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Effects of Water Quality, Instream Toxicity, and Habitat Variability on Fish Assemblages in the Trinity River, Texas

Description: The Trinity River flows through the Dallas-Ft. Worth Metroplex in north central Texas where it receives effluents from numerous point sources including seven large regional wastewater treatment facilities. Historically, the Trinity River has been impacted by massive wastewater loadings which often constitute > 80% of the total river discharge during low flow periods. Normally, high mass loadings correspond to the summer months, compounding the effects of a naturally stressful period, characterized by high temperatures and low dissolved oxygen concentrations. Samples from 12 stations were collected quarterly over an 18 month period from the Trinity River and two tributaries. Water samples were analyzed for a variety of water quality variables, including metals, priority pollutants, pesticides, and general water quality parameters. Water samples were also tested for acute and subchronic effects with several test species. Fish were collected at each station and assemblages were characterized using traditional classification techniques and the Index of Biotic Integrity. In addition, sediment samples were assessed for toxic effects which could have adversely impacted fish recruitment and in situ biomonitoring experiments were performed. Quantitative habitat characterization analyses were performed to gain additional information that could possibly explains differences in fish assemblage structure related to habitat variability. Data were analyzed using regression, univariate, multivariate, and descriptive statistical techniques and new approaches for analyzing impact assessment data were discussed. Results indicated that the most substantial impacts on fish assemblages were confined to a segment of the river where a sequence of point sources, in close proximity to each other, were overloading the river's capacity to sufficiently dilute and/or detoxify the effluent. Data also indicated the presence of episodic toxicity from nonpoint sources. In addition, toxic effects in sediment samples and differences in habitat were detected and may have contributed to measured differences among fish assemblages in the Trinity River.
Date: December 1989
Creator: Arnold, Winfred R., 1960-

Effects of Water Source, Suspended Solids, and Acclimation on Biotransformation of 2 /4-Dichlorophenoxy Acetic Acid in Aquatic Systems

Description: In recent years there has been a great deal of scientific interest in processes that affect the fate of organic chemicals in the environment. one main reason for this increased interest is due to greater environmental concern over accidental or purposeful release of these chemicals into the environment by man. A major environmental concern is the increased use of pesticides over the last few years. In the thirty years prior to 1978 the use of pesticides has increased by a factor of forty (Ridgeway et al., 1978). Recently the use of herbicides has been increasing, but that of insecticides has stabilized (Willis, 1983). Detectable amounts of organic pesticides can be found in many areas of the biosphere. For toxic organic chemicals to be used safely, researchers must have a clear understanding of the fate and persistence of these chemicals when they are released into the environment. This understanding will also allow the development of new products that, when properly used, will not produce adverse effects to man or the environment (Weber, 1972). According to the Toxic Substance Control Act (TSCA) any new or expanded-use chemical that might be released into the environment must be tested for environmental hazard.
Date: August 1985
Creator: Moses, Christopher K. (Christopher Karam)

Effects of Web-based Instruction in High School Chemistry.

Description: The intent of this study is to identify correlations that might exist between Web-based instruction and higher assessment scores in secondary education. The study framework was held within the confines of a public high school chemistry classroom. Within this population there were students identified as gifted and talented (GT) as well as those without this designation. These two classifications were examined for statistically higher assessment scores using a two-tailed t-test. Results indicated that females outperformed males on pre- and post- instructional unit tests. All subgroups improved their logical-thinking skills and exhibited positive attitudes towards Web-based instruction. In general, Web-based instruction proved beneficial to improving classroom performance of all GT and non-GT groups as compared to traditional classroom instruction.
Access: This item is restricted to the UNT Community Members at a UNT Libraries Location.
Date: May 2003
Creator: Stratton, Eric W.

The Effects of Web-Based Learning Versus Traditional Instructor-Based Learning on Student Knowledge and Satisfaction Based on Student Learning Styles

Description: The purpose of this study was to compare the effects of Web-based learning (WBL) versus those of traditional instructor-based learning (IBL) on student knowledge and satisfaction based on student learning styles. Other goals were to determine if WBL is more effective for those with a particular learning style. The study examined a sample of undergraduate students who were enrolled in the college algebra offered as both oncampus instructor-based (traditional) and Web-based at the university of North Texas (UNT). A total of 36 Web-based students and 58 instructor-based students participated in this study. This study utilized a posttest-only intact group. The Kolb Learning Style Inventory (LSI) measured the learning styles of students. This study used learning methods (Web-based learning (WBL), instructor-based learning (IBL)), and learning styles (Diverger, Converger, Assimilator, and Accommodator) as independent variables. Student knowledge and student satisfaction was measured at the end of the course as independent variables. Based upon the results of the LSI, post-learning exam, and satisfaction a series of two-way analysis of variance (ANOVA 4x2) techniques and independent variable tests was used for each of the dependent variables, knowledge and satisfaction, based on a student's learning styles. The results revealed that students' learning styles were statistically significant for knowledge when learning on the Web versus instructor-led. In addition, the learning style was important factor for Web-based learning. The results indicated students with Assimilator and Converger as learning styles received better result with the Web-based learning method. Furthermore, this study found there is significant difference in student satisfaction based on learning on the Web versus instructor-led. The outcome of the study could be of particular interest in educational institutions; especially those that want to transfer some of their traditional courses onto the Web. The finding also has implications for training organizations as they seek efficient and effective ...
Access: This item is restricted to UNT Community Members. Login required if off-campus.
Date: December 2001
Creator: Manochehri, Naser

The Effects of Weight Loading and Repetitions, Frequency of Exercise, and Knowledge of Theoretical Principles of Weight Training on Changes in Muscular Strength

Description: The purpose of this study was to determine the effects of weight loadings and repetitions, frequency of exercise, and knowledge of theoretical principles of weight training on changes in muscular strength. Another purpose was to analyze these effects and determine implications for coaches, physical educators, physical therapists, and others interested in determining the optimum combination of the three variables for increasing muscular strength.
Date: January 1970
Creator: Henderson, Joe Mack

Effects of Whisker-Trimming on GABAA Receptors in S1 Cortex

Description: A number of studies have shown that sensory deprivation is associated with selective decreases in GABA, GAD, and GABA receptors, in deprived areas of visual and somatosensory cortex. Those studies focused on layer 4, a recipient of direct thalamocortical sensory input. However, supragranular layers 2/3 have been recently identified as a major locus of functional plasticity in sensory deprivation and long-term potentiation. To examine whether GABAA receptors in layers 2/3 are affected by sensory deprivation, rats had mystacial vibrissae in middle row C or rows ABDE trimmed for 6 weeks beginning in early adulthood. Layers 2/3 above the deprived and adjacent whisker barrels were located in tangential sections, using patterns of radial blood vessels as fiducial marks. In deprived whisker barrel columns, [3H]muscimol binding to GABAA receptors decreased by 12.8% ± 1.2 (P &lt; 0.001) in layers 2/3 and 11.4% ± 1.2 (P<0.001) in layer 4. Altered levels of GABAA α1 subunit (Fritschy et al., 1994) were indicated by reduced optical density of immunostaining, both in deprived layers 2/3 (6.4% ± 0.7; P&lt; 0.001) and in layer 4 (3.4% ± 1.0; P &lt; 0.005). Interestingly, Nissl staining density also decreased in deprived layers 2/3 (12.7% ± 1.8 P &lt; 0.001) and in 4 (6.0 ± 0.7 (P &lt; 0.001). The percent decreases were greater in layers 2/3 than in 4 for both GABAA α1 (P &lt; 0.05) and Nissl substance (P &lt; 0.005). The present results suggest that down-regulation in GABAA receptors may underlie the physiological signs of disinhibition observed in neurons of layer 2/3 and 4 in deprived whisker barrel columns.
Date: August 2004
Creator: Salazar, Eduardo

The Effects of Workshop Training and Coaching on the Acquisition and Generalization of Teaching Skills

Description: The purpose of this study was threefold: (a) to examine the separate effects of increased accuracy on multiple-choice/rank-order written tests and coaching on the teaching performance of participants; (b) to compare generalization across tasks produced by the workshop and coaching; and (c) to assess maintenance of teaching performance. Following baseline, two adults received a lecture on discrete trial teaching procedures. A written test measured verbal performance on workshop material periodically throughout this phase. During the next phase, each adult then experienced further training via in-situ coaching. A multiple baseline design across tasks was used during the coaching phase. Results of the workshop training package revealed an inverse relationship between the strongest verbal performance and strongest teaching performance skill areas. In addition, only with the introduction of the in-situ coaching package did teacher performance improve significantly across all behaviors. Child responding remained relatively constant throughout the study, regardless of teacher performance. Some generalization of teacher behavior was observed across tasks, but was extremely variable across both workshop and coaching conditions. After the cessation of coaching, teacher performance remained stable across maintenance phases and at a 6-week follow-up.
Date: December 2003
Creator: Almon, Holly C.

The Effects of Writing-to-learn Tasks on Achievement and Attitude in Mathematics

Description: The problem of this study was to determine the effects of implementing writing-to-learn tasks in mathematics instruction on fourth grade students' achievement and attitude toward mathematics. Also addressed in this study is whether or not achievement and attitude measures of female students and low achieving students are effected by the use of writing in mathematics.
Date: May 1994
Creator: Millican, Beverly Robinson

The Effects of Written Comment on Expository Composition

Description: This study was planned to investigate the effects of written comments on the expository compositions of eleventh-grade students using a cross section of ability groups. Data for combined groups and data for high-, middle-, and low-ability groups were used to determine whether one type of comment was more effective than another in improving the quantity and quality of student compositions and in improving student attitudes toward composition. Teachers may use the findings as a guide to what kinds of comments are most effective in reinforcing good writing skills and attitudes.
Date: June 1970
Creator: Gee, Thomas C., 1940-

Effects of X-Irradiation of Respiration in Frog Brain Tissue Slices Using the Oxygen Electrode Method

Description: The effects of X-irradiation at dosages of 40 r, 80 r, 160 r, 240 r, 320 r, 400 r, 800 r, 4 Kr, 8 Kr, and 16 Kr on the oxygen uptake of frog brain (Rana pipiens) tissue slices were studied. A membrane-covered oxygen electrode method was used to measure the respiratory rate. Continuous recordings were made before, during, and following X-irradiation in all of the test experiments. X-irradiation was delivered from a G. E. beryllium window X-ray unit at 120 KVP, 5 ma with a 1/4 mm Al filter.
Date: August 1971
Creator: Lin, Chen-hsiung

Effects of X-irradiation on Potassium Flux in Isolated Nerves

Description: The purpose of this study, therefore, was threefold in nature: (1) to determine the effects of x-irradiation on the influx and efflux of potassium in compound nerve fibers (2) to attempt to relate the radiation-induced changes in electrical activity with potassium flux and (3) to use the information obtained to gain insight into the possible cellular site (s) of radiation insult to compound nerves.
Date: August 1966
Creator: Ramsey, Christian Norman

Effects of X-Irradiation on Water and Ion Flux in Isolated Roots

Description: Due to the relatively small amount of work concerning radiation, it was thought feasible to use ionizing radiation as a tool to study the relationship between water and salt flux in isolated root systems. Moreover, the more quantitative potometric method lends itself well to such a study, since the two processes can be followed simultaneously. the aims of this study, therefore, were 1) to determine effects of X-irradiation on water, calcium and potassium flux in excised onion roots; 2) to determine the dose levels required for producing permeability changes; 3) to investigate the nature of radiation damage to root systems; and 4) to attempt to shed light on the relation between water transport and ion movement in root systems.
Date: January 1967
Creator: Wall, Malcolm J.

Effects on Survival, Reproduction and Growth of Ceriodaphnia dubia following Single Episodic Exposure to Copper or Cadmium

Description: Effects of episodic exposures have gained attention as the regulatory focus of the Clean Water Act has shifted away from continuous-flow effluents. Standardized laboratory toxicity tests require that exposure be held constant. However, this approach may not accurately predict organism responses in the field following episodic exposures such as those associated with rain-driven runoff events or accidental pollutant discharge. Using a modified version of the 7-day short-term chronic test recommended by the US Environmental Protection Agency, Ceriodaphnia dubia were exposed to copper or cadmium for durations ranging from 1 minute to 24 hours. In addition, adult reproductive recovery and effects on second generation individuals was assessed following select copper exposures. Finally, cadmium exposures were compared in reconstituted hard water (RHW) and municipal treated wastewater effluent (TWE). Following exposure, organisms were transferred to clean RHW or TWE and maintained for the remainder of the test. No- and lowest observed effect concentrations (NO- and LOECs) increased logarithmically with respect to logarithmic decreases in duration regardless of metal, endpoint or water type. Effective concentrations of cadmium however, were usually higher than those of copper, especially in TWE. LOECs for C. dubia survival following 24-hour and 5-minute exposures to copper were 116 and 417 µg/L, respectively. LOECs for fecundity were 58 and 374 µg/L, respectively. Neonate production of first generation adult C. dubia appeared to recover from pulsed copper exposure upon examination of individual broods. Cumulative mean neonate production however, showed almost no signs of recovery at exposure durations ≥3 hours. Pulse exposure to copper also resulted in diminished fecundity of unexposed second generation individuals. Such effects were pronounced following parental exposure for 24 hours but lacking after parental exposures ≤3 hours. LOECs for C. dubia survival following 24-hour and 5-minute exposures to cadmium in RHW were 44 and 9000 µg/L, respectively. LOECs for ...
Date: August 2005
Creator: Turner, Philip K.

Efficacy in Texas Charter Schools Compared to Traditional Public Schools

Description: The need to spur innovation and improve student performance initiated the formation of, under different legislative acts, charter schools that include variations of traditional public schools. With the enthusiasm and level of investment going into the formation of charter schools, it is necessary to explore whether these schools have achieved their objectives. This study explored whether Texas open enrollment charter schools perform bettered compared to Texas public schools. The study applied a causal comparative quantitative research design. School data on graduation and dropout rates, college preparation, attendance rates, and overall performance were analyzed quantitatively. Student achievement data available for statistical analysis includes student performance on the Texas Assessment of Knowledge and Skills (TAKS) state assessment from 2007 to 2011. Data analysis for race, special programs, at risk, economically disadvantaged, and limited English proficiency was incorporated. Descriptive statistics and analysis of variance techniques were included in the data analysis. The analysis extended to post hoc tests to determine variables that caused variation. The study found Texas open-enrollment charter schools had more African American students but fewer Whites compared to public schools. Students in public schools performed better than those in charter schools, and Whites yielded the best performance. Charter schools had high dropout rates, low attendance, and low graduation rates, while public schools had low dropout rates, high attendance, and high graduation rates. Finally, public schools had more students ready for college than charter schools.
Date: August 2015
Creator: Keller, Karlyn

The Efficacy of Equine Assisted Group Counseling with At-Risk Children and Adolescents

Description: The purpose of this study was to determine the efficacy of equine assisted group counseling as compared to in-school curriculum group guidance/counseling. Research examined externalizing, internalizing, maladaptive, and adaptive behaviors of elementary and middle school students who were considered at-risk of academic or social failure. Two types of behavior instruments, the Behavioral Assessment System for Children (BASC)-Self-Rating, Parent-Rating, and Teacher-Rating Scales; and the Animal Assisted Therapy-Psychosocial Session Form (AAT-PSF), were used in a pretest-posttest comparison group quasi experimental design. Results of the paired sample t-test analysis of the BASC Self-Report indicated that the equine assisted counseling group showed statistically significant improvement in five behavior areas, and the in-school curriculum group guidance/counseling group showed statistically significant improvement in four areas, with only one behavior area the same as the equine assisted counseling group. Results of the paired sample t-test analysis of the BASC Parent-Report indicated that the equine assisted counseling group showed statistically significant improvement in twelve behavior areas, whereas the in-school curriculum group guidance/counseling showed statistically significant improvement in only one behavior area. Results of the paired sample t-test analysis of the BASC Teacher-Report indicated that the equine assisted counseling group showed no statistically significant improvement; however the in-school curriculum group guidance/counseling group showed statistically significant improvement in one area. An ANCOVA comparison of equine assisted counseling group verses in-school curriculum guidance/counseling group using the BASC Self, Parent, and Teacher-Reports indicated that the equine assisted counseling group showed statistically significant improvement in seven behavior areas that the in-school curriculum guidance/counseling group did not. Results of the repeated measures ANOVA of the AAT-PSF (equine assisted counseling group only) showed statistically significant improvement in all 3-scale scores: 1) overall total behaviors; 2) increased positive behaviors; and 3) decreased negative behaviors.
Date: December 2006
Creator: Trotter, Kay Sudekum

The Efficacy of Filial Therapy with Families with Chronically Ill Children

Description: This study was designed to determine the effectiveness of Filial Therapy as a method of intervention with families with chronically ill children. Filial Therapy is an intervention that focuses on strengthening and enhancing the parent-child relationship. Parents are trained to become the agents of change for their children's behaviors by utilizing basic child-centered play therapy skills in weekly play sessions. The purpose of this study was to a) determine the effectiveness in decreasing parental stress, b) determine the effectiveness in increasing parental acceptance, and c) determine the effectiveness in decreasing problematic behaviors in the chronically ill child as assessed by their parents.
Date: May 1997
Creator: Tew, Kristi L. (Kristi Lee)

The Efficacy of Intensive Individual Play Therapy for Children Diagnosed with Insulin-Dependent Diabetes Mellitus

Description: This study was design to determine the efficacy of intensive individual play therapy as a method of intervention for children diagnosed with insulin-dependent diabetes mellitus. The purpose of this study was designed to study the effectiveness of an intensive play therapy intervention in: a) reducing symptoms of childhood depression in children with IDDM; b) reducing symptoms of anxiety in children with IDDM; c) reducing the overall behavior difficulties in children with IDDM; d) increasing healthy adjustment in children with IDDM; e) increasing diabetic's children's adherence to their diabetic regime; and f) impacting these emotional and behavioral symptoms over time. The 15 children in the experimental group received 12, daily play therapy sessions while attending a summer camp for children with diabetes. The control group, consisting of 15 children who attended the diabetic summer camp, received no play therapy. Children and parents in both groups completed pretest, post-test and three-month follow-up data, consisting of: the Children's Depression Inventory, the Revised Children's Manifest Anxiety Scale, the Filial Problems Checklist and the Diabetes Adaptation Scale. Analysis of covariance revealed that the children in the experimental group significantly improved their adaptation to their diabetes following intensive play therapy as reflected by the Diabetes Adaptation Scale. No other hypothesis were retained, although statistical trends noted increased improvement in the experimental group in the areas of behavior difficulties and adherence behavior. Possible explanations for these results include a lack of symptoms reported at the time of pretesting and the validity of these instruments for a chronically ill population. The results of this study indicate that intensive play therapy may be an effective intervention for children diagnosed with IDDM. Qualitative observations and progress noted in therapy reveal that young children with IDDM have the capability to address and resolve issues of anxiety, depression and other emotional issues ...
Date: August 2000
Creator: Jones, Elizabeth Murphy

Efficacy of Juvenile Offender Assessments: Utilization of Recommendations, Measurement Constructs, and Risk Factors

Description: The purpose of this study was to explore the efficacy of juvenile offender assessments. Data from 104 juvenile offender assessments were analyzed and followed up with placement, subsequent offending, and outcome data from the juvenile and adult systems. Constructs consistently assessed included intellectual functioning, academic achievement, and personality functioning; however, under-diagnosis of intellectual deficits, learning disabilities, and personality disorders was found. Results indicated the assessment of family functioning, substance use, and social functioning should be included in comprehensive assessments, as they may result in alternative placement and treatment options of benefit to the juvenile offender. A juvenile offender typology proposed by DiCataldo and Grisso (1995) was successfully utilized and proved predictive of recidivism, future harm to others, and outcome.
Date: August 2002
Creator: Van Drie, Barbara G

Efficacy of neurofeedback for children with histories of abuse and neglect: Pilot study and meta-analytic comparison to other treatments.

Description: This two-part study investigates the effectiveness of neurofeedback training for reducing behavioral problems commonly observed in abused/neglected children, and compares its efficacy to other treatment interventions with this population. Neuro-developmental sequelae of early relationship trauma are explored as an etiological framework for understanding disturbed affect-regulation, which appears central to the behavioral and emotional difficulties commonly experienced by this pediatric population. It is suggested that neurofeedback teaches children to self-regulate brain rhythmicity mechanisms, which in turn affects global improvements in behavior and mood. The pilot study utilizes records of 20 children removed from their biological homes by Child Protective Services. Children were assessed prior to treatment using the Child Behavior Checklist (CBCL) and the Test of Variables of Attention (TOVA), and again after 30 sessions of individualized, qEEG-guided neurofeedback training. A t-test analysis of pre- and post-scores was computed, and indicated significant improvements following treatment. A meta-analysis of existing literature on treatment interventions with abused/neglected children provides individual and aggregate effect sizes for 33 outcome studies with this clinical population, and contextualizes the results of the present pilot study within other empirically validated treatment modalities. Establishment of an overall effect size for treatment for this pediatric population provides a needed method of comparing research results across studies when control groups may not be ethical or feasible.
Date: August 2008
Creator: Huang-Storms, Lark

The efficacy of self-administered systematic desensitization

Description: The purpose of this study was to test the therapeutic usefulness of a completely self-administered, behavior-therapy technique: systematic desensitization. The method involved the comparison of behavior change following the treatment of two groups of subjects. One group received the actual systematic-desensitization procedure, while the other underwent a similar but theoretically ineffective treatment termed attention-placebo.
Date: May 1977
Creator: Horowitz, Neil D.