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2020

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Correlating In-Situ Monitoring Data With Internal Defects In Laser Powder Bed Fusion Additive Manufacturing, Andrew J. Harvey Jan 2020

Correlating In-Situ Monitoring Data With Internal Defects In Laser Powder Bed Fusion Additive Manufacturing, Andrew J. Harvey

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The presence of defects within laser powder bed fusion (LPBF) parts can lead to reduced mechanical properties and life of components. Because of this, the ability to detect these defects within the parts is critical before the part is subject to its intended loading. Normally the parts are subjected to a quality analysis once they are completed however, this process is typically expensive and time consuming. A solution for these problems is to sense the creation of defects and pores in the parts in-situ, while the part is being fabricated. One proposed method of in-situ monitoring is visible spectroscopy to …


Small-Signal Analysis Of Non-Isolated Ćuk Dc-Dc Converter, Lokesh Kathi Jan 2020

Small-Signal Analysis Of Non-Isolated Ćuk Dc-Dc Converter, Lokesh Kathi

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In the future, renewable energy sources will be the primary energy sources due to non-renewable energy resources depletion. Having a sustainable energy source as an input voltage source for the electrical system is essential. Its applications can be widely used in hybrid solar-wind energy systems, electric vehicles, etc. This converter is invented and named after by Slobodan Cuk. An analysis describing a detailed steady-state operation of the non-isolated Cuk converter operating in continuous-conduction mode (CCM) is provided. The expected steady-state current and voltage waveforms across different components of the converter are analytically derived. Design equations for the converter are provided. …


Design And Simulation Of Boost Dc - Dc Pulse Width Modulator (Pwm) Feed-Forward Control Converter, Calenia L. Franklin Jan 2020

Design And Simulation Of Boost Dc - Dc Pulse Width Modulator (Pwm) Feed-Forward Control Converter, Calenia L. Franklin

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Military aircraft systems’ power losses are occurring during the loading operations; loading and unloading causes the aircraft systems to lose power. The primary aircraft power source is provided by a 400Hz Ground Power Units (GPU). This GPU provides power to interior lighting, the aircraft cargo compartment, and other electrical systems (i.e. bus). The issues are during loading and unloading on the aircraft, which causes dropout of aircraft power supplied by the external 400Hz GPU. The majority of the military aircraft require a high voltage and a high current with a 270V power output. This thesis analyzes using Feed-Forward PWM Boost …


Improving Pain Management In Patients With Sickle Cell Disease Using Machine Learning Techniques, Fan Yang Jan 2020

Improving Pain Management In Patients With Sickle Cell Disease Using Machine Learning Techniques, Fan Yang

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Sickle cell disease (SCD) is an inherited red blood cell disorder that can cause a multitude of complications throughout a patient's life. Pain is the most common complication and a significant cause of morbidity. Since pain is a highly subjective experience, both medical providers and patients express difficulty in determining ideal treatment and management strategies for pain. Therefore, the development of objective pain assessment and pain forecasting methods is critical to pain management in SCD. On the other hand, the rapidly increasing use of mobile health (mHealth) technology and wearable devices gives the ability to build a remote health intervention …


Anthrax Event Detection: Analysis Of Public Opinion Using Twitter During Anthrax Scares, The Mueller Investigation, And North Korean Threats, Michele E. Miller Jan 2020

Anthrax Event Detection: Analysis Of Public Opinion Using Twitter During Anthrax Scares, The Mueller Investigation, And North Korean Threats, Michele E. Miller

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When people allow fear to drive their decision making, they often make decisions that do more harm than good. Examples of this include stocking up on ciprofloxacin, flooding doctors’ offices and buying black market antibiotics after the anthrax attacks of 2001. Therefore, it is important to be able to address what people are saying when another anthrax attack occurs. Supervised and unsupervised machine learning methodologies can be utilized to detect an event, classify the tweets by event, and to determine the main topics of discussion. Over the period of data collection, twenty events were detected. Three of these events concerned …


Global Joint Registry: Analysis Of Revision Hip Arthroplasty Data, Alicia M. Runser Jan 2020

Global Joint Registry: Analysis Of Revision Hip Arthroplasty Data, Alicia M. Runser

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Total hip arthroplasty (THA) has become well-known as being one of the most successful procedures with much long-term positive clinical results. However, revision surgeries are still required. The four most common failure modes for THAs, “reasons for revision”, are loosening, dislocation or instability, fracture, and infection. The goal of a hip arthroplasty register is to gather information on patients that undergo a total hip arthroplasty and factors pertaining to their surgery which may affect their outcome for future years such as the reason for revision. Analysis of this data can help with the allocation of healthcare funds and the efficacy …


Observing P300 Amplitudes In Multiple Sensory Channels Using Cognitive Probing, Cody Lee Wintermute Jan 2020

Observing P300 Amplitudes In Multiple Sensory Channels Using Cognitive Probing, Cody Lee Wintermute

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High cognitive workload occurs when excessive working memory resources have been deployed to resolve sensory and cognitive processing, resulting in decremented task performance. The P300 event-related potential (ERP) component has shown sensitivity to cognitive load, and it was hypothesized that an attenuated P300 amplitude could be indicative of high cognitive load. We tested this hypothesis by having eight participants complete two continual performance tasks at increasing workload levels while simultaneously performing an oddball task, evoking P300 ERPs in either the auditory or tactile sensory channel. In our experiment, electroencephalographic recordings were collected over the parietal region to observe the P300 …


Mitigating Atmospheric Phase Errors In Sal Data, Randy S. Depoy Jr. Jan 2020

Mitigating Atmospheric Phase Errors In Sal Data, Randy S. Depoy Jr.

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Synthetic aperture ladar (SAL) is an emerging remote sensing technology capable of providing high-resolution, interpretable, and timely imagery. SAL and synthetic aperture radar (SAR) are similar in that they provide high-resolution imagery suitable for a wide-variety of applications beyond the diffraction limit of the real aperture. Several advantages of SAL are; realistic imagery resulting from diffuse scattering of optically-rough objects, fine directionality of laser beam making the technology inherently low probability-of-detect, and shorter synthetic aperture collection times, all of which result from operating at optical as opposed to RF wavelengths. With the dramatic decrease in wavelength, SAL systems become more …


Kv2.1 Channel Clustering In The Sod1-G93a Mouse Model Of Als, Joshua Christopher Harris Jan 2020

Kv2.1 Channel Clustering In The Sod1-G93a Mouse Model Of Als, Joshua Christopher Harris

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Kv2.1 channels mediate slow-activating K+ rectifier current within the membrane of spinal motoneurons (MNs), and they are known to co-localize with other synapses and ion channels. Although Kv2.1 channels are suggested to regulate MN excitability, little research has gone into investigating its potential contribution to MN-altered excitability in Amyotrophic Lateral Sclerosis (ALS). Using the male SOD1-G93A mouse model of ALS, we examined Kv2.1 cluster area and density in lumbar MNs at four key stages of disease progression. In our experiments, MNs were separated by type via SK3 immunoreactivity in order to isolate and compare the responses of disease-resistant (slow; SK3+) …


Extracting Information From Subroutines Using Static Analysis Semantics, Luke A. Burnett Jan 2020

Extracting Information From Subroutines Using Static Analysis Semantics, Luke A. Burnett

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Understanding how a system component can interact with other services can take an immeasurable amount of time. Reverse engineering embedded and large systems can rely on understanding how components interact with one another. This process is time consuming and can sometimes be generalized through certain behavior.We will be explaining two such complicated systems and highlighting similarities between them. We will show that through static analysis you can capture compiler behavior and apply it to the understanding of a function, reducing the total time required to understand a component of whichever system you are learning.


Primary Processing Parameters And Their Influence On Porosity And Fatigue Life Of Additively Manufactured Alloy 718, Luke C. Sheridan Jan 2020

Primary Processing Parameters And Their Influence On Porosity And Fatigue Life Of Additively Manufactured Alloy 718, Luke C. Sheridan

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In many structural applications void-like defects cause significant performance debits which call for component redesign or post-processing to account for or remove the defects. For laser powder bed fusion (LPBF) processes, it has been shown that many of these features and their size and shape characteristics are controllable through LPBF process parameter manipulation. For design efforts, however, it is necessary to understand the direct influences of processing on the formation of porosity and the role that individual pores and porosity distributions have on the properties and performance of AM components. Additionally, design criteria must be established to facilitate implementation of …


Finding Data Races In Software Binaries With Symbolic Execution, Nathan D. Jackson Jan 2020

Finding Data Races In Software Binaries With Symbolic Execution, Nathan D. Jackson

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Modern software applications frequently make use of multithreading to utilize hardware resources better and promote application responsiveness. In these applications, threads share the program state, and synchronization mechanisms ensure proper ordering of accesses to the program state. When a developer fails to implement synchronization mechanisms, data races may occur. Finding data races in an automated way is an already challenging problem, but often impractical without source code or understanding how to execute the program under analysis. In this thesis, we propose a solution for finding data races on software binaries and present our prototype implementation BINRELAY. Our solution makes use …


Hierarchical Anomaly Detection For Time Series Data, Ryan E. Sperl Jan 2020

Hierarchical Anomaly Detection For Time Series Data, Ryan E. Sperl

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With the rise of Big Data and the Internet of Things, there is an increasing availability of large volumes of real-time streaming data. Unusual occurrences in the underlying system will be reflected in these streams, but any human analysis will quickly become out of date. There is a need for automatic analysis of streaming data capable of identifying these anomalous behaviors as they occur, to give ample time to react. In order to handle many high-velocity data streams, detectors must minimize the processing requirements per value. In this thesis, we have developed a novel anomaly detection method which makes use …


Development Of Embedded Atom Method Interatomic Potentials For Ge-Sn-Si Ternary And Constituent Binary Alloys For Modeling Material Crystallization, Sudip Acharya Jan 2020

Development Of Embedded Atom Method Interatomic Potentials For Ge-Sn-Si Ternary And Constituent Binary Alloys For Modeling Material Crystallization, Sudip Acharya

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Group IV elements based nanoelectronics devices (mainly Si and Ge based devices) have been developed and improved over a long period of time and are the most influencing materials of semiconductor electronics, but due to their indirect bandgap their use in optoelectronics is limited. Alternatively, new Group IV alloys comprised of Ge, Si, and Sn semiconductor materials have emerged as attractive options for various electronic and optoelectronic applications. The binary and ternary alloys provide strain and energy bandgap engineering by controlling element content, a route for realizing direct-transition semiconductors, improvement in interface and defect properties, and a reduction of the …


Characterization Of A Novel Terahertz Chemical Sensor, Daniel J. Tyree Jan 2020

Characterization Of A Novel Terahertz Chemical Sensor, Daniel J. Tyree

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A recently constructed novel analytical tabletop terahertz (THz) chemical sensor capable of detecting a wide range of gases with high sensitivity and specificity was characterized to assess its performance over a range of operational parameters. The sensor was designed with an objective of quantifying composition of exhaled human breath, where target concentrations span part per trillion (ppt) to part per billion (ppb) level of dilutions. The sensor utilizes terahertz rotational spectroscopy of sampled gases for quantification of dilutions. The sensor occupies a volume of ~ 2 ft3 and incorporates a coiled absorption cell, thermal desorption tubes, and all necessary electronic …


Influence Of Light Availability On Tree Growth, Defense, And Emerald Ash Borer (Agrlius Planipennis) Success In White Fringetree (Chionanthus Virginicus) And Black Ash (Fraxinus Nigra), Michael S. Friedman Jan 2020

Influence Of Light Availability On Tree Growth, Defense, And Emerald Ash Borer (Agrlius Planipennis) Success In White Fringetree (Chionanthus Virginicus) And Black Ash (Fraxinus Nigra), Michael S. Friedman

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White fringetree is a host for the invasive emerald ash borer (EAB) despite being lower quality than black ash. Observations suggest that host trees grown in full sun are more resistant to EAB than those grown in shade, however chemical defense mechanisms and the impact of environmental stress have not been assessed. We quantified constitutive and induced defenses and other characteristics white fringetree and black ash phloem tissue grown under differential light conditions, and these traits were related to EAB larval performance. White fringetree had significantly lower constitutive and induced activities of defense associated enzymes and lignin but higher phenolic, …


Exploring The Impact Of Affective Processing On Visual Perception Of Large-Scale Spatial Environments, Auroabah S. Almufleh Jan 2020

Exploring The Impact Of Affective Processing On Visual Perception Of Large-Scale Spatial Environments, Auroabah S. Almufleh

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This thesis explores the interaction between emotions and visual perception using large scale spatial environment as the medium of this interaction. Emotion has been documented to have an early effect on scene perception (Olofsson, Nordin, Sequeira, & Polich, 2008). Yet, most popularly-used scene stimuli, such as the IAPS or GAPED stimulus sets often depict salient objects embedded in naturalistic backgrounds, or “events” which contain rich social information, such as human faces or bodies. And thus, while previous studies are instrumental to our understanding of the role that social-emotion plays in visual perception, they do not isolate the effect of emotion …


Design And Implementation Of Simplified Sliding-Mode Control Of Pwm Dc-Dc Converters For Ccm, Humam A. Al-Baidhani Jan 2020

Design And Implementation Of Simplified Sliding-Mode Control Of Pwm Dc-Dc Converters For Ccm, Humam A. Al-Baidhani

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The pulse-width modulated (PWM) dc-dc converters play a vital role in several industrial applications that include motor drives, electric vehicles, dc distribution systems, and consumer electronics. The switched-mode power converters step the input voltage up or down based on their typology and provide a regulated output voltage. The stability and regulation performance of a power converter can tremendously be improved via a suitable control design. However, due to the nonlinearity of the power converters and the presence of the line and load disturbances, the design of a robust and low-cost control circuit becomes a challenging task. The sliding-mode control of …


Fate Of White Fringetree Through The Invasion Wave Of Emerald Ash Borer And Its Variation In Resistance To Attack, Emily A. Ellison Jan 2020

Fate Of White Fringetree Through The Invasion Wave Of Emerald Ash Borer And Its Variation In Resistance To Attack, Emily A. Ellison

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Ornamental white fringetrees in IL, IN, OH, and PA were reassessed in 2018 as a follow-up study to determine the fate of the white fringetree through the invasion wave of emerald ash borer. Attack rates decline by half from 2015-2018 and only 13% of trees were infested. Health of not reinfested trees in 2018 improved suggesting resilience against EAB attack whereas currently infested trees in 2018 displayed signs of declining health. Trees differed in their resistance to EAB attack and 41 additional ornamental and wild white fringetrees were studied in OH to determine if the anti-herbivory defense chemical, oleuropein, influenced …


Predicting Subjective Sleep Quality Using Objective Measurements In Older Adults, Reza Sadeghi Jan 2020

Predicting Subjective Sleep Quality Using Objective Measurements In Older Adults, Reza Sadeghi

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Humans spend almost a third of their lives asleep. Sleep has a pivotal effect on job performance, memory, fatigue recovery, and both mental and physical health. Sleep quality (SQ) is a subjective experience and reported via patients’ self-reports. Predicting subjective SQ based on objective measurements can enhance diagnosis and treatment of SQ defects, especially in older adults who are subject to poor SQ. In this dissertation, we assessed enhancement of subjective SQ prediction using an easy-to-use E4 wearable device, machine learning techniques and identifying disease-specific risk factors of abnormal SQ in older adults. First, we designed a clinical decision support …


Insulin-Like Growth Factor-1 (Igf-1) Impacts P53-Regulated Gene Products In Uvb-Irradiated Human Keratinocytes And Skin Epidermis, Abdulrhaman Mohammed Mohammed Alkawwar Jan 2020

Insulin-Like Growth Factor-1 (Igf-1) Impacts P53-Regulated Gene Products In Uvb-Irradiated Human Keratinocytes And Skin Epidermis, Abdulrhaman Mohammed Mohammed Alkawwar

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Skin cancer is the most prevalent human malignancy and is primarily caused by ultraviolet (UV) wavelengths of sunlight. However, the fact that most skin cancers occur in people over the age of 60 indicates that advantaged age is a second skin cancer risk factor. Why geriatric skin is prone to developing skin cancers is not clear, but several studies have shown that dermal fibroblasts in geriatric skin express lower levels of the hormone insulin-like growth factor-1 (IGF-1) than young adult skin and that deficient IGF-1 signaling negatively impacts how epidermal keratinocytes respond to UVB radiation. A major regulator of the …


Eye-Tracking To Evaluate Trust In Human-Atr Interaction, Samuel Francis Adelman Jan 2020

Eye-Tracking To Evaluate Trust In Human-Atr Interaction, Samuel Francis Adelman

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Human collaboration with targeting aids have allowed analysts to achieve a greater level of coordination and productivity in a variety of fields. This project investigates the impact that an Assisted Target Recognition (ATR) algorithm’s false alarm rate and the task Target of Interest (TOI) level has on user-system trust and use in a targeting decision task. Previous studies suggest that an increased number of false alarms in an ATR task negatively impacts analyst trust in the system. This study will further contribute to this research, aiming to provide a better framework for appropriate tolerance levels within ATR algorithms, utilizing pre-truthed …


Metal Coupon Testing In An Axial Rotating Detonation Engine For Wear Characterization, Gary S. North Jan 2020

Metal Coupon Testing In An Axial Rotating Detonation Engine For Wear Characterization, Gary S. North

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Rotating Detonation Engines (RDE) are being explored as a possible way to get better fuel efficiency for turbine engines than is otherwise possible. The walls of the RDE are subjected to cyclic thermal and mechanical shock loading at rates of approximately 3 KHz, with gas temperatures as high as 2976 K. This project performed testing with Inconel 625 and 304 stainless steel coupons in an RDE outer body to attempt to measure material ablation rates. Significant microstructural changes were observed to include grain growth in both alloys, carbide formation and grain boundary melting in Inconel, and formation of delta ferrite …


Assessing Implicit Leadership And Followership Theories, Daniel Bashore Jan 2020

Assessing Implicit Leadership And Followership Theories, Daniel Bashore

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Implicit Leadership and Followership Theories (ILTs and IFTs, respectively) are individuals’ schemas composed of attributes that characterize leaders and followers. ILTs and IFTs are commonly measured through direct measures, however, researchers have questioned the validity of popular direct measures. With better and more parallel measures, we can examine the extent to which individuals think about leaders and followers as similar or dissimilar. Also, although substantial research has examined predictors of explicit leadership and leaders’ behavior, little research has attempted to examine antecedents of implicit leadership or followership. Using a sample of working adults (N = 243), the current study created …


A Planarian Kinesin Associated Protein 3 Homolog Is Required For Spermatogenesis And Ciliogenesis, Donovan Christman Jan 2020

A Planarian Kinesin Associated Protein 3 Homolog Is Required For Spermatogenesis And Ciliogenesis, Donovan Christman

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Microtubule-based structures are an essential part of eukaryotic cells as they are involved in a number of processes such as phagocytosis, chromosome separation, intracellular transport, and cell motility. Transport along microtubules is accomplished by kinesin superfamily proteins (KIFs), which are motor proteins that bind cargo and use ATPase activity to move along microtubules in an anterograde fashion. One of the most common kinesin complexes is the heterotrimeric Kinesin 2 complex which is composed of KIF3 subunit dimers and the Kinesin Associated Protein 3 (KAP3). This complex is known as the KIF3 complex and functions along microtubules in cilia and flagella. …


What Are You Looking At? Using Eye-Tracking To Provide Insight Into Careless Responding, Cheyna Katherine Brower Jan 2020

What Are You Looking At? Using Eye-Tracking To Provide Insight Into Careless Responding, Cheyna Katherine Brower

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Careless responding (CR), also called insufficient effort responding (IER), occurs when survey participants respond to items without regard to item content. The presence of careless responding threatens the validity of inferences made from self-report data (Huang et al., 2012; Huang et al., 2015), thus careless responding must be identified and removed to trust inferences made based on self-report survey data. Using a sample of 59 undergraduate students, this study uses eye-tracking data to assess the validity of existing careless responding indices and to provide insight into the nature of careless responding. Although influenced by measurement error in the eye-tracking indices, …


An Approach To Cluster And Benchmark Regional Emergency Medical Service Agencies, Swetha Kondapalli Jan 2020

An Approach To Cluster And Benchmark Regional Emergency Medical Service Agencies, Swetha Kondapalli

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Emergency Medical Service (EMS) providers are the first responders for an injured patient on the field. Their assessment of patient injuries and determination of an appropriate hospital play a critical role in patient outcomes. A majority of states in the US have established a state-level governing body (e.g., EMS Division) that is responsible for developing and maintaining a robust EMS system throughout the state. Such divisions develop standards, accredit EMS agencies, oversee the trauma system, and support new initiatives through grants and training. But to do so, these divisions require data to enable them to first understand the similarities between …


Targeting Oncogenic K-Ras And Monoamine Oxidase B Utilizing Chalcones Bearing The 3,4,5-Trimethoxyphenyl Motif, Cody Fourman Jan 2020

Targeting Oncogenic K-Ras And Monoamine Oxidase B Utilizing Chalcones Bearing The 3,4,5-Trimethoxyphenyl Motif, Cody Fourman

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Oncogenic K-Ras is a driver protein found in specific cancers and was once thought to be “undruggable.” However, recent advances have suggested that mislocalizing K-Ras from the plasma membrane could be a viable strategy to target these cancers. The objective of this project was to identify a lead compound and determine a structure-activity relationship from chalcones bearing the 3,4,5-trimethoxy motif towards oncogenic K-Ras and MAO-B. This was accomplished by keeping the trimethoxy group consistent on one ring while varying the electron-donating or -withdrawing groups on the opposite ring. Previous work showed chalcones of this specific archetype exhibiting indiscriminate MAO inhibition, …


Effects Of Forest Age And Composition On Coleoptera Associated With Fungal Fruiting Bodies In Southwest Ohio, Jeffrey M. Brown Jan 2020

Effects Of Forest Age And Composition On Coleoptera Associated With Fungal Fruiting Bodies In Southwest Ohio, Jeffrey M. Brown

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Mature forests often harbor greater biodiversity than younger woods. As this relationship of forest age to biodiversity has not been examined for all taxa, this study sought to document the diversity of mycophilous beetle communities in deciduous forests of southwest Ohio and understand how they vary in relation to forest age. I surveyed fungus associated beetles using baited traps at eight forested sites in the Dayton, Ohio region. Traps were surveyed three times during 2018 to account for seasonal variation, something that has not been done for this geographic region. Forest age had no significant effect on beetle abundance or …


Composition Of Dung Beetle Communities In A Tropical Montane Forest Alters The Rate Of Dung Removal More Than Species Diversity Alone, Elizabeth A. Engle Jan 2020

Composition Of Dung Beetle Communities In A Tropical Montane Forest Alters The Rate Of Dung Removal More Than Species Diversity Alone, Elizabeth A. Engle

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Dung beetles provide key ecological functions by degrading and recycling dung. I used experimentally-assembled communities to examine the role of species richness, community biomass, species diversity, species identity, and community composition in dung removal, using Ateuchus chrysopyge, Copris nubilosis, Onothophagus cyanellus, and Dichotomius satanas. I hypothesized: (1) that as species richness, biomass, and diversity increases within a community, dung removal increases; and (2) species are not functionally equivalent, so community composition should influence dung removal rates. As species richness, biomass, and diversity of experimentally-assembled communities increased, the proportion of dung removed also increased. Also, the four species in this study …