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2023

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Two-Dimensional Nanomaterials And Nanocomposites For Sensing, Separation, And Energy Applications, Md Ashiqur Rahman Aug 2023

Two-Dimensional Nanomaterials And Nanocomposites For Sensing, Separation, And Energy Applications, Md Ashiqur Rahman

Theses and Dissertations

Two-dimension (2D) nanomaterials have gained popularity for the last few decades due to their excellent mechanical, electrical and thermal properties. These unique properties of 2D nanomaterials can be exploited in various applications specially in sensor, energy, and separation devices. In this study, the sensing and energy generation performance of PVDF/PAni fiber mat systems made by the forcespinning method with and without graphene coating. The graphene-coated nanocomposites show an average output voltage of 75 mV (peak-to-peak) which is 300% higher compared to bare fiber mats and an output current of 24 mA (peak-to-peak) by gentle finger pressing. Moreover, the graphene-coated PVDF/PAni …

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Manufacturing Of A Flexible Piezoelectric Nanogenerator By Functionalizing Polyvinylidene Fluoride With Lithium Tantalate And Multiwalled Carbon Nanotubes For Energy Harvesting And Sensing Applications, Islam Uddin Shipu Aug 2023

Manufacturing Of A Flexible Piezoelectric Nanogenerator By Functionalizing Polyvinylidene Fluoride With Lithium Tantalate And Multiwalled Carbon Nanotubes For Energy Harvesting And Sensing Applications, Islam Uddin Shipu

Theses and Dissertations

Mechanical energy is one of the readily accessible green energy sources that could be employed to meet the small-scale energy requirement. In order to capture mechanical energy, power the next generation of electronic gadgets, and health monitoring flexible piezoelectric nanogenerators made of light weight polymers and carbon nanotubes have drawn a lot of attention. Lithium tantalate (LiTaO3), a ferroelectric substance, was prepared here and utilized to create a flexible piezoelectric nanogenerator (FPNG). A compact piezoelectric nanogenerator that successfully transfers mechanical energy into electricity was then created using lightweight polyvinylidene fluoride (PVDF), multi-walled carbon nanotube (MWCNT), and LiTaO3 nanoparticles. To create …

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Fedbiometric: Image Features Based Biometric Presentation Attack Detection Using Hybrid Cnns-Svm In Federated Learning, S M Sarwar Aug 2023

Fedbiometric: Image Features Based Biometric Presentation Attack Detection Using Hybrid Cnns-Svm In Federated Learning, S M Sarwar

Theses and Dissertations

In the past few years, biometric identification systems have become popular for personal, national, and global security. In addition to other biometric modalities, facial and fingerprint recognition have gained popularity due to their uniqueness, stability, convenience, and cost-effectiveness compared to other biometric modalities. However, the evolution of fake biometrics, such as printed materials, 2D or 3D faces, makeup, and cosmetics, has brought new challenges. As a result of these modifications, several facial and fingerprint Presentation Attack Detection methods have been proposed to distinguish between live and spoof faces or fingerprints. Federated learning can play a significant role in this problem …

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Co-Flowering Community Effects On The Relative Contribution Of Pollen Quantity And Quality Limitation To The Reproductive Success Of Four Clarkia Species, Emma Moore Aug 2023

Co-Flowering Community Effects On The Relative Contribution Of Pollen Quantity And Quality Limitation To The Reproductive Success Of Four Clarkia Species, Emma Moore

Electronic Theses and Dissertations

More than 60% of plant populations experience low pollen availability which limits seed production (pollen limitation). Pollen limitation occurs due to low quantity or quality of pollen delivered to stigmas. Despite its ubiquity in nature, to date we still have limited understanding of the drivers of pollen limitation in plant communities. Plants typically occur in diverse communities where pollinator sharing is common and can influence quality and quantity aspects of pollen limitation. Co-flowering species can attract larger numbers of pollinators or they can compete for pollinators affecting pollen loads on stigmas. Pollinator competition may also lead to higher rates of …

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Understanding The Role Of Sabp2-Interacting Protein (Sip) 428: An Nad+-Dependent Deacetylase Enzyme In Abiotic Stress Signaling Of Nicotiana Tabacum, Mariam Onabanjo Aug 2023

Understanding The Role Of Sabp2-Interacting Protein (Sip) 428: An Nad+-Dependent Deacetylase Enzyme In Abiotic Stress Signaling Of Nicotiana Tabacum, Mariam Onabanjo

Electronic Theses and Dissertations

Abiotic stresses are constantly rising and pose a very high risk to global agricultural productivity and food security. Some plants have evolved several innate pathways for defense against these stresses. Hence, understanding stress signaling pathways can help develop crop plants with higher stress tolerance. The salicylic acid-mediated signaling pathway is important in plants experiencing biotic and abiotic stresses. In previous studies, SABP2-Interacting Protein (SIP-428) has been shown to be a negative regular of plant growth under abiotic stress. This study aimed to investigate the roles of SIP-428 in the ROS signaling of tobacco plants. We investigated transgenic RNAi-silenced lines of …

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“Just As Scared As I Am”: Daughters’ Perspectives Of The Impact Of The Overturning Of Roe V. Wade On Mother-Daughter Reproductive Conversations, Casadie Smith Aug 2023

“Just As Scared As I Am”: Daughters’ Perspectives Of The Impact Of The Overturning Of Roe V. Wade On Mother-Daughter Reproductive Conversations, Casadie Smith

Electronic Theses and Dissertations

Existing literature has identified mothers as the primary reproductive educators of their daughters and has determined mother-daughter conversations about reproduction to be an indicator of daughters’ sexual and reproductive behaviors. The overturning of Roe v. Wade on June 24, 2022, had an immediate impact on the reproductive lives of many people, including daughters. Through one-on-one interviews with 10 daughters, this qualitative study identifies three changes in mother-daughter reproductive conversations that were influenced by the overturning of Roe v. Wade: (a) The initiation of conversations, (b) the topics of conversations, and (c) the tone of these conversations. The results of this …

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Gratitude And Sleep Quality In Primary Care: Mediating Effects Of Health Self-Efficacy, Health Behaviors, And Psychopathology, Heather R. Altier Aug 2023

Gratitude And Sleep Quality In Primary Care: Mediating Effects Of Health Self-Efficacy, Health Behaviors, And Psychopathology, Heather R. Altier

Electronic Theses and Dissertations

Sleep disturbances are prevalent among primary care patients, and psychological dysfunction, including stress, anxiety, and depression, are robust contributors to poor sleep health. Yet, the presence of potential protective characteristics, such as health self-efficacy and engaging in adaptive health behaviors, may mitigate such outcomes. Gratitude (i.e., recognition and appreciation of experiences, relationships, and surroundings), a positive psychological cognitive-emotional characteristic, may serve as a catalyst of these beneficial downstream effects, given its association with improved health functioning and sleep. In a sample of primary care patients (N = 869) from 50 urban and 30 rural practices in Germany, health self-efficacy …

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Use Of Transposon Screening For Salicylic Acid-Assisted Desiccation Killing In Salmonella, Shannon D. Elliott Aug 2023

Use Of Transposon Screening For Salicylic Acid-Assisted Desiccation Killing In Salmonella, Shannon D. Elliott

Electronic Theses and Dissertations

Salmonella enterica serovar Typhimurium is one of the most prevalent food-borne pathogens, affecting millions around the world every year, making it a threat to global health. Salmonella possesses the ability to survive the normally lethal condition of desiccation, however, discovery of the genes and mechanisms behind this phenomenon are still ongoing. Using a transposon mutagenesis approach to construct a broad transposon library, this study aimed to uncover genes that may be contributing to changes in Salmonella’s survivability under desiccation, particularly when exposed to the antimicrobial molecule salicylic acid. Building on previous findings showing salicylic acid can alter cell viability …

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The Old Family Clock: Exploring High Variation Of Chronotype In The Common House Spider, Parasteatoda Tepidariorum, Caitlin Jones Aug 2023

The Old Family Clock: Exploring High Variation Of Chronotype In The Common House Spider, Parasteatoda Tepidariorum, Caitlin Jones

Electronic Theses and Dissertations

Circadian rhythms are often tightly confined around a mean of 24 hours with little variation in traditional model organisms in the absence of environmental time cues. Some spider species fall well outside this normal range with mean periods of 18 hours and variation around these means of 6 hours or more. This extreme variation in circadian rhythm is not well-understood and is the focus of the current study. Using Parasteatoda tepidariorum as a model organism, we investigated whether variation in eight circadian parameters could be explained by genetic variability, environmental conditions, or an endogenous feature of the circadian system of …

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Functional Morphology Of The Platyrrhine Humerus And Talus: Implications For Inferring Locomotor Behavior In Extinct Primates, Liam Michael Zachary Aug 2023

Functional Morphology Of The Platyrrhine Humerus And Talus: Implications For Inferring Locomotor Behavior In Extinct Primates, Liam Michael Zachary

Graduate Theses and Dissertations

Platyrrhines are a diverse radiation of primates that exhibit a range of locomotor adaptations. The relationships between extant primate locomotor behavior and variation in postcranial morphology are often used to make functional interpretations of skeletal anatomy in extinct primates. However, a comparative baseline of form-function relationships in the extant platyrrhine postcranium is lacking compared to other primates, which limits understanding of platyrrhine locomotor evolution. The humerus and talus are two of the best represented skeletal elements in the platyrrhine fossil record and are informative of locomotor behavior. Therefore, quantification of morphological variation in extant platyrrhine tali and humeri can provide …

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A Preliminary Characterization And Assessment Of Mesophotic Octocoral Microbiomes In The Western Gulf Of Mexico, Edward P. Gniffke Aug 2023

A Preliminary Characterization And Assessment Of Mesophotic Octocoral Microbiomes In The Western Gulf Of Mexico, Edward P. Gniffke

Theses and Dissertations

Mesophotic Coral Ecosystems are highly diverse and productive ecosystems in the western Gulf of Mexico which are composed of, in part, by octocorals (subclass Octocorallia). Despite their importance as foundational organisms octocorals are an understudied group in this region, with little known about their microbial community. Ninety-eight Octocoral samples collected from the western and northwestern Gulf of Mexico were sequenced using 16S rRNA sequencing to characterize their microbial communities. The sequenced microbiomes were generally low in diversity composed of a few core microbial taxa. Octocoral group was the main driver of microbiome composition as opposed to depth, season, region, and …

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A Novel Technique To Solve Fractional Differential Equations Using Fractional-Order B-Polynomial Basis Set, Md Habibur Rahman Aug 2023

A Novel Technique To Solve Fractional Differential Equations Using Fractional-Order B-Polynomial Basis Set, Md Habibur Rahman

Theses and Dissertations

This thesis uses B-Polynomial bases to solve both one-dimensional and multi-dimensional linear and nonlinear partial differential equations and linear and nonlinear fractional differential equations. The approach involves constructing an operational matrix from the terms of these equations using Caputo's fractional derivative of fractional B-polynomials. This leads to a semi-analytical solution derived from a matrix equation, and the results obtained using this method are compared to analytical and numerical solutions presented by other authors. The method is shown to be effective in calculating approximate solutions for various differential equations and provides a higher accuracy level than finite difference methods. This technique …

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Effect Of Pre-Growth Conditions On Foodborne Pathogen Survival Kinetics In Fresh Produce, Avninder Kaur Aug 2023

Effect Of Pre-Growth Conditions On Foodborne Pathogen Survival Kinetics In Fresh Produce, Avninder Kaur

Theses and Dissertations

World-wide consumption of fresh-cut produce has seen a dramatic increase over the past few decades. However, fresh-cut produce has been implicated in several illness outbreaks due to contamination with foodborne bacterial pathogens. Post-harvest contamination during handling and processing is considered rare but several influencing factors are often overlooked. Specifically, studies have reported the growth, survival, and death kinetics of foodborne bacterial pathogens such as E. coli O157: H7, Salmonella and Listeria monocytogenes in different fresh and fresh-cut produce. The effect of various factors such as storage temperature, time, and relative humidity are widely explored. It is increasingly evident that microbial …

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Simulating Motion Success With Muscle Deficiency In A Musculoskeletal Model Using Reinforcement Learning, Daniel Castillo Aug 2023

Simulating Motion Success With Muscle Deficiency In A Musculoskeletal Model Using Reinforcement Learning, Daniel Castillo

Theses and Dissertations

Humans possess an extraordinary ability to execute complex movements, captivating the attention of researchers who strive to develop methods for simulating these actions within a physics-based environment. Motion Capture data stands out as a crucial tool among the proven approaches to tackle this challenge. In this research, we explore the effects of decreased muscle force on the body's capacity to perform various tasks, ranging from simple walking to executing complex jumping jacks. Through a systematic reduction of the allowed force applied to individual muscles or muscle groups, we aim to identify the threshold at which the body's muscles tolerate the …

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Strategy-Specific Differentiation In Response To Resources And Drivers Of Spring Migration Phenology In Rocky Mountain Elk, Storm Crews Aug 2023

Strategy-Specific Differentiation In Response To Resources And Drivers Of Spring Migration Phenology In Rocky Mountain Elk, Storm Crews

Theses

Elk (Cervus canadensis) are known to exhibit high movement strategy diversity compared to other ungulate species. Most elk populations are migratory or partially migratory, presenting unique conservation and management challenges. For example, successful maintenance of multiple seasonal ranges and connectivity between them is necessary to conserve populations with migratory behaviors. Further study of the structure and maintenance of movement strategy diversity within partially migratory populations is needed to assist management and refine fundamental ecological theory. Improved understanding of the determinants of elk migratory timing is also important, with the dynamics of significant drivers likely to shift under future climate change …

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Understanding Natural Resource Conflicts As Causes And Consequences Of The Transition Towards Ecosystem Management: A Case Study Of The Shawnee National Forest In Southern Illinois, Usa, Nicole Mooar Aug 2023

Understanding Natural Resource Conflicts As Causes And Consequences Of The Transition Towards Ecosystem Management: A Case Study Of The Shawnee National Forest In Southern Illinois, Usa, Nicole Mooar

Theses

Since the 1980s, approaches to managing forest resources in the US and around the world have been shifting from the conventional sustained yield approach towards ecosystem management. Ecosystem management is a resource management paradigm that seeks to employ a collaborative and multidisciplinary approach to landscape scale conservation, as well as the integration of socio-economic and biophysical considerations with the overall goal of enhancing the health and resilience of coupled social-ecological systems. While the role of natural resource conflicts as drivers of the transition towards ecosystem management has received some research attention, the potential roles of ecosystem management in emerging natural …

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Isolation And Classification Of Green Alga Stigeoclonium Attenuatum And Evaluation Of Its Ability To Prepare Zinc Oxide Nanoflakes For Methylene Blue Photodegradation By Sunlight, Marwa A. Aubaeed, Amjed Mirza Oda, Emad Y.A. Al-Sultan Aug 2023

Isolation And Classification Of Green Alga Stigeoclonium Attenuatum And Evaluation Of Its Ability To Prepare Zinc Oxide Nanoflakes For Methylene Blue Photodegradation By Sunlight, Marwa A. Aubaeed, Amjed Mirza Oda, Emad Y.A. Al-Sultan

Baghdad Science Journal

Algae have been used in different applications in various fields such as the pharmaceutical industry, environmental treatments, and biotechnology. Studies show that the preparation of nanoparticles by a green synthesis method is a promising solution to many medical and environmental issues. In the current study, the green alga Stigeoclonium attenuatum (Hazen) F.S. Collins 1909 was isolated and identified from the Al-Hillah River (Governorate of Babylon) in the middle of Iraq. The green synthesis by the aqueous extract of algae was used to prepare the nanoflakes of ZnO. Nanoflakes of ZnO are characterized by X-Ray diffraction (XRD) and scanning electron microscope …

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On The Feasibility Of Machine Learning Algorithms Towards Low-Cost Flow Cytometry, Noah Vandal Aug 2023

On The Feasibility Of Machine Learning Algorithms Towards Low-Cost Flow Cytometry, Noah Vandal

Biomedical Engineering

Utilization low cost, scalable architectures for detection of specific cells for both mass flow and minute incidence analysis is something that is attractive for the clinical researcher, in order to expand access to otherwise costly devices. We demonstrate the use of a low-cost microfluidics device that performs detection of beads and cells, both for cell counting and for discrete cell type identification. This was accomplished using polymer technology via implementation of polydimethylsiloxane microfluidics, which were created by using a 3-D printed mold, and machine learning technologies with algorithms that can inference and track analyte particles within the microfluidic of interest. …

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Remote Robotic Surgery And Virtual Education Platforms: How Advanced Surgical Technologies Can Increase Access To Surgical Care In Resource-Limited Settings, Youmna A Sherif, Mohammed A Adam, Aimee Imana, Sarnai Erdene, Rachel W Davis Aug 2023

Remote Robotic Surgery And Virtual Education Platforms: How Advanced Surgical Technologies Can Increase Access To Surgical Care In Resource-Limited Settings, Youmna A Sherif, Mohammed A Adam, Aimee Imana, Sarnai Erdene, Rachel W Davis

Faculty, Staff and Students Publications

Advanced surgical technologies consist of remote and virtual platforms that facilitate surgical care and education. It also includes the infrastructure necessary to utilize these platforms (e.g., internet access, robotic systems, and simulators). Given that 5 billion people lack access to safe and timely surgical care, the appeal of these technologies to the field of global surgery lies primarily in its ability to eliminate geographical barriers and address surgeon shortages. This article discusses the use of virtual and remote technologies in resource-limited settings, the potential applications of these technologies, the possible barriers to their integration, and the impact these technologies may …

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Hydraulic Habitat Suitability For The Rio Grande Silvery Minnow At The Los Chavez Irrigation Outfall, New Mexico, Haley A. Ormsbee Aug 2023

Hydraulic Habitat Suitability For The Rio Grande Silvery Minnow At The Los Chavez Irrigation Outfall, New Mexico, Haley A. Ormsbee

Civil Engineering ETDs

It is essential to manage the Middle Rio Grande for aquatic species to preserve the native biodiversity of the river. During periods of low flow, endangered species such as the Rio Grande Silvery Minnow (RGSM) may get trapped in a drying reach without the ability to escape from isolated pools. Very little is known about how areas of refuge, such as irrigational outfall channels, buffer RGSM from stream flow intermittency. Hence, there is a crucial need to quantify available habitat for RGSM in areas of refuge. This study aims to make connections between flow regimes and physical-habitat conditions to help …

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Identification Of A Β-Arrestin-Biased Negative Allosteric Modulator For The Β2-Adrenergic Receptor, Michael Ippolito, Francesco De Pascali, Nathan Hopfinger, Konstantin E. Komolov, Daniela Laurinavichyute, Poli Adi Narayana Reddy, Leon A. Sakkal, Kyle Z. Rajkowski, Ajay P. Nayak, Justin Lee, Jordan Lee, Gaoyuan Cao, Preston S. Donover, Melvin Reichman, Stevens. An, Joseph M. Salvino, Raymond B. Penn, Roger S S. Armen, Charles P. Scott, Jeffrey L. Benovic Aug 2023

Identification Of A Β-Arrestin-Biased Negative Allosteric Modulator For The Β2-Adrenergic Receptor, Michael Ippolito, Francesco De Pascali, Nathan Hopfinger, Konstantin E. Komolov, Daniela Laurinavichyute, Poli Adi Narayana Reddy, Leon A. Sakkal, Kyle Z. Rajkowski, Ajay P. Nayak, Justin Lee, Jordan Lee, Gaoyuan Cao, Preston S. Donover, Melvin Reichman, Stevens. An, Joseph M. Salvino, Raymond B. Penn, Roger S S. Armen, Charles P. Scott, Jeffrey L. Benovic

Department of Biochemistry and Molecular Biology Faculty Papers

Catecholamine-stimulated β2-adrenergic receptor (β2AR) signaling via the canonical Gs–adenylyl cyclase–cAMP–PKA pathway regulates numerous physiological functions, including the therapeutic effects of exogenous β-agonists in the treatment of airway disease. β2AR signaling is tightly regulated by GRKs and β-arrestins, which together promote β2AR desensitization and internalization as well as downstream signaling, often antithetical to the canonical pathway. Thus, the ability to bias β2AR signaling toward the Gs pathway while avoiding β-arrestin-mediated effects may provide a strategy to improve the functional consequences of β2AR activation. Since attempts to develop Gs-biased agonists and allosteric modulators for the β2AR have been largely unsuccessful, here we …

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Role Of Endophytic Fungi On Arsenic Uptake In Solution: Insights For Bioremediation, Taylor Lillian Busch Aug 2023

Role Of Endophytic Fungi On Arsenic Uptake In Solution: Insights For Bioremediation, Taylor Lillian Busch

Civil Engineering ETDs

Hazardous metals mobilized from natural deposits and mining legacy are environmental and human health concerns. The waters of our partner Native American communities affected by uranium and gold mining legacy exceed the EPA MCL of 10 µg/L arsenic (As). Bioremediation is a novel technology that uses native resources to remediate metals in the soil and groundwater. Plant-fungi symbiosis for bioremediation is widely studied, but the role of endophytic fungi in metal uptake is not well understood. The objectives of this study are to 1) determine As uptake by symbiotic endophyte Cadophora sp. and little bluestem grass (Schizachyrium scoparium) …

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Influence Of Abiotic Drivers And Plant Community Interactions On Bald Cypress (Taxodium Distichum) Seedlings: Implications For Restoration, Victoria Ellis Aug 2023

Influence Of Abiotic Drivers And Plant Community Interactions On Bald Cypress (Taxodium Distichum) Seedlings: Implications For Restoration, Victoria Ellis

Biological Sciences Theses & Dissertations

Forested freshwater wetlands are valuable ecosystems that provide habitat for numerous species, sequester carbon, and act as sinks for excess water and nutrients. Historically, these ecosystems have been heavily degraded by anthropogenic activities leading to loss of ecosystem services and a desire to restore freshwater forested wetland habitat. Thus, science-backed approaches for the restoration of freshwater forested wetlands are necessary to ensure restoration goals are met. This body of research employed the Stress Gradient Hypothesis to test whether a multi-species planting approach using Juncus effusus (L.) (soft rush) could facilitate the survival of Taxodium distichum (L.) Rich. (bald cypress) seedlings …

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Effects Of Physical Characteristics Of Placebos On Exercise Performance, Owen Sipes Aug 2023

Effects Of Physical Characteristics Of Placebos On Exercise Performance, Owen Sipes

Human Movement Studies & Special Education Theses & Dissertations

Previous research has shown that placebos can impact medical conditions such as irritable bowel syndrome and depression as well as elicit analgesic effects and improvements in certain exercise performances. These placebo responses occur from a variety of alterations to the placebo itself or through verbal suggestion of how helpful the placebo will be. This study aimed to observe whether changing the color and quantity of capsules can induce improvements in both vertical jump and hand grip strength. This deceptive, parallel study consisted of 28 participants, with a mean age of 24.9 (±4.3) years old, that were randomly assigned to receive …

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The Impact Of Covid-19 Stressors, Racial Discrimination, And Racial Socialization On Family Functioning In Black Families, Regina L. Alexander Aug 2023

The Impact Of Covid-19 Stressors, Racial Discrimination, And Racial Socialization On Family Functioning In Black Families, Regina L. Alexander

Psychology Theses & Dissertations

Marginalized communities, specifically Black Americans, have been disproportionately impacted by the COVID-19 pandemic which has resulted in more hospitalizations and deaths within this particular community. However, this disproportionate impact of COVID-19 is likely the result of ongoing health disparities related to a lack of access to adequate healthcare. In addition to health disparities specifically related to COVID-19, Black Americans have also experienced public displays of racial discrimination resulting from the systemic racism that has occurred for many years. It has been determined that stress spillover can impact relationship factors and this same spillover may be an important factor by which …

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Examining The Relationship Between Spelling Achievement And Academic Achievement In Community College Students, Tambra Lee Riggs-Gutiérrez Aug 2023

Examining The Relationship Between Spelling Achievement And Academic Achievement In Community College Students, Tambra Lee Riggs-Gutiérrez

Educational Leadership & Workforce Development Theses & Dissertations

The relationship between spelling achievement and academic achievement in community college students was investigated in this quantitative study. The research questions focused on whether a brief (under 15 minutes) spelling screening assessment may or may not predict student academic achievement of course grade points earned in an entry-level English class or cumulative grade point average. Demographic and descriptive data were also analyzed. A linear regression analysis design was used in this study. Participants for the study were 55 students from two geographically distant campuses of one community college in the Commonwealth of Virginia in the Mid-Atlantic region of the United …

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Effects Of Chewing Time On Gastrointestinal Discomfort, Substrate Use, And Performance During Running, Thomas Geaney Aug 2023

Effects Of Chewing Time On Gastrointestinal Discomfort, Substrate Use, And Performance During Running, Thomas Geaney

Human Movement Studies & Special Education Theses & Dissertations

Previous research has shown that food particle size affects gastric processing. For example, food particles greater than 3 mm may delay gastric emptying under certain conditions. Delays in gastric emptying can be problematic during aerobic exercise, leading to nausea, bloating, fullness, and other gastrointestinal (GI) symptoms. In some cases, symptoms can be severe enough to negatively affect athletic performance. This study investigated the effects of manipulating chewing duration of carbohydrate sports bars on GI discomfort, physiological responses, and performance during endurance running. This crossover study recruited 12 male runners (age: 36.4 ± 7.2 years, VO2peak: 57.2 ± 4.7 …

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Evaluating Direct Filtration As An Alternative To Conventional Carbon-Based Advanced Treatment For Indirect Potable Reuse, Savannah M. Flemmer Aug 2023

Evaluating Direct Filtration As An Alternative To Conventional Carbon-Based Advanced Treatment For Indirect Potable Reuse, Savannah M. Flemmer

Civil & Environmental Engineering Theses & Dissertations

Hampton Roads Sanitation District (HRSD) is recharging purified wastewater into the Potomac Aquifer via the Sustainable Water Initiative for Tomorrow (SWIFT) project. Conventional SWIFT treatment applies coagulation, flocculation, sedimentation, ozonation, biofiltration, granular activated carbon (GAC) adsorption, and ultraviolet disinfection to secondary effluent to produce water that meets drinking water standards for managed aquifer recharge. HRSD is considering implementing direct filtration as an alternative to conventional treatment for two additional SWIFT facilities. Direct filtration presents an opportunity for significant cost savings by eliminating sedimentation, shortening flocculation detention time, and reducing coagulant usage. Without upstream removal of solids and organics, however, biofilters …

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Data-Driven Predictive Modeling To Enhance Search Efficiency Of Glowworm-Inspired Robotic Swarms In Multiple Emission Source Localization Tasks, Payal Nandi Aug 2023

Data-Driven Predictive Modeling To Enhance Search Efficiency Of Glowworm-Inspired Robotic Swarms In Multiple Emission Source Localization Tasks, Payal Nandi

Mechanical & Aerospace Engineering Theses & Dissertations

In time-sensitive search and rescue applications, a team of multiple mobile robots broadens the scope of operational capabilities. Scaling multi-robot systems (< 10 agents) to larger robot teams (10 – 100 agents) using centralized coordination schemes becomes computationally intractable during runtime. One solution to this problem is inspired by swarm intelligence principles found in nature, offering the benefits of decentralized control, fault tolerance to individual failures, and self-organizing adaptability. Glowworm swarm optimization (GSO) is unique among swarm-based algorithms as it simultaneously focuses on searching for multiple targets. This thesis presents GPR-GSO—a modification to the GSO algorithm that incorporates Gaussian Process Regression (GPR) based data-driven predictive modeling—to improve the search efficiency of robotic swarms in multiple emission source localization tasks. The problem formulation and methods are presented, followed by numerical simulations to illustrate the working of the algorithm. Results from a comparative analysis show that the GPR-GSO algorithm exceeds the performance of the benchmark GSO algorithm on evaluation metrics of swarm size, search completion time, and travel distance.

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Examining The Experience And Impact Of Teen-To-Teen Crisis Line Work For Youth Volunteers: A Pilot Study, Taylor Kalgren Aug 2023

Examining The Experience And Impact Of Teen-To-Teen Crisis Line Work For Youth Volunteers: A Pilot Study, Taylor Kalgren

Psychology Theses & Dissertations

For young people, suicide is a leading cause of death. In addition, suicidal thoughts and behaviors begin during adolescence, and rates are high during this developmental period. Crisis lines are one of the oldest suicide prevention strategies used today. Crisis line work is challenging, and therefore, examining the health and safety of these operators is critical. Teen-to-teen (t2t) crisis lines are a unique resource where adolescent volunteers help their similarity aged peers. The goal of this pilot study was to begin to evaluate the impact of t2t crisis lines for youth volunteers. Twenty youth crisis line volunteers (ages 15-20) were …

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