Digital Commons Network^™

The Effects Of Herbicides On Microbial And Mycorrhizal Populations In Native Prairie, Corn, And Non-Native Prairie Vegetation, Using The Biolog Technique, Susann E. Ahrabi-Fard

Dissertations and Theses @ UNI

Soil bioremediation has primarily focused on the use of free living, actively growing microorganisms to degrade toxic organic substances. Recently, however, plants and rhizosphere activity, including mycorrhizal fungi have been increasingly studied to determine the role that consortial assemblages may play in bioremediation. While the enhanced absorbtion of nutrients, water, and minerals by mycorrhizal fungi has been well documented, less is known about their role in the degradation of soil contaminants. Using the Biolog plate technique, microbial communities were characterized in Native Prairie, Corn, and Non-Native Prairie vegetative strips prior to, and after two applications of Acetachlor, Alachlor, and Atrazine. …

Youth-Serving Agency's Prevention And Intervention Programs For Gangs, Julianne Gassman

Dissertations and Theses @ UNI

The purpose of this study was to describe the perception of directors of youth-serving agencies on what prevention and intervention programs have been implemented by youth-serving agencies in eastern Iowa. Directors of youth-serving agencies in the following cities in Iowa answered the questionnaire (Gang Program Assessment Questionnaire): Waterloo, Cedar Falls, Dubuque, Cedar Rapids, Davenport, Iowa City, Coralville, Adel, Ankeny, Bondurant, Indianola, Johnston, Knoxville, Nevada, Newton, Pella, Pleasant Hill, Ames, Des Moines, Makquoketa, and Urbandale.

The Gang Assessment Program Questionnaire was used to analyze the extent to which gangs were perceived as active in each city as well as expectations for …

Passages: A Case Study Of An Iowa Female Secondary Principal, Victoria L. Robinson

Dissertations and Theses @ UNI

The purpose of this exploratory case study was to identify and describe one female Iowa secondary principal's career path to the principalship in an Iowa public high school. Several factors were considered in the selection of the participant including: demographics, administrative experience, and her willingness to spend time in the interview process. To provide semi-structure to the interviews and in turn suggest the conceptual frame for analyzing the data, the following questions were formulated:

1. What were the experiences which served as perceived barriers in the career path to the high school principalship for one Iowa female high school principal? …

Early Childhood Teachers' Beliefs And Practices Related To Promoting Children's Conflict Resolution In Constructivist Classrooms: A Study Of Two Teachers, Yuko Hashimoto

Dissertations and Theses @ UNI

The study involved six weeks of classroom observations and in-depth interviews with two teachers, kindergarten and first grade, who are currently engaging in an on-going process of implementing constructivist education in a public school in Missouri and whose teaching practices are considered to be exemplary. The purpose of the study was twofold: (a) to describe and analyze the teachers’ practical approaches in promoting children’s conflict resolution in the classrooms and (b) to examine how the teachers’ beliefs and practices related to conflict resolution reflect the theoretical framework o f the constructivist program.

The results of the data collection were analyzed …

Direct And Television-Mediated Observation Of Verbal Interaction In The Classroom, Terri Mcdonald

Dissertations and Theses @ UNI

The purpose of this study was two-fold: (a) to investigate differences in preservice teachers' ability to identify and report verbal interaction in the classroom during direct observation as compared to television-mediated observation, and (b) to examine the advantages and disadvantages of direct and television-mediated classroom observation as perceived by preservice teachers.

Subjects in this study were preservice teacher education majors (N = 96) from four university class sections enrolled in professional sequence courses prior to student teaching. The data were analyzed using a 2 x 2 ANOVA (mode of observation x tally type). The independent variable of mode of observation …

Expertise In Clinical Nursing Educators: An Exploratory Study, Nancy Ann Kramer

Dissertations and Theses @ UNI

A primary goal of professional education is to prepare practitioners who can provide quality care essential to the well-being of individuals and society. An essential component of professional education is a practiced-based experience. The purpose of this study was to identify and describe the qualities of clinical nursing educators who were recognized by peers as being expert clinical practitioners. This study was exploratory and non-experimental. A qualitative approach was used. Through observations and interviews, beginning descriptions and explication of dimensions of expertise of clinical nursing educators were achieved.

The population for this study was selected from nursing faculty of 10 …

The Women Superintendents Of Iowa: A 1990'S Analysis, Joen M. Rottler

Dissertations and Theses @ UNI

Historically, Iowa has had few women superintendents of K-12 public schools. Societal changes, political changes, and legislation, such as affirmative action, have had no impact on gender balance in the superintendency in Iowa. The number of women superintendents in Iowa remains low. Of 397 superintendents in Iowa, during 1993-94, only 14 were women. This qualitative study examines the characteristics of current women superintendents of Iowa. Specifically, the following aspects of career development were examined: childhood and adolescent characteristics, personal and professional characteristics, and career path. The experience of being a woman superintendent and gender related aspects of leadership were also …

A Sociometric Analysis Of The Informal Networking Patterns Of Iowa's Public School Superintendents, Thomas M. Hoover

Dissertations and Theses @ UNI

The purpose of this study was to describe the informal communication network of public school superintendents in the state of Iowa. This investigation was initiated because the literature on the superintendency remains silent to the topic of communication relationships among superintendents. For purposes of this study, networking was defined as activities leading to the formation of peer relationships resulting in the acquisition of useful information, advice, moral support, or socializing and mentoring opportunities.

The collection of data was made possible by means of a self-reporting survey mailed to all public school superintendents in Iowa. The survey reflected the standard approach …

Computer Mediated Communication: Elements Impacting Sustained Usage By Iowa Elementary And Middle School Teachers, Philip M. Hibbard

Dissertations and Theses @ UNI

The purpose of the study was to examine, using a case study methodology, interactions among a group of Iowa teachers involved in a computer mediated communication project, to better understand those elements which may impact sustained usage of computer mediated communication. The study involved examination of one year's worth of on-line journal postings and interactive conferences, and interviews with the 22 teachers involved in the project.

The multiple sources of data collected were analyzed using a methodology known as constant comparative, and the analysis presented according to the following themes:

1. What topics did the participants discuss while using computer mediated …

An Investigation Of Diameter Measurement Repeatability Using A Coordinate Measuring Machine And A Multi-Baseline Repeatability Assessment Methodology, Bruce Marsh

Dissertations and Theses @ UNI

The need for reliable and consistent measurement has become more acute with the use of statistical process control (SPC), gage repeatability and reproducibility (Gage R&R) assessment, and high precision, computer-controlled gaging systems. Although it is often overlooked, the inspection methodology under which various features are inspected has an impact on Gage R&R results. This notion was confirmed when a 1993 thesis study substantiated inspection methodology as a source of measurement variability in direct computer-controlled, coordinate measuring machines (DCC/CMMs). Although this study explored a methodology to bring measurement variability under statistical control, the tested assessment methodology--single baseline repeatability assessment--was not validated. …

An Investigation On The Processing And Characterization Of (Thallium(0.5-X) Lead(0.5-X) Europium(2x)) Strontium(2-Y) Barium(Y) Calcium(2) Copper(3) Oxygen(Z) High-Temperature Superconductor To Determine The Optimum Barium Concentration And Study The Effects Of Doping Europium In Thallium And Lead Sites, Zifan Ju

Dissertations and Theses @ UNI

This research focused on (Tl_0.5-xPb_0.5-xEu_2x)Sr_2-y Ba_yCa₂Cu₃O_z compound to determine the optimum y (Barium concentration), and then studied the effects of doping Eu in Tl, Pb sites. Studies on optimum y give rise to a high quality superconducting material as a target material for sputter deposition of thin films for electronics applications. Studies on doping Europium (Eu) is a new investigation and might lead to better understanding of the structural properties of the superconductor.

The experiment was conducted in three steps as follows:

1. Optimizing the sample fabrication …

An Investigation Of The Energy And Transportation Component For Junior High School Technology Education Programs In Taiwan, Chang-Cheng Chen

Dissertations and Theses @ UNI

The purpose of this study was to identify the appropriate content of the Energy and Transportation (E&T) unit for use in instruction in the junior high school Technology Education (TE) programs in Taiwan. Another purpose was to provide the Taiwanese higher education program administrators and educational planners with practical information for use in effectively designing and implementing preservice and in-service teacher preparation programs.

Survey instruments were developed through a literature review and validated by nine experts in E&T. The samples included 400 stratified and randomly selected TE teachers from four geographic parts of Taiwan, 200 stratified and randomly selected industrial …

A Comparison Of Measurement Reliability Between A Sonic Digitizer And A Tape Measure On A Complex Three-Dimensional Object, Diane Darlene (Wheeler) Schou

Dissertations and Theses @ UNI

Digitizers and scanners have begun to replace traditional devices for measuring three dimensional objects. However, there is a shortage of relevant research to compare digitizer tools with other measuring devices. The objective of this study was to compare the measurement reliability of a sonic digitizer to a traditional measuring tool, the tape measure, for measuring a complex, three-dimensional object. It was hypothesized that:

1. H₁ Data from measurements with the digitizer vary less than data from measurements with a tape measure at the 0.05 level of significance.
2. H₂ The data from eight complex surface measurements taken with a digitizer …

Maintenance Conditions And Occupant Behavior In Government Provided Housing In Lagos, Nigeria, Paul Abayomi Bajere

Dissertations and Theses @ UNI

Maintenance conditions and occupant behavior towards maintenance in government housing in developing countries are universal problems. Perceptions, construction technology, competencies, tenureship, cultural tradition, and demographic factors have been identified as major constraints influencing housing maintenance behavior. There was a need for this study because limited literature exists on maintenance of urban government provided housing in Nigeria. Also, the degree of success of the government's efforts concerning environmental cleaning has not been remarkable.

The primary purpose of this study was to investigate the maintenance of government provided housing, as perceived by the residents and observed by the researcher, to determine the …

Effect Of Light Source On The Sorting Performance Of A Vision-Based Robot System, Johnny T. Li

Dissertations and Theses @ UNI

Industries look toward computer vision as a means to automate materials handling. To make this choice more appealing, useful and feasible vision applications must be explored. However, illuminance variation in the factory environment can undermine the capability and applicability of vision-based control systems. The purposes of this study were (a) to design and develop a vision-based robot material sorting system, (b) to determine the optimal settings for this system under fluorescent and incandescent lighting for two different color parts on a moving conveyor, and (c) to determine the sorting performance of this system under each light source.

The main components …

The Effects Of Telephone Technology On Saudi Arabian Society, Khalid I. Otibi

Dissertations and Theses @ UNI

The current research explores the significance of the introduction of telephone technology into Saudi Arabia. The problem addressed by the research was to identify and describe the cultural and economic significance that the telephone has had in Saudi Arabia. The purpose of the research was specifically to study the significance that telephone technology has in the three areas of family ties, business, and transportation. The methodology began with the development a data-collection document. An English version of the document was administered as a pilot test to students at the University of Northern Iowa. This pilot test revealed that the document …

An Investigation On Using Solid Waste Materials As Aggregate Substitute In Cementitious Concrete Composites, Ibrahim Hussein Shehata

Dissertations and Theses @ UNI

The problem of disposing and managing solid waste materials in the United Slates and other industrial countries has become one of the major environmental, economical, and social issues. A complete waste management system including source reduction, reuse, recycling, landfilling, and incineration needs to be implemented to control the increasing waste disposal problems. Of the above options, recycling is the most promising waste management process to the disposal of materials in the waste stream. One of the most promising markets to utilize recycled waste materials successfully on an open-loop basis is the construction industry.

The purpose of this research study was …

An Examination Of The Environmental Issues Instruction Program: Student Attitude, Knowledge, And Subsequent Student Behaviors, Randi Montag Peterson

Dissertations and Theses @ UNI

The purpose of this study was to determine the effectiveness of the Environmental Issues Instruction program as an environmental education delivery method, linking environmental education with student attitudes towards environmental issues, student knowledge of individual environmental issues, and subsequent student behaviors. The study utilized a one group pre-post test design. No control group was used. Statistical analysis revealed statistically significant gains in student's pre-to-post test scores for the variables. "Student Attitudes About Environmental Issues," "Knowledge of Specific Environmental Issues," and "Solving Environmental Issues." Environmental education is a process that leads to responsible individual and group actions. Research has shown (Childress, …

Elementary Teachers’ Perceptions Of Computer Applications In The Classroom, Angela S. Briley

Dissertations and Theses @ UNI

The purpose of this descriptive study was to identify elementary teachers' (K-5) perceptions of computer usage in the classroom. The three areas that were addressed are: classroom computer access, computer professional development and training, and teachers' expectations towards computers usage in the classroom. A survey was distributed to teachers at nine elementary schools during planned faculty meetings. Of the 295 teachers surveyed, 285 surveys were completed, resulting in a 96.6% response rate. Overall, teachers had positive perceptions of computer use in the classroom. Approximately 80.6% of teachers reported using computers in their classrooms. However, when asked about the number of …

Influence Of Physical Fitness On Susceptibility To Noise-Induced Temporary Threshold Shift In Females, Stacy Claire Bukatz

Dissertations and Theses @ UNI

This study investigated the influence of physical fitness on susceptibility to noise-induced temporary hearing loss in 33 females of various fitness levels, and the relationship between temporary threshold shift (TTS) and distortion product otoacoustic emission (DPOAE) measurements. Behavioral audiometric thresholds and DPOAE measurements were obtained at 2000, 3000, 4000, and 6000 Hz prior to and immediately after 10 minutes of exposure to 108-dB SPL narrow-band noise centered at 2000 Hz. The greatest TTS and largest reduction in DPOAE amplitude occurred at·3000 Hz. However, no significant correlation was observed between TTS and DPOAE at any frequency or between any of the …

Ultrasound Modified Ferric Hydroxide/Cupric Ion Adsorption And Sequestration At Varying Ph Levels, Humberto Campos

Dissertations and Theses @ UNI

This study was undertaken to determine if hydrous metal oxide adsorption, an important treatment method used to remove adsorbates from aqueous solution, could be enhanced through ultrasonic irradiation. A model system based on preformed hydrous ferric oxide as the adsorbent and copper as the adsorbate was investigated. Brief exposure of the preformed hydrous ferric oxide floe to intense ultrasonic radiation (ca. 13 Watts/cm2 ) in the presence of copper species effectively disrupted the flocculated particles permitting the copper adsorbate to access adsorption sites previously isolated within the floe. The experimental data indicate that ultrasonic disruption of pre-formed hydrous ferric oxide …

Methods And Materials Of Music Composition, Philip H. Carver

Dissertations and Theses @ UNI

Music composition in the twentieth century is an eclectic discipline. For the past one hundred years composers have employed a vast array of techniques to express their music, more so than in any other era in history. No universally accepted "common practice" exists for the contemporary writer. Although certain aesthetic considerations regarding style, form, and content are pondered by the composer, their applications vary widely. The composer is compelled to create not only a cohesive piece of music, but also define the very compositional parameters that are to be used-and these parameters quite often are different for every composition. This …

Characteristics Of Batterers Convicted Of Domestic Abuse In The Batterers’ Education Reform, Jacquelyn E. Powell

Dissertations and Theses @ UNI

The information obtained from this study will give an indication as to whether the abusers in this area share common characteristics of the abuser. By identifying these characteristics, it may be possible to target individuals prone to practice abusive behavior, and possibly interrupt the cycle by intervening with education and prevention strategies to combat the problem.

The purpose of this study was to ascertain selected characteristics of males convicted of domestic abuse in the Black Hawk County's Batterers' Education Program. The study was to identify selected characteristics of participants court-ordered to attend the Batterers' Education Program. The study investigated demographical …

Female Aggression In Semi-Contact Sports, Karla Ann Sipple

Dissertations and Theses @ UNI

The main purpose of the present study was to investigate female aggression in semi-contact sport. More specifically, two areas were examined: the types of aggression, hostile or instrumental, that occurred in girls basketball and soccer and the types of aggression that were committed within both sports. The subjects (N = 57) for this study were female athletes ( ages 15-18) who were sampled from various Midwestern high schools: basketball athletes (n = 32) and soccer athletes (n = 25). Subjects responded to a modified form of the Bredemeier Athletic Aggression Inventory (BAAGI-S). One way ANOVA's indicated non-significant differences for the …

Exercise And Immune Function In Athletes Over Age 50, Lynda L. Graham

Dissertations and Theses @ UNI

The purpose of this study was to search for relationships between lifestyle factors and the number of upper respiratory tract infections (URTI) suffered per year in older runners. A cover letter and questionnaire were mailed to 1400 members of the Combelt Running Club. It questioned subjects about life-style factors like: (a) education, (b) occupation, (c) race, (d) activity, (e) cold episodes, (f) vitamin/mineral supplements, (g) stress, (h) diet, (i) smoking, (j) alcohol, (k) weight, (1) height, (m) caffeine, and (n) self-remedy for a cold. One hundred and thirty subjects aged 50 years of age and older participated in this study. …

Occupational Stress And Absenteeism Among Promise Jobs Specialists, Kristine Owens

Dissertations and Theses @ UNI

This study was designed to investigate the relationship between selected occupational stressors and absenteeism among PROMISE JOBS specialists across the State of Iowa. The Occupational Stress Inventory (OSI) (Osipow & Spokane, 1987) supplemented with demographic and absentee measures was administered to the entire population of205 specialists in 16 service delivery areas. The service delivery area directors distributed the surveys in their local agencies. The specialists were asked to return the survey questionnaire in the self-addressed pre-paid envelopes. The overall return rate was 104 questionnaires (50. 7%) of the original population. The findings of this study were based upon 90 usable …

Prevalence Of Cardiac Arrhythmias And Ischemic Electrocardiographic Changes In Phase Ii Cardiovascular Rehabilitation Patients At The University Of Iowa Hospitals And Clinics, Kathryn Arlene Martens

Dissertations and Theses @ UNI

The purpose of the present study was to determine the prevalence of cardiac arrhythmias and ischemic electrocardiographic changes during monitored Phase II Cardiovascular Rehabilitation sessions in patients at the University of Iowa Hospitals and Clinics (UIHC). A secondary purpose of this study was to determine if the identified arrhythmias and ischemic electrocardiographic changes documented during monitored exercise sessions had occurred in the patients prior medical history. A third purpose of this study was to determine the monetary cost of telemetry monitoring in during cardiovascular rehabilitation exercise sessions. Subjects consisted of 176 males and 58 females with an average age of …

Metaphors Of Memory, Mary Alice Applegate

Dissertations and Theses @ UNI

Metaphors of Memory is an installation of objects created during my studies in the Master of Arts program at the University of Northern Iowa from August 1995 to December 1996. The work was exhibited at Kamerick Art Gallery at the University of Northern Iowa on December 13-20, 1996. The installation summarizes and objectifies my observations and reflections on sociocultural phenomena arising from memory loss due to Alzheimer's Disease. My recent familial contact with Alzheimer's Disease led me to choose this as a subject for exploration in my art. My work comes from an instrumentalist or pragmatic perspective. Like artist and …

The Effects Of Post Inoculant Additions On Ductile Iron Fade, Travis James Frush

Dissertations and Theses @ UNI

This study involved the investigation of three specific, commercially available, post inoculants for ductile iron and their effect on the magnesium fading rate and chill reducing tendency in a low volume production environment. Although fading effects of ductile iron have been extensively investigated, in general, they apply to high volume production operations. Unfortunately, for the smaller foundry operations, many of the process solutions proposed for the prevention of the fading effects are not applicable or practical. In addition to the small production operations, new process technologies are also excluded from many of these process solutions. For this reason, a study …

Effects Of Refrigeration And Cryogenic Treatments On Austempered Ductile Iron, Gerard R. Thiel

Dissertations and Theses @ UNI

Low temperature treatment, as a method of improving mechanical properties of metals, has been studied and used for well over 60 years. Until recently these treatments have been limited to hardness and wear improvements of high alloy irons and steels. The purpose of this research is to determine the effects of refrigeration and cryogenic treatments on the mechanical properties, including hardness and tensile strength of austempered ductile iron.

This research included the production of a high strength ductile iron of low alloy content capable of being used in either the as cast, conventionally heat treated or austempered condition. Refrigeration and …