's rho was statistically significant. However, due to the large variation in responses on the sum of hours of training about sexual harassment, it was suspected that there might be a covariate accounting for sub-populations within the principals who participated in the survey. For ages 30-43.5, as the number of total training hours increased, the ...
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Date: May 2002
Creator: Cramer, Conita K. Markel
Partner: UNT Libraries

Fluorination Effect on the Conformational Properties of Alkanes

Description: A Series of fluorophores of the general formular P(CF2)nP and P(CF2)n-1CF3 has been synthesized. Copper catalyzed coupling of 1-bromopyrene and the corresponding mono and di-iodoperfluoroalkanes were used in most cases. For the n=3 dimer, a novel 1,w-perfluoroalkylation of pyrene via bis-decarboxylation of hexafluorogultaric acid was utilized. These compounds, along with suitable hydrocarbon analogs, are being used to study the flexibility of fluorocarbon chains using emission. We have found that the excimer formation for the fluorinated pyrene monomers is highly dependent on concentration and is less efficient than for pyene. Excimer formation for the fluorinated pyrene dimers is much more efficient than for the fluorocarbon monomers and is only slightly concentraion dependent. Steady-state emission spectra indicate hydrocarbon dimers-models form excimers more efficiently than the fluorinated dimers suggesting the fluorinated chains are stiffer than the hydrocarbons. We conducted the temperature-dependent studies and quantified the conformational difference.
Date: May 2002
Creator: Xu, Wenjian
Partner: UNT Libraries

The Characteristics of Sociological Practitioners: A Social Psychological Examination

Description: Questionnaires were sent by mail and e-mail to 143 members of the Sociological Practice Association. The purpose of the questionnaire was to measure the role expectations as qualities (competencies), role expectations as actions, and role enactments of the respondents'. An additional goal was to examine how respondents perceived their work to be sociological in nature, and how they saw their work as different from the practices of social workers, counselors, and psychologists. The first question that was addressed was, “Do sociological practitioners have clear and unambiguous role expectations for their work as practitioners?” The data showed that most role expectations measured as competencies were clear and unambiguous, and only a few were ambiguous and unclear. The second question addressed was, “Do sociological practitioners perceive their role enactments to differ from other helping professionals such as social workers, counselors, and psychologists?” The data showed that sociological practitioners do perceive their role enactments to be different because of their use of sociological theory and their focus on social structures. The final question asked was, “How do sociological practitioners perceive their work as sociological in theory, methods, or both?” The data showed that sociological practitioners perceive their work as sociological based on their use of sociological theory. Most respondents reported that they used common scientific methods, and few reported the use of psychological theory.
Date: May 2002
Creator: Carr, Joel Lance
Partner: UNT Libraries

Use of the Beck Depression Inventory in Northern Brazil

Description: The Beck Depression Inventory (BDI) is a popular screening and research instrument for measuring severity of depression. The instrument was translated to Portuguese for use in Brazil in 1979; however, it was not until recently that its psychometric properties have been tested empirically for the Brazilian population. The purpose of the present study was to explore the BDI's psychometric properties in a northern region of Brazil and to test for possible relationships between certain demographic variables and BDI outcomes. Samples used in this study were from an urban area in Roraima, the northernmost state of Brazil. The BDI showed adequate levels of internal consistency in nonclinical and clinical samples. Female respondents had significantly higher scores than male respondents. Those who had lower levels of education, income, or occupational status had significantly higher scores than those with higher levels of these variables. Adolescents had significantly higher scores than adults from all age groups except those from age 19 to 22. No significant difference was found between those who identified themselves as “indigenous” and those who identified themselves as “non-indigenous.” Regression analysis results showed that the combination of gender, education, and age best accounted for the variance in BDI scores. An ANCOVA revealed that clinically depressed adults had significantly higher BDI scores than nonclinically depressed adults. Factor analysis results showed that there were two main factors in the item structure for both female respondents and male and female respondents combined: one factor of mainly cognitive-affective items and the other factor of mainly somatic items. The results were discussed in terms of the future use of the BDI in Brazil.
Date: May 2002
Creator: Albert, Christopher
Partner: UNT Libraries

The Construct Validity of Self-Reported Historical Physical Activity

Description: The purpose of this study was to determine the construct validity of self-reported historical walking, running, and jogging (WRJ) activity. The criterion measure was concurrent performance on a maximal treadmill test. Subjects completed a medical exam and treadmill test between the years 1976 and 1985, and completed a follow-up questionnaire in 1986. Questionnaire included an item that assessed WRJ for each year from 1976 through 1985. Data analysis included Spearman correlations, partial correlations, ANOVA, and ANCOVA. Results indicated self-reported historical WRJ can be assessed with reasonable validity when compared with concurrently measured treadmill performance, and there is no decay in the accuracy of this reporting for up to ten years in the past.
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Date: May 2002
Creator: Bowles, Heather R.
Partner: UNT Libraries

Strategic Versus Sincere Behavior: The Impact of Issue Salience and Congress on the Supreme Court Docket

Description: The theory proposed here is that the Supreme Court behaves in a strategic manner at the agenda-setting stage in order to vote sincerely on the merits. To test this, I measure the impact issue salience and ideological distance between Congress and the Supreme Court has on the agenda. The results indicate that whether the Supreme Court behaves either sincerely or strategically depends on the policy area. The strategic nature of the Supreme Court at the agenda-setting phase may be in large part why some research shows that the Court behaves sincerely when voting on the merits. By behaving strategically at the agenda-setting phase, the Court is free to vote sincerely in later parts of the judicial process.
Date: May 2002
Creator: Williams, Jeffrey David
Partner: UNT Libraries

Lucca in the Signoria of Paolo Guinigi, 1400-1430

Description: This study analyzes the once great medieval Tuscan capital of Lucca's struggle for survival at the beginning of the fifteenth century. This was the age of the rise of regional states in Italy, and the expansionistic aims of Milan, Florence and others were a constant challenge to city-states such as Lucca which desired a political and cultural status quo. Yet, it was a challenge that was successfully met; unlike Pisa, Siena, Perugia, and various other major Tuscan cities, Lucca did not succumb to Milanese or Florentine aggression in the early Quattrocento. Why it did not is a major topic of discussion here. One of the means in which the Lucchese faced the new political and military realities of the time was the establishment of a monarchial system of government in the signoria of Paolo Guinigi (r. 1400-1430). The Guinigi Signoria was not characterized by the use of intimidation and violence, but rather by clientage, kinship and neighborhood bonds, marriage alliances, and the general consent of the people. Paolo garnered the consent of the people at first because his wealth allowed him to protect Lucca and its contado to a greater extent than would have been possible otherwise, and because of his family's long ties with the powerful Visconti of Milan; he held it later because he provided the city-state with capable leadership. This study extends the evidence of recent scholars that every Italian Renaissance city was unique based on its particular geography, alliances, civic wealth, and a number of other factors. Lucca in the period of Paolo Guinigi, a monarchy in the setting of one of the traditionally most republican cities of Italy, provides a most interesting example. “Civic humanism,” for example, has a decidedly different slant in Lucca than elsewhere, and is best exemplified in the figure of Giovanni ...
Date: May 2002
Creator: Johnson, Ken
Partner: UNT Libraries

The Effects of Non-differential Reinforcement and Differential Reinforcement on Problem Behaviors and Accuracy of Responding of Autistic Children.

Description: The effects of non-differential reinforcement and differential reinforcement on problem behaviors and accuracy of responding of autistic children was examined. In experiment 1, one child with autism participated, and in experiment 2, two children with autism participated. In the non-differential reinforcement condition both prompted and unprompted responses were reinforced. In the differential reinforcement condition only unprompted responses were reinforced. Overall, problem behaviors were more frequent in the non-differential reinforcement condition. In experiment 1, accuracy was higher in the differential reinforcement condition, while experiment 2 showed inconclusive results with regards to accuracy. It is concluded that non-differential reinforcement can decrease problem behaviors in teaching situations, but may not be sufficient to ensure acquisition of target tasks.
Date: May 2002
Creator: Ingvarsson, Einar Thor
Partner: UNT Libraries

Competency to Stand Trial: A Systematic Evaluation and Validation of the GCCT, MacCAT-CA, and ECST as Competency Measures

Description: Competency to stand trial cases constitute the largest percentage of forensic referrals for clinical psychologists. Furthermore, research suggests that the use of forensic measures facilitates the decisions of competency made by forensic examiners. This study investigated the construct validity of three competency measures: (a) the GCCT-MSH, (b) the MacCAT-CA, and (c) the ECST with 100 adult males incarcerated at the Tarrant County Jail in Fort Worth, TX. Construct validity was investigated via the use of a multitrait-multimethod research design for the three-prong conceptualization of the Dusky standard. Results indicated that current competency measures do an adequate job of assessing for factual understanding, but lack construct validity for two prongs: rational understanding and the ability to consult with counsel. In addition, the atypical presentation scales of the both GCCT and the ECST performed well at screening individuals for feigning. Finally, prediction of competency from clinical variables was also investigated. Psychotic symptoms and overall impairment were the strongest predictors of incompetency.
Date: May 2002
Creator: Grandjean, Nicole Rae
Partner: UNT Libraries

Sonata for Piano (1963) by Sergei Michailovich Slonimsky: Musical Analysis and Discussion on Interpretation and Performance

Description: The essay begins with the overview of Russian-Soviet piano music from the second half of the 19th century to the end of the 20th century. Then, biographical information about Sergei Slonimsky and an overview of his major compositions is provided. The majority of the paper focuses on Slonimsky's Sonata for Piano (1963). A brief discussion of the Sonata's compositional history is followed by the formal analysis of the overall structure of the work. Slonimsky's original principle of organization of the music is emphasized: the system of constant interrelation of the main thematic material combined with elements of the sonata-allegro form. In the analysis of the harmonic language of the piece, the composer's extensive use of Russian folk elements such as diatonic melodies, sigh motives, parallel triads, and simultaneous use of the lower third with the major triad is pointed out. The rest of the paper focuses on issues of interpretation and performance. Special notice is given to the problem of incorporating a percussive type of playing with the elements of folk cantilena singing. The paper concludes with the history of Sonata's performances and a discussion of current recordings.
Date: May 2002
Creator: Fitenko, Nikita
Partner: UNT Libraries

Supply chain relationships in apparel retail product development.

Description: The purpose of this study was to investigate supply chain relationships within the apparel retail product development process under a single site case study setting. Relationship determinants (i.e. drivers, facilitators and barriers) that facilitated or impeded the degree of collaborative efforts between the retailer and the supply chain members were identified. As the retailer integrated its product development process with its suppliers, a triangular relationship was formed between the retailer, the overseas manufacturers, and the designated suppliers. The study found that the retailer sought operational efficiency in its business relationships with supply chain members, but continued to seek long-term commitment in these relationships to establish a virtual vertical company.
Date: May 2002
Creator: Lee, Daton
Partner: UNT Libraries

An Analysis of the Effectiveness of Computer Assisted Instruction in General Chemistry at an Urban University.

Description: The science-major General Chemistry sequence offered at the University of Houston has been investigated with respect to the effectiveness of recent incorporation of various levels of computer technology. As part of this investigation, questionnaire responses, student evaluations and grade averages and distributions from up to the last ten years have been analyzed and compared. Increased use of web-based material is both popular and effective, particularly with respect to providing extra information and supplemental questions. Instructor contact via e-mail is also well-received. Both uses of technology should be encouraged. In contrast, electronic classroom presentation is less popular. While initial use may lead to improved grades and retention, these levels decrease quickly, possibly due to a reduction in instructor spontaneity.
Date: May 2002
Creator: McGuffey, Angela
Partner: UNT Libraries

Graduate Professional Training in Christian Education at Dallas Theological Seminary and Alumni Perceptions of Program Quality

Description: This study assessed the quality of graduate professional training in Christian education at Dallas Theological Seminary (DTS) in terms of the perceptions of program alumni. The subjects of the investigation were 780 alumni who graduated from DTS between 1984 and 2000. The Christian Education program was assessed utilizing Daniel Stufflebeam's CIPP model and alumni data collected from a survey instrument. A response rate of 65% (N=504) was achieved. The research procedure employed a non-experimental design methodology for the quantitative component and open-ended questions for the qualitative component. Most results were statistically significant at the .05 alpha level utilizing chi-square goodness-of-fit tests.
Date: May 2002
Creator: McLaughlin, Linden D.
Partner: UNT Libraries

A Behavioral Economic Analysis of the Effects of Unit Price Sequence on Demand for Money in Humans.

Description: Three groups of participants were exposed to different unit price sequences. Unit prices for all groups ranged from unit price 1 to 21. Analyses of demand curves, response rates, session duration, and elasticity coefficients suggest that the sequence of exposure to unit prices can affect the elasticity of demand. In addition, the size of unit price contrast, direction of unit price change, and proximity to experimental milestones also may affect the consumption of monetary reinforcers.
Date: May 2002
Creator: Williams, Jack Keith
Partner: UNT Libraries

An evaluation of job satisfaction among salespersons in a small department store using four psychological measures.

Description: The purpose of this study was to examine the potential of three independent psychological scales (Rotter's Locus of Control, Karasek's Job Content Questionnaire [non-injury job stress], and Rosenberg's Self-Esteem Scale) to predict job satisfaction, as measured by Brayfield and Rothe's Index of Job Satisfaction, among salespersons in a small independent department store in Wichita Falls, Texas. An 82-item survey which examined the dynamics of a salesperson's work life was administered to 20 individuals who were full-time employees of the department store. Demographic data were also gathered although these factors were not entered into the regression analysis. A multiple regression procedure examined the responses of the 20 employees who participated in the study. The R-squared coefficient indicates that 41 percent of the variance in Job Satisfaction was explained by the three predictor measures. A major proportion of this unexplained variance may be in variables outside the scope of this study, e.g., salaries, vacation time, benefits, bonuses, or commissions. Results suggest that the independent variables measured by the Locus of Control Scale and the Job Content Questionnaire in combination were the best predictors of job satisfaction with a significance level of .01. The single best predictor was the Job Content Questionnaire, significant at .03. The three instruments (Locus of Control, Self-Esteem, and Job Content Questionnaire) which comprised the independent variables, reached a significance level of .03 in their prediction of job satisfaction (Brayfield-Rothe Index of Job Satisfaction). Study results indicate that a majority of the employees in the sample population were satisfied with their jobs and with the leadership style manifested by the store manager. In addition, job security was believed to be satisfactory. Inasmuch as there is a void in the literature regarding personal characteristics of salespersons as variables that interact with job satisfaction, comparisons of the findings of this research ...
Date: May 2002
Creator: Webb, Ruth Sherrill
Partner: UNT Libraries

Marxian and Weberian theory as explanations of the effects of industrialization on town development: A case study; Denison, Texas.

Description: While a great deal of historical literature has concentrated on the effects of industrialization on town development, most of the accounts relate to the introduction of industrialization into an established town. This study attempts to analyze, in sociological terms, the effects of industrialization (in this case, the emergence of the railroad) on the social structure of Denison, Texas which was created by industrialization. It is an attempt to combine Marxian and Weberian theory to produce a multi-dimensional theory that can explain town development without the usual economic bias as evident in most contemporary theory. This study proceeds on the assumption that the social order of a newly formed community is not based solely on economic factors. While economic considerations were important for the town of the study, social stability of the town was maintained by other “non-economic” elements. The purpose of the study is to construct a composite theory that can be utilized to analyze town development. The thrust is not the creation of new theory, rather it attempts to combine existing “classical” theories to present a balanced and, to an extent, “objective” explanation of community development. Adding the social aspects of Weber's theory to Marx's theory results in a theory that limits the economic bias associated with pure Marxian theory.
Date: May 2002
Creator: White, Jack A.
Partner: UNT Libraries

Molecular cloning and analysis of the genes for cotton palmitoyl-acyl carrier protein thioesterase (PATE) and Δ-12 fatty acid desaturase (FAD2-3) and construction of sense and anti-sense PATE plasmid vectors for altering oilseed composition of transgenic cotton plants.

Description: A cotton PATE cDNA clone has a 1.7-kb insert with an coding region for 410 amino acids, lacking codons for the three N-terminal amino acids. The predicted amino acid sequence of the PATE preprotein has a characteristic stromal-targeting domain and a 63% identity to the Arabidopsis FatB1 thioesterase sequence. A cotton genomic clone containing a 17.4-kb DNA segment was found to encompass a palmitoyl-ACP thioesterase (FatB1) gene. The gene spans 3.6 kb with six exons and five introns. The six exons are identical in nucleotide sequence to the open reading frame of the corresponding cDNA, and would encode a preprotein of 413 amino acids. The preprotein is identified as a FatB thioesterase from its deduced amino acid sequence similarity to those of other FatB thioesterase preproteins. A 5'-flanking region of 914 bp was sequenced, with the potential promoter/enhancer elements including basic helix-loop-helix elements (E box). Alkaline blot hybridization of cotton genomic DNA suggests the presence at least two FatB1 thioesterase genes in cotton. Four plasmid constructs for both constitutive and seed-specific anti-sense RNA suppression and gene-transgene co- suppression of PATE gene expression were successfully generated. Two overlapping cotton genomic clones were found to encompass a Δ-12 fatty acid desaturase (FAD2-3) gene. The continuous FAD2-3 coding region is 1,155 bp and would encode a protein of 384 amino acids. The FAD2-3 gene has one large intron of 2,967 bp entirely within its 5'-untranslated region. Several potential promoter/enhancer elements, including several light responsive motifs occur in the 5'-flanking region. Yeast cells transformed with a plasmid construct containing the cotton FAD2-3 coding region accumulate an appreciable amount of linoleic acid (18:2), not normally present in wild-type yeast cells, indicating that the gene encodes a functional FAD2 enzyme.
Date: May 2002
Creator: Nampaisansuk, Mongkol
Partner: UNT Libraries

Detecting the Presence of Disease by Unifying Two Methods of Remote Sensing.

Description: There is currently no effective tool available to quickly and economically measure a change in landmass in the setting of biomedical professionals and environmental specialists. The purpose of this study is to structure and demonstrate a statistical change-detection method using remotely sensed data that can detect the presence of an infectious land borne disease. Data sources included the Texas Department of Health database, which provided the types of infectious land borne diseases and indicated the geographical area to study. Methods of data collection included the gathering of images produced by digital orthophoto quadrangle and aerial videography and Landsat. Also, a method was developed to identify statistically the severity of changes of the landmass over a three-year period. Data analysis included using a unique statistical detection procedure to measure the severity of change in landmass when a disease was not present and when the disease was present. The statistical detection method was applied to two different remotely sensed platform types and again to two like remotely sensed platform types. The results indicated that when the statistical change detection method was used for two different types of remote sensing mediums (i.e.-digital orthophoto quadrangle and aerial videography), the results were negative due to skewed and unreliable data. However, when two like remote sensing mediums were used (i.e.- videography to videography and Landsat to Landsat) the results were positive and the data were reliable.
Date: May 2002
Creator: Reames, Steve
Partner: UNT Libraries

Working Whiteness: Performing And Transgressing Cultural Identity Through Work

Description: Early in Richard Wright's Native Son, we see Bigger and his friend Gus “playing white.” Taking on the role of “J. P. Morgan,” the two young black men give orders and act powerful, thus performing their perceived role of whiteness. This scene is more than an ironic comment on the characters' distance from the lifestyle of the J. P. Morgans of the world; their acts of whiteness are a representation of how whiteness is constructed. Such an analysis is similar to my own focus in this dissertation. I argue that whiteness is a culturally constructed identity and that work serves as a performative space for defining and transgressing whiteness. To this end, I examine work and its influence on the performance of middle class and working class whiteness, as well as how those outside the definitions of whiteness attempt to “play white,” as Bigger does. Work enables me to explore the codes of whiteness and how they are performed, understood, and transgressed by providing a locus of cultural performance. Furthermore, by looking at novels written in the early twentieth century, I am able to analyze characters at a historical moment in which work was of great import. With the labor movement at its peak, these novels, particularly those which specifically address socialism, participate in an understanding of work as a performative act more than a means to end. Within the context of this history and using the language of whiteness studies, I look at how gendered whiteness is transgressed and reinforced through the inverted job-roles of the Knapps in Dorothy Canfield's The Home-Maker, how work can cause those who possess the physical attributes of whiteness to transgress this cultural identity, as the Joads in The Grapes of Wrath demonstrate, and how the ascribed identities as non-white for Sara in The ...
Date: May 2002
Creator: Polizzi, Allessandria
Partner: UNT Libraries

Effects of Sublethal Copper Exposure on Escape Behavior and Growth of Rana pipiens Tadpoles

Description: This research is designed to test how sublethal exposure to copper affects tadpole predator-escape behavior and how quickly tadpoles recover. After exposure, tadpoles were separated. Escape behavior was recorded for two-thirds of exposed tadpoles while one-third of the exposed population was measured weekly to determine growth and recovery. Control tadpoles were consumed within 15 minutes whereas those exposed to higher concentrations were consumed at a slower rate, which does not support the hypotheses. Although the rate of predation was lower, tadpoles exposed to higher Cu concentrations were on average, 1.47 cm in total body length. Those exposed to 0.93 mg/L averaged 0.86 cm. After being placed into clean water, treatment tadpoles recovered after 20 days.
Date: May 2002
Creator: Redick, Melinda
Partner: UNT Libraries

A Content Analysis of Reading Software Commercially Available for Pre-K to 3rd Grade Children.

Description: The purpose of this qualitative study was to investigate the content and characteristics of the currently available commercial reading software for Pre-K through third grade children. The design of the study was a content analysis. Based on the evaluation rubric established by the researcher, ten commercial reading software were selected to be analyzed. By reviewing and transcribing, the data were obtained, and then coded, categorized, and interpreted. The findings from the analysis revealed that all reading software programs offered exercised for practicing basic phonics skills; the alphabetic principle, letter-sound association, word knowledge, sentence building, and reading comprehension. Depending on the software developers, phonics-based practice was presented in two ways; separate skill-based practice emphasis and storybook-reading emphasis. All software programs utilized drill-and-practice, direct instruction and mastery learning methods and utilized gaming strategies to motivate and engage the learners. Multimedia technology was used to make the software more appealing. All reading software programs were developed on the perspectives that view learning to read as the continuum of a child's oral language development and background experience about words. It is recommended that parents and teachers review and select the software based on reliable information sources, use the software as supplementary practice based on the learning objectives identified and individual student needs.
Date: May 2002
Creator: Nakjan, Sutat
Partner: UNT Libraries

Mentoring the first-year superintendent in Texas public schools.

Description: This study determined what mentoring experiences first-year superintendents have had and what they need from a mentoring relationship. Structured interviews and field notes were used in this qualitative study focused on Texas first-year superintendents' perceived needs from mentors. Three patterns of mentoring relationships were found: 1) no mentor in the first year, 2) mentor-protégé relationship - those who developed mentoring relationships early in a career with a more senior person in the same school system, and 3) mentoring relationships of convenience - young relationships which developed outside the same system. Skills and knowledge areas novice superintendents identified as critical for mentor assistance were school finance, development of effective relationships with groups that have expectations of the superintendent while also improving student achievement, and working within the politics of the position. Mentor characteristics novice superintendents considered necessary for a positive effect on job success include: trustworthiness, confidentiality, empathy, encouraging, active listening, and integrity. An attitude in which the mentor problem solved with the protégé, and did not give an immediate solution was displayed. Mentors actively and frequently initiated contact. Ideas were freely exchanged, giving the protégé undivided attention while not making the protégé feel inferior. The effects that previous mentoring experiences had on novice superintendents influenced whether they chose to mentor another person. Most reported seeking or engaged in a new mentoring relationship. Differences in areas where help was needed among first-year superintendents associated with district size were reported. Assistance in finance was needed regardless of district size, gender, or ethnicity. Superintendents in small districts reported needing assistance in specific skill and knowledge areas. Those in larger districts reported mentor assistance in problem-solving processes to accomplish a task. Differences in needs of first-year superintendents based on gender or ethnicity were identified but generalizations could not be made due to small numbers. ...
Date: May 2002
Creator: McNulty, Rock Edward
Partner: UNT Libraries

Autoradiographic Localization of Carbachol-Induced Second Messenger Response in the Rat Spinal Cord Following Inflammation.

Description: This study examined central mechanisms of persistent pain using an autoradiographic technique to localize phosphoinositide hydrolysis (PI) in the rat spinal cord dorsal horn. The lateral half of laminae I-II showed the highest levels of baseline PI turnover and carbachol-stimulated PI turnover in normal animals as well as after inflammation. Inflammation resulted in increased baseline PI turnover in this region of the ipsilateral (76%) and contralateral (65%) dorsal horns. Carbachol increased PI turnover in this region in normal rats (55%) and following inflammation (ipsilateral: 46%, contralateral: 45%). The absolute magnitudes of these increases were 1.85, 2.71, and 2.51 nCi/mg, respectively. The results of this study demonstrate the involvement of PI turnover in neural mechanisms of persistent pain, and provide evidence for the involvement of cholinergic systems in this process. Because spinal cholinergic systems have been reported to be anti-nociceptive, the present results appear to reflect an upregulation of anti-nociceptive activity in response to inflammation. Thus, the spinal cholinergic system may be a regulatory site within the anti-nociceptive pathway, and may provide an attractive target for the development of new therapeutic agents.
Date: May 2002
Creator: Moore, Jack
Partner: UNT Libraries

Ultrafast Laser Sampling of a Plant Tissue and ion Conductivity Measurement for Investigation of Light Stress Generation Mechanisms

Description: In this study we applied ultra-short laser pulses on a biological sample (Arabidopsis), in order to cut it precisely in a square pattern and subsequently use it for studying stress generation mechanisms. For this purpose, we utilized femtosecond laser pulses at 100 fs pulse width and 80 MHz repetition rate. We took two processing parameters into consideration such as laser power, laser exposure time which is related to the stage speed. Therefore, we were able to find the laser optimum conditions for ablation of biological tissues. The mutant and wildtype (control) obtained from laser cutting with a size of 500 µm × 500 µm were directly transferred (in-situ with laser cutting) into a microfabricated chamber containing ~500 nanoliters deionized water for measuring ion conductivity. The ion conductivity is a signature of cell-death mechanisms caused by various stresses. A light with intensity of 100 µmol was exposed to the samples for 2 hours and 20 minutes as a source of stress. A quantitative electrical analysis with high accuracy was assured by utilizing a microchamber, which enables a measurement in nanoliter volume. We measured the impedance which is reciprocal of conductivity using a lock-in amplifier and a precise current source at frequency of 130 Hz. Initially high impedance of mutant sample tended to drop within 2 hours and finally approached the constant value which signified that the cell death mechanism was complete. However, the wildtype sample demonstrated approximately constant impedance (conductivity) during the experiment.
Date: August 2010
Creator: Abtahi, Seyed Ali
Partner: UNT Libraries