Theses and Dissertations at Montana State University (MSU)
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Item Assessment of non-lethal tools to assign sex, stage of maturity, and reproductive condition in Burbot Lota lota(Montana State University - Bozeman, College of Letters & Science, 2019) McGarvey, Lauren Marie; Chairperson, Graduate Committee: Christopher S. Guy; Molly A. H. Webb (co-chair); Christopher S. Guy and Molly A. H. Webb were co-authors of the article, 'Description of gametogenesis and assessment of non-lethal tools to assign sex, stage of maturity, and reproductive condition in burbot Lota lota' which is contained within this thesis.; Christopher S. Guy and Molly A. H. Webb were co-authors of the article, 'Assessment of gonad size measured by ultrasound to assign stage of maturity and reproductive condition in burbot Lota lota' which is contained within this thesis.; Christopher S. Guy and Molly A. H. Webb were co-authors of the article, 'The assessment of non-lethal tools to identify mass ovarian follicular atresia in burbot Lota lota' which is contained within this thesis.Non-lethal tools (plasma sex steroid concentrations and ultrasound) were assessed to assign sex, stage of maturity, and reproductive condition (non-reproductive and reproductive) in Burbot Lota lota from Lake Roosevelt, Washington. Gonadal tissue, plasma samples, and gonadal sonograms were collected from Burbot. Gonadal tissue was processed for histological analysis to describe gametogenesis and confirm sex, stage of maturity, and reproductive condition. Plasma testosterone (T) and estradiol-17beta (E2) concentrations were measured by radioimmunoassay. Plasma 11-ketotestosterone (11- KT) concentrations were measured by liquid chromatography-mass spectrometry. Gametogenesis was described by gonadal histology during the entire reproductive cycle. Plasma sex steroid profiles, gonadosomatic index, and ovarian follicle diameter were also described during the entire reproductive cycle. Plasma 11-KT concentrations were used to assign sex with 81% accuracy during the entire reproductive cycle, and plasma 11-KT and E2 concentrations were used to assign sex with 98% accuracy during the reproductive phase (i.e., November to March in Lake Roosevelt). In females, plasma T concentration, plasma E2 concentration, and month were used to assign stage of maturity with 87% accuracy, and plasma T concentration and plasma E2 concentration were used to assign reproductive condition with 98% accuracy. In males, plasma 11-KT concentration, girth at the urogenital pore, and month were used to assign stage of maturity with 73% accuracy, and plasma T concentration was used to assign reproductive condition with 90% accuracy. Ultrasound was used to assign sex with 97% accuracy, and ultrasound measurements of gonad size were a promising tool to assign stage of maturity and reproductive condition. Non-lethal tools (plasma sex steroid concentrations, gonad size measured by ultrasound, and ovarian follicle diameter) were also assessed to identify mass ovarian follicular atresia in female Burbot. Plasma T concentrations and ovarian follicle diameter were promising tools to identify mass ovarian follicular atresia. Nonlethal tools to assign sex, stage of maturity, and reproductive condition will enable fisheries biologists to assess indices of reproductive potential for the Burbot population in Lake Roosevelt. Indices of reproductive potential can be used characterize and monitor population demographics, improve models of population growth, establish sustainable harvest regulations, monitor the effects of management actions, and monitor the effects of environmental stressors.Item Combining acoustic emission and guided ultrasonic waves for global property prediction and structural health monitoring of glass fiber composites(Montana State University - Bozeman, College of Engineering, 2018) Murdy, Paul; Chairperson, Graduate Committee: David A. MillerSince the turn of the century, wind turbines have been rapidly growing in size and are projected to continue growing as the technology develops. These increases in size have led to increased failure rates of the glass fiber composite turbine blades. Because of this, it is of utmost importance to understand failure mechanisms in glass fiber composites and investigate new approaches to predicting failures. This has led to advancements in structural health monitoring of large composites structures by applying sophisticated sensing technologies, in attempts to evaluate material damage states and predict structural failures before they occur. This research has taken a novel approach to apply multiple ultrasonic monitoring techniques, in the form of acoustic emission and guided ultrasonic waves, simultaneously to the mechanical testing of glass fiber reinforced composite laminates. Testing of the composite laminates was conducted in the form of increasing load-unload-reload static tension tests and tension-tension fatigue tests, to measure modulus degradation of the laminates while applying the monitoring techniques. Acoustic emission was used to detect damage events that occurred within laminates in real-time and guided ultrasonic waves were applied periodically to the laminates to observe changes in wave propagation and relate back to damage severity within the laminates. Furthermore, the acoustic emission and guided ultrasonic wave datasets were combined and used to train multivariate regression models to predict modulus degradation of the laminates tested, with no prior knowledge of the laminates' loading histories. Overall, the predictive models were able to make good predictions and showed the potential for combining multiple monitoring techniques into singular systems and statistical predictive models. This research has shown that the combination of the two measurement techniques can be implemented for more accurate and reliable monitoring of large composite structures than the techniques used individually, with minimal additional hardware. Ultimately, this research has paved the way for a new form of smart structural health monitoring, with superior predictive capabilities, which will benefit the renewable energy through reducing maintenance and repair costs and mitigating the risk of wind turbine blade failures.Item Use of ultrasound guidance during cannulation of arteriovenous fistulas or arteriovenous grafts(Montana State University - Bozeman, College of Nursing, 2018) Luehr, Alice Anne; Chairperson, Graduate Committee: Teresa SerightIndividuals who require renal replacement therapy overwhelmingly choose outpatient hemodialysis. In December, 2013, 62.5% of these patients were using an arterial venous fistula (AVF) and 15% were using an arterial venous graft (AVG) for their hemodialysis access (National Institute of Diabetes and Digestive and Kidney Diseases, 2015). Appropriate cannulation techniques are an essential element in access preservation and prevention of access-related complications. Missed cannulations of AVFs result in damage to the fistula (Lee, Barker, & Allon, 2006). Ultrasound-guided cannulation has proven to be an effective technique for the placement of peripheral venous catheters (IVs) and for placement of central venous dialysis catheters (CVCs) (Brannam, Blaivas, Lyon, & Flake, 2004). The purposes of this scholarly project were to determine if ultrasound-guided cannulation of AVFs/AVGs decreased the number of missed cannulations, to determine staff and patient perceptions regarding cannulation, and to implement a quality-improvement project (QIP). The QIP consisted of creating an ultrasound-guided policy and procedure, training program, and competency evaluation at a hospital-based dialysis facility. Analysis of 53 electronic health records (EHRs) determined the number of missed cannulations in relation to the purchase and availability of a bedside ultrasound machine and implementation of the QIP. Likert scale surveys were distributed to staff and patients to determine familiarity with ultrasound-guided cannulation and perceptions concerning access cannulation. Results: Staff surveys demonstrated a need for policy and procedure, training, and competencies for ultrasound guided cannulation. Patient surveys demonstrated a need for more consistent ultrasound use and showed increased patient satisfaction with cannulation experience when ultrasound guidance was utilized. EHR data revealed a 53% reduction in the number of missed cannulations after the purchase and availability of a bedside ultrasound machine for ultrasound-guided cannulation. Conclusion: Implementation of an ultrasound-guided cannulation policy and procedure, training program, and competency helped guide staff with this cannulation technique. Further research is needed to determine if ultrasound guided cannulation should be classified as a best practice technique.Item Ultrasonic emissions in snow(Montana State University - Bozeman, College of Letters & Science, 1973) St. Lawrence, William FrancisItem Resonant ultrasound spectroscopy in complex sample geometry(Montana State University - Bozeman, College of Engineering, 2005) Fig, Matthew Kenneth; Chairperson, Graduate Committee: R. Jay ConantResonant Ultrasound Spectroscopy (RUS) is the study of the mechanical resonances, or normal modes, of elastic bodies to infer material properties such as the elasticity matrix. This powerful technique is based on two physical facts, the first of which is that the resonant response of an elastic object depends on several parameters intrinsic to the object, such as the object's shape, density, elastic constants, and crystallographic orientation. The second is that using these parameters, the resonant spectrum of an object can be calculated. This method has widely been applied to rectangular parallelepipeds (RPPDs) because the use of such simple geometry frees an investigator interested only in acquiring the elastic constants of a particular material from the hindrance of dealing with the additional computational difficulty imposed by more complex sample geometry. In addition to the use of RPPDs, some work has been done with other objects of high symmetry such as cylinders and spheres. The goal of this research was to explore the extension of RUS techniques to objects exhibiting more complex shape. Toward this end, a computational method was developed for handling the addition of complex geometry. This computational scheme was then verified experimentally through the examination of several objects exhibiting complex shapes.