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Effects of Triclosan, Triclocarban, and Caffeine Exposure on the Development of Amphibian Larvae.

Description: Triclosan and triclocarban are antimicrobials found in numerous consumer products, while caffeine is the most commonly consumed stimulant by humans. This study was undertaken to determine the effects of triclosan, triclocarban, and caffeine on the development and physiology of amphibian larvae. LC50 values of triclosan and triclocarban were determined after 96 hours for three North American larval species: Acris crepitans blanchardii, Bufo woodhousii woodhousii, Rana sphenocephala, and for a common amphibian developmental model: Xenopus laevis. Amphibian larvae were most sensitive to triclosan and triclocarban exposure during early development based upon 96-hour LC50 values. Heart rates for X. laevis and North American larvae exposed to triclosan were variable throughout development. However, significantly lower heart rates were observed in all larvae exposed to triclocarban. Metabolic rates of X. laevis and R. sphenocephala larvae exposed to triclosan were significantly affected in larvae exposed to ½ LC50 and the LC50 concentration. Metabolic rates of X. laevis larvae exposed to triclocarban were significantly affected by exposure to ½ LC50 concentrations in three of four stages investigated. No significant differences were observed in North American larvae exposed to triclocarban. Tissue uptake, lipid uptake, tissue bioconcentration factor (BCF) and lipid BCF of triclosan and triclocarban were investigated in three developmental stages of X. laevis, and in one developmental stage of B. woodhousii woodhousii, and R. sphenocephala. For most tissue and lipid uptake values, a significant increase was observed as exposure concentration increased. Tissue and lipid BCF values were dependent upon both stage and species. Chronic and acute effects of caffeine were determined in X. laevis larvae. Acute 96-hour LC50 values in four developmental stages were > 75,000 ug L-1 caffeine and heart rates were significantly different at the two earliest developmental stages. Larvae chronically exposed to caffeine reached metamorphosis at the same time as controls. Changes in ...
Date: August 2009
Creator: Palenske, Nicole Marie

Effects of Turbidity on Gilling Rates and Oxygen Consumption on Green Sunfish, Lepomis cyanellus

Description: Laboratory studies conducted at 5, 15, 25, and 35 C measured changes in gilling rates and oxygen consumption of green sunfish in response to exposure to bentonite clay suspensions. The tests indicate that gilling rates are not affected by bentonite clay suspensions below 2125 FTU at 5 C, 1012 FTU at 15 C, and 898 FTU at 25 C. At turbidity levels exceeding 1012 FTU at 15 C and 898 at 25 C, gilling rates increased 50-70%. Tests were inconclusive at 35 C. Oxygen consumption rates were found to be unaffected by turbid suspensions below 3500 FTU at all four temperatures. Evidence suggests that increased gilling rates under highly turbid conditions are a means of compensating for reduced respiratory efficiency and a strategy for maintaining a constant oxygen uptake. Evidence indicates that the cost of increased gilling rates is probably met by a reduction in activity.
Date: May 1974
Creator: Horkel, John Duane

The Effects of Two Approaches to Reading Instruction upon the Oral Language Development of First Grade Pupils

Description: The problem of this study was to compare the relative gains made in the development of oral language skills in two groups of first grade pupils when two different approaches to beginning reading instruction were used. The two approaches were: (a) the language experience approach, Approach A, and (b) the traditional basal reader approach, Approach B. The six aspects of oral language development considered were: extent of verbalization, spoken vocabulary, expressions of tentativeness, use of structural patterns, colorful and vivid expressions, and use of mazes.
Date: January 1966
Creator: Giles, Douglas Elbert, 1932-

The Effects of Two Extrinsic Incentives on the Classroom Success of Disadvantaged Middle-School Students

Description: This study tests the effectiveness of a program designed to use extrinsic incentives in improving the motivation of disadvantaged students to achieve academic success. This study seeks to determine whether the specific extrinsic rewards provided in the program actually improve the success of students on classroom tests. A secondary purpose of the study is to assess the extent to which that success, if achieved, becomes itself a reinforcement sufficient to maintain continued success in the classroom. Ignoring age and grade, students from the sixth, seventh, and eighth grades were grouped by their skill level in mathematics and assigned to an individual teacher. The study was conducted during four consecutive two-week periods. Base-line data were obtained during the first two-week period of both experimental and control students under regular classroom conditions. Extrinsic incentives were applied to the experimental group during each of the following two-week periods and identical measures were taken during the same period of both the experimental and control groups. The analysis-of-covariance statistical treatment was used to compare changes on test success. The .05 level of confidence was held as the standard for statistical significance. Two extrinsic incentives, a free movie and a monetary reward, were employed to bring about improved performance on mathematical tests. Separate and combined effects of the incentives were examined for the total group and for subgroups based on sex, ethnicity, and initial mathematics ability.
Date: August 1973
Creator: Ward, Gerald Wilson

The Effects of Two Methods of Training on Arm Strength

Description: A study was made to investigate the relative effectiveness of two methods of training on the development of arm strength. The purposes of the study included the following: 1. To determine functional arm strength of male students enrolled in physical education classes selected for the study. 2. To conduct specific exercise programs in each of the selected classes. 3. To determine the relative effectiveness of the selected programs in developing arm strength.
Date: August 1966
Creator: Thompson, Charles J.

The Effects of Two Types of Consequence Delivery on Task Acquisition.

Description: The effects of two consequence delivery methods on task acquisition were evaluated within a multi-element design. A typical 3 year-old child and a 4 year-old child with autism participated in this study. The task for both children was to select a picture after the experimenter said its name. The consequence in one condition consisted of the experimenter handing the edible item to the children. The consequence in the other condition consisted of the children retrieving the edible item directly from the apparatus, located in a crevice underneath each picture. Results show slightly quicker acquisition in the condition where children retrieved the edible consequence. However, it is possible that other variables had greater influence on the task acquisition.
Date: August 2005
Creator: Jenkins, Juliet

The Effects of Two Types of Group Counseling Procedures with Junior College Students

Description: The problem with which this investigation was concerned was to measure personal adjustment, emotional adjustment, home adjustment, and self-concept changes that took place in junior college students as a result of one-counselor group counseling and male-and-female co-counselor group counseling. The rationale for male-and-female co-counselor group counseling relied on the formation of a simulated family in which individuals could socialize their feelings.
Date: August 1971
Creator: West, William George

The Effects of Two Types of Teaching Reading Upon Reading Progress, Social Maturity Progress, and Arithmetic Reasoning and Computation

Description: The problem of this thesis is to evaluate the progress in general reading efficiency of a group of children taught by the socialized group plan, as compared to a group of children taught by the traditional reading plan and to determine whether the socialized group plan aids in the development of certain other general attributes, such as arithmetic reasoning, arithmetic computation, and social maturity growth.
Date: 1942
Creator: Mathis, Floye

Effects of UE Speed on MIMO Channel Capacity in LTE

Description: With the introduction of 4G LTE, multiple new technologies were introduced. MIMO is one of the important technologies introduced with fourth generation. The main MIMO modes used in LTE are open loop and closed loop spatial multiplexing modes. This thesis develops an algorithm to calculate the threshold values of UE speed and SNR that is required to implement a switching algorithm which can switch between different MIMO modes for a UE based on the speed and channel conditions (CSI). Specifically, this thesis provides the values of UE speed and SNR at which we can get better results by switching between open loop and closed loop MIMO modes and then be scheduled in sub-channels accordingly. Thus, the results can be used effectively to get better channel capacity with less ISI. The main objectives of this thesis are: to determine the type of MIMO mode suitable for a UE with certain speed, to determine the effects of SNR on selection of MIMO modes, and to design and implement a scheduling algorithm to enhance channel capacity.
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Date: August 2016
Creator: Shukla, Rahul

The Effects of Unilateral Exercise Upon the Reaction-Movement Time of the Exercised Arm and the Contralateral Arm

Description: The purposes of the study were to determine (1) the effect which exercise of the nondominant arm would have upon the reaction-movement time of the dominant and nondominant arms, (2) the degree to which fatigue transfers from one arm to the other arm, and (3) the influence of lateral dominance upon the reaction-movement time of both the dominant, and nondominant arms.
Date: May 1973
Creator: Schmidt, Dianne L.

The Effects of Using Children's Literature with Adolescents in the English As a Foreign Language Classroom.

Description: This study provides quantitative and qualitative data about the effects of using children's literature with adolescents in a language classroom and the role of children's literature in students' second/foreign language development, including listening, speaking, reading, and writing skills. The study presents qualitative data about the role of children's literature in developing more positive attitudes toward reading in the second/foreign language and toward reading in general. With literature being a model of a culture, presenting linguistic benefits for language learners, teaching communication, and being a motivator in language learning, this study presents empirical data that show that inclusion of children's literature in adolescents' second/foreign language classroom promotes appreciation and enjoyment of literature, enhances the development of language skills, stimulates more advanced learning, and promotes students' personal growth.
Date: December 2006
Creator: Belsky, Stella

The Effects of Using Information Technology to Support Evaluation of Feedback and Implementation of Adjustments in an Organization's Strategic Planning Process

Description: Organizations that must respond quickly to environmental pressures look for tools to assist in that response. Information technology may be one tool to facilitate the response. In this study the possible effects of using information technology, specifically a decision support system, in the feedback segment of one organization's strategic management loop were examined. The organization was one region of the Board of Probation and Parole in a central state. Personnel included administrators, parole officers and clerical workers. The information technology was an off-the-shelf software product called PlanRight. This study is significant for two reasons: a new application for information technology was examined and the adequacy of a generic computerized tool designed to be suitable for various operations was explored. This study was a case study. Two months of data were taken prior to the implementation of the decision support system, and four months of data were taken after the system was implemented. Questionnaire data taken before system implementation provided descriptive characteristics of the organization. Follow-up surveys and interviews at the conclusion of the study were used to evaluate employee perceptions. The study was done in three phases. During phase one questionnaires were distributed and returned. During phase two, goals, plans and evaluation criteria were formulated and plans were implemented. Feedback was obtained and evaluated through the use of the decision support system enabling reaction to the feedback data. In phase three perceptions of administrators and parole officers were elicited using follow-up surveys and semi-structured interviews. Three propositions guided the evaluation of the study's outcomes. These propositions dealt with performance toward goal achievement, satisfaction with feedback processes and quality of plans formulated for the project. Performance was moderately successful. Satisfaction with processes was high. Speed of obtaining feedback was considered high by administrators and paroled officers. Quality of processes and outcomes ...
Date: May 1997
Creator: Kemm, Elizabeth

The Effects of Using Integrated Testing and Skills Software in Reading Instruction for At-risk Students

Description: The purpose of this study was to determine the effects of using computer-managed, integrated testing and skills software with individualized homework packets on the reading achievement and attitudes of at-risk students in a low achieving urban school. An additional purpose was to determine teacher attitudes toward using technology to deliver, measure, and manage instruction.
Date: December 1992
Creator: Pitre, Barbara J. (Barbara Jean)

Effects of Using Logic and Spatial Cybergames to Improve Student Success Rates in Lower-Division Chemistry Courses

Description: A study was conducted to investigate the relationships between cybergaming treatment groups and the control group (N = 99: ncontrol = 8; nlogic = 29; nspatial = 30; ncombination = 32) with success in the organic chemistry I course as measured by achievement over a 10-week period. The treatment groups included logic training, spatial training, and combination logic-spatial training. Students' ability was measured by pre/post exams using the Group Assessment of Logical Thinking (GALT) to measure logic ability, Purdue Visualizations of Rotations (ROT) test to measure spatial skills, and the General-Organic-Biochemistry (GOB) Exam to measure content attainment. Finally, students' responses about participation in this experience were evaluated using open- and closed-ended questions on a self-developed survey. A second study was conducted to evaluate the relationship between the cybergaming treatment and control groups (N = 88: nexperimental = 27; ncontrol = 61) with success in the general chemistry I course as measured by achievement and final course averages and grades. The cybergaming treatment group underwent intensive combination logic-spatial training for 10 weeks. Students' progress was measured using three pre/post instruments: Group Assessment of Logical Thinking (GALT) measured logic ability, Purdue Visualizations of Rotations (ROT) Test measured spatial skills, and the California Chemistry Diagnostic Exam measured content attainment. Finally, students' responses about their participation in this experience were evaluated using open- and closed-ended questions on a self-developed survey. Analyses of the data were performed to determine the relationships between cybergaming treatments and control groups in organic chemistry I and general chemistry I courses. In organic chemistry I results showed no statistical or practical significance as to students' success. In general chemistry I results indicated statistical significance and medium practicality for students with an average grade of C and for females over males as to improvement of spatial skills.
Date: May 2011
Creator: Manrique, Carissa Janice

The Effects of Using Networked Integrated Testing and Skills Software and Parental Involvement on Achievement, Attitude, and Self-esteem of At-risk Students

Description: The purpose of this study was to determine whether using integrated, networked testing and skills software combined with parental participation would increase students' achievement in reading, improve students' self-esteem and improve attitude toward school. Further, the purpose was to determine if parental participation promotes improved attitude toward school.
Date: December 1992
Creator: Robinson, Gary E. (Gary Edwin)

Effects of Varied Intervals of Rest between Warm-Up and Performance on 440-Yard Dash Times

Description: A comparative study was made of the effects of varied time intervals of rest between warm-up and performance in the 440-yard dash by students in selected physical education classes at North Texas State University during the spring semester of 1967. This study was made to determine if the length of a rest interval after cessation of warm-up activity has any significant effect upon the subsequent performance in a 440-yard dash, and to determine if any length of rest interval facilitates performance in a 440-yard dash.
Date: August 1967
Creator: Hutterly, William U.

Effects of Vegetation Structure and Canopy Exposure on Small-scale Variation in Atmospheric Deposition Inputs to a Mixed Conifer Forest in California

Description: Data on rates of atmospheric deposition is limited in many montane ecosystems, where high spatial variability in meteorological, topographic, and vegetation factors contributes to elevated atmospheric inputs and to the creation of deposition hotspots. Addressing the ecological consequences of increasing deposition in these areas will require a better understanding of surface controls influencing atmospheric deposition rates at both large and small-scales. The overarching objective of this thesis research was to understand the influence of vegetation structure and canopy exposure on small-scale patterns of atmospheric sulfate, nitrate, and chloride deposition inputs to a conifer forest in the Santa Cruz Mountains, California. Throughfall ion fluxes (i.e., ions delivered in water that pass from the forest canopy to the forest floor), bulk deposition (i.e., primarily wet deposition), and rainfall data were collected during the rainy period from October 2012 to May 2013. Throughfall SO42-, Cl-, and NO3- fluxes were measured beneath eight clusters of Douglas fir (Pseudotsuga menziesii) trees (three trees per cluster) differing in tree size (i.e., diameter at breast height; DBH) and canopy exposure. In each cluster, a throughfall collector was placed 1-meter from the bole of an individual tree, for a total of 24 individual collectors. The position of each throughfall collector was recorded with a Trimble® GPS. In addition, tree height, tree diameter, and leaf area index, were measured for all trees. LiDAR data were obtained from GeoEarthScope’s Northern California Airborne LiDAR project and used to model the elevation (DEM), canopy surface height (DSM), tree height (CHM), slope, and curvature of the canopy surface across the entire study area. Over the rainy season, total throughfall flux of SO42--S, a conservative tracer of total deposition (wet + dry + fog), to Douglas fir clusters ranged from 1.44 - 3.84 kg S ha-1 wet season-1, while dry and fog deposition ranged ...
Date: May 2014
Creator: Griffith, Kereen

Effects of Venture Team Demographic Characteristics on Team Interpersonal Process Effectiveness in Computer Related Venture Teams

Description: In order to remain competitive, firms must be able to merge diverse, differentiated people into teams. In comparison to solo ventures, venture teams not only offer a broader base of physical and financial resources and varying points of view, but also positively influence the profitability, growth, and survivability potential of new ventures. Despite the growing importance and potential benefits offered by venture teams, relatively little is known about assembling and maintaining effective venture teams in the field of entrepreneurship. More specifically, information is needed to understand what composition and combination of demographic characteristics of team members would contribute to the effectiveness and success of a venture team. In this study the relationship between venture team demographic characteristics and team effectiveness (which is defined in terms of the interpersonal process of venture team members in their group activities) is investigated. The demographic characteristics examined include average age, age heterogeneity, average level of education, educational background heterogeneity, gender heterogeneity, and functional background heterogeneity. A field study, involving face-to-face and telephone interviews with the venture teams is used to gather data from40 computer related venture teams in a large midwest U.S. city. The venture teams are identified through the local Chambers of Commerce, peer referrals, and library research. Information is gathered on demographics and team interpersonal process effectiveness using a pre-validated instrument. Data are analyzed using regression analysis. The results indicate that average age negatively and significantly relates with team interpersonal process effectiveness. Furthermore, average level of education positively and significantly relates with team interpersonal process effectiveness. The other demographic variables, age heterogeneity, educational background heterogeneity, gender heterogeneity, and functional background heterogeneity do not produce significant relationships.
Date: August 1996
Creator: Ochani, Manju