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Dark Houses: Navigating Space and Negotiating Silence in the Novels of Faulkner, Warren and Morrison (open access)

Dark Houses: Navigating Space and Negotiating Silence in the Novels of Faulkner, Warren and Morrison

Poe's "The Fall of the House of Usher," as early as 1839, reveals an uneasiness about the space of the house. Most literary scholars accept that this anxiety exists and causes some tension, since it seems antithetical to another dominant motif, that of the power of place and the home as sanctuary. My critical persona, like Poe's narrator in "The House of Usher," looks into a dark, silent tarn and shudders to see in it not only the reflection of the House of Usher, but perhaps the whole of what is "Southern" in Southern Literature. Many characters who inhabit the worlds of Southern stories also inhabit houses that, like the House of Usher, are built on the faulty foundation of an ideological system that divides the world into inside(r)/outside(r) and along numerous other binary lines. The task of constructing the self in spaces that house such ideologies poses a challenge to the characters in the works under consideration in this study, and their success in doing so is dependant on their ability to speak authentically in the language of silence and to dwell instead of to just inhabit interior spaces. In my reading of Faulkner and Warren, this ideology of …
Date: December 2000
Creator: Berger, Aimee E.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Effects of Biofeedback on Task Performance (open access)

The Effects of Biofeedback on Task Performance

This experiment attempted to study the effectiveness of biofeedback training on an individual's peak performance while performing a stress-provoking task. In a between subjects design 30 individual college students were divided into 2 groups. One group received auditory biofeedback and relaxation training, and the other group received no training. Both groups met the researcher for 1 hour a week for seven weeks. During each session the participant completed a ten-minute Competition and Coaction (C & C) computer software program (Shea, 1992). The biofeedback equipment recorded the physiological state of each of the participants while he/she performed the C & C task. Both groups' physiological values and C & C scores were compared using the SPSS software. The biofeedback group had statistically lower stress values than the non-biofeedback group (Schwartz, 1995). There was no statistical difference between the 2 groups' C & C scores. The STAI Y-1 and Y-2 anxiety inventories were given to each of the participants at the 1st and 7th session to examine the anxiety differences between the 2 groups. There were no statistical differences between the 2 groups' STAI scores. This study's findings show that individuals can be taught to lower their stress response while performing a …
Date: December 2000
Creator: Bruce, Kurt
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Preparation and Characterization of a Treated Montmorillonite Clay and Epoxy Nanocomposite (open access)

Preparation and Characterization of a Treated Montmorillonite Clay and Epoxy Nanocomposite

Montmorillonite reinforced polymers are a new development in the area of nanocomposite materials. Since reinforcement of epoxy is important to the development of high strength adhesives and composite matrices, the introduction of montmorillonite to epoxy is of interest. Compositional effects on epoxy reactivity, on molecular relaxation, and on mechanical properties were investigated. Change in reactivity was determined by Differential Scanning Calorimetry. Tensile properties at room temperature indicated improved modulus and retention of strength of the epoxy matrix but a decreased elongation to failure. Depression of dry nanocomposite glass transition was observed for nanocomposites beyond 5% by weight montmorillonite. Samples that were saturated with water showed lower moduli due to the epoxy matrix. The greatest moisture absorption rate was found at 7%, the least at 3%.
Date: December 2000
Creator: Butzloff, Peter Robert
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Unexpected Unexpected Utilities: A Comparative Case-Study Analysis of Women and Revolutions (open access)

Unexpected Unexpected Utilities: A Comparative Case-Study Analysis of Women and Revolutions

Women have been part of modern revolutions since the American Revolution against Great Britain. Most descriptions and analyses of revolution relegate women to a supporting role, or make no mention of women's involvement at all. This work differs from prior efforts in that it will explore one possible explanation for the successes of three revolutions based upon the levels of women's support for those revolutions. An analysis of the three cases (Ireland, Russia, and Nicaragua) suggests a series of hypotheses about women's participation in revolution and its importance to revolutions' success.
Date: December 2000
Creator: Casey, Walter Thomas
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Theoretical STM signatures and transport properties of native defects in carbon nanotubes (open access)

Theoretical STM signatures and transport properties of native defects in carbon nanotubes

Article on theoretical STM signatures and transport properties of native defects in carbon nanotubes.
Date: May 15, 2000
Creator: Orlikowski, Daniel; Buongiorno Nardelli, Marco; Bernholc, Jerry & Roland, Christopher
Object Type: Article
System: The UNT Digital Library
Research Summary: September 18, 2000 (open access)

Research Summary: September 18, 2000

Research summary looking at the students of the Texas Academy of Mathematics and Science. Information on demographics, student satisfaction, computer use, regression analyses for admission variables, DAT data analyses, GPA-based group comparison, group differences for admission variables, and descriptive data is included.
Date: September 18, 2000
Creator: Texas Academy of Mathematics and Science
Object Type: Report
System: The UNT Digital Library
Establishment and Competitive Ability of Nelumbo Lutea in Relation to Myriophyllum Spicatum (open access)

Establishment and Competitive Ability of Nelumbo Lutea in Relation to Myriophyllum Spicatum

Limitations from reduced light and increasing water depth on Nelumbo lutea seedlings were determined in tank experiments. Survival was high in all tested light levels. Total biomass increased significantly with increasing light. Biomass allocation shifted significantly to root production between 3 and 6 weeks in the 10 and 24% levels. Survival decreased with increasing planting depth, and biomass of survivors reduced significantly between 0.5, 1.0, and 1.5 m depths. Nelumbo lutea and Myriophyllum spicatum populations were monitored for one season in a 0.7 ha pond to track changes in species dominance. Myriophyllum spicatum dominated early, and N. lutea dominated from July through October, suppressing M. spicatum at all depths. Competitive interactions between N. lutea and M. spicatum were investigated for two seasons in a container experiment situated within a pond. Where established, N. lutea dominated in the presence of M. spicatum. However, N. lutea could not be established in depths greater than 1 meter.
Date: December 2000
Creator: Snow, Joe R.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Comparative Analysis of Intensive Filial Therapy with Intensive Individual Play Therapy and Intensive Sibling Group Play Therapy with Child Witnesses of Domestic Violence (open access)

Comparative Analysis of Intensive Filial Therapy with Intensive Individual Play Therapy and Intensive Sibling Group Play Therapy with Child Witnesses of Domestic Violence

The purpose of this study was to determine the effectiveness of Intensive Filial Therapy in: (a) improving the self-concept of child witnesses of domestic violence; (b) reducing internalizing behavior problems, such as withdrawal, somatic complaints, anxiety and depression, of child witnesses of domestic violence; (c) reducing externalizing behavior problems, such as aggression and delinquency, of child witnesses of domestic violence; (d) reducing overall behavior problems of child witnesses of domestic violence; and (e) increasing communication of empathy between mothers and child witnesses of domestic violence. A second objective of this study was to compare the effectiveness of Intensive Filial Therapy with Intensive Individual Play Therapy and Intensive Sibling Group Play Therapy with child witnesses of domestic violence. The experimental group consisted of 11 child witnesses of domestic violence whose mothers received 12 Intensive Filial Therapy training sessions within a three week period and had 12 mother-child play sessions. The Intensive Individual Play Therapy comparison group, consisting of 11 child witnesses, and the non-treatment control group, consisting of 11 child witnesses, were utilized from the Kot (1995) study. The Intensive Sibling Group Play Therapy comparison group was utilized from the Tyndall-Lind (1999) study. Children in all studies completed the Joseph Preschool …
Date: December 2000
Creator: Smith, Nancy Renfer
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Effects of a Play Therapy Intervention Conducted by Trained High School Students on the Behavior of Maladjusted Young Children: Implications for School Counselors (open access)

The Effects of a Play Therapy Intervention Conducted by Trained High School Students on the Behavior of Maladjusted Young Children: Implications for School Counselors

This research study investigated the effectiveness of a child-centered play therapy intervention conducted by trained high school students on the behavior of preschool and kindergarten children with adjustment difficulties. Specifically, this research determined if play sessions conducted by high school students trained in child-centered play therapy skills and procedures facilitated change in the children's behaviors. The experimental group children (N=14) each received 20 weekly individual play sessions from a high school student enrolled in a Peer Assistance and Leadership class. The high school students were randomly paired with a referred child. The high school students completed 7 one-hour training sessions in child-centered play therapy procedures and skills prior to beginning the weekly, supervised play sessions. The control group (N=12) received no treatment during the study. Pre and post data were collected from parents who completed the Child Behavior Checklist (CBCL) and teachers who completed the Early Childhood Behavior Scale (ECBS). Multivariate analyses of variance of gained scored revealed statistical significance in 2 of the 4 hypotheses. Specifically, the children in the experimental group showed significant decreases in internalizing behaviors (p = .025) and total behaviors (p = .025) on the CBCL. Although not in the statistically significant range, positive trends …
Date: December 2000
Creator: Rhine, Tammy J.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
A Behavioral Economic Analysis of the Demand for Money in Humans (open access)

A Behavioral Economic Analysis of the Demand for Money in Humans

This study investigated the effects of unit price structure, unit price descriptions, and unit price sequence on the demand for money in humans. Six groups of 3 participants solved multiplication problems in exchange for money under various unit prices. Consumption of money decreased as the unit price increased across all conditions. However, the data also showed that: (a) fixed price structures produced slightly more elastic demand than did variable price structures, (b) price descriptions produced more elastic demand under variable price structures but had little or no effect under fixed price structures, and (c) the alternate sequence used with fixed price structures produced slightly more elastic demand.
Date: December 2000
Creator: Reyes, Jorge R.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Epoxy + Liquid Crystalline Epoxy Coreacted Networks (open access)

Epoxy + Liquid Crystalline Epoxy Coreacted Networks

Molecular reinforcement through in-situ polymerization of liquid crystalline epoxies (LCEs) and a non-liquid crystalline epoxy has been investigated. Three LCEs: diglycidyl ether of 4,4'-dihydroxybiphenol (DGE-DHBP) and digylcidyl ether of 4-hydroxyphenyl-4"-hydroxybiphenyl-4'-carboxylate (DGE-HHC), were synthesized and blended with diglycidyl ether of bisphenol F (DGEBP-F) and subsequently cured with anhydride and amine curing agents. Curing kinetics were determined using differential scanning calorimetry (DSC). Parameters for autocatalytic curing kinetics of both pure monomers and blended systems were determined. The extent of cure for both monomers was monitored by using Fourier transform infrared spectroscopy (FT-IR). The glass transitions were evaluated as a function of composition using DSC and dynamic mechanical analysis (DMA). The results show that the LC constituent affects the curing kinetics of the epoxy resin and that the systems are highly miscible. The effects of molecular reinforcement of DGEBP-F by DGE-DHBP and DGE-HHC were investigated. The concentration of the liquid crystalline moiety affects mechanical properties. Tensile, impact and fracture toughness tests results are evaluated. Scanning electron microscopy of the fracture surfaces shows changes in failure mechanisms compared to the pure components. Results indicate that mechanical properties of the blended samples are improved already at low concentration by weight of the LCE added into …
Date: December 2000
Creator: Punchaipetch, Prakaipetch
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Four Major Education GI Bills: A Historical Study of the Shifting National Purposes and Accompanying Changes in Economic Value to Veterans (open access)

The Four Major Education GI Bills: A Historical Study of the Shifting National Purposes and Accompanying Changes in Economic Value to Veterans

Benefits for soldiers follow the formation of ancient and present day armies raised for the purpose of extending the national or state will. Veterans' benefits for defenders of the U.S. emerged during the American colonial period. College benefits began after WWII with the GI Bill of Rights. This study examines the variations in purpose for nationally established educational benefits for veterans and the singular value to the veterans of these 5educational benefits. The study begins with an overview of the history of veterans' benefits. Primary emphasis is then placed on the educational portion of the World War II Servicemen's Readjustment Act and the current educational benefit, the Montgomery GI Bill. As the purpose of awarding educational benefits changed from World War II to the latest U.S. war, the Gulf War of 1990-1991, the economic value to the individual veteran also changed. The WWII GI Bill featured an educational provision intended to keep returning veterans out of the changing economy whereas current GI Bills is intended as a recruiting incentive for an all-volunteer force. Correspondingly, the economic value to the individual veteran has changed. Data supporting this study were extracted from historical documents in primary and secondary scholarly studies and writings, …
Date: December 2000
Creator: Spaulding, Donald James
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Relationship Among Teacher Expectations, Teacher Attitudes Toward the TAAS, and Student Achievement (open access)

The Relationship Among Teacher Expectations, Teacher Attitudes Toward the TAAS, and Student Achievement

Accountability is a major issue in education and in Texas, the TAAS test is used to indicate performance of students, teachers, campuses, and districts. The stakes are high for students, as performance on this test has determined whether they progress to another grade and whether they will receive a diploma. Most research studies focus on relationships between the teacher and individual students or groups of students, but not classrooms. Expectations and high stakes testing are central within the educational process, and their relationship on student achievement should be investigated, especially since no studies on teacher attitudes toward the TAAS test have been found. This correlational study measured teacher attitudes toward the TAAS and teacher expectations for students through data collected from a survey. Student achievement information was collected from averaged Texas Learning Index scores for students by classroom over a two year period. The sample consisted of 22 4th, 8th, and 10th grade reading and/or math teachers who had taught in the same Texas mid-sized, rural school district for at least two years. Frequency, percent, mean, and standard deviation were used to analyze the responses on the survey. A median score distinguished between high/low expectations and between positive/negative attitudes toward …
Date: December 2000
Creator: Sweatt, Shelley S.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Southwest Retort, Volume 52, Number 7, March 2000 (open access)

Southwest Retort, Volume 52, Number 7, March 2000

This publication of the Dallas-Fort Worth Section of the American Chemical Society includes information about research, prominent scientist, organizational business, and various other stories of interest to the community.
Date: March 2000
Creator: American Chemical Society. Dallas/Fort Worth Section.
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
Psychometric Development of the Adaptive Leadership Competency Profile (open access)

Psychometric Development of the Adaptive Leadership Competency Profile

This study documented the psychometric development of the Adaptive Leadership Competency Profile (ALCP). The ALCP was derived from a qualitative database from the National Science Foundation project (NSF 9422368) and the academic body of literature. Test items were operationalized, and subject matter experts validated 11 macro-leadership competencies and 65 items. Rasch rating scale measurement models were applied to answer the following questions: (a) How well do the respective items of the ALCP fit the Rasch rating scale measurement model for the 11 scales of the ACLP? (b) How well do the person's abilities fit the Rasch rating scale measurement model, using the 11 scales of the ALCP? (c) What are the item separation and reliability coefficients for the 11 ALCP scales? (d) What are the person separation and reliability coefficients for the 11 ALCP scales? This study also sought to discern whether the ALCP could predict leader effectiveness as measured by the likelihood ratio index and frequency of correct predictions indices. The WINSTEPS and LIMDEP programs were used to obtain Rasch calibrations and probit estimates, respectively. The ALCP profiles the frequency and intensity of leadership behavior. Composite measures were calculated and used to predict leadership effectiveness. Results from this study …
Date: December 2000
Creator: Sherron, Charles T.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Haiku Seasons (open access)

Haiku Seasons

Haiku Seasons is a choral work that uses several haiku to portray moments in nature. Spread throughout the performance space, four choirs (SATB, 3/part) depict larger parts of the pastoral scene (i.e., mountains, the moon, etc.). Soloists depart from the choirs in order to perform solo, duo, trio, and quartet passages, which take place throughout the work. If enough singers are available, individual soloists may be used. The soloist groups display the more intimate moments of the scenes (i.e., sparrows, a blade of grass, etc.). The intent of Haiku Seasons is to create an image of nature isolated from human interaction. Thus, the image is a pastoral setting with many independent parts all coexisting in a relatively silent world. I combine aspects of tonality, time, space, and silence to create this image.
Date: December 2000
Creator: Smith, Steven Lyle
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Assessment of the Effects of Interpersonal Openness and Coping Resources on the Psychological Sequelae of Traumatic Victimization (open access)

Assessment of the Effects of Interpersonal Openness and Coping Resources on the Psychological Sequelae of Traumatic Victimization

The present study tested a model addressing whether interpersonal Openness and interpersonal and intrapersonal Coping Resources mediated the relationship between interpersonal Victimization and the Psychological Symptoms women experience as a result of these traumas. Victimization indicators (physical violence, sexual assault, psychological abuse, and revictimization), Coping indicators (optimism, self-esteem, private self-consciousness, social network and therapy), Openness indicators (self-silencing, communal orientation, trust, self-monitoring, and network orientation), and Psychological Symptoms indicators (global distress, dissociation, and suicidal ideation) were examined separately for African American (n = 245), Euro-American (n = 185), and Mexican American (n = 202) women. Structural Equation Modeling revealed that for African American and Euro-American women, Openness partially mediated the victimization-distress relationship. The model for Mexican Americans was the most complex with Openness and intrapersonal Coping fully mediating the psychological effects of victimization. Approximately 50% of the variance in psychological symptoms resulting from victimization was predicted by this model for African American and Euro-American women; over 80% of the variance was predicted for Mexican Americans. Thus, the importance of Openness to relationships in alleviating the psychological sequelae following interpersonal victimization was underscored by the results. Similarities and differences between these models are discussed. Implications of the results for future research and …
Date: December 2000
Creator: Sedillo, Diane Marie
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Concurrent Validity of the Wide Range Assessment of Memory and Learning and the Woodcock-Johnson Tests of Cognitive Ability-Revised with a Neurologically Compromised Pediatric Population (open access)

Concurrent Validity of the Wide Range Assessment of Memory and Learning and the Woodcock-Johnson Tests of Cognitive Ability-Revised with a Neurologically Compromised Pediatric Population

The Wide Range Assessment of Memory and Learning (WRAML) is a relatively new instrument used in the assessment of memory in children. The purpose of this study was to examine the validity of the WRAML by comparing the performance of children on both the WRAML and the Woodcock-Johnson Tests of Cognitive Ability- Revised (WJTCA-R). Subjects for the study were children in treatment for a brain tumor at a regional children's medical center. Fifty children participated in the study ranging from ages 6 to 17. A multiple regression analysis was conducted to determine which of four selected clusters from the WJTCA-R would have the highest correlation with the Verbal Memory Index (VERI) from the WRAML. The Short-Term Memory (GSM) cluster had the highest correlation ( r = .82) as predicted. A Pearson's product-moment correlational analysis was conducted between the Visual Processing (GV) cluster from the WJTCA-R and the Visual Memory Index (VISI) from the WRAML. GV was found to have a high positive correlation ( r = .63) with VISI. A similar analysis was conducted between the Long-Term Retrieval (GLR) cluster from the WJTCA-R and the Learning Index (LRNI) from the WRAML. GLR was found to have a high positive correlation …
Date: December 2000
Creator: Rochelle, Gary B.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Dynamic Grid-Based Data Distribution Management in Large Scale Distributed Simulations (open access)

Dynamic Grid-Based Data Distribution Management in Large Scale Distributed Simulations

Distributed simulation is an enabling concept to support the networked interaction of models and real world elements that are geographically distributed. This technology has brought a new set of challenging problems to solve, such as Data Distribution Management (DDM). The aim of DDM is to limit and control the volume of the data exchanged during a distributed simulation, and reduce the processing requirements of the simulation hosts by relaying events and state information only to those applications that require them. In this thesis, we propose a new DDM scheme, which we refer to as dynamic grid-based DDM. A lightweight UNT-RTI has been developed and implemented to investigate the performance of our DDM scheme. Our results clearly indicate that our scheme is scalable and it significantly reduces both the number of multicast groups used, and the message overhead, when compared to previous grid-based allocation schemes using large-scale and real-world scenarios.
Date: December 2000
Creator: Roy, Amber Joyce
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Synthesis and characterization of molecules for electron transfer research. (open access)

Synthesis and characterization of molecules for electron transfer research.

Dimethoxynaphthalene (donor) and quinone (acceptor) have been chosen as a suitable redox pair and are bonded to either permethylated silane chains or corresponding permethylated alkyl chains to form Acceptor-(Bridge)-Donor molecules. The idea that the s-delocalization phenomenon of silane chains may greatly facilitate ET reactions will be tested. The starting material for the donor precursor, 4-(1,4-dimethoxynaphthyl)bromocyclohexane, was 1,4-naphthoquinone. After methylation and bromination, the Grignard reagent of the resulting bromide was reacted with cyclohexanedione, mono ethylene ketal. The resulting alcohol was changed to the donor precursor through the following functional group transformation steps: dehydration, hydrogenation, deketalization and bromination. 1,4-Dibenzyloxybromobenzene, the precursor for the acceptor, was synthesized from 1,4-hydroquinone through bromination and benzylation. The connection of the two precursors and either permethylated silane chains or permethylated alkyl chains will give the final target molecules for ET research. Progress on this is included.
Date: December 2000
Creator: Xiao, Wu
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Three Voices for voices, woodwind, percussion, and string instruments (open access)

Three Voices for voices, woodwind, percussion, and string instruments

Composed for soprano, tenor, and baritone voices, woodwind, percussion, and string instruments, Three Voices is a polyglotic work that includes German, Chinese, and Spanish texts. The texts are chosen from Brecht Bertolt's Das Schiff, Po Chu I's Lang T'ao Sha, and Frederico Garcia Lorcá's Mar. Significant features of the piece are 1) application of Chinese operatic singing methods to vocal material in the sections that use Chinese text, 2) use of western instruments to emulate the sound of certain Chinese instruments, and 3) employment of Sprechstimme and dramatically inflected speech to create theatrical effects and highlight the sections that use German and Spanish texts.
Date: December 2000
Creator: Wu, Man-Mei
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Southwest Retort, Volume 52, Number 5, January 2000 (open access)

Southwest Retort, Volume 52, Number 5, January 2000

This publication of the Dallas-Fort Worth Section of the American Chemical Society includes information about research, prominent scientist, organizational business, and various other stories of interest to the community.
Date: January 2000
Creator: American Chemical Society. Dallas/Fort Worth Section.
Object Type: Journal/Magazine/Newsletter
System: The UNT Digital Library
Training family therapists to work with families with young children: Current practices in accredited family therapy programs and recommendations for the future (open access)

Training family therapists to work with families with young children: Current practices in accredited family therapy programs and recommendations for the future

This study examined how current family counseling/therapy programs train students to work with families with young children and made recommendations for training in this area based on recommendations of child and family therapy experts and the research and clinical literature. These recommendations explored what knowledge and skills all students should acquire versus students who want to specialize with this population. Changes to accreditation standards were also proposed as well as a description of resources to support changes in program curricula. Current training was measured by examining curricula from master's level marriage and family counseling/therapy programs accredited by the Commission on Accreditation for Marriage and Family Therapy Education (COAMFTE) and the Council for Accreditation of Counseling and Related Education Programs (CACREP) and master's level social work programs with a family-related concentration accredited by the Council on Social Work Education Commission on Accreditation (CSWE), the accreditation standards from these three organizations, course syllabi from the COAMFTE and CACREP programs, and surveys of COAMFTE and CACREP program directors (60% response rate). Recommendations for training were obtained through a qualitative analysis of quotations from the literature concerning training and through interviews of child and family therapy experts (65% response rate). The results revealed the …
Date: December 2000
Creator: Crane, Jodi M.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Assessment of the Efficacy of a Constructed Wetland to Reduce or Remove Wastewater Effluent Estrogenicity and Toxicity Using Biomarkers in Male Fathead Minnows (Pimephales Promelas Rafinesque, 1820) (open access)

Assessment of the Efficacy of a Constructed Wetland to Reduce or Remove Wastewater Effluent Estrogenicity and Toxicity Using Biomarkers in Male Fathead Minnows (Pimephales Promelas Rafinesque, 1820)

Vitellogenin in Pimephales promelas was used to assess estrogenicity of a local municipal effluent. Vitellogenin induction in male P. promelas increased in frequency and magnitude with increased exposure duration and was greater ("=0.05) than controls after 2 and 3 weeks of exposure. The level of vitellogenesis induced by effluent exposure was high compared to similar studies. A spring season evaluation followed. Biomarkers in P. promelas were used to assess the efficacy of a treatment wetland to remove toxicity and estrogenicity in final treated wastewater effluent. Comparisons were made with an effluent dominated stream and laboratory controls. Vitellogenin, GSIs (gonado-somatic indices), HSIs (hepato-somatic indices) and secondary sexual characteristics were biomarkers used in P. promelas models to assess aqueous estrogenicity. Biological indicators used to assess general fish health included hematocrit and condition factors. The estrogenic nature of the effluent was screened, concurrent with fish exposure, with GC/MS analysis for target estrogenic compounds including: 17-b estradiol, estrone, ethynylestradiol, Bisphenol A, nonylphenolic compounds, phthalates, and DDT. Plasma vitellogenin measured in P. promelas was significantly elevated (p < 0.0001) at the inflow site of the wetland and stream sites. GSIs for these exposures were less (a=0.001) at the wetland inflow site. At wetland sites closest …
Date: December 2000
Creator: Hemming, Jon M.
Object Type: Thesis or Dissertation
System: The UNT Digital Library