Theses and Dissertations at Montana State University (MSU)

Permanent URI for this collectionhttps://scholarworks.montana.edu/handle/1/733

Browse

Now showing 1 - 20 of 11125

1, 8-naphthyridine copper complexes
(Montana State University - Bozeman, College of Letters & Science, 1968) Enwall, Eric Lee
15 kV class underground cable fault tester
(Montana State University - Bozeman, College of Engineering, 1999) Nystrom, Clair Karl
18-beta-glycyrrhetinic acid and methicillin resistant Staphylococcus aureus : from lytic activity to reduced pathogenesis
(Montana State University - Bozeman, College of Agriculture, 2012) Long, Danyelle Renee; Chairperson, Graduate Committee: Jovanka Voyich-Kane; Julia Meade, Jay Hendricks, Michele E. Hardy and Jovanka M. Voyich were co-authors of the article, '18-beta-glycyrrhetinic acid inhibits MRSA survival and attenuates virulence gene expression' in the journal 'Antimicrobial agents and chemotherapy' which is contained within this thesis.
Methicillin-resistant Staphylococcus aureus (MRSA) is Gram-positive pathogen known to cause severe disease in humans. MRSA's resistance to the beta-lactam class of antibiotics makes it an increasing healthcare concern. Over the last two decades there has been a rise in the incidence of community-associated MRSA, specifically pulsed-field gel electrophoresis type USA300 (known to cause severe skin and soft tissue infections). The development of drug therapies against MRSA infections that do not induce resistance and have efficacy against MRSA is a pressing matter. In this study, we investigate the potential of two components in licorice extracts, Glycyrrhizic acid (GA) and 18-beta-Glycyrrhetinic acid (GRA), as effective antimicrobials against MRSA. Using in vitro survival assays, we determined that GRA is directly bactericidal to MRSA. Using a murine model of skin and soft tissue infection, we discovered that topical treatment with GRA reduced severity of MRSA skin and soft tissue infections more rapidly than treatment with GA or a control. The increase in infection clearance was not due to a reduction in bacterial burden, but results indicate that GRA may decrease severity of the infection via an effect on the immune system. Treatment of an MRSA skin infection with GRA reduced expression of KC and G-CSF. To further investigate how GRA treatment led to a more rapid clearance of infection, we analyzed the expression of five S. aureus virulence genes (saeR, hla, RNAIII transcript, mecA, and sbi) after treatment with GRA or GA. GRA rapidly down-regulated four of the five virulence genes in vitro and all five virulence genes in vivo in the skin infection model. The data presented here shows that GRA is bactericidal, assists in decreasing the severity of MRSA infection via down-regulation of virulence genes, and can induce an altered immune response in the host.
The 1952 Montana elections : politics as usual
(Montana State University - Bozeman, College of Letters & Science, 1976) Everett, David Dean
The 1972 Montana State Constitution--its provision for Montana Indians : a promise unfulfilled
(Montana State University - Bozeman, 1981) Eschler, Leonard Edward
A 1975 catalog of alternate and free secondary schools in Montana
(Montana State University - Bozeman, 1975) Lithander, Sherry Lee Miller
The 1985 NCAA financial audit legislation : is it working, from college and university presidents' perspective ?
(Montana State University - Bozeman, College of Education, Health & Human Development, 1992) Gibson, Thomas Harrison
A 20,000-yr-old record of vegetation and climate from Lower Red Rock Lake, Centennial Valley, Southwestern Montana
(Montana State University - Bozeman, College of Letters & Science, 2010) Mumma, Stephanie Ann; Chairperson, Graduate Committee: Cathy Whitlock
A ca. 20,000-yr-old sediment core from Lower Red Rock Lake (LRRL) in the Centennial Valley of southwest Montana was obtained to reconstruct the vegetation, climate, and environmental changes during and following the late-Pinedale Glaciation in the northern Rocky Mountains. The base of core LRRL 06P49 consisted of inorganic silt and clay, deposited when a large glacial lake occupied the eastern Centennial Valley. The glacial lake receded during the late-glacial period when its western outlet stabilized. Prior to 17,000 cal yr BP, high pollen percentages of Juniperus, Poaceae, Asteraceae, and other herbs as well as low pollen accumulation rates suggest cold dry conditions. The sparsely vegetated landscape at LRRL is consistent with paleoclimate model simulations that show southward displacement of the jet stream and a strong glacial anticyclone during the full-glacial period. Between 17,000 and 10,500 cal yr BP, increases in Picea and Abies pollen percentages suggest a shift to subalpine parkland and warmer conditions than before as result of the northward shift of the jet stream and increasing summer insolation. From 10,500 to 7100 cal yr BP, pollen percentages of Picea and Abies decreased and those of xerophytic taxa (e.g., Chenopodiaceae and Pseudotsuga) increased, suggesting development of steppe and open forest. Warmer drier conditions in the early Holocene were likely a response to increased summer insolation and a strengthened Pacific subtropical high-pressure system. From 7100 to 2400 cal yr BP, cooler and moister conditions at LRRL, driven by decreasing summer insolation, led to the expansion of high-elevation conifers, steppe, and wetlands. Increases in Picea and Abies pollen percentages after 2400 cal yr BP indicate further closing of forests at high elevations and even cooler and wetter conditions than before. Examination of the first arrival of Pseudotsuga in pollen records throughout the region shows that its arrival was later at sites on the Atlantic side of the Continental Divide as compared to sites on the Pacific side. The geographic pattern suggests that the Continental Divide posed a topographic or climate barrier in the late-glacial period, delaying the migration of Pseudotsuga menziesii from glacial refugia.
The 2011 Dear Colleague letter: a quantitative analysis of Title IX's impact on sexual violence management
(Montana State University - Bozeman, College of Education, Health & Human Development, 2019) Aderholdt, William David; Chairperson, Graduate Committee: Sweeney Windchief
This is a nationwide policy analysis of the 2011 Dear Colleague Letter - a policy which changed how institutions of education responded to reports of sexual violence. Due to the substantial requirements placed on institutions of higher education as a result of this guidance, there is a need to determine how the policy has impacted the management of sexual violence. To accomplish this, Clery Act data from 2001-2017 were collected from 3,634 institutions of higher education from throughout the United States. Uniform Crime Data, a national crime database, was used as a comparison to determine if any changes to reporting rates were also present in the general population of the United States. The Integrated Postsecondary Data System, a database comparing institutions of higher education, was used to determine if institution characteristics (degree program, sector, residential classification, and size) changed how the 2011 Dear Colleague Letter impacted the management of sexual violence. The datasets were analyzed using single- and multiple-group interrupted time-series analysis. The results of this examination found the 2011 Dear Colleague Letter increased reports of sexual violence through the Clery Act by 350%. Three primary conclusions of this study include: 1) The 2011 Dear Colleague Letter caused a significant increase in the management of sexual violence by institutions of higher education; 2) This increase was not due to an increase in reporting by the general population; and 3) Institutions of higher education implemented the 2011 Dear Colleague Letter guidance despite unique characteristics; however, there existed significant differences between these groups.
20th Century forest-grassland ecotone shift and effects of livestock herbivory
(Montana State University - Bozeman, College of Agriculture, 2005) Sankey, Temuulen Tsagaan; Chairperson, Graduate Committee: Cliff Montagne.
I studied 20th Century lower forest-grassland ecotone shift in the Centennial Valley in southwestern Montana, USA and the Darhad Valley in northern Mongolia and investigated the effects of livestock herbivory on ecotone dynamics. A total of 525 aspen (Populus tremuloides) and 1,703 Douglas-fir (Pseudotsuga menziesii) trees were cored and 10,168 seedlings were counted at five sites along the ecotone in the Centennial Valley. A total of 2,968 Siberian larch (Larix sibirica) were cored and 4,709 seedlings were counted at five ecotones in the Darhad Valley. Tree-age distribution was constructed to determine 20th Century tree establishment. Tree age and location within the ecotone were correlated to describe the process of ecotone shift into the adjacent grassland. To examine livestock herbivory effects on ecotone shift, the number of new trees was correlated with ten different levels of cattle grazing intensity during the last 60 years in the Centennial Valley and with five different grazing regimes during the last 80 years in the Darhad Valley. Three different types of ecotone shift into the adjacent grassland were documented: forest boundary shift, densification, and fairy ring establishment. No evidence of ecotone shift upslope towards the forest was found. Grazing intensity had a complex relationship with tree encroachment. Aspen and Douglas-fir tree encroachment was low at medium levels of grazing intensity, but aspen establishment was higher at low and high grazing levels and Douglas-fir establishment was higher at low grazing levels. Siberian larch tree encroachment was higher at low and high grazing intensities by sheep and cattle, but it was lower at low and medium grazing levels by goat-sheep and goatsheep- cattle mixes. My results implied that grazing can both facilitate and inhibit tree encroachment. I propose a model of grazing effects on tree encroachment that integrates both inhibition and facilitation effects of grazing disturbance. I also propose a conceptual model of lower forest-grassland ecotone shift and a conceptual model of ecotone shift and livestock herbivory effects. My models suggest that grazing can be used as a tool to maintain the equilibrium between forest and grassland vegetation and to increase or decrease forest expansion.
21st century skills in collaborative web-based instruction : the effects on High school students' dynamic inquiry and understanding of genetics concepts
(Montana State University - Bozeman, Graduate School, 2012) Haack, Lori Jo; Chairperson, Graduate Committee: Peggy Taylor.
In order to advance in the 21st Century, students must be able to develop complex inquiry skills and apply critical thinking while mastering understanding of concepts. The purpose of this study was to determine the effects of Web-based collaboration on students' essential inquiry skills and understanding of genetic concepts. The effects on critical thinking, student involvement, and teacher attitudes were also determined. This project considered the effects of using a Wikispaces platform in an introductory biology class at a small rural high school in Northwest, Colorado. Students content understanding and inquiry skills was assessed using pre and postunit assessments, student interviews, and collaborative projects. Students' critical thinking skills was measured through their ability to express with triggering, exploration, integration, and resolution on class posters and discussion post utilizing the Community of Inquiry Framework. Student involvement was determined through the use of teacher observations, student interviews, post on class posters, and Wiki projects. Results indicated that although students initially struggled using a Web-based platform, increases were achieved in concept understanding and critical thinking, while involvement had mixed results. The overall development of collaborative Web-based inquiry improved my teaching attitude and strengthened my ability to lead and conduct inquiry investigations.
3 walls
(Montana State University - Bozeman, College of Arts & Architecture, 2002) Howe, Miranda
Designs and patterns are elemental components in my work. They are not only visual end results, but are very important aspects in my own creative process. In making thousands upon thousands of tiles, stacking, arranging, and grouping them in different stages all around me, I become immersed in the process. The repetition of doing one things over and over again until it becomes a navigational memory for the muscles, allows freedom for the mind to traverse different terrain. Like portions of frescoes crumbing, or paint peeling to reveal what is underneath, I only give fragments of information before one surface stops and another begins. Compelled to cut my tiles into smaller and smaller units, I weave together a tighter, more complex networks of layered information. Organic and invented pattern coincide. Burnt earth, quilting fabric, dried riverbeds, brick streets, ancient ruins, fissures and intrusions are all used to celebrate pattern.
A 3D anatomy app as a learning tool
(Montana State University - Bozeman, College of Letters & Science, 2022) MacKenzie, Michael John; Chairperson, Graduate Committee: C. John Graves
Complete Anatomy is a digital 3D anatomy platform that allows users to manipulate virtual human models. The purpose of this study was to determine whether the students perceived the app as useful, and how they made use of the app to help them understand anatomy and anatomical relationships. At the beginning of the semester surveys and questionnaires were conducted to determine students' initial perceptions of the app. Over the course of the semester, students were given a brief lesson on how to use the app, provided with resources within the app, and given quiz questions based on images created in the app. At the end of the semester surveys, questionnaires and interviews were again conducted to determine of students' perceptions of the app had changed, and to learn how students made use of the app. From the data gathered, students' perception of the app was positive to begin, and became slightly more positive over the course of the semester. Having a brief lesson on how to use the app, and exploring the tools available in the app made a significant difference in the students' comfort with the app. The flexibility of the app to be used when and where they wanted, and the ability to adapt the app to their current study practices were some of the app's greatest strengths according to the students. Complete Anatomy is a powerful, flexible 3D app that students perceive as useful, and in some cases even necessary. Having the ability to work at times and in ways they prefer makes it an app that benefits student learning.
A 3D computer model investigation of biofilm detachment and protection mechanisms
(Montana State University - Bozeman, College of Engineering, 2008) Chambless, Jason Daniel; Chairperson, Graduate Committee: Philip S. Stewart.
A biofilm is a dense aggregation of microorganisms attached to each other and a supporting surface. Biofilms are ubiquitous in industrial environments and are also frequently recognized as the source of persistent infections. Biofilm invasions and biofilm-induced infections are often difficult or impossible to remedy. This dissertation presents the results of a 3D hybrid computer model, BacLAB, which was used to simulate detachment and protection mechanisms of biofilms in a cellular automata framework. Protection against antimicrobials afforded by each of four hypothesized protective mechanisms was investigated in order to examine population survival versus antimicrobial exposure time, and the spatial patterns of chemical species and cell types. When compared to each other, the behaviors of the slow penetration, adaptive stress response, substrate limitation, and persister mechanisms produced distinct shapes of killing curves, non-uniform spatial patterns of survival and cell type distribution, and anticipated susceptibility patterns of dispersed biofilm cells.
4-H students in college activities
(Montana State University - Bozeman, College of Agriculture, 1938) Peterson, Weber H.
5E instruction in a biology classroom
(Montana State University - Bozeman, College of Letters & Science, 2020) Ingwaldson, Holly Marie; Chairperson, Graduate Committee: Greg Francis
The purpose of the study was to determine if students learn scientific concepts better from 5E instruction versus traditional science instruction. Two groups of students were taught genetics concepts in accordance with state standards. The non-treatment group received traditional science instruction while the treatment group received a small amount of traditional instruction followed by 5E instruction. Scores from the end of unit test were compared to see if there was a difference between mean and median values. Statistical testing indicated that students learned scientific concepts better when learning through 5E instruction. Students in the treatment group performed better on the test than students in the non-treatment group.
The 5E instructional method in high school
(Montana State University - Bozeman, College of Letters & Science, 2020) Wieloch, Natalie Frances; Chairperson, Graduate Committee: Greg Francis
This research addressed the question of whether the 5E Instructional Method improves test scores in the science classroom. Students were given a pretest and a posttest for both a nontreatment and treatment unit. The results of those tests were compared. This research did not show a significant difference in tests scores between nontreatment and treatment units. The 5E Instructional Method was a beneficial teaching method because it increased student attitude and engagement, even though it was not found to increase test scores in this situation.
The 5E instructional model for the next generation chemistry classroom
(Montana State University - Bozeman, Graduate School, 2016) Chase, Amy M.; Chairperson, Graduate Committee: Peggy Taylor.
The purpose of this study was to determine if scientific literacy skills centered on the Science and Engineering Practices from the Next Generation Science Standards would be impacted by the 5E Learning Cycle pedagogy. One hundred and three high school general chemistry students participated in this study which took place over the course of four units. Students participated in pre and post treatments that included the Scientific Literacy Skills Exam, the Science and Engineering Practice Survey, and the Elements of Science Learning Survey. In addition, student performance was evaluated on a pre- treatment laboratory rubric scores and four treatment scores. Results suggest an attitudinal and cognitive gain in students' literacy skills gained during the 5E instructional units. The most growth occurred within the Science and Engineering Practice of planning and carrying out investigations, where the highest scores were seen in normalized gain value in rubric comparisons. In addition, this practice received the highest number of student responses to most focused on practice and highest percentage of gain during the Test for Scientific Literacy.
The 5E learning cycle and students understanding of the nature of science
(Montana State University - Bozeman, Graduate School, 2012) Cornelius, Matthew; Chairperson, Graduate Committee: Peggy Taylor.
One of the most important aspects of teaching science is to provide students with the knowledge and tools for them to understand the nature of science (NOS). This project used a teaching technique called the 5E learning cycle. This learning cycle relies heavily on the teacher using inquiry in the classroom to support the students learning of NOS. The results indicated a marked improvement of student growth in NOS.
The 5E learning cycle vs. traditional teaching methods and how they affect student achievement rate, interest, and engagement in a high school physics classroom
(Montana State University - Bozeman, College of Letters & Science, 2020) Ali, Walayat; Chairperson, Graduate Committee: Greg Francis
The main research question I sought to answer was "the 5E learning cycle vs. Traditional teaching methods" and how they affect student achievement rate, interest, and engagement in a high school physics classroom? Students from two eleventh grade classes participated in the study that covered two physics units. Each class learned one unit through 5E learning cycle and one unit through traditional teaching methods. Pre- and post-content tests, surveys, interviews, attitude scales and engagement tally charts were used as data collection instruments. Data were processed using both quantitative and qualitative analysis strategies. The results suggested that Traditional teaching method was more effective to produce higher achievement rate but 5E learning cycle stimulated curiosity ,equipped students with better lab and critical thinking skills ,enhanced interest and improved engagement level .