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Integrating Selective Herbicide and Native Plant Restoration to Control Alternanthera philoxeroides (Alligator Weed)

Integrating Selective Herbicide and Native Plant Restoration to Control Alternanthera philoxeroides (Alligator Weed)

Date: December 2011
Creator: Adams, Justin
Description: Exotic invasive aquatic weeds such as alligator weed (Alternanthera philoxeroides) threaten native ecosystems by interfering with native plant communities, disrupting hydrology, and diminishing water quality. Development of new tools to combat invaders is important for the well being of these sensitive areas. Integrated pest management offers managers an approach that combines multiple control methods for better control than any one method used exclusively. In a greenhouse and field study, we tested the effects of selective herbicide application frequency, native competitor plant introduction, and their integration on alligator weed. In the greenhouse study, alligator weed shoot, root, and total biomass were reduced with one herbicide application, and further reduced with two. Alligator weed cumulative stem length and shoot/root ratio was only reduced after two applications. In the greenhouse, introduction of competitors did not affect alligator weed biomass, but did affect shoot/root ratio. The interaction of competitor introduction and herbicide did not significantly influence alligator weed growth in the greenhouse study. In the field, alligator weed cover was reduced after one herbicide application, but not significantly more after a second. Introduction of competitor species had no effect on alligator weed cover, nor did the interaction of competitor species and herbicide application. This ...
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The Development and Application of a Rating Scale for the Evaluation of Business Arithmetic Textbooks

The Development and Application of a Rating Scale for the Evaluation of Business Arithmetic Textbooks

Date: 1941
Creator: Adams, Raymond
Description: The purpose of this study was to prepare a rating scale to be applied as an objective basis in the selection of business arithmetic textbooks. After the rating scale was developed, it was then applied to a number of recently published texts to demonstrate its use and practical value.
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Carlos Muñiz and Social Drama

Carlos Muñiz and Social Drama

Date: May 1973
Creator: Adams, Sarah Sue
Description: The problem with which this investigation is concerned is that of determining the merit of the works of the contemporary Spanish playwright Carlos Muñiz in the area of social drama.
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The Effects of Interactive Reviews and Learning Style on Student Learning Outcomes at a Texas State University

The Effects of Interactive Reviews and Learning Style on Student Learning Outcomes at a Texas State University

Date: May 2008
Creator: Adams, Wesley
Description: This study investigated the effects of interactive lessons and learning style on student learning outcomes in self-defense education classes. The study utilized an experimental design that incorporated four self-defense education classes at the University of North Texas (UNT) during the fall semester 2007 (N = 87). A pre-test was administered during the first week of class to determine prior knowledge of the participants. The Visual Auditory Reading/Kinesthetic Inventory (VARK) was used to assess the learning styles of the students and was completed after the pre-test of knowledge was administered. The treatment group received the interactive lesson and the control received a paper review. The difference between the pre and posttest was used as a measure of improvement of the student's learning outcomes. A 2 (treatment/control) by 2 (pretest/posttest) ANOVA with repeated measures was conducted to examine the differential improvement in knowledge across the intervention. Based on the 2-way ANOVA there was a significant difference between the treatment group and the control group based on their learning outcomes. A repeated measures ANOVA was conducted to determine if there was a significant difference between the groups based on the pre and post test scores. Based on the results of a one week ...
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High-temperature corrosion of aluminum alloys: Oxide-alloy interactions and sulfur interface chemistry

High-temperature corrosion of aluminum alloys: Oxide-alloy interactions and sulfur interface chemistry

Date: December 2000
Creator: Addepalli, Swarnagowri
Description: The spallation of aluminum, chromium, and iron oxide scales is a chronic problem that critically impacts technological applications like aerospace, power plant operation, catalysis, petrochemical industry, and the fabrication of composite materials. The presence of interfacial impurities, mainly sulfur, has been reported to accelerate spallation, thereby promoting the high-temperature corrosion of metals and alloys. The precise mechanism for sulfur-induced destruction of oxides, however, is ambiguous. The objective of the present research is to elucidate the microscopic mechanism for the high-temperature corrosion of aluminum alloys in the presence of sulfur. Auger electron spectroscopy (AES), low energy electron diffraction (LEED), and scanning tunneling microscopy (STM) studies were conducted under ultrahigh vacuum (UHV) conditions on oxidized sulfur-free and sulfur-modified Al/Fe and Ni3Al(111). Evaporative deposition of aluminum onto a sulfur-covered iron surface results in the insertion of aluminum between the sulfur adlayer and the substrate, producing an Fe-Al-S interface. Aluminum oxidation at 300 K is retarded in the presence of sulfur. Oxide destabilization, and the formation of metallic aluminum are observed at temperatures > 600 K when sulfur is located at the Al2O3-Fe interface, while the sulfur-free interface is stable up to 900 K. In contrast, the thermal stability (up to at least 1100 ...
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The Effects of Music and Operant Conditioning on Gross Motor Activity of Profound Mental Retardates

The Effects of Music and Operant Conditioning on Gross Motor Activity of Profound Mental Retardates

Date: January 1968
Creator: Addison, Max R.
Description: It has not yet been demonstrated that music can be used therapeutically with profoundly retarded children. One way these children might be helped to respond to music, and therapeutically benefit from it, would be to use operant conditioning in an effort to enhance gross motor activity and then progressively shape responses until more complex behavior patterns are formed. Once these children can respond motorically in the presence of musical stimuli, continuation of responding may be possible by pairing motor activity with musical stimuli. This experiment investigated the effects of operant conditioning and music on the motor activity of profoundly retarded children in an effort to determine the therapeutic usefulness of music with such children.
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An analysis of the Sonata for Trumpet and Piano by Peter Maxwell Davies, identifying the use of historical forms, and the implications for performance.

An analysis of the Sonata for Trumpet and Piano by Peter Maxwell Davies, identifying the use of historical forms, and the implications for performance.

Access: Use of this item is restricted to the UNT Community.
Date: August 2006
Creator: Adduci, Kathryn James
Description: The Sonata for Trumpet and Piano by Peter Maxwell Davies is one of his earliest works, and a notoriously difficult work to perform. While using serialism and other twentieth-century compositional techniques, this work also uses older historical forms, including sonata-allegro and sonata-rondo forms. An analysis of the work is presented, identifying the older historical forms, and considerations for performers when making decisions on how to perform the work are provided.
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Dynamic Measurement of Intraoral Pressure and Sound Pressure With Laryngoscopic Characterization During Oboe Performance

Dynamic Measurement of Intraoral Pressure and Sound Pressure With Laryngoscopic Characterization During Oboe Performance

Date: December 2011
Creator: Adduci, Michael Douglas
Description: Measurements of intraoral pressure (IOP) and sound pressure level (SPL) were taken of four oboists as they performed two sets of musical exercises: (1) crescendo-decrescendo from pp to ff and back to pp on the pitches D4, G4, C5 and A5, and (2) straight and vibrato performances of the same four pitches at mf. Video images of the vocal tract were also made using flexible fiberoptic nasoendoscopy (FFN). IOP and SPL data were captured in real time by the WinDaq®/Lite software package, with the dB meter located 8-9 inches in directly front of the oboe bell. The study yielded minimum and maximum values from 21.04 to 57.81 mm Hg and from 65.53 to 100.89 dB across all pitches examined. Discussion is included for the following topics: (1) the oboe’s sound envelope, or functional range of IOP and SPL values at different pitch levels, including the nonlinearity in the relationship between IOP and SPL on the oboe, (2) the static activation and kinetic maintenance thresholds for reed vibration, (3) the effect of vibrato on IOP/SPL, (4) the utilization of the vocal tract during execution of dynamic changes and vibrato, and (5) the impact of player experience on control of physical variables.
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Teacher Turnover among Teachers of Students with Emotional and Behavior Disorders

Teacher Turnover among Teachers of Students with Emotional and Behavior Disorders

Date: December 2007
Creator: Adera, Beatrice Atieno
Description: The purpose of this study was to investigate factors that compel teachers of students with emotional and behavioral disorders (E/BD) to quit or stay in their job. Invitations to participate in the study were sent to a sample of educators from each the four census regions of the United States who currently work or have worked in the past worked with students with E/BD and have participated in one or more of the Council for Children with Behavioral Disorders (CCBD) professional development events. A total of 156 educators responded to the online survey and 9 participated in the focus groups. Quantitative information generated from the survey was analyzed using frequency distributions and ANOVA, whereas, qualitative information were analyzed by summarizing and sorting information into different categories. The results were presented in narrative and tabular form and organized in response to each of the research questions. The projected high teacher turnover as depicted in the findings, were mainly attributed to workplace variables and classroom conditions. Both variables are likely to be associated with high levels of dissatisfaction and lack of commitment eventually leading to decisions by teachers of students with E/BD to leave their job. Most respondents perceived themselves as being ...
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An Analysis of Location and Offender Characteristics for Motor Vehicle Theft in Texas from 2001 to 2005

An Analysis of Location and Offender Characteristics for Motor Vehicle Theft in Texas from 2001 to 2005

Date: December 2007
Creator: Adger, Katherine
Description: Motor vehicle theft is the costliest property crime in the United States equaling billions of dollars in losses each year. Despite law enforcement success in decreasing the rate of motor vehicle theft in recent years, the actual number of thefts has increased. It is vital for law enforcement agencies to know who is committing motor vehicle theft and where vehicles are being stolen. This study answers these questions by examining offender demographic characteristics and the location types most targeted for motor vehicle theft in Texas from 2001 to 2005. The state of Texas was chosen because Texas has continually been ranked second in the Federal Bureau of Investigation's Uniform Crime Report for the number of reported incidents of motor vehicle theft in the United States.
Contributing Partner: UNT Libraries