Digital Commons Network^™

Diminishing Creative Returns: Predicting Optimal Creative Performance Via Individual Differences In Executive Functioning, Kent F. Hubert

Graduate Theses and Dissertations

A robust finding in creativity research is that during idea generation, later (vs. earlier) responses on a divergent thinking task tend to be more creative, while the number of responses start off quickly, and then slow down over time, termed the serial order effect. Divergent thinking and time may follow a diminishing returns curve, where there is an optimal amount of time that should be spent while generating ideas. Executive functions (inhibition, updating, and shifting) have been associated with divergent thinking, specifically with the idea generation phase, but the effect of individual differences on the temporal dynamics of divergent thinking …

In Vitro And In Vivo Evaluation Of Antimicrobial Activity, Oocyst Sporulation Rate, Oocyst Integrity And Oocyst Infectivity In Eimeria Maxima M6 Oocyst Suspensions Treated With Chlorhexidine Salts In Comparison With Potassium Dichromate, Lauren Laverty

Graduate Theses and Dissertations

Eimeria species oocysts cause coccidiosis, one of the costliest diseases in the poultry industry. Coccidiosis infections cause significant economic losses due to reduced performance in chickens and turkeys. The objective of this thesis was to determine fecal bacterial recovery from chlorhexidine (CHX) salt suspensions containing Eimeria maxima M6 oocysts and evaluate the effect of CHX salts on oocysts during long-term cold storage. For bacterial recovery experiments, CHX digluconate and CHX gluconate were tested at different concentrations on poultry fecal slurries during oocyst shedding. Eimeria maxima M6 oocysts were evaluated in CHX salt suspensions to test the effect on oocyst degradation …

Stream Restoration Effectiveness In Mullins Creek In Fayetteville, Arkansas, Amadeo Scott

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Lotic waterways are vital for habitat, food, water, and flood protection, but urbanization poses a major threat to their integrity. Runoff from urban surfaces leads to pollution, flashiness, loss of biodiversity, and other symptoms, also known as Urban Stream Syndrome (USS). To combat USS, streams can be restored, but most restorations are not monitored so their long-term effectiveness is unknown. This study quantitatively evaluated a decade-old stream restoration in Fayetteville, Arkansas, to assess its effectiveness in combating USS and achieving set restoration goals, and to gain insights for future restoration projects. Restoration goals included decreasing erosion and sedimentation, increasing pool …

Postpartum Visitation Policies, Jenna B. Holderman, Morgan E. Matthews

The Eleanor Mann School of Nursing Undergraduate Honors Theses

Background: Continual support for the birthing person during labor improves delivery outcomes and overall childbirth experiences. How many support people are present and their relation to the birthing person varies based on individual preference, family dynamics, and sociocultural expectations. During the Covid-19 pandemic, many hospitals implemented a one-visitor policy for deliveries. With these new guidelines in place, the length of hospital stays significantly decreased, and there were a variety of opinions towards these restrictions.

Purpose: The purpose of this study was to explore birthing persons’ overall sentiment towards visitors in the immediate postpartum period.

Methods: The current study analyzed …

Examining Task-Related Differences In The Error-Related Negativity (Ern) As A Function Of Cognitive Control Strategy And Trait Anxiety, Russell Mach

Graduate Theses and Dissertations

Anxiety disorders pose a significant challenge to daily living, workplace productivity, and healthcare systems. Extant research supports empirical links between anxiety and brain-level error monitoring. The ERN – or error-related negativity – is one widely studied correlate of anxious symptomatology. Relatively stable individual differences in the ERN are inferred from electroencephalogram (EEG) recordings time-locked to the commission of mistakes. However, the assumed interchangeability of ERNs elicited under different experimental conditions has not been thoroughly evaluated. Canonical tasks for measuring the ERN may cue specific strategies for cognitive control, possibly producing divergent findings across studies. In a sample of 108 undergraduate …

Effect Of Onion Peel Bioactive Compounds On Gut Microbiome Of Obese Adults, Saad Al-Din Sifat

Graduate Theses and Dissertations

Obesity, a pervasive global health concern, involves a complex interplay between genetic factors, dietary patterns, and the gut microbiota. Onion peels are rich in polyphenols and known for their antioxidant properties. However, the effects of in-vitro digested onion peel extract has not been investigated thus far. This study therefore assesses the effects of digested bioactive compounds from onion peels, emphasizing gut microbiota shift and metabolites. Onion peel extract (OPE), digested onion peel extract (DOPE), and solid-phase-extracted digested onion peel extracts (SPE-DOPE) were analyzed for total phenolic content (TPC) and antioxidant activity. SPE-DOPE exhibited the highest TPC and antioxidant activity. Fecal …

Solar Cooking Solutions For Haiti, Isaac Mergner

Graduate Theses and Dissertations

This study focuses on enhancing the efficiency of solar cooking through the use of solar cookers and heat retention boxes. The research involved testing various cooking vessels and lids in a solar cooking experiment, with a specific focus on the performance of different materials and their heat retention capabilities. The experiment aimed to increase the efficiency of solar cookers, which are popular in developing nations due to their relatively low cost. The findings indicate that the combination of a solar cooker and a heat retention box can significantly improve the cooking process, particularly in areas with limited access to cooking …

A Framework Of Flow Models For The Development And Testing Of Cardiovascular Devices, Megan Laughlin

Graduate Theses and Dissertations

Cardiovascular disease (CVD) is the leading cause of death worldwide and its treatment continues to improve due to the advancement of innovative cardiovascular medical devices. In vitro and in silico models serve to replicate the in vivo environment for the development and testing of these devices prior to using animals for testing, and eventually humans in clinical trials. However, limitations related to these models exist in multiple areas including general, cardiac, and venous applications. Specifically, current gaps have been identified with customizable, tissue-mimicking phantoms (general), 2D Blood Speckle Imaging (BSI) (cardiac) and a bioprosthetic venous valve (venous). This dissertation focuses …

Understanding The Kinetics Of Laser-Induced Nanowelding Of Nanoparticles And The Motility Of Bacteria When Faced With Obstacles, Ariel Rogers

Graduate Theses and Dissertations

This dissertation has two focus areas: nanoparticle nanowelding and bacteria motility in the presence of micrometer sized structures. There are two main projects for the nanoparticle nanowelding studies: “Real-time imaging of laser-induced nanowelding in solution” and “Two-color laser-induced nanostructure shape modulation.” For the real-time imaging project, I used a fluorescence microscope, a 405 nm laser, and various python packages to quantify the average size of nanowelded nanostructures as a function of time and found that the average nanostructure growth over time fit the parameters of A¯(t) ∝ c0(1−e−t/τ), where c0 represents the initial concentration of nanoparticles in the solution and …

Exploring The Interrelationships Among Structural Complexity, Multi-Trophic Biodiversity, And Ecosystem Productivity In Forested Ecosystems., Ayanna St. Rose

Graduate Theses and Dissertations

Forests play a pivotal role in sustaining global biodiversity and mitigating the global climate, as they serve as the primary refuge for terrestrial biodiversity and effectively capture and store atmospheric carbon dioxide. However, changing climate and land use are altering the geographic distribution, physical structure, and productivity of forested ecosystems that can have profound impacts on biodiversity conservation, forest productivity, and global climate. This dissertation contributes to our understanding of multifaceted interactions between the physical and biological structural complexity and ecosystem functions in forested landscapes across the United states by using openly available data from two national networks: the National …

Bayesian Learning Of Spatiotemporal Source Distribution For Beached Microplastic In The Gulf Of Mexico, David Pojunas

Graduate Theses and Dissertations

Over the last several decades, plastic waste has gradually accumulated while slowly degrading in terrestrial and oceanic environments. Recently, there has been an increased effort to identify the possible sources of plastic to understand how they affect vulnerable beaches. This issue is of particular concern in the Gulf of Mexico due to the presence of oil, natural gas, and plastic production. In this thesis, we expand upon existing Bayesian plastic attribution models and develop a rigorous statistical framework to map observed beached microplastics to their sources. Within this framework, we combine Lagrangian backtracking simulations of floating particles using nurdle beaching …

Tissue-Engineered Models For Investigating Nerve Infiltration In Fibrotic Microenvironments, Nikolas Ala-Kokko

Graduate Theses and Dissertations

Neuron infiltration is involved in a multitude of diseased states and is critical in the regeneration of physiologic conditions. Modeling of innervation in three-dimensional, heterogenous, environments would allow early investigation in the crosstalk of neurons and native cells in normal and pathophysiologic microenvironments to gain an understanding of mechanistic functions. This would allow for greater insight into the role of metabolism, cell adhesion, microenvironmental alternations, cellular crosstalk, and signaling pathways that play a role in the promotion and prevention of neurite growth. In this thesis, with the construction of collagen-based hydrogels as the foundation for cell culture, we investigate cell …

Health Beneficial Effects Of Black Raspberry, Blueberry, And Blackberry Volatile Extracts In Lung And Colon, Inah Gu

Graduate Theses and Dissertations

Berries are one of the most consumed fruits in our diet, and rich in dietary fiber, vitamins, minerals, polyphenols, and volatiles. Volatiles are responsible for the aroma of berries, and are widely used in food, perfumery, and cosmetic industries. However, the potential health beneficial effects of berry volatiles have not been extensively studied. Recently, we found that berry volatiles from cranberries, black and red raspberries, strawberries, blueberries, and blackberries have an anti-inflammatory effect on inflamed murine macrophage cells. Since inflammation can develop into many chronic diseases, and berry volatiles can be inhaled or consumed and pass through the lungs or …

Amyloid Fibrils Of Human Fgf-1 Induced By Different Detergents, Zeina Ismael Ibrahem Alraawi

Graduate Theses and Dissertations

Nature achieves molecular self-assembly through the ordered growth of nanoscale building blocks with high efficiency to fabricate macromolecular architectures. One example of self- assembly is peptides folding onto protein is one of the most astounding biological self-assembly processes. When proteins aggregate to form amyloid fibers, the secondary structure of the protein converts from its native state to a cross-beta-sheet. Fibroblast growth factors (FGFs) possess an essential role in neuronal survival during development. In addition, they are involved in neural stem cell (NSC) proliferation. Fibroblast growth factors (FGFs) are well known to be synthesized in the central nervous system (CNS) and …

Characterization Of Human Fibroblast Growth Factor 2 Variant To Determine Effects On Structure, Stability, And Cell Proliferation, Ryan Layes

Graduate Theses and Dissertations

Fibroblast growth factors (FGFs) are a family of cell signaling proteins conserved across multiple species. Each individual FGF elicits different cellular functions including, but not limited to, proliferation, migration, differentiation, angiogenesis, and wound healing. One of the most studied members, fibroblast growth factor 2 (FGF2), has demonstrated substantial wound healing capacity in a wide range of tissues including skeletal, muscular, neural, respiratory, epithelial, and cardiovascular. This ability makes FGF2 a potential therapeutic for a wide range of conditions and injuries. However, due to a short half-life at room temperature, therapeutic use of FGF2 is limited. It has been demonstrated that …

Habitat Associations Of Plains Spotted Skunk (Spilogale Interrupta) Across The Plains Ecoregion. And The Landcover Occupancy Models Of The Gray Fox (Urocyon Cinereoargenteus) In The Southeastern Plains Region In Arkansas, Michael Shaw

Graduate Theses and Dissertations

Much of the landscape of the United States has been altered by humans, leading to the eradication of most populations of large mammalian predators. Consequently, many species of mammalian mesopredators (medium-sized mammalian predators) have come to dominate the landscape. Species such as the gray fox (Urocyon cinereoargenteus) may appear to be on the rise and doing well due to their widespread range, but at a local scale may need monitoring and less is known in areas of its range. Others such as the plains spotted skunk have a wide range across the plains but are on the decline even with …

From Periphery To Center: Re-Presenting Black And Afro-Arab Characters In Contemporary Arabic Literature, Samer Ahmad Mayyas

Graduate Theses and Dissertations

Black Arabs and Afro-Arabs tend not to be centered in Arabic discourse, especially modern Arabic literature, and Black people of other ethnicities are marginalized, as if Black peoples and Afro-Arabs were not part of the history and present-day of the Arabic-speaking world. I explore in this dissertation project the representations and experiences of Black and Afro-Arabs in contemporary Arabic fictional narratives. I argue that the contemporary literary era sees a shift in re-presenting Black peoples and Afro-Arabs in the Arabic fictional discourse. By moving Black and Afro-Arab characters from periphery to center, contemporary Arab writers challenge and disrupt, in an …

Human-Bat Interactions In A Disease Emergence Hotspot: Implications For Human Health And Bat Conservation, Reilly Tempest Jackson

Graduate Theses and Dissertations

Bats are an ecologically important taxon that can host zoonotic pathogens. Globally, many bat species are synanthropic and live closely with humans, often roosting in man-made structures. The spatial overlap between humans and bats creates opportunities for human-bat contact, which can lead to human exposure to bat-borne pathogens and conflicts that cause bat mortality. Despite this risk, little is known about the drivers and characteristics of these human-bat interactions in buildings and work is needed to understand this aspect of the wildlife-urban interface. In Chapter I, I present a literature review that identifies the geographic and taxonomic trends in reported …

The Effects Of Diet, Size, And Phylogeny On Primate Dental Proportions, Rudolph J. Wilkins

Graduate Theses and Dissertations

It is generally appreciated that there is a relationship between the relative size of the incisors, mandible length, and diet in primates. More specifically, the differences in relative incisor size among primate species are believed to be evolutionary adaptations to their use during food processing and acquisition. While this satisfactorily explains relatively large incisors, it fails to address the relatively small incisor size seen in many taxa. One hypothesis is that there is a trade-off between molar size and incisor size in species with relatively short mandibles. The following study uses two-way ANOVA to evaluate the possibility that spatial constraint …

Assessment Of Needs And Priorities For Precision Agriculture And Soil Testing In Arkansas, Solomon Frimpong

Graduate Theses and Dissertations

Optimum crop production is needed to meet the growing population's food, water, fiber, and energy needs. However, agricultural productivity is hampered by many destabilizing factors such as pest management challenges, declining water quantity, and climate change which threaten long-term food security. Maximizing productivity will require optimizing resources through Precision Agriculture (PA) by supplying inputs based on crop needs. Precision Agriculture offers tools that can be used to optimize crop management practices globally. However, stakeholders’ perceptions and the lack of data-driven site-specific recommendations limit stakeholders’ ability to fully harness the potential benefits of PA. Identification of stakeholder needs and approaches to …

Demographics, Sexual Dimorphism, And Ecological Aspects Of Ambystoma Annulatum (Ringed Salamander) In Northwest Arkansas, Usa, Brian M. Becker

Graduate Theses and Dissertations

The need to study and monitor amphibian populations is increasing along with the threats to their population stability and persistence in nature. Northwest Arkansas is one of the fastest growing areas in the nation and with that growth comes rapid changes in land use, massive alterations to habitats, habitat loss, and the introduction of nonnative plants and animals. Ambystoma annulatum (Ringed Salamander) is an Ambystomatid endemic to the Ozark and Ouachita Mountains of southern Missouri, northern and western Arkansas, and eastern Oklahoma giving it a relatively small distribution compared to most Ambystoma. Therefore, Arkansas constitutes a significant portion of the …

Characteristics Of Award-Winning Children’S Books About Agriculture: An Analysis Of Content, And The Perspectives Of Authors, Illustrators, And Publishers, Addison L. Beckham

Graduate Theses and Dissertations

The purpose of this two-article qualitative study was to characterize children's literature about agriculture and to describe the perceptions of authors and illustrators who are responsible for writing and designing these successful publications. This will result in the ability of organizations like Feeding Minds Press to provide writers, illustrators, and publishers with effective strategies and techniques to improve the accuracy and overall quality of children’s literature about agriculture. Few parameters exist for authors of children’s books about agriculture (Biser, 2007). These parameters are necessary to ensure the quality and accuracy of these educational efforts (Serafini, 2012). Though Feeding Minds Press …

Evaluation Of Oxyfluorfen For Use In Roxy Rice, Casey Hunter Arnold

Graduate Theses and Dissertations

Mid-southern U.S. rice (Oryza sativa L.) producers are challenged every year to control problematic barnyardgrass [Echinochloa crus-galli (L.) Beauv.] and weedy rice (Oryza sativa L.) because they have evolved resistance to most labeled herbicides. Oxyfluorfen is a Herbicide Resistance Action Committee (HRAC)/Weed Science Society of America (WSSA) Group 14 herbicide that inhibits protoporphyrinogen oxidase within the plant. Currently, there are no HRAC/WSSA Group 14 herbicides labeled for barnyardgrass or weedy rice control in midsouthern rice production. Therefore, oxyfluorfen is being evaluated for barnyardgrass and weedy rice control. Plant breeders at the University of California – Davis were able to breed …

Overexpression Of Acetyl Coa Carboxylase 1 And 3 (Accase1 And Accase3), And Cyp81a21 Were Related To Cyhalofop Resistance In A Barnyardgrass Accession From Arkansas, Fidel Gonzalez-Torralva, Jason K. Norsworthy

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Barnyardgrass [Echinochloa crus-galli (L.) P. Beauv.] is the most difficult-to-control weed species of rice production systems worldwide. It has evolved resistance to different herbicide sites of action, including the acetyl-CoA carboxylase (ACCase)-inhibiting herbicides. Target-site mutations conferring resistance to ACCase-inhibiting herbicides are well documented; however, the role of the different ACCase genes in conferring resistance to cyhalofop-p-butyl (cyhalofop), an ACCase-inhibiting herbicide, remains poorly understood. This research assessed the contribution of gene amplification and expression of ACCase genes in a cyhalofop-resistant barnyardgrass accession. Additionally, the expression of glutathione-S-transferases (GSTs) and cytochrome P450 monooxygenases (P450s) genes as possible …

Comparative Analysis Of Teacher Effects Parameters In Models Used For Assessing School Effectiveness: Value-Added Models & Persistence, Merlin J. Kamgue

Graduate Theses and Dissertations

Longitudinal measures for students have become increasingly popular to estimate the effects of individual teachers and schools. Value-added models are one of the approaches using longitudinal data to evaluate teachers and schools. In the value-added model (VAM) literature, many statistical approaches have been developed and used to estimate teacher or school effects on student learning. This study opted to use a Bayesian multivariate model for evaluating teacher effects. The generalized persistence models can handle longitudinal data, not vertically scaled, allowing for a below-par teacher’s effects correlation across test administrations. This study first generated longitudinal students’ test score data and used …

Effects Of Landcover On Mesocarnivore Density And Detection Rate Along An Urban To Rural Gradient, Leah E. Mctigue, Brett Degregorio

Biological Sciences Faculty Publications and Presentations

Human development has major implications for wildlife populations. Urban-exploiter species can benefit from human subsidized resources, whereas urban-avoider species can vanish from wildlife communities in highly developed areas. Therefore, understanding how the density of different species varies in response to landcover changes associated with human development can provide important insight into how wildlife communities are likely to change and provide a starting point for predicting the consequences of those changes. Here, we estimated the population density of five common mesocarnivore species (coyote (Canis latrans), bobcat (Lynx rufus), red fox (Vulpes vulpes), raccoon (Procyon …

Interactions Between Fitness Components Across The Life Cycle Constrain Competitor Coexistence, Miguel Gómez-Llano, Wade A. Boys, Taylor Ping, Simon P. Tye, Adam M. Siepielski

Biological Sciences Faculty Publications and Presentations

1. Numerous mechanisms can promote competitor coexistence. Yet, these mechanisms are often considered in isolation from one another. Consequently, whether multiple mechanisms shaping coexistence combine to promote or constrain species coexistence remains an open question.
2. Here, we aim to understand how multiple mechanisms interact within and between life stages to determine frequency-dependent population growth, which has a key role stabilizing local competitor coexistence.
3. We conducted field experiments in three lakes manipulating relative frequencies of two Enallagma damselfly species to evaluate demographic contributions of three mechanisms affecting different fitness components across the life cycle: the effect of resource competition on individual growth …

Exploring The Potential Of Tesla Valve For Filtering And Sorting Microscale Active Swimmers: A Computational Study, Ariel Rogers, Zhiyao He, Yong Wang

Physics Faculty Publications and Presentations

It is well-known that a Tesla valve allows fluids to flow unidirectionally without moving parts; however, how Tesla valves interact with active matters and the potential applications of Tesla valves in biology remain largely unexplored. Here, we present a computational study on the potential use of Tesla valves for filtering and sorting microscale active swimmers such as bacteria. We investigated the behavior of microscale swimmers passing through the Tesla valve at different linear and angular velocities using numerical simulations and quantified the diodicity of the Tesla valve for active swimmers. Our results demonstrate that the Tesla valve can effectively filter …

Sensory Input To Cortex Encoded On Low-Dimensional Periphery-Correlated Subspaces, Andrea K. Barreiro, Antonio J. Fontenele, Cheng Ly, Prashant Chama Raju, Shree Hari Gautam, Woodrow L. Shew

Physics Faculty Publications and Presentations

As information about the world is conveyed from the sensory periphery to central neural circuits, it mixes with complex ongoing cortical activity. How do neural populations keep track of sensory signals, separating them from noisy ongoing activity? Here, we show that sensory signals are encoded more reliably in certain low-dimensional subspaces. These coding subspaces are defined by correlations between neural activity in the primary sensory cortex and upstream sensory brain regions; the most correlated dimensions were best for decoding. We analytically show that these correlation-based coding subspaces improve, reaching optimal limits (without an ideal observer), as noise correlations between cortex …

Developing Recommendations For Broad Mite, Polyphagotarsonemus Latus Banks, In Blackberry, Rubus Subgenus Rubus, Jared Bradley Linn

Graduate Theses and Dissertations

Broad mite, (Polyphagotarsonemus latus Banks) (Acari: Tarsonemidae), is an economically important pest of blackberry production across the world. Since it was first reported on primocane-fruiting blackberries in 2010, little work has gone into developing IPM tools and understanding impact on floricane-fruiting cultivars. The objective of this thesis was to evaluate the effect of broad mite feeding on floricane-fruiting cultivars of blackberry, develop an efficient and accurate field scouting strategy, and investigate the impact of cultivar and trellising technique on the development of broad mite populations. Experiments consisted of evaluating floricane fruiting cultivars by quantifying broad mite populations and cataloging their …