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2022

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A Digital Twin For Synchronized Multi-Laser Powder Bed Fusion (M-Lpbf) Additive Manufacturing, Shayna Petitjean Jan 2022

A Digital Twin For Synchronized Multi-Laser Powder Bed Fusion (M-Lpbf) Additive Manufacturing, Shayna Petitjean

Browse all Theses and Dissertations

One of the technological challenges in the widespread application of additive manufacturing is the formation of undesired material microstructure and defects. Specifically, in metal additive manufacturing, the microstructural formation of columnar grains in Ti-6Al-4V is common and results in anisotropic mechanical properties and a reduction in properties such as ductility and endurance limit. This work presents the application of hexagonal and circular arrays of synchronized lasers to alter the microstructure of Ti-6Al-4V in favor of equiaxed grains. An anisotropic heat transfer model obtains the temporal/spatial temperature distribution and constructs the solidification map for various process parameters, including laser power, laser …

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Automatically Generating Searchable Fingerprints For Wordpress Plugins Using Static Program Analysis, Chuang Li Jan 2022

Automatically Generating Searchable Fingerprints For Wordpress Plugins Using Static Program Analysis, Chuang Li

Browse all Theses and Dissertations

This thesis introduces a novel method to automatically generate fingerprints for WordPress plugins. Our method performs static program analysis using Abstract Syntax Trees (ASTs) of WordPress plugins. The generated fingerprints can be used for identifying these plugins using search engines, which have support critical applications such as proactively identifying web servers with vulnerable WordPress plugins. We have used our method to generate fingerprints for over 10,000 WordPress plugins and analyze the resulted fingerprints. Our fingerprints have also revealed 453 websites that are potentially vulnerable. We have also compared fingerprints for vulnerable plugins and those for vulnerability-free plugins.

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Detection Of Benzotriazole And Related Analogues In Surface Samples Collected Near An Ohio Airpark, Clara Leedy Jan 2022

Detection Of Benzotriazole And Related Analogues In Surface Samples Collected Near An Ohio Airpark, Clara Leedy

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Benzotriazoles are a class of contaminant of emerging concern which are commonly used as anticorrosive agents in aircraft deicer and anti-icing fluids (ADAFs). The analogues 1H-benzotriazole (BTZ), 4-methyl-1H-benzotrizole (4m-BTZ), and 5-methyl-1H-benzotriazole (5m-BTZ) are commonly found in environmental occurrence together. The two methylated isomers, collectively known as tolytriazole (TTZ), have different toxicity and stability. These contaminants are highly water soluble and resistant to biodegradation, making them persistent through water treatment. Benzotriazoles have been detected worldwide; this investigation focuses on monitoring three sites near a small airpark in Wilmington, Ohio. Two sites that receive runoff from the airpark, Lytle Creek and Indian …

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Vertebrate Assemblages Of The Skelley Limestone (Conemaugh Group : Carboniferous, Gzhelian) In Noble And Muskingum Counties, Ohio, Daniel Austin Cline Jan 2022

Vertebrate Assemblages Of The Skelley Limestone (Conemaugh Group : Carboniferous, Gzhelian) In Noble And Muskingum Counties, Ohio, Daniel Austin Cline

Browse all Theses and Dissertations

Three outcrops of the Gzhelian-aged Skelley Limestone (Casselman Formation, Conemaugh Group) were explored for vertebrate macrofossils and vertebrate microremains. The purpose of this exploration was to construct a better ecological history of the marine communities in the Late Pennsylvanian of eastern Ohio. Bulk limestone samples were collected, washed with acid, sieved and the resulting residues produced 21 distinct taxa of near-shore marine vertebrates. Osteichthyans were represented by an unknown palaeonisciform, an unknown platysomid, and an unknown palaeoniscoid. Holocephalians were represented by symmoriforms, helodontiforms, cochliodontiforms, and petalodontiforms. Elasmobranch groups included ctenacanthiforms and euselachians which contained representatives of hybodontiforms, protacrodontiforms, and neoselachians. …

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Semantics-Driven Abstractive Document Summarization, Amanuel Alambo Jan 2022

Semantics-Driven Abstractive Document Summarization, Amanuel Alambo

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The evolution of the Web over the last three decades has led to a deluge of scientific and news articles on the Internet. Harnessing these publications in different fields of study is critical to effective end user information consumption. Similarly, in the domain of healthcare, one of the key challenges with the adoption of Electronic Health Records (EHRs) for clinical practice has been the tremendous amount of clinical notes generated that can be summarized without which clinical decision making and communication will be inefficient and costly. In spite of the rapid advances in information retrieval and deep learning techniques towards …

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Development Of Enhanced User Interaction And User Experience For Supporting Serious Role-Playing Games In A Healthcare Setting, Mark Lee Alow Jan 2022

Development Of Enhanced User Interaction And User Experience For Supporting Serious Role-Playing Games In A Healthcare Setting, Mark Lee Alow

Browse all Theses and Dissertations

Education about implicit bias in clinical settings is essential for improving the quality of healthcare for underrepresented groups. Such a learning experience can be delivered in the form of a serious game simulation. WrightLIFE (Lifelike Immersion for Equity) is a project that combines two serious game simulations, with each addressing the group that faces implicit bias. These groups are individuals that identify as LGBTQIA+ and people with autism spectrum disorder (ASD). The project presents healthcare providers with a training tool that puts them in the roles of the patient and a medical specialist and immerses them in social and clinical …

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Behavior Of 3d Printed Polymeric Triply Periodic Minimal Surface (Tpms) Cellular Structures Under Low Velocity Impact Loads, Jesse James Leiffer Jan 2022

Behavior Of 3d Printed Polymeric Triply Periodic Minimal Surface (Tpms) Cellular Structures Under Low Velocity Impact Loads, Jesse James Leiffer

Browse all Theses and Dissertations

Surface-based lattice structures such as triply periodic minimal surface (TPMS) lattices are lightweight structures that are widely being investigated for applications in automotive, aerospace, military, railway, and naval structures. Due to the recent advent of three-dimensional (3D) printing (3DP) technologies, architected cellular materials such as surface- or strut-based periodic lattice cell structures have emerged as a unique class of lightweight metamaterials. These materials possess enhanced strength to weight ratio, high stiffness, exceptional capabilities in reducing noise and vibration, insulating heat, and effective impact energy absorption. Understanding the impact behavior of such materials are important so that they can be reliably …

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Growing Small: Citizen Preferences For New Development In Highland County, Virginia, And The Town Of Monterey, Charles F. Wilson Jan 2022

Growing Small: Citizen Preferences For New Development In Highland County, Virginia, And The Town Of Monterey, Charles F. Wilson

Master of Urban and Regional Planning Capstone Projects

“Growing Small: Citizen Preferences for New Development in Highland County, Virginia and the Town of Monterey” is a plan by Charles Wilson for Highland County (“Highland”) as they reconsider the future of the Town of Monterey (“Monterey”). Highland is a rural county in western Virginia at the intersection of U.S. Routes 250 and 220. In the Summer of 2021, a new Family Dollar was issued permits to demolish an historical lodging facility and construct a new store—just a few buildings away from an existing Dollar General. This was not without controversy, but ultimately prompted reflection amongst community members for how …

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A Comparison Of Stacking Methods To Estimate Survival Using Residual Lifetime Data From Prevalent Cohort Studies, Zhaoheng Li Jan 2022

A Comparison Of Stacking Methods To Estimate Survival Using Residual Lifetime Data From Prevalent Cohort Studies, Zhaoheng Li

Mathematics, Statistics, and Computer Science Honors Projects

Prevalent cohort studies are widely used for their cost-efficiency and convenience. However, in such studies, only the residual lifetime can be observed. Traditionally, researchers rely on self-reported onset times to infer the underlying survival distribution, which may introduce additional bias that confounds downstream analysis. This study compares two stacking procedures and one mixture model approach that uses only residual lifetime data while leveraging the strengths of different estimators. Our simulation results show that the two stacked estimators outperform the nonparametric maximum likelihood estimator (NPMLE) and the mixture model, allowing robust and accurate estimations for underlying survival distributions.

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Comparative Study Of High Order Methods For Subsonic Turbulence Simulation With Stochastic Forcing, Alexei G. Kritsuk, H. C. Yee, Björn Sjögreen, Dmitry Kotov Jan 2022

Comparative Study Of High Order Methods For Subsonic Turbulence Simulation With Stochastic Forcing, Alexei G. Kritsuk, H. C. Yee, Björn Sjögreen, Dmitry Kotov

United States National Aeronautics and Space Administration: Publications

A class of spatially seventh-order nonlinear filter methods with adaptive dissipation control developed by Yee & Sjögreen [1, 2] is tested on three-dimensional subsonic turbulence simulations with stochastic forcing. The Euler equations are solved using the Strang operator splitting of the homogeneous part of the equations and the stochastic forcing term, with an ODE solver used to integrate the latter. Both Ducros et al. and Kennedy-Gruber skew-symmetric split formulations of the inviscid flux derivatives are considered to minimize the use of numerical dissipation. The nonlinear filter methods are shown to be numerically stable for this application at least up to …

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Fasst: Fetal Alcohol Spectrum Support Training An Educational Program To Teach Foster And Adoptive Parents About Fetal Alcohol Spectrum Disorder, Carolyn Matthews Jan 2022

Fasst: Fetal Alcohol Spectrum Support Training An Educational Program To Teach Foster And Adoptive Parents About Fetal Alcohol Spectrum Disorder, Carolyn Matthews

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Fetal Alcohol Spectrum Disorder (FASD) is an umbrella term for a group of diagnoses that result from exposure to alcohol in utero. Alcohol creates a spectrum of impacts on the developing brain, contributing to lifelong physical, cognitive and behavioral implications. The prevalence of children with FASD in the foster care system is approximately 60 per 1000 children (Lange et al., 2013). Prevalence rates are underestimated due to children not being diagnosed or receiving an alternative diagnosis. This relates to various emotional, behavioral, social, and cognitive struggles for children and their families. To best serve this population and their families, it …

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Effects Of Lipin1 Deficiency & Restoration In The Dystrophic Diaphragm, Alexandra Brown Jan 2022

Effects Of Lipin1 Deficiency & Restoration In The Dystrophic Diaphragm, Alexandra Brown

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Duchenne Muscular Dystrophy (DMD) is an X-linked recessive disorder that is characterized by severe and progressive muscle wasting (Venugopal & Pavlakis, 2021). This disease is caused by a mutation in the largest known human gene which encodes the protein, dystrophin (Gao & McNally, 2015). Dystrophin connects the inner cytoskeleton to the extracellular matrix and is critical for maintaining the structural stability of muscle cells during contraction (Venugopal & Pavlakis, 2021). Mutations to the dystrophin gene result in myocyte membrane instability, contributing to the structural deterioration of the muscle tissue (Venugopal & Pavlakis, 2021). Progressive muscle degeneration and the replacement of …

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Analytical-Based Methods For Studying The Interaction Of Human Red Blood Cells With Noble Metal Nanoparticles, Praveen Kumar Alla Jan 2022

Analytical-Based Methods For Studying The Interaction Of Human Red Blood Cells With Noble Metal Nanoparticles, Praveen Kumar Alla

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With the advent of nanotechnology, the potential applications of nanoscale gold in medicine have expanded substantially. Gold’s therapeutic and toxic properties have been widely studied; however, little is known regarding gold’s contribution to oxidative stress in red blood cells (RBCs). This is especially true for recently designed large (L) gold nanorods (GNRs), which possess unmatched theranostic capabilities. Here, we report on the effect of LGNRs at the level of cellular function, and particularly on ion transport and the glutathione (GSH) concentration in human (H) RBCs. Gold has been hypothesized to effectively react with RBCs sulfhydryl groups, thereby causing depletion of …

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Deep Understanding Of Technical Documents : Automated Generation Of Pseudocode From Digital Diagrams & Analysis/Synthesis Of Mathematical Formulas, Nikolaos Gkorgkolis Jan 2022

Deep Understanding Of Technical Documents : Automated Generation Of Pseudocode From Digital Diagrams & Analysis/Synthesis Of Mathematical Formulas, Nikolaos Gkorgkolis

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The technical document is an entity that consists of several essential and interconnected parts, often referred to as modalities. Despite the extensive attention that certain parts have already received, per say the textual information, there are several aspects that severely under researched. Two such modalities are the utility of diagram images and the deep automated understanding of mathematical formulas. Inspired by existing holistic approaches to the deep understanding of technical documents, we develop a novel formal scheme for the modelling of digital diagram images. This extends to a generative framework that allows for the creation of artificial images and their …

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Guest Editorial: Introduction To Aoir 2021 Papers On Emerging Ethical Practices And Platform Challenges, Michael Zimmer Jan 2022

Guest Editorial: Introduction To Aoir 2021 Papers On Emerging Ethical Practices And Platform Challenges, Michael Zimmer

Computer Science Faculty Research and Publications

No abstract provided.

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A Low-Cost Machine Learning Based Network Intrusion Detection System With Data Privacy Preservation, Jyoti Fakirah, Lauhim Mahfuz Zishan, Roshni Mooruth, Michael L. Johnstone, Wencheng Yang Jan 2022

A Low-Cost Machine Learning Based Network Intrusion Detection System With Data Privacy Preservation, Jyoti Fakirah, Lauhim Mahfuz Zishan, Roshni Mooruth, Michael L. Johnstone, Wencheng Yang

Annual ADFSL Conference on Digital Forensics, Security and Law

Network intrusion is a well-studied area of cyber security. Current machine learning-based network intrusion detection systems (NIDSs) monitor network data and the patterns within those data but at the cost of presenting significant issues in terms of privacy violations which may threaten end-user privacy. Therefore, to mitigate risk and preserve a balance between security and privacy, it is imperative to protect user privacy with respect to intrusion data. Moreover, cost is a driver of a machine learning-based NIDS because such systems are increasingly being deployed on resource-limited edge devices. To solve these issues, in this paper we propose a NIDS …

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Human-Controlled Fuzzing With Afl, Maxim Grishin, Igor Korkin, Phd Jan 2022

Human-Controlled Fuzzing With Afl, Maxim Grishin, Igor Korkin, Phd

Annual ADFSL Conference on Digital Forensics, Security and Law

Fuzzing techniques are applied to reveal different types of bugs and vulnerabilities. American Fuzzy Lop (AFL) is a free most popular software fuzzer used by many other fuzzing frameworks. AFL supports autonomous mode of operation that uses the previous step output into the next step, as a result fuzzer spends a lot of time analyzing minor code sections. By making fuzzing process more focused and human controlled security expert can save time and find more bugs in less time. We designed a new module that can fuzz only the specified functions. As a result, the chosen ones will be inspected …

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The Amorphous Nature Of Hackers: An Exploratory Study, Kento Yasuhara, Daniel Walnycky, Ibrahim Baggili, Ahmed Alhishwan Jan 2022

The Amorphous Nature Of Hackers: An Exploratory Study, Kento Yasuhara, Daniel Walnycky, Ibrahim Baggili, Ahmed Alhishwan

Annual ADFSL Conference on Digital Forensics, Security and Law

In this work, we aim to better understand outsider perspectives of the hacker community through a series of situation based survey questions. By doing this, we hope to gain insight into the overall reputation of hackers from participants in a wide range of technical and non-technical backgrounds. This is important to digital forensics since convicted hackers will be tried by people, each with their own perception of who hackers are. Do cyber crimes and national security issues negatively affect people’s perceptions of hackers? Does hacktivism and information warfare positively affect people’s perception of hackers? Do individual personality factors affect one’s …

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Development And Validation Of A Force Measuring Device For A Laboratory Wave Tank, Jacob K. Colling Jan 2022

Development And Validation Of A Force Measuring Device For A Laboratory Wave Tank, Jacob K. Colling

Dissertations, Master's Theses and Master's Reports

The ability to predict the hydrodynamic force exerted on floating bodies plays a critical role in creating more effective control strategies for wave energy converters (WECs). Developing a test apparatus capable of directly measuring the forces exerted on a floating body subjected to a wavefield provides the means to validate theoretical prediction methods with experimental results and to develop data-based prediction methods for hydrodynamic forces. This report will discuss the development and validation of a device that measures the total vertical force exerted on a test artifact. The device requirements and design are discussed to examine the factors taken into …

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Word Games For Education: Investigating The Effectiveness Of Adding Elaboration Tasks To Crosswords For Learning Technical Vocabulary, Warat Khaewratana Jan 2022

Word Games For Education: Investigating The Effectiveness Of Adding Elaboration Tasks To Crosswords For Learning Technical Vocabulary, Warat Khaewratana

Dissertations, Master's Theses and Master's Reports

One challenge in STEM education is the learning of technical terms. In order to reason about higher-order scientific concepts, knowledge of technical vocabulary is often a prerequisite. Improving this knowledge may enhance the learning of higher-order concepts because it reduces cognitive load students experience while learning. To that end, we need innovative learning-aid tools that help students not only in learning and remembering technical terms, but also in applying the learned knowledge to broader concepts. This dissertation investigates the hypothesis that learning gained from crosswords can be used to teach technical terms. Furthermore, I am also examining the hypothesis that …

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Machine Learning-Driven Surrogate Models For Electrolytes, Tong Gao Jan 2022

Machine Learning-Driven Surrogate Models For Electrolytes, Tong Gao

Dissertations, Master's Theses and Master's Reports

We have developed a lattice Monte Carlo (MC) simulation based on the diffusion-limited aggregation model that accounts for the effect of the physical properties of ionic liquids (ILs) on lithium dendrite growth. Our simulations show that the size asymmetry between the cation and anion, the dielectric constant, and the volume fraction of ILs are critical factors to significantly suppress the dendrite growth, primarily due to substantial changes in electric-field screening. Specifically, the volume fraction of ILs has the optimal value for dendrite suppression. The present simulation method indicates potential challenges for the model extension to macroscopic systems. Therefore, we also …

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Stability Approximation Method For Pulse Loads In Power Electronic Systems, Eduardo A. Marmol D Jan 2022

Stability Approximation Method For Pulse Loads In Power Electronic Systems, Eduardo A. Marmol D

Dissertations, Master's Theses and Master's Reports

Pulse loads on power electronic distribution systems are becoming very popular nowadays as the components of ships and airplanes are moving to more electric power. However, the pulse loads have a destabilizing effect on the power distribution system. Usually, the method used to study the stability of this type of system are small-signal analyses and are based on a system where the load is modeled as a constant. Since DC-DC systems with pulsed loads are very nonlinear, a small-signal analysis does not provide helpful information related to the stability of the system. The work presented in this thesis focuses on …

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A Study Of Inverter-Based Resources On Power Grid Operation Under Uncertain Operating Conditions, Manisha Maharjan Jan 2022

A Study Of Inverter-Based Resources On Power Grid Operation Under Uncertain Operating Conditions, Manisha Maharjan

Electrical and Computer Engineering

The electric power grid is undergoing a rapid change predominantly driven by high penetration levels of renewable energy resources (RERs) such as wind and solar. These resources are interfaced with the power grid through power electronic inverters that use control algorithms to define their performance characteristics. As a group, these types of resources are commonly referred to as inverter-based RERs (IB-RERs). While IB-RERs use power electronic controls to change active and reactive power injection, the fast inverter controls, separating the power source from the grid, have changed grid dynamics and posed new challenges to maintaining reliable and safe grid operation. …

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A Narrative Review And Longitudinal Data Analysis Method To Evaluate The Association Between Head And Neck Cancer And Obstructive Sleep Apnea, Toan Le Jan 2022

A Narrative Review And Longitudinal Data Analysis Method To Evaluate The Association Between Head And Neck Cancer And Obstructive Sleep Apnea, Toan Le

Biomedical Engineering

The pathophysiological mechanisms of obstructive sleep apnea (OSA) and head and neck cancers (HNCs) have not been fully investigated. Currently, investigating the relationship between HNCs and OSA is incomplete due to the restriction of histological, molecular, and clinical evidence. In this research, the first section reviews the common course of therapy in patients with HNCs and OSA, the causal relationship and association between HNCs and OSA, and the scope of statistical methods used to investigate the association between HNCs and OSA. According to the observation from the literature review, more rigorously designed studies with longitudinal data collection should be considered. …

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Noise Reduction Of Tunable Resistive Pulse Sensing For Improved Extracellular Vesicles Profiling In Cancer Detection, Nega Ejjigu Jan 2022

Noise Reduction Of Tunable Resistive Pulse Sensing For Improved Extracellular Vesicles Profiling In Cancer Detection, Nega Ejjigu

Biomedical Engineering

EVs have much potential as sensitive, novel biomarkers because they represent the status of their cells of origin and can be used to detect cancer earlier than alternative biomarkers. The size of EVs can be determined by tunable resistive pulse sensing (TRPS). However, TRPS is susceptible to environmental noise, including mechanical and electrical noise that limits detection precision. To overcome these noises, an external device was designed, guided by flow simulations, to reduce noises that interfere with TRPS measurements. Both mechanical and electrical environmental noise reductions were observed after using the shield. The study also validated the noise reduction function …

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A Biological And Chemical Approach To Restoring Water Quality: A Case Study In An Urban Eutrophic Pond, Levi J. Mckercher, Tiffany L. Messer, Aaron R. Mittelstet, Steve D. Comfort Jan 2022

A Biological And Chemical Approach To Restoring Water Quality: A Case Study In An Urban Eutrophic Pond, Levi J. Mckercher, Tiffany L. Messer, Aaron R. Mittelstet, Steve D. Comfort

School of Natural Resources: Faculty Publications

Efforts to improve water quality of eutrophic ponds often involve implementing changes to watershed management practices to reduce external nutrient loads. While this is required for long-term recovery and prevention, eutrophic conditions are often sustained through the recycling of internal nutrients already present within the waterbody. In particular, internal phosphorus bound to organic material and adsorbed to sediment has the potential to delay lake recovery for decades. Thus, pond and watershed management techniques are needed that not only reduce external nutrient loading but also mitigate the effects of internal nutrients already present. Therefore, our objective was to demonstrate a biological …

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Natural Environment: Protocol To Recover Pollen Grains On Bodies, Karl J. Reinhard, A. Barbosa Jan 2022

Natural Environment: Protocol To Recover Pollen Grains On Bodies, Karl J. Reinhard, A. Barbosa

School of Natural Resources: Faculty Publications

No abstract provided.

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Automated Approaches For The Early-Stage Distinguishing Of Palmer Amaranth From Waterhemp, Akhil Venkataraju Jan 2022

Automated Approaches For The Early-Stage Distinguishing Of Palmer Amaranth From Waterhemp, Akhil Venkataraju

Communication

Palmer amaranth is an invasive pigweed species, possessing rapid growth, posing a threat to the economy of crops including corn. Its early detection and mitigation are of utmost importance; however, it is visually similar to waterhemp in the early growth stages. In this study, automated approaches are employed to distinguish palmer amaranth from waterhemp, within two weeks after emergence, from their RGB images. Morphological characteristics of these weeds are estimated and fed to several Machine Learning (ML) models. To improve classification accuracy, RGB images are augmented, and a Convolutional neural network is trained on 16000 images. Validated on images embedded …

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Evaluation Of The Relationship Between Size, Feeding Behavior, And Feed Efficency In Beef Cattle, Macie Mosher Jan 2022

Evaluation Of The Relationship Between Size, Feeding Behavior, And Feed Efficency In Beef Cattle, Macie Mosher

Animal Sciences

Feed efficiency in cow-calf operations can be influenced by multiple environmental and physiological factors. The current study examined the association between body size (weight, frame score, and volume), linear body measurements, and feeding behavior with different measures of feed efficiency in multiparous lactating beef cows. Prediction models for dry matter intake in cows using linear body measurements were also developed. Our findings indicate that body size measurements and feeding behavior may influence measures of efficiency. The inclusion of body measurements in prediction models of intake may serve as accurate and feasible methods for estimating intake of cows on farm. The …

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Examining Thieno[3,4-B]Pyrazine Through A Multifaceted Lens: From Extended Ring Functionalization To Ambipolar-Acceptor Copolymers, Evan Culver Jan 2022

Examining Thieno[3,4-B]Pyrazine Through A Multifaceted Lens: From Extended Ring Functionalization To Ambipolar-Acceptor Copolymers, Evan Culver

Chemistry and Biochemistry

A class of materials known as conjugated polymers (CPs) has been shown to integrate the physical properties of organic plastics such as low-weight, flexibility, and synthetic modularity with electronic semiconducting properties typically found in inorganic materials. While a variety of parameters determine the resultant material’s conductivity, a crucial factor is the bandgap (Eg). Specifically, thieno[3,4-b]pyrazine (TP) has found success in generating low Eg CPs (i.e. Eg < 1.5 eV), largely in part due to its ambipolar identity. Two strategies to achieve Eg values < 1 eV include extending the conjugation of TP through ring fusion and pairing TP with strong electron accepting moieties. The investigation into extended ring TPs as low bandgap homopolymers was initially pursued with the synthesis of poly(acenaphtho[1,2-b]thieno[3,4-e]pyrazine), a record setting low Eg homopolymer. Upon this realization of driving Eg¬ values down through ring fusion on the pyrazine portion of TP, additional analogues were considered with 2λ4δ2-dithieno[3,4-b:3’,4’-e]pyrazine as one of the most promising candidates due to its predicted Eg of 0.14 eV. Efforts into this research have produced a variety of precursors and analogues, adding to the family of TPs for further study. A second strategy for Eg reduction is through the pairing of electronically mismatched units known as donors and acceptors. While this does reduce Eg, the underlying principles of the cause is disputed. Thus, to further understand the interactions in these types of copolymer systems, a small molecule study was designed with a strong donor, a strong acceptor, and the ambipolar unit TP in which six possible dimer configurations were synthesized and analyzed to determine the extent of donor-acceptor interactions. Lastly, an investigation into TP-acceptor alternating copolymers was carried out by pairing TP with two acceptors of varying accepting strength and contributions to polymer solubility. Because of the atypical design of these copolymers, a relatively new cross-coupling method known as direct arylation polymerization was used in their synthesis. The optimization of which produced a CP with an Eg of 0.93 eV. These results thus provide evidence for a new design motif for low bandgap CPs that further refines our understanding of donor-acceptor relationships.

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