Digital Commons Network^™

3d Printing Of Iron Oxide Incorporated Polydimethylsiloxane Soft Magnetic Actuator, Rasoul Bayaniahangar

Dissertations, Master's Theses and Master's Reports

Soft actuators have grown to be a topic of great scientific interest recently. As the fabrication of soft actuators with conventional microfabrication methods are tedious, expensive, and time consuming, employment of 3-D printing fabrication methods appears promising as they can simplify fabrication and reduce the production cost. Complex structures can be fabricated with 3-D printing such as helical coils can achieve actuation performances that otherwise would not be possible with simpler geometries. In this thesis development of soft magnetic helical coil actuators of iron-oxide embedded polydimethylsiloxane (PDMS) was achieved with embedded 3-D printing techniques. Composites with three different weight ratios …

Detection And Thermal Stabilization Of Virus Based On Surface Properties, Xue Mi

Dissertations, Master's Theses and Master's Reports

Viral diseases take the lives of millions of people each year. The most effective methods to prevent viral disease outbreak are viral detection to reduce contact with viral pathogens and vaccines to prevent disease. To reduce the costs of the detection of viruses and improve vaccine formulation, we explored viral surface properties. The properties we have focused on are viral hydrophobicity and surface charge using chemical force microscopy (CFM). CFM is a single-particle technique that measures the adhesion force of a functionalized atomic force microscopy (AFM) probe, and in this study, a virus covalently bound to a surface. The non-enveloped …

Ratiometric Near-Infrared Fluorescent Probes For The Sensitive Detection Of Intracellular Ph And Bio-Thiols In Live Cells, Shuai Xia

Dissertations, Master's Theses and Master's Reports

In the past twenty years, fluorescence sensing and imaging based on fluorescent probes has been developed as an imperative technique due to the merits including excellent sensitivity, operational simplicity, instant time effectiveness and outstanding selectivity in the research areas such as mineralogy, gemology, biological medicine, materials and environmental engineering. Protons act as a significant role in a variety of pathological and physiological processes, and there are obvious differences in the pH among organelles: the pH in lysosomes is acid within the range of 4.5–5.5, whereas mitochondrial pH is basic that can be as high as 8.0. Abnormal intracellular pH is …

Biocide Resistance As A Result Of Exposure To Biocides Used In Hydraulic Fracturing, Lindsey Schenten

Dissertations, Master's Theses and Master's Reports

Microbial resistance to antimicrobials is an important topic to investigate not only for our health but for the environment. There is a growing concern about expanding microbial resistance to both antibiotics and other antimicrobials such as biocides. We wanted to know how bacteria previously exposed to hydraulic fracturing fluids, including biocides, would react to biocide exposure and what the mechanism of resistance looked like. In order to test this hypothesis bacterial isolates were obtained from water and sediment from a stream that had been previously exposed to a spill of hydraulic fracturing water. Thirty bacterial isolates were obtained from these …

Aging Pipeline Infrastructure In The United States: How Do A Changing Policy Mix, Issues Of Energy Justice, And Social Media Communication Impact Future Risk Analysis?, Brent Burns

Dissertations, Master's Theses and Master's Reports

Over two and a half million miles of pipeline cross the United States today, half of which is over fifty years old and thus was designed, located, and debated without today’s modern environmental policies in place. Aging pipeline infrastructure, such as the (infamous in Michigan) Enbridge Line 5 pipeline underwater crossing at Michigan’s Straits of Mackinac, has undergone increased public scrutiny and risk analysis this past decade. This has led to the potential for policy changes in the historically stable energy services institution associated with pipeline infrastructure regulation. While policy process literature generally describes how policy changes over time, it …

The Effect Of Hibiscus.Sabdariffa. L On Blood Pressure And Arterial Stiffness In Humans, Basirat Tolulope Shittu

Dissertations, Master's Theses and Master's Reports

Cardiovascular diseases (CVD) are the foremost cause of death worldwide. The main risk factor for CVD is uncontrolled hypertension (HTN). The prescription of only anti-hypertensive regimens in the management of HTN is becoming more challenging due to the high cost and adverse effects linked to the persistent usage of the drugs. Eighteen participants completed the study by consuming 2g of Hibiscus sabdariffa or oolong tea twice daily for six weeks. We lost an additional twelve participants in the study due to the COVID-19 pandemic. Central arterial stiffness was analyzed as cfPWV using applanation tonometry technique. The HS tea intervention (n=11) …

Modeling The Effects Of Hydrologic Service Payments On The Hydrology Of Tropical Montane Watersheds In Central Veracruz, Mexico., Sergio Miguel López Ramírez

Dissertations, Master's Theses and Master's Reports

An analysis of the effects of the Land Use Land Cover (LULC) change and its impacts on the hydrological cycle of tropical montane catchments influenced by cloud forest (TMCF) is developed in Central Veracruz, Mexico. This work started with the analysis of data from monitored-micro-catchments with contrasting LULC. Later the suitability of an improved version of the Soil and Water Assessment Tool model for the Tropics (SWAT-T) was evaluated. Finally, potential future land use scenarios, including conservation targeting alternatives were evaluated using a calibrated Seasonal Water Yield model as part of the Integrated Valuation of Ecosystem Services and Tradeoffs framework …

Inequality In The Social Mind: Social Comparison And Support For Redistribution, Meghan Condon, Amber Wichowsky

Political Science Faculty Research and Publications

Income inequality is fundamentally relational in nature, but research on the American public’s response to it tends to examine individuals in isolation, concluding that support for redistribution is unresponsive to inequality. We focus instead on perceptions of relative socioeconomic position, which we manipulate experimentally through imagined social interactions with high- or low-status others. We find that subjects who make social comparisons between themselves and someone who is socioeconomically advantaged perceive their own status as lower, assess their own socioeconomic status more accurately, and become more supportive of social welfare spending, even though we provide no factual information about the income …

The Policy State And The Post-Truth Presidency, Philip Rocco

Political Science Faculty Research and Publications

No abstract provided.

Preconditioning Of Mesenchymal Stromal Cells With Low-Intensity Ultrasound: Influence On Chondrogenesis And Directed Sox9 Signaling Pathways, Neety Sahu, Gaurav Budhiraja, Anuradha Subramanian

Department of Chemical and Biomolecular Engineering: Faculty Publications

Background: Continuous low-intensity ultrasound (cLIUS) facilitates the chondrogenic differentiation of human mesenchymal stromal cells (MSCs) in the absence of exogenously added transforming growth factor-beta (TGFβ) by upregulating the expression of transcription factor SOX9, a master regulator of chondrogenesis. The present study evaluated the molecular events associated with the signaling pathways impacting SOX9 gene and protein expression under cLIUS.

Methods: Human bone marrow-derived MSCs were exposed to cLIUS stimulation at 14 kPa (5 MHz, 2.5 Vpp) for 5 min. The gene and protein expression of SOX9 was evaluated. The specificity of SOX9 upregulation under cLIUS was determined by treating the MSCs …

Identifying Meaningful Individual-Level Change In Educational Experiences: Adding To Our Methodological Toolkit, Elizabeth Niehaus, Gudrun Nyunt

Department of Educational Administration: Faculty Publications

In recent years, improving the quantitative methods used to assess the effect of college, and particular college experiences, on student outcomes has received increased attention (e.g., Mayhew et al., 2016). In How College Affects Students, Mayhew et al. (2016) highlighted the importance of issues of practical vs. statistical significance, self-selection into college (and by extension, self-selection into particular experiences), and direct and indirect effects, among other methodological challenges in identifying the relationships between college experiences and student learning and success. One particularly difficult challenge is identifying the conditional effects of experiences on student outcomes. Who benefits, or who does not, …

Exploring Cultural Logic In Becoming Teacher: A Collaborative Autoethnography On Transnational Teaching And Learning, Taeyeon Kim, Heather L. Reichmuth

Department of Educational Administration: Faculty Publications

Departing from the view that learning is a linear progression, we argue that through the lens of cultural historical activity theory (CHAT) and cultural logic, teacher learning research can be advanced. Applying these two constructs to a collaborative autoethnography of two emerging scholars’ transnational teaching and learning experiences in the US and South Korea we argue that implicit and explicit norms in a culture influence the process of becoming teacher in the Korean context. Findings suggest that socio-cultural elements of implicit beliefs and norms outside of schools are linked to teacher learning inside schools, thereby suggesting that teacher learning at …

Computation-Driven Analysis Of Model Polyextremo- Tolerant Fungus Exophiala Dermatitidis: Defensive Pigment Metabolic Costs And Human Applications, Wheaton L. Schroeder, Steven D. Harris, Rajib Saha

Department of Chemical and Biomolecular Engineering: Faculty Publications

Extremophiles are organisms that can live in extreme conditions of temperature, acidity, alkalinity, or salinity. Studying these organisms not only expands our knowledge on the diversity of life but can also provide significant insights into how organisms adapt to stress, particularly metabolic and regulatory responses. Exophiala dermatitidis (hereafter, Exophiala or E. dermatitidis, also known as Wangiella derma- titidis), a highly melanized black fungus and perhaps best known for its H. sapiens (hereafter, human) path- ogenic properties (Paolo et al., 2006; Poyntner et al., 2016; Sudhadham et al., 2008), is a potential model extremophile system owing to its small genome of …

Reframing Community (Dis)Engagement: The Discursive Connection Between Undemocratic Policy Enactment, Minoritized Communities And Resistance, James S. Wright, Taeyeon Kim

Department of Educational Administration: Faculty Publications

While studies have examined leadership efforts to improve community engagement, less is known about how deeply rooted structured discourses, systems, and practices influence leadership actions and responses from communities. Deficit approaches to educational policy reform are pervasive in the most historically marginalized communities and school districts in the United States (US). Drawing on critical policy analysis, this study examines a disengaged school district’s leadership of a Federal School Turnaround Policy from the perspectives of minoritized communities in an urban US school district. We analyzed deficit policy discourses, its enactment, and leadership practices using interview data and archived documents. This study …

Engineered Clostridium Botulinum Toxin Adapted To Deliver Molecules Into Selected Cells, Benjamin J. Pavlik, Paul Blum, Kevin Van Cott

Department of Chemical and Biomolecular Engineering: Faculty Publications

An engineered payload-delivery system includes a target cell binding unit, covlently bound to a pore forming unit, and a payload portion adapted with a region capable of non-covalently binding to the pore forming unit. The pore forming unit is derived from a particular sub-serotype of Clostridium toxin, while the payload region is derived from a different sub-serotype of Clostridium toxin. The disclosed chimeri protein-based composition is capable of specifically delivering payload to neural cells.

Leveraging Plasma-Derived Exosomes For Biomarker Discovery In Sickle Cell Disease: Preparation For A Large Prospective Study, Y. Lamarre, A. Aich, Mohammad Mazharul Islam, J.M. Scianni, A.C.S. Pinto, A.M.C Tavassie, J. Elion, W.E. Nemer, Rajib Saha, S. Kashimab, D.T. Covas

Department of Chemical and Biomolecular Engineering: Faculty Publications

Diverse clinical variability among sickle cell disease (SCD) patients opposes crises prediction, health monitor- ing and streamlined management. Thus, an unmet need for objective biomarkers prevails. Exosomes are extra-cellular nano-vesicles (50-150nm), enriched in bioactive lipids, proteins, mRNAs and miRNAs, released by cells. They transport molecular cargo to nearby/distant cells to affect-regulate biological processes. Recent studies by Khalyfa et al. assessed the plasma exosome content, their sources and transcriptomics signature as predictive marker in SCD children with acute chest syndrome. However, the small sample sizes (32 and 33 individuals, respectively) may not capture the clinical variability.

Investigation Of Microbial Community Interactions Between Lake Washington Methanotrophs Using Genome-Scale Metabolic Modeling, Mohammad Mazharul Islam, Tony Le

Department of Chemical and Biomolecular Engineering: Faculty Publications

Background. The role of methane in global warming has become paramount to the environment and the human society, especially in the past few decades. Methane cycling microbial communities play an important role in the global methane cycle, which is why the characterization of these communities is critical to understand and manipulate their behavior. Methanotrophs are a major player in these communities and are able to oxidize methane as their primary carbon source.

Results. Lake Washington is a freshwater lake characterized by a methane-oxygen countergradient that contains a methane cycling microbial community. Methanotrophs are a major part of this community involved …

Novel Fibrin-Fibronectin Matrix Accelerates Mice Skin Wound Healing, Carlos Poblete Jara, Ou Wang, Thais Paulino Do Prado, Ayman Ismailc, Frank Marco Fabianc, Han Li, Licio A. Velloso, Mark A. Carlson, William Burgess, Yuguo Lei, William H. Velander, Eliana P, Araújo

Department of Chemical and Biomolecular Engineering: Faculty Publications

Plasma fibrinogen (F1) and fibronectin (pFN) polymerize to form a fibrin clot that is both a hemostatic and provisional matrix for wound healing. About 90% of plasma F1 has a homodimeric pair of γ chains (γγF1), and 10% has a heterodimeric pair of γ and more acidic γ′ chains (γγ′F1). We have synthesized a novel fibrin matrix exclusively from a 1:1 (molar ratio) complex of γγ′F1 and pFN in the presence of highly active thrombin and recombinant Factor XIII (rFXIIIa). In this matrix, the fibrin nanofibers were decorated with pFN nanoclusters (termed γγ′F1:pFN fibrin). In contrast, fibrin made from 1:1 …

Functional Genetic Encoding Of Sulfotyrosine In Mammalian Cells, Xinyuan He, Yan Chen, Daisy Guiza Beltran, Maia Kelly, Bin Ma, Justin Lawrie, Feng Wang, Eric Dodds, Limei Zhang, Jiantao Guo, Wei Niu

Department of Chemical and Biomolecular Engineering: Faculty Publications

Protein tyrosine O-sulfation (PTS) plays a crucial role in extracellular biomolecular interac- tions that dictate various cellular processes. It also involves in the development of many human diseases. Regardless of recent progress, our current understanding of PTS is still in its infancy. To promote and facilitate relevant studies, a generally applicable method is needed to enable efficient expression of sulfoproteins with defined sulfation sites in live mammalian cells. Here we report the engineering, in vitro biochemical characterization, structural study, and in vivo functional verification of a tyrosyl-tRNA synthetase mutant for the genetic encoding of sulfotyrosine in mammalian cells. We further …

Ionomers From Kraft Lignin For Renewable Energy Applications, Seefat Farzin, Tyler J. Johnson, Shyambo Chatterjee, Ehsan Zamani, Shudipto Konika Dishari

Department of Chemical and Biomolecular Engineering: Faculty Publications

Converting industrial/agricultural lignin-rich wastes to efficient, cost-effective materials for electrochemical devices (e.g., fuel cells) can aid in both bio- and energy economy. A major limitation of fuel cells is the weak ion conductivity within the ∼2–30-nm thick, ion-conducting polymer (ionomer)-based catalyst-binder layer over electrodes. Here, we strategically sulfonated kraft lignin (a by-product of pulp and paper industries) to design ionomers with varied ion exchange capacities (IECs) (LS x; x = IEC) that can potentially overcome this interfacial ion conduction limitation. We measured the ion conductivity, water uptake, ionic domain characteristics, density, and predicted the water mobility/stiffness of Nafion, LS 1.6, …

Personalized Learning: An Engagement Strategy For At-Risk Student Populations, Abbigail Morris

Murray State Theses and Dissertations

Personalized learning in the United States experienced a resurgence in the educational landscape as a result of increased technology access and computing power. The availability of affordable technology, software solutions, and access to the Internet led to the infiltration of technology into personalized learning approaches and provided a new platform for personalized learning advocates. Engagement and student agency were components of personalized learning attracting many educators to reinvest in personalized learning opportunities. This study focused on a rural, western Kentucky school district that piloted personalized learning through a blended learning environment. The study sought to measure engagement levels of both …

Paleofloods And Landform Development Influence Carbon Storage In A Humid-Subtropical River Valley, Christopher Lance Stewart

Murray State Theses and Dissertations

Floodplains can store large amounts of soil organic carbon (SOC) despite covering a small fraction of the global land area. Since these valley-bottom landforms build through the action of flooding, the century to millennial-scale record of overbank deposition could be important in understanding controls on deep (>30 cm) SOC storage. Yet, the influence of flood history and landform development on carbon content is surprisingly not well known. I use a combined geological and pedological approach to characterize the sedimentation, soil development, and SOC of fluvial terraces along an impounded reach of the humid-subtropical Tennessee River valley, U.S.A. The standardized …

Population Demographics Of Silver Carp Hypophthalmichthys Molitrix In Kentucky Lake, Allison M. Lebeda

Murray State Theses and Dissertations

Invasive species continue to threaten aquatic ecosystems in the United States. Silver Carp Hypophthalmichthys molitrix have successfully infiltrated much of the Mississippi River Basin, including Kentucky Lake – a large reservoir located on the Tennessee River in Western Kentucky. Although Silver Carp have been present in Kentucky Lake for at least a decade, until recently, very little was known about the population, how often successful reproduction is occurring, or the environmental conditions that facilitate strong year-classes. Hence, it is difficult for managers to predict the potential impact of Silver Carp on native species. Silver Carp were collected from Kentucky Lake …

Analyzing Citation Metrics In Civil Engineering With Focus On Construction Engineering And Management, Islam H. El-Adaway, Gasser G. Ali, Rayan Assaad, Amr Elsayegh, Ibrahim S. Abotaleb

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

There are several metrics used to evaluate academic publications, including number of citations, h-index, and others. While these metrics are directly related to rewards in the academic community, it is debated whether they correctly reflect the true impact of research. As such, there is a need to clearly interpret and understand such metrics. The goal of this paper is to investigate the citation metrics used to assess academic publications in civil engineering (CE) with a considerable focus on construction engineering and management (CEM). The investigation of these two research fields is important since each one of them has its own …

Simulating Der Adoption In Wholesale Power Markets Using Agent Based Computational Economics, Islam H. El-Adaway, Charles Sims, Mohamed Eid, Yinan Liu, Gasser Galal Ali

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

There is a transition from centralized electricity generation to distributed energy resources (DER). An increasing number of customers are adopting distributed solar generation (DSG). However, utilities face the difficulty of predicting electrical demand and therefore dispatching and controlling generation. The goal of this research is to study the evolving dynamic market behavior affected by DER investment decisions. To that end, agent-based modeling (ABM) is used to study the emerging behavior of the market under those conditions. The model is developed from the existing and validated AMES framework, which is used for agent-based computational economics (ACE) simulation of wholesale power markets. …

Influence Of Pumping Pressure On The Viscosity Curve And Rheological Stability Of Mortar Incorporating Polycarboxylate, Jae Hong Kim, Seong Ho Han, Byoung Il Choi

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Concrete pumping has been successfully adopted in modern construction. Various concrete including high-strength concrete and self-consolidating concrete can be pumped, but we still have a lack of understanding of the rheological behavior and its change during the pumping process. This study evaluates the effect of pumping pressure on the viscosity curves of cement-based materials incorporating a specific polycarboxylate. The viscosity of mortar samples increases with the pumping pressure. The viscosity increase depends on the rate of shear strain and the polymer structure of the polycarboxylate. The effect of pumping pressure is then generalized with a Sisko model. A mechanistic model …

A Justification For Continued Management Of Turfgrass During Economic Contraction, James T. Brosnan, Ambika Chandra, Roch E. Gaussoin, Alec Kowalewski, Bernd Leinauer, Frank S. Rossi, Douglas J. Soldat, John C. Stier, J. Bryan Unruh

Department of Agronomy and Horticulture: Faculty Publications

A novel coronavirus, termed COVID-19, spread worldwide and become a global pandemic in 2020. Forecasts show that COVID-19 will cause substantial economic contraction affecting almost every industry. Managed turfgrass, particularly in urban settings, has many positive societal and environmental benefits. In a contracted economy, will resources be available to manage turfgrass to achieve these benefits? In this paper, we outline the benefits of managed turfgrass on golf courses, playing fields, recreational parks, and urban landscapes to assist decision makers with resource allocation in the COVID-19 era.

Strategic Switchgrass (Panicum Virgatum) Production Within Row Cropping Systems: Regional-Scale Assessment Of Soil Erosion Loss And Water Runoff Impacts, Enheng Wang, R. M. Cruse, Bharat Sharma-Acharya, Daryl E. Herzmann, Brian K. Gelder, David E. James, Dennis C. Flanagan, Humberto Blanco-Canqui, Robert B. Mitchell, David Laird

Department of Agronomy and Horticulture: Faculty Publications

A strong need exists for tools to assess the efficacy of conservation practices across large regions supporting informed policy decisions that may lead to better soil and water conservation while optimizing agricultural production options. Perennial warm-season grasses (WSGs) such as switchgrass (Panicum virgatum), can be grown on marginally productive and/or environmentally sensitive lands to meet growing bioenergy demands while reducing water runoff and soil erosion compared to current row crop systems. Quantifying the soil and water conservation effects of WSG when strategically placed on the landscape would help support decisions favoring both economic and environmental benefits. We used the Daily …

Benchmarking The Agronomic Performance Of Biodegradable Mulches Against Polyethylene Mulch Film: A Meta‐Analysis, Mauro B.D. Tofanelli, Samuel E. Wortman

Department of Agronomy and Horticulture: Faculty Publications

Growers are interested in biodegradable alternatives to petroleum‐based polyethylene mulch film (PEM). However, many growers cite limited knowledge about biodegradable mulch films (BDMs) as a significant barrier to adoption. Agronomic field tests of BDMs are often limited temporally or spatially, and the variability of performance results relative to PEM may be contributing to this perceived knowledge gap. Our objective was to use data available in the scientific literature to provide the first quantitative performance benchmark of BDMs against PEM. We extracted data from 66 articles for meta‐analysis. Response ratios were calculated for comparison of BDMs relative to black PEM, and …

Evaluation Of The Specific Attenuation Method For Radar-Based Quantitative Precipitation Estimation: Improvements And Practical Challenges, Bong Chul Seo, Witold F. Krajewski, Alexander Ryzhkov

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study demonstrates an implementation of the prototype quantitative precipitation R estimation algorithm using specific attenuation A for S-band polarimetric radar. The performance of R(A) algorithm is assessed, compared to the conventional algorithm using radar reflectivity Z, at multiple temporal scales. Because the factor a, defined as the net ratio of A to specific differential phase, is a key parameter of the algorithm characterized by drop size distributions (e.g., differential reflectivity Zdr dependence on Z), the estimation equations of a and a proper number of Zdr–Z samples required for a reliable a estimation are examined. Based on the dynamic estimation …