Digital Commons Network^™

Potential Mechanisms Maintaining A Conspicuous Polymorphism In Eastern Mosquitofish (Gambusia Holbrooki), Katelyn Giltner

Theses

Genetic variation often precedes adaptation, so the mechanisms that maintain this variation are a central topic in evolutionary biology. Gambusia holbrooki, or eastern mosquitofish, possesses a rare polymorphism for melanistic coloration. Melanics and typical silver males were examined for differences in behavioral and physiological traits that may impact the persistence of the melanism trait. No differences in standard metabolic rate were found via closed-chamber respirometry, but a detour task indicated that melanic males possess greater cognitive flexibility. Effects of the social environment on stress and reproductive traits were also evaluated by pairing males and comparing cortisol levels and sperm quality …

Aerodynamic Losses Of Additively Manufactured Blades In Transonic Conditions With Different Surface Treatments, Chase Allen Herrin

Theses

Additive manufacturing (AM) allows the production of high strength and high temperature alloys to increase the operational temperature of turbines and other engine components. AM inherently has high surface texturing, inclusive of waviness due to the layering effect in the laser powder bed fusion (L-PBF) process, and roughness due to surface defects such as partially sintered powder, deep notches, and micro-cracks. This thesis investigates how different surface treatments affect the surface static pressure variations and wake aerodynamic loss characteristics for each blade. A supersonic transonic blow down wind tunnel with a linear cascade test section is used to acquire this …

Goes-16 Glm Optical Energy In The Inner Core Of Hurricane Ian During Two Rapid Intensification Periods, Kiahna Mollette

Theses

Tropical cyclone (TC) rapid intensification (RI) is difficult to forecast but is a crucial element of TC forecasts and impacts. How lightning evolves prior to and during RI is of interest to better understanding TC RI. Results have not found a consensus in the flash rates within the inner core of rapidly intensifying TCs, indicating that there is not an understanding of these processes. Using the optical energy, measured by satellite imagery, the lightning behavior is investigated during Hurricane Ian's two RI periods, the first with almost no lightning and the second with nearly constant lightning. Radar measurements indicate that …

Assessing The Mesoscale Variability And Rapid Tornadogenesis In The High-Shear/Low-Cape, Surging Qlcs In Northern Alabama On 01 April 2023, Joshua L. Huggins

Theses

On 01 April 2023, a severe QLCS impacted Northern Alabama during the PERiLS field campaign under High-Shear/Low-CAPE (HSLC) conditions, with CAPE below 1000 J/kg and 0-6 km wind shear exceeding 25 m/s. This study examines the mesoscale variability and tornadogenesis within the QLCS. Ceilometer and Radar Wind Profiler data indicated lowering cloud bases and shifts in the boundary layer winds. Surface analyses revealed a cold pool strength of -9◦C at the tornadogenesis location, with significant spatial variability. Storm Relative Helicity values decreased from nearly 900 to 350 m2/s2 by 0800 UTC. A lightning jump around 0756 UTC coincided with a …

Development Of A High Speed Differential Temperature Sensor For In Situ Estimations Of Cn2 In The Planetary Boundary Layer, Michael C. Yurovchak

Theses

The propagation of electromagnetic energy through the Earth’s atmosphere is significantly modulated by spatial variability of the refractive index structure function (Cn2). In situ estimates of vertical profiles of Cn2 in the boundary layer are critical for evaluating model predictions and ground-based remote sensing retrievals of Cn2. This thesis describes the development of a sensor system that produces high frequency measurements of differential temperature between two points in space separated by a distance of 0.3m using two 5 𝜇𝑚 diameter platinum resistance temperature sensors with 10-4K resolution. The platinum wire sensors are connected to two legs of a Wheatstone Bridge …

Grating Lobe Suppression Techniques In Sparse Linear And Planar Phased Array Antennas With Reconfigurable Phasor Elements, William M. Current

Theses

With the continual increase in the need for wireless communications, there comes a desire to decrease fabrication costs. One of the primary drivers for the cost of an antenna array is the actual number of antennas used. This number, however, can only be decreased so far for a fixed aperture area without causing undesired secondary main beams, grating lobes, to appear in the radiation pattern. This work aims to analyze the results of two methods for reducing these grating lobes in sparse, scanning phased array antennas. Both of these methods are based upon dual-mode antenna elements, as opposed to single-mode …

Physiological Effects Of Facial Expressions During Cognitive And Social Stress, Emily X. Sorrells

Theses

This study explored the dynamics of facial expressions during stress. This 2 X 2 (Facial Expression by Task) mixed design evaluated how smiling and grimacing affected physiological and self-report measures of cognitive and social stress. The study implemented continuous monitoring of electrodermal activity (EDA). Facial expression was manipulated between-subjects as a genuine smile or grimace using chopsticks in the mouth. Task was manipulated as a counterbalanced within-subjects as a cognitive stressor using the Paced Auditory Serial Addition Task (PASAT) and a social stressor using Cyberball. Time was analyzed as repeated measures of change from baseline of EDA. Participants provided ratings …

Characterization Of Thin-Walled W-24re Structures Fabricated Using Laser-Powder Bed Fusion, Madelyne Rushing

Theses

W-24Re is a refractory alloy used in high temperature applications due to its high melting point, recrystallization temperature, and tensile strength. Due to the high melting point, fabrication is more commonly achieved through powder metallurgy processing, which relies on diffusion. As the material is available as a powder, it is a good candidate for laser-powder bed fusion (L-PBF) processing. This study focuses on characterization of L-PBF of W-24Re thin-walled structures to determine the feasibility and primary failure mechanisms under tension compared to that of bulk W-24Re. A laser parameter set was developed, and samples were provided by Quadrus Corporation for …

Exploring Collegiate Athletes' Experiences With Cliques, Cora G. Dodson

College of Graduate Studies: Theses & Dissertations

A significant body of literature examines team processes as they relate to the team as a collective unit (Eys et al., 2019). However, smaller units present within a team, such as cliques or subgroups, warrant further scientific exploration and dissemination (Wagstaff & Martin, 2018). Existent literature on cliques in an athletic setting established that intra-team groups are inevitable, while also highlighting their emergence and formation, and their relative consequences at the team level (Martin, 2020; Wagstaff & Martin, 2018). Despite the scientific advancement at the group level, research concerning cliques is scarce. Therefore, the purpose of this qualitative study was …

The Distribution Of The Significance Level, Paul O. Monnu

College of Graduate Studies: Theses & Dissertations

Reporting the p-value is customary when conducting a test of hypothesis or significance. The likelihood of getting a fictitious second sample and presuming the null hypothesis is correct is the p-value. The significance level is a statistic that interests us to investigate. Being a statistic, it has a distribution. For the F-test in a one-way ANOVA and the t-tests for population means, we define the significance level, its observed value, and the observed significance level. It is possible to derive the significance level distribution. The t-test and the F-test are not without controversy. Specifically, we demonstrate that as sample size …

Resonant Ultrasound Spectroscopy(Rus) For Material Characterization Of Metal Am Parts, Malik Marks

College of Graduate Studies: Theses & Dissertations

Additive manufacturing (AM) has revolutionized the manufacturing industry by offering flexibility, customization, and rapid prototyping capabilities. However, ensuring the quality and reliability of AM parts remains a significant challenge due to variations in material properties and process parameters. The NDE method used in this study is Resonant Ultrasound Spectroscopy (RUS). This method was used to evaluate and understand its ability to detect internal voids and defects. Dog-bone samples were made using the 316L stainless steel alloy which were fabricated by powder bed fusion (PBF) AM technique at different processing conditions and post processing conditions. These samples were tested to find …

Testing Differential Predation As A Mechanism Of Color Polymorphism In A Cryptic Lizard., Justin A. Sanclemente

College of Graduate Studies: Theses & Dissertations

Selection via predation is a strong evolutionary force on small organisms, producing unique phenotypic adaptations. In cryptic species, different populations may exhibit color polymorphisms to better match multiple substrates or backgrounds. Here, I conducted a clay model study in the Ocala National Forest of Florida (USA) to test predation as a selective mechanism for color polymorphism in the Florida scrub lizard (Sceloporus woodi). Clay models were constructed to resemble light and dark morphs of S. woodi and placed on contrasting substrates in longleaf pine and Florida scrub stands. It is hypothesized Florida Scrub Jays (Aphelocoma coerulescens) …

An Evaluation Of Social Media Use And Its Association With Nutrition Behaviors Among Female Parents, Meredith St. Cyr

College of Graduate Studies: Theses & Dissertations

Recent studies have indicated that an unhealthy diet plays a role in the development of overweight and obesity, which are among the most severe public health challenges of the 21st century. One population that has become an emerging focus is female parents aged 21 – 35. Research has demonstrated that the transition to parenthood and the years following are often a turning point regarding developing obesity and that early effects on weight gain are likely to be cumulative and persistent. A unique characteristic of this population is their high utilization of social media. This study utilized a mixed methods study …

What’S Agape Love Got To Do With It?: Teaching With Courage, Passion, And Compassion In A Rural Elementary School In North Georgia, Jhanna Bryson

College of Graduate Studies: Theses & Dissertations

This dissertation explores the crucial role of love in teaching, specifically focusing on the content of a rural elementary school in North Georgia. Drawing on qualitative research and personal experiences of the author, as well as other teachers at the same school, this study examines how love, manifested through courage, passion, and compassion, can significantly impact teaching practices and positively influence student outcomes in challenging educational settings. Theoretically my dissertations draws upon three bodies of literature such as critical pedagogy, (e.g. Darder, 2007, 2009, 2015, 2016, 2018; Freire, 1987, 1998, 2000, 2019; Giroux, 2010, 2018; hooks, 1994, 2001), radical love, …

Concentration Effects Of Ytterbium(Iii) Ions On The Physical, Structural, Thermal, And Optical Properties Of Barium Phosphate Glasses, Richard Amesimenu

College of Graduate Studies: Theses & Dissertations

Ytterbium(III)-doped glasses are widely known for their application in near-infrared (NIR) lasers and nowadays attract attention for solar spectral conversion in photovoltaic cells. In this study, the effects of ytterbium(III) concentration on the physical, structural, optical, and thermal characteristics of Yb-doped phosphate glasses were investigated. The glasses were synthesized using the melt-quenching technique with nominal compositions of 50P₂O₅:(50 – xBaO):xYb₂O₃ (x = 0, 0.5, 1.0, 2.0, 3.0 and 4 mol%). The properties were then examined by density and related parameters, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier transform-infrared …

Correlates Of Celebrity Worship And Materialism, Caitlin T. Davis

Honors College Theses

The proposed study will further examine the relationship between celebrity admiration and narcissism. The proposed study will also examine the relationship of the variables to materialism. Finally, this study will examine how the extent to which one perceives themselves to be similar in some respect to their favorite celebrity correlates with the aforementioned variables. We expect that there will be positive relationships among the variables such that greater celebrity worship is associated with higher narcissism, materialism, and perceived similarity with one’s favorite celebrity.

Investigating The Relationship Between Inherited Geologic Framework And Saltwater Intrusion On St. Catherines Island, Georgia, Juliet Talaber, Jacque Kelly, Robert Vance

Honors College Theses

Since the late 1800s, the oldest cities on the Georgia coast have been withdrawing water from the confined Floridan Aquifer System. As the population has grown, a cone of depression has formed extending from Savannah, GA to St. Catherines Island, GA, a barrier island 50 km southeast of Savannah. On St. Catherines Island, the cone of depression has reversed the lateral and horizontal groundwater flow gradients causing saltwater intrusion into the Upper Floridan Aquifer from the Lower Floridan Aquifer through joints, faults, or solution collapse features. Previous studies from the southern and central areas of the island have found evidence …

Raman Microspectroscopy For Detection Of Oral Potentially Malignant Disorders Using Minimally Invasive Brush Biopsy Samples, Isha Behl

Doctoral

Oral cancer is one of the most common cancers worldwide. The current gold standard for screening and diagnosis of oral premalignant and cancerous lesions is histopathological examination. Subjectivity is a major limitation of this technique, however. Other diagnostic methods exist, but they are not sensitive enough for early detection of potentially malignant disorders (PMDs), as these methods are based on morphological changes, which can occur late in malignant transformation. Raman spectroscopy, on the other hand, can provide molecular level information of the biological sample, through unique vibrational fingerprints of molecules. This is advantageous over the gold standard method, as molecular …

Enabling Ai And Robotic Coaches For Physical Rehabilitation Therapy: Iterative Design And Evaluation With Therapists And Post-Stroke Survivors, Min Hun Lee, Daniel Siewiorek, Asim Smailagic, Alexandre Bernardino, Sergi Bermúdez I Badia

Research Collection School Of Computing and Information Systems

Artificial intelligence (AI) and robotic coaches promise the improved engagement of patients on rehabilitation exercises through social interaction. While previous work explored the potential of automatically monitoring exercises for AI and robotic coaches, the deployment of these systems remains a challenge. Previous work described the lack of involving stakeholders to design such functionalities as one of the major causes. In this paper, we present our efforts on eliciting the detailed design specifications on how AI and robotic coaches could interact with and guide patient’s exercises in an effective and acceptable way with four therapists and five post-stroke survivors. Through iterative …

Pre-Clinical Targets For Ischemic Brain Injury, Daniel Morgan

Peninsula Medical School Theses

Stroke is the second most common cause of disability worldwide, and 87% of strokes result from a blockage in the cerebral blood flow which results in ischemia. Injury to the myelinated axons located in white matter is observed in ischemic injuries but is generally underappreciated. Research has shown that there is extensive vesicular glutamate release during ischemia, causing excitotoxic injury to oligodendrocytes, resulting in demyelination. Glutamate receptor antagonists have been trialled in stroke patients but fall short due to adverse side effects from high dose preparations. Stroke is largely a disease of ageing, and may occur in the presence of …

Investor Reaction To Spacs' Voluntary Disclosures, Vincent Castellani, Karl A. Muller, K.J. Park

Research Collection School Of Accountancy

SPACs are formed to combine with and provide a private firm public trading status and a capital infusion. Firms that enter the public market through a SPAC combination are believed to possess greater voluntary disclosure discretion than traditional IPOs as they obtain their public trading status through a merger. Consistent with regulators’ concerns, recent research finds that SPACs use this discretion opportunistically by issuing optimistic guidance. This study examines how investors respond to these disclosures. We find that optimistic projections increase retail purchasing, which is higher than that of institutional purchasing. Additionally, we find that investors partially see through the …

Internal And Social Sources Shape Judgments About The Mental And Physical Nature Of An Experience, Jacinth Jia Xin Tan, Alexander Karan, Dolores Albarracin

Research Collection School of Social Sciences

Although humans are intuitive dualists, little is known about whether they hold lay beliefs about the origins or sources of their intuitive perceptions of what is physical and what is mental. Drawing on theories of the sources of phenomenological experiences, we examined if people hold beliefs about the internal and social origins of judments that their experiences are physical or mental. In Study 1, participants provided physical or mental judgments about a range of personal experiences, and reported relying on both internal (i.e., examining own body and thoughts) and social (i.e., observing others) sources as information for their judgments. To …

Leveraging Instagram To Enhance Self-Esteem: A Self-Affirmative Intervention Study And Multilevel Mediation Analysis, Shuna Shiann Khoo, Hwajin Yang, Wei Xing Toh

Research Collection School of Social Sciences

Although studies have consistently indicated that heavier use of social networking sites (SNS) perpetuates poorer self-esteem outcomes, no study has examined potential intervention methods that can yield positive effects from SNS use. We hypothesized that viewing one's Instagram profile would have self-affirmative effects on self-perception because the profile typically showcases curated instrumental positive aspects of self. Furthermore, these self-affirmative effects would indirectly improve state self-esteem via enhanced clarity of self-concept. To test our hypothesis, we designed an experimental intervention study where one group viewed their Instagram profile regularly, while another group viewed a neutral abstract art profile. Using multilevel latent …

The Effect Of Mere Presence Of Smartphone On Cognitive Functions: A Four-Level Meta-Analysis, Andree Hartanto, Verity Y. Q. Lua, K. T. A. Sandeeshwara Kasturiratna, Paye Shin Koh, Germaine Y. Q. Tng, Manmeet Kaur, Frosch Y. X. Quek, Jonathan L. Chia, Nadyanna M. Majeed

Research Collection School of Social Sciences

As smartphones have become portable and immersive devices that afford social, informational, and recreational conveniences unbounded by physical restrictions, most daily activities have become closely intertwined with the presence of smartphones. This constant presence of smartphones in daily activities, however, may be concerning as some studies have suggested that smartphones—even their mere presence—can be distracting and can impair cognitive outcomes. However, such findings have not been consistently observed. To reconcile mixed findings, the current meta-analysis synthesized 166 effect sizes drawn from 53 samples and 33 studies including 4,368 participants on the effect of mere presence of smartphone on cognitive functions. …

The Lumbar Stabilization Exercise And Balance Training In Low-Grade Degenerative Lumbar Spondylolisthesis - A Prospective, Clinical Trial, Yun-Chung Lin, Mei-Yun Liaw, Tsung-Hsun Yang, Ya-Ping Pong, Yan-Yuh Lee, Chien-Wei Chen, Song-Chung Chen, Yu-Chi Huang

Rehabilitation Practice and Science

BACKGROUND: Patients with degenerative lumbar spondylolisthesis (DLS) may have low back pain (LBP), radicular pain and spinal instability. Current programs emphasize intervention of spinal stabilization exercise. However, no prospective, randomized studies have elucidated standardized treatment for DLS.

OBJECTIVE: To examine the effect of spinal stabilization exercise and Biodex balance system (BBS) training in patients with DLS.

METHODS: It was a prospective, clinical trial. Participants were allocated into three groups: (1) DLS-balance group treated with balance training (DLSB), (2) DLS non-balance training group (DLSNB), and (3) lumbar spondylosis without spondylolisthesis (SC). ALL patients underwent a rehabilitation program with lumbar stabilization exercises. …

Ultrasound-Guided Regenerative Injection For Carpal Tunnel Syndrome: A Narrative Review And Authors' Clinical Experience, Yung-Tsan Wu, King Hei Stanley Lam, Chueh-Hung Wu, Ke-Vin Chang, Wei-Ting Wu, Tyng-Guey Wang, Wen-Shiang Chen, Chih-Peng Lin, Kenneth Dean Reeves

Rehabilitation Practice and Science

Carpal tunnel syndrome (CTS) is the most common peripheral entrapment neuropathy but current conservative treatments are unsatisfactory. Recently, clinical trials using ultrasound-guided regenerative injection with 5% dextrose water or platelet-rich plasma have reported clinically and statistically significant benefits compared to current conservative treatments for the treatment of CTS. Regenerative injection for CTS is increasingly being utilized, proportional to the worldwide expansion of skills in the use of ultrasound guidance for precise injection and localization, and due to accumulating evidence that it enhances the success rate of conservative treatment, and reduces the rate of surgery. In this narrative review, our goals …

Atlantoaxial Rotatory Fixation Due To Congenital Strabismus: A Case Report, Chih-Ting Chen, Chia-Ling Lee

Rehabilitation Practice and Science

Background Atlantoaxial Rotatory Fixation (AARF) is a relatively rare condition, most diagnosed in the children, with common etiologies including minor trauma and upper respiratory infections. However, cases of AARF resulting from congenital strabismus are yet to be reported. Objective We aimed to underscore the uncommon association between AARF and congenital strabismus and to evaluate the effectiveness of halter traction. Method In this case report, we present an 11-year-old male patient with a history of congenital strabismus, which led to the development of AARF. Results The patient was initially observed to have torticollis and strabismus at the age of 4 months. …

Listening To The Voices Of America, Kathryn J. Edin, Corey D. Fields, David B. Grusky, Jure Leskovec, Marybeth J. Mattingly, Kristen M. Olson, Charles Varner

Department of Sociology: Faculty Publications

We make the case for building a permanent public-use platform for conducting and analyzing immersive interviews on the everyday lives of Americans. The American Voices Project (AVP)—a widely watched experiment with this new platform—provides important early evidence on its promise. The articles in this issue reveal that, although public-use interview datasets obviously cannot meet all research needs, they do provide new opportunities to study small or hidden populations, new or emerging social problems, reactions to ongoing social crises, submerged values and attitudes, and many other aspects of American life. We conclude that a permanent AVP platform would help build an …

Display Of Battery Items In Web And Mail Surveys: Grids Versus Item-By-Item And Radio Versus Wide Buttons, Kristen M. Olson, Jolene D. Smyth, Angelica Phillips

Department of Sociology: Faculty Publications

How to display questions that are part of a battery in self-administered surveys is an important decision. Battery items may be displayed in a grid in a mail survey or computer web survey, but are often displayed as individual items on mobile devices. Although past research has com-pared grids to item-by-item displays in computer and mobile web surveys, almost no work has compared these displays in mail surveys. Additionally, many web survey templates use wide rectangular buttons to select response options in individual items using a mobile-optimized design, different from the standard round answer space format typically used in mail …

Remember, You Can Complete This Survey Online! Web Survey Links And Qr Codes In A Mixed-Mode Web And Mail General Population Survey, Kristen M. Olson, Amanda Ganshert

Department of Sociology: Faculty Publications

Recruitment materials for concurrent mixed-mode self-administered web and mail surveys must communi-cate information about multiple modes simultaneously. Providing the link to the web survey on the cover of the paper questionnaire or including a QR code to access the web survey may increase the visibility of the web mode and thus increase the proportion of people who participate via the web, but whether including either piece of information does so has received surprisingly little empirical attention. In this paper, we exam-ine the results of experiments embedded in two general population probability-based concurrent mixed-mode surveys of Nebraska adults. First, in the …