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Preclassic Cultural Eutrophication Of Lake Petén Itzá, Lowland Guatemala, By The Early Maya Of Nixtun-Ch'ich', Brooke A. Birkett Jan 2021

Preclassic Cultural Eutrophication Of Lake Petén Itzá, Lowland Guatemala, By The Early Maya Of Nixtun-Ch'ich', Brooke A. Birkett

Masters Theses

"Paleolimnological evidence indicates the ancient Maya transformed lowland terrestrial ecosystems by felling forest vegetation to construct large civic-ceremonial centers and expand agriculture. The effects of prehistoric Maya land alterations on lake trophic status, however, remain poorly understood. We analyzed a 515-cm-long sediment core from Lake Petén Itzá, lowland Guatemala, to infer paleoenvironmental changes resulting from Maya occupation of the riparian archaeological site of Nixtun-Ch'ich'. Substantial increases in charcoal and fecal stanol concentrations indicate Maya occupation of the Candelaria Peninsula by the late Early Preclassic period beginning ca. 1400 cal yr Before the Common Era (hereafter BCE), despite scant archaeological evidence …


Predator Scent And Presence Alter Mammal Assemblages In The Missouri Ozarks, Usa, Cara Jean Yocom-Russell Jan 2021

Predator Scent And Presence Alter Mammal Assemblages In The Missouri Ozarks, Usa, Cara Jean Yocom-Russell

Masters Theses

"Species that are vulnerable to predation exhibit a host of behavioral and physiological adaptations toward the avoidance of this outcome: Heightened awareness of surroundings through visual, olfactory, and auditory senses are common ways in which these species avoid detection by predators. While links between direct predator-prey relationships are well established, less is known about how predators can shape overall community structure or the populations of secondary or less frequently consumed prey items. As humans expand into rural areas, the frequency of wildlife conflicts rises. In response, humans look to prevent these events with a variety of methods. One such method …


The Validation Of Predicted Biological Age Of Drosophila Melanogaster From Combined Statistical Modeling, Lauren Francis Jan 2021

The Validation Of Predicted Biological Age Of Drosophila Melanogaster From Combined Statistical Modeling, Lauren Francis

Masters Theses

"Sleep is essential for maintaining a healthy body and mind and is associated with aging and aging related diseases. There are individual differences in fly as well as human sleep behavior and lifespan. Between and within individuals, sleep varies in characteristics including consolidation, rhythmicity, continuity, duration, and more. Various evidence in the literature suggests there are many molecular pathways involved with aging and they may be different for individuals. Our research is interested in a possible restorative mechanism of sleep and the ramifications of that mechanism to aging. We have developed two predictive models of aging using the fruit fly …


In Vitro And In Vivo Response To A Novel Borophosphate Bioactive Glass, Nada Abokefa Jan 2021

In Vitro And In Vivo Response To A Novel Borophosphate Bioactive Glass, Nada Abokefa

Masters Theses

"Bioactive glasses have been widely used in several biomedical and tissue engineering applications since the late 1960s. Numerous families of bioactive glasses have emerged over the years, with each having its own advantage and disadvantage. One concern common to all families is that most bioactive glasses create a basic or acidic environment when degraded and, therefore, are toxic for cells. Recently, there has been an increased interest in borophosphate bioactive glass (BPBGs) because of their neutral pH, release of therapeutic ions, and biodegradable properties. Despite the growing interest, there is little reported on the bioactivity of BPBGs. The biological effects …


Spatiotemporal Observations Of Water Stress In Kansas Winter Wheat And Corn From Remotely Sensed Evapotranspiration And Ndwi, Lindi Diane Oyler Jan 2021

Spatiotemporal Observations Of Water Stress In Kansas Winter Wheat And Corn From Remotely Sensed Evapotranspiration And Ndwi, Lindi Diane Oyler

Masters Theses

"Optimizing water use is a growing concern, especially in agricultural communities where water use is high. An important challenge in agricultural water optimization is knowing when and where crop water stress is occurring, particularly on large scales where in-situ measurements are no longer practical to obtain. In an effort to combat this challenge, this study utilizes remotely sensed evapotranspiration (ET) and Normalized Difference Water Index (NDWI) to evaluate the responses of integrated satellite datasets to water-stressed conditions over fields of irrigated corn, irrigated winter wheat, and rainfed winter wheat from 2007 to 2017 in southwestern Kansas. Using two different ET …


Neural Network Supervised And Reinforcement Learning For Neurological, Diagnostic, And Modeling Problems, Donald Wunsch Iii Jan 2021

Neural Network Supervised And Reinforcement Learning For Neurological, Diagnostic, And Modeling Problems, Donald Wunsch Iii

Masters Theses

“As the medical world becomes increasingly intertwined with the tech sphere, machine learning on medical datasets and mathematical models becomes an attractive application. This research looks at the predictive capabilities of neural networks and other machine learning algorithms, and assesses the validity of several feature selection strategies to reduce the negative effects of high dataset dimensionality. Our results indicate that several feature selection methods can maintain high validation and test accuracy on classification tasks, with neural networks performing best, for both single class and multi-class classification applications. This research also evaluates a proof-of-concept application of a deep-Q-learning network (DQN) to …