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An Explainable Deep Learning Prediction Model for Severity of Alzheimer\u27s Disease From Brain Images
No full textDeep Convolutional Neural Networks (CNNs) have become the go-to method for medical imaging classification on various imaging modalities for binary and multiclass problems. Deep CNNs extract spatial features from image data hierarchically, with deeper layers learning more relevant features for the classification application. The effectiveness of deep learning models are hampered by limited data sets, skewed class distributions, and the undesirable black box of neural networks, which decreases their understandability and usability in precision medicine applications. This thesis addresses the challenge of building an explainable deep learning model for a clinical application: predicting the severity of Alzheimer\u27s disease (AD). AD is a progressive neurodegenerative disorder that affects the brain and could result in dementia. Early detection of AD is crucial for more precise treatment and enhanced patient outcomes. The diagnosis and prognosis of AD rely heavily on neuroimaging information, particularly Magnetic Resonance Imaging (MRI). The research developed a deep learning model framework that integrates a local data-driven interpretation method (SHapley Additive exPlanation values) to explain the relationship between the predicted AD severity from the neural network and the input MR brain image. This thesis addresses the skewed class distribution using the synthetic minority oversampling technique. To evaluate the performance of the proposed framework, the study performed a comparative analysis using three CNN models: DenseNet121, DenseNet169, and Inception-ResNet-v2. The framework shows high sensitivity and specificity in the test sample of subjects with varying levels of AD severity. To facilitate a better understanding of model performance, five key AD neurocognitive assessment outcome measures and the APOE genotype biomarker were correlated with model misclassifications
Recent Climate Change Influence on Flood Magnitude and Frequency, Channel Widening, and Bar Deposition in Big River, Missouri Ozarks
No full textClimate and land use can control the flood regime of a river and regulate channel form and size over periods of decades to centuries. Recent climate change has increased rainfall intensity and flood magnitude/frequency in many watersheds in the midwestern United States. Thus, river channels affected by more frequent and larger floods are expected to respond by increasing width (or depth) by fluvial erosion to accommodate larger peak discharges. This hypothesis was evaluated along 186 km of the Big River in southeast Missouri by analysis of historical aerial photography, precipitation studies, and United States Geological Survey (USGS) flow gage records. From 1937 to the 1970s, nine of eleven channel segments in Big River decreased in average width by 10% or more with the remaining two segments showing no significant change. In contrast, from 1970 to 2018 all eleven segments increased in width by more than 10% and all but one segment had a wider average width compared to the channel width in 1937. To verify these results, a survey of channel width changes was completed for all USGS gaging sites in the Ozarks Highlands with sufficient records for flood analysis. Like the Big River, most sites indicated more frequent and larger floods since the 1970s. Further, channel widening was indicated at 16 of 24 reaches in other watersheds since 1990 at rates ranging from 0.18 m/yr to 0.26 m/yr. Given that land use has not changed measurably during this period, with even more forest cover present today, climate-driven flooding is probably the main cause of recent channel widening in Big River. Further, while more in-depth study is needed, recent channel widening has been documented at most flow gaging sites along rivers in the Ozarks Highlands. These channel adjustments to larger floods are not only indicative of increased flood risk, but also of physical disturbances to aquatic habitats and water quality problems due to bank erosion and the remobilization of stored sediment
Continuity and Contrast in the Strategic Theories of Four Classic Strategic Thinkers: Sun Tzu, Thucydides, Machiavelli, and Clausewitz
No full textThe purpose of this research paper is to examine the thinking of four classic strategic theorists, namely Sun Tzu, Thucydides, Niccolò Machiavelli, and Carl von Clausewitz, and explore continuity and contrast in their strategic theories. In doing so, this author has structured the paper based on the fundamental architecture of strategy, that is, ends, ways and means. Since the paper specifically addresses military strategy, it first investigates what the ideas of the four theorists are on war as the military means. Then, the paper will explore the theorists’ thoughts on different strategic approaches as ways. Then, the essay will delve into the ideas of the thinkers on politics as the end. The paper argues that the thinking of the classic theorists of strategy is still relevant to the modern strategic challenges
Developing Onsite Detection Methods for Grapevine Vein Clearing Virus and Grapevine Red Blotch Virus
No full textBoth grapevine vein clearing virus and grapevine red blotch virus are detrimental pathogens on grapevines in the Midwestern United States. The most effective method of control for these viruses is early detection and removal of infected vines. A rapid and equipment-free method of detecting grapevine vein clearing virus and grapevine red blotch virus was developed using the isothermal DNA amplification technique, recombinase polymerase amplification, in conjunction with lateral flow strips. The method yields testing results under 35 minutes and can be performed onsite, and thus provides a rapid and grower-friendly diagnostic tool for preventing diseases caused by the two viruses
Insulin is My Fuel
No full textThe assertion that moments of play empower individuals to find balance amidst the tension of creation and destruction is a central tenet of my artistic philosophy. Through the expressive medium of painting, I have discovered that playfulness can serve as a responsive process that facilitates a flexible approach to coping with the complexities of identity, ideology, and morality. This fertile ground for creativity has become a means of defining a sense of life that is informed by my ongoing struggles with a diabetic medical condition. As my body\u27s dependency on insulin necessitates a constant movement between the frustrations of daily management and the hardships of living with a chronic illness, my paintings reflect a playful yet vulnerable exploration of these realities. Through the use of needle-like shapes, variations of 3D installations, and diverse textures and patterns, my work manifests my altered perceptions and serves as a reference to the organic and ever-evolving nature of my journey. Ultimately, my playful approach asks viewers to reflect on their own vulnerabilities and recognize that through moments of uninhibited play, they too can overcome adversity and find balance amidst life\u27s complexities
Magma Residence Times and Pre-Eruptive Processes as Determined by Diffusion Geospeedometry and Textural Analysis—Lascar Volcano, Chile
No full textPetrographic textural analysis and geochemical microanalysis of plagioclase phenocrysts was conducted to model near-liquidus residence times and to gain further insight into processes that occurred within the magma chambers sourcing historical explosive eruptions at Láscar Volcano (NE Chile). Plagioclase crystals were analyzed from representative samples of Stages II (Soncor ignimbrite), III (Tumbres scoria deposit), and IV (Talabre lava, 1993 Plinian eruption). I used laser ablation-inductively coupled plasma mass spectrometry, which was combined with previously collected electron microprobe analyses and electron backscatter images to build a representative dataset of major- and trace element contents, as well as the zoning patterns and petrographic textures present. Analyzed phenocrysts can be grouped into five distinct populations, all of which record a major compositional change, evidenced by a section of reverse zoning and often resorbed zones, between the core and the mantle. A majority of the plagioclase also exhibit low-amplitude oscillatory zoning near the rim of the crystal. These textures have been interpreted as the result of a major magma mixing event that occurs once per stage, followed by smaller-scale fluctuations of conditions within the magma chamber. Major- and trace- element contents of plagioclase phenocrysts from Stages III and IV have also been modeled by diffusion geospeedometry using Python script published by Lubbers et al. (2022) to obtain paired Sr-Mg near-liquidus residence times. These models reveal that plagioclase resides in a warm and eruptible state, at the decadal-to-centennial scale, beneath Láscar prior to eruption. The average timescale has shortened through time, suggesting an increasing rate of small-volume injections of primitive magma, as proposed for Parinacota’s Young Cone; aligning with predictions of relatively short residence times via bulk rock geochemical analysis
Body Condition: Seasonal Effects and Influence on Aggressive Behavior of Ozark Zigzag Salamanders (Plethodon Angusticlavius)
No full textBody condition is a measure of the size of energy reserves such as fat and protein, which can influence health and the ability to obtain resources in aggressive encounters. Individuals with better body condition ultimately experience a fitness advantage. Physiological factors such as sex, reproductive condition, and diet can influence body condition of individuals. Body condition could be affected positively or negatively after an animal is kept in captivity for extended periods of time. In the first chapter, I explore whether sex, season (fall and spring), and time in containment at the laboratory influences body condition. In the second chapter, I examined how body conditions affected aggressive behavior in staged contests between pairs. Contestants were paired in either symmetric (same body condition) or asymmetric (different body condition) pairs. The prediction based on evolutionary game theory is that symmetric contests should result in higher levels of aggressive behavior than asymmetric contests
Development of Interatomic Potential of High Entropy Diborides With Artificial Intelligence Approach to Simulate the Thermo-Mechanical Properties
No full textThe interatomic potentials designed for binary/high entropy diborides and ultra-high temperature composites (UHTC) have been developed through the implementation of deep neural network (DNN) algorithms. These algorithms employed two different approaches and corresponding codes; 1) strictly local & invariant scalar-based descriptors as implemented in the DEEPMD code and 2) equivariant tensor-based descriptors as included in the ALLEGRO code. The samples for training and validation sets of the forces, energy, and virial data were obtained from the ab-initio molecular dynamics (AIMD) simulations and Density Functional Theory (DFT) calculations, including the simulation data from the ultra-high temperature region (\u3e 2000K). The study then compared the accuracy of the Deep Learning potentials to predict not only the ground-state properties, such as the elastic constants and the phonon dispersion curves but also the ultra-high temperature properties, including the lattice parameters and melting behaviors
Investigation of the Impact of Hypochlorous Acid on Adherence and Proliferation of Human Osteoblast Cells
No full textThis work explores hypochlorous acid as an antimicrobial treatment to prevent infection in compound fractures. Compound fractures are a type of fracture in which there is an open wound near the site of bone fracture, that is usually caused by bone protruding through the skin, leading to increased chance of contamination. The treatment of compound fractures begins with operative irrigation in the attempt to minimize infectious complications caused by contamination. Osteoblasts, bone forming cells that play a role in fracture treatment, will be exposed to products used in irrigation. If hypochlorous acid is to be considered as a treatment to improve the outcome of compound fractures, the safety of HOCl and osteoblasts must be determined. The first aim of this project will be to generate a cell culture in which commercially purchased osteoblast cells will be able to survive in an in vitro setting to allow for experimentation. The second aim of this research will involve the introduction of hypochlorous acid in various concentrations to cultures of osteoblasts to determine the cell survivability. To determine the concentration at which the cells will be able to survive, a constant number of cells will be introduced to various concentrations of hypochlorous acid, and a cell count will be performed following incubation. It was found that hypochlorous acid did not negatively impact osteoblast survivability or decrease proliferation
Menagerie Pains
No full textIn my creative thesis, readers follow Toddus as he accomplishes different tasks set out by the prince he serves, Prince Dinnax. My critical introduction examines the use of a hero in both my book and Redwall, by Brian Jacques, through the three steps of a hero’s journey outlined in Joseph Campbell’s The Hero with a Thousand Faces. Campbell’s steps can be found in almost every book published, even non-adventure books. After following the steps, I examine my own choice of hero. Toddus is a personal guard to a prince, and as such does not carry a lot of power. Jeff Vandermeer’s craft book, Wonderbook, gives instructions on how to determine and follow through with a main character. I compare the two princes in Captive Prince, by C.S. Pacat, and their autonomy or lack thereof with that of Prince Dinnax. Toddus is the hero setting out on his adventure because Dinnax is constrained by his title and duties attached to it