Skip to Main Content

Basic Search

Skip to Search Results
 
 
 

Left Column

Filters

Show More

Show More

Show More

Right Column

Search Results

Search Results

(Total results 117)

Mini-Tools

 
 

Search Report

  • 1. Zhuo, Junqi NOVEL METHODS OF THERMALLY MEDIATED SELECTIVE NEURAL INHIBITION

    Doctor of Philosophy, Case Western Reserve University, 2023, Biomedical Engineering

    Small-diameter axons (e.g., unmyelinated C fibers) are commonly afferent axons that carry critical sensory signals. Selective inhibition of dysfunctional small-diameter axons can be useful for basic neuroscience research and lead to treatments for neurological diseases (e.g., neuropathic pain and persistent hypertension), but remains an unmet need. Conventional pharmaceutical targets are distributed throughout the body, which causes systematic side effects. Electrode-based neuromodulation modalities tend to block large-diameter axons first. Other efforts, such as multi-electrode designs, have achieved spatial selectivity, which is challenged by the degradation of electrode performance due to immune responses. There is a need for a modality that can intrinsically and reliably induce size-selective inhibition of small-diameter axons. Our lab and collaborators have demonstrated in previous studies that infrared (IR) neural inhibition (INI) can selectively inhibit small-diameter axons via the heat induced by the absorption of IR light (e.g., 1470 nm, 1860 nm) which thermally accelerates ion9 channel dynamics. In this work, we first explored the possibility of lowering the IR power threshold for INI with isotonic ion replacement using glucose and/or choline in the extracellular fluid. We applied IR and isotonic ion replacement simultaneously to the same nerve segment, both at a sub-threshold level, and the results confirmed that the IR power threshold of size-selective INI can be lowered by isotonic ion replacement. Second, we tested the hypothesis that resistive heating can reproduce the size selectivity of INI. We fabricated a customized resistive heating cuff and tested localized heat application via both resistive heating and INI on the same nerve. The experimental results confirmed that resistive heating can reproduce the size-selective inhibition on small-diameter axons with higher overall energy efficiency. Further numerical simulation showed (open full item for complete abstract)
    ... More

    Committee: Andrew Rollins (Committee Chair); Michael Jenkins (Committee Member); Kenneth Laurita (Committee Member); Dustin Tyler (Committee Member); Hillel Chiel (Committee Member) Subjects: Biomedical Engineering

  • 2. Westdorp, Clayton The Influence of Focal Knee Joint Cooling on Thigh Neuromechanical Function

    Master of Science, University of Toledo, 2019, Exercise Science

    Many individuals experience persistent quadriceps muscle weakness due to underlying inhibition following injury. Focal knee joint cooling (FKJC) is one disinhibitory intervention that can increase quadriceps muscle performance. However, FKJC has not been assessed for its impact on the hamstrings or other neuromechanical properties of muscle contractions. Therefore, the purpose of this study was to analyze the impact of FKJC on thigh muscle neuromechanical function. Physically active volunteers with a self-reported history of knee joint injury and documented quadriceps activation failure were recruited to participate. Six individuals were included in the study. ((4 female and 2 male, mean age 22.67 ± 2.42 (range; 20-27), height 172.61 ± 11.92 cm, mass 74.46 ± 17.50 kg.)) Central activation ratio (CAR), electromechanical delay (EMD), rate of torque development (RTD), and torque variability (CV) were recorded at four time points, two pre-intervention and two post intervention. A 20-minute FKJC treatment served as the intervention. One-way analysis of variance with repeated measures was used for comparisons. Effect sizes were calculated to describe the magnitude of the differences. There were no significant differences between main outcome measures across the four collection time points. Large effect sizes were determined between the baseline 2 and post intervention 2 timepoints for EMD of the quads (ES 2.75; CI 0.70, 4.44), pain (ES 0.80; -0.64, CI 2.24), and fatigue (ES 0.85; CI -0.60, 2.30). Moderate effect sizes were determined for EMD of the quads (ES 0.79; CI -0.65, 2.23), torque variability of the hamstrings (ES 0.56; CI -0.85, 1.97), and fatigue (ES 0.55; CI -0.86, 1.96) between the baseline 2 and post intervention 1 time points. Effect sizes indicate a greater response from the quadriceps following FKJC compared to the hamstrings. However, the only certain response from either muscle group is an increase in quadriceps electromechanical delay foll (open full item for complete abstract)
    ... More

    Committee: Grant Norte PhD, AT, ATC, CSCS (Committee Chair); Neal Glaviano PhD, AT, ATC (Committee Member); Christopher Ingersoll PhD, AT, ATC, FACSM, FNATA, FASAHP (Committee Member) Subjects: Biomechanics; Kinesiology; Physical Therapy; Rehabilitation; Sports Medicine

  • 3. Ding, Yuan Mechanistic Understanding of CO2 Corrosion Inhibition at Elevated Temperatures

    Doctor of Philosophy (PhD), Ohio University, 2019, Chemical Engineering (Engineering and Technology)

    The mechanisms of corrosion inhibition of mild steel in high temperature and high pressure (HTHP) environments have been historically poorly understood. Due to its limited understanding, effective corrosion inhibition in HTHP wells is still very challenging. The purpose of this dissertation is to investigate the inhibition mechanisms of mild steel in the presence of two commonly used inhibitors (an imidazoline-type and a quaternary ammonium type (quat-type) inhibitor) at elevated temperatures. This comprehensive and systematic study provides insights on the selection of successful inhibition strategies at elevated temperatures. A series of experiments were first performed in a standard 2L glass cell at low to medium temperature (25C, 50C and 80C) to characterize adsorption kinetics over this temperature range, using the two selected inhibitors. These experiments included general corrosion inhibition tests using linear polarization resistance (LPR) measurements and direct determination of adsorption behavior using a quartz crystal microbalance (QCM). Both test methods yielded similar trends for the two inhibitors tested. This suggested that the loss of inhibition efficiency as temperature increased was a result of desorption being favored at higher temperatures. Novel high temperature corrosion inhibition tests were performed in a 4L autoclave specially designed to enable the injection of inhibitor under pressure, at elevated temperatures of 120C and 150C. In addition, the experimental setup and procedure were incrementally improved to minimize the formation of corrosion products and help identify the true effect of the inhibitors. For the imidazoline-type inhibitor, the inhibition efficiency continued to decrease with increasing temperature up to 120C and was completely masked by the rapid formation of Fe3O4 at 150C. The presence of Fe3O4 played a significant role on the corrosion inhibition at this temperature. The quat-type inhibitor completely lost its inhibi (open full item for complete abstract)
    ... More

    Committee: Marc Singer (Advisor) Subjects: Chemical Engineering

  • 4. Benito González, Ana V1-DERIVED RENSHAW CELLS AND IA INHIBITORY INTERNEURONS DIFFERENTIATE EARLY DURING DEVELOPMENT

    Doctor of Philosophy (PhD), Wright State University, 2011, Biomedical Sciences PhD

    Locomotor development is dependent on the maturation of spinal cord circuits controlling motor output, but little is known about the development of the spinal interneurons that control motoneuron activity. This study focused on the development of Renshaw cells (RCs) and Ia inhibitory interneurons (IaINs), which mediate recurrent and reciprocal inhibition, respectively, two basic inhibitory circuits for motorneuron control. Both interneurons originate from the same progenitor pool (p1) giving rise to ventral spinal embryonic interneurons denominated V1. V1-derived interneurons (V1-INs) establish local inhibitory connections with ipsilateral motoneurons and express the transcription factor engrailed-1. This characteristic permitted the generation of transgenic mice that were used in this study to genetically label V1 interneuron lineages from embryo to adult. Adult V1-derived Renshaw cells and IaINs share some similar properties, both being inhibitory and establishing ipsilateral connections; but differ in morphology, location in relation to motor pools, expression of calcium binding proteins (calbindin vs. parvabumin), synaptic connectivity and function. These differences are already present in neonates, therefore the purpose of this study was to determine possible embryonic differentiation mechanisms. Using 5‟-bromodeoxyuridine birth-dating we demonstrated that V1-INs can be divided into early and late born groups. The early group quickly upregulates calbindin iv expression and includes the Renshaw cells, which maintain calbindin expression through life. The second group includes many cells that postnatally upregulate parvalbumin, including IaINs. This later born group is characterized by upregulation of the transcription factor FoxP2 as they start to differentiate and is retained up to the first postnatal week in many V1-derived IaINs. In contrast, Renshaw cells express the transcription factor MafB that seems relatively specific to them within the V1-INs. Furtherm (open full item for complete abstract)
    ... More

    Committee: Francisco Alvarez PhD (Advisor); Paula Bubulya PhD (Committee Member); Timothy Cope PhD (Committee Member); David Ladle PhD (Committee Member); James Olson PhD (Committee Member) Subjects: Neurology

  • 5. Ayello, Francois Crude Oil Chemistry Effects on Corrosion Inhibition and Phase Wetting in Oil-Water Flow

    Doctor of Philosophy (PhD), Ohio University, 2010, Chemical Engineering (Engineering and Technology)

    The presence of water, even in small amounts, is often the cause of internal corrosion problems in crude oil transportation. Understanding the factors influencing steel pipeline corrosion rates is a safety as well as an economic matter. The objective of this dissertation is to quantify the effects that are known to have an influence on corrosion in crude oil-brine flow. The first effect is the corrosiveness of the brine. Crude oil's compounds can partition between the oil phase and the water phase to create brines with inhibitive or corrosive properties. The second effect is related to which phase wets the pipe wall. This depends on steel wettability and also on the flow pattern. Crude oil's polar compounds can change the steel hydrophilic surface nature. They also change the flow properties. The problem has been investigated at the Institute for Corrosion and Multiphase Technology at Ohio University on a small scale with specifically designed experiments as well as on a large scale, in a 60 meter-long flow loop loaded with 1600 gallons of oil and water. Results show that only a small percentage of the crude oil's complex chemistry controls its corrosion inhibitive and wettability properties. The knowledge generated from these experiments can be used as a useful reference for corrosion engineers and pipeline operators to maintain oil-water flow systems under corrosion-free conditions.
    ... More

    Committee: Srdjan Nesic PhD (Committee Chair); Michael Prudich PhD (Committee Member); Jeffrey Rack PhD (Committee Member); Howard Dewald PhD (Committee Member); Douglas Goetz PhD (Committee Member) Subjects: Chemical Engineering; Chemistry

  • 6. Lin, Kang-Yi The Dissolution of Iron from Automotive Steel Sheets in a Molten Zinc Bath and the Kinetics of the Nucleation and Growth of Dross Particles

    Master of Sciences, Case Western Reserve University, 2011, Materials Science and Engineering

    Hot-dip galvanizing (HDG) is a well-known process that increases the resistance of a steel strip to corrosion. Immersion of an automotive steel sheet in a galvanizing bath initiates a dissolution reaction. The flux of iron from the steel surface into the liquid zinc bath provides a driving force for the formation of an inhibition layer and the precipitation of dross particles. Such reactions involve the kinetics of nucleation and growth of intermetallic phases. This study addresses two main issues. First, the iron dissolution rate constant is governed by the solubility of iron in the liquid zinc under a metastable state between the pure bcc iron and the liquid phases. Secondly, a model for the nucleation and growth of precipitates can reveal the dynamics associated with intermetallic compound formation. The nucleation and growth model developed predicts that the inhibition layer covers 99.9% of the steel surface in 0.0011 second with the iron upersaturation of 0.56wt.% and the aluminum concentration of 0.20wt.% in a molten zinc bath at 460°C.
    ... More

    Committee: Gary Michal M. (Committee Chair); James McGuffin-Cawley D. (Committee Member); Mark DeGuire R. (Committee Member) Subjects: Metallurgy

  • 7. Frase, Hilary TOWARDS DEVELOPING SPECIFIC INHIBITORS OF THE ATP-DEPENDENT LON PROTEASE

    Doctor of Philosophy, Case Western Reserve University, 2007, Chemistry

    The ATP-dependent serine protease Lon is responsible for degrading damaged and certain regulatory proteins in vivo. The importance of Lon activity in bacterial pathogenicity has led to its emergence as a target in the development of novel antibiotics however no potent or specific inhibitors had been reported. This study focused on identifying a lead compound(s) for the development of potent inhibitors of the proteolytic activity of Lon. Steady-state kinetic characterization of the ATP and peptide hydrolysis activities of human and Salmonella enterica serovar Typhimurium (S. Typhimurium) Lon revealed no kinetic differences in ATP hydrolysis, but marked differences in substrate specificity. This suggests a peptide-based inhibitor may be developed which exploits these differences to target an inhibitor to a single homolog, minimizing cross-reactivity. Screening of commercially available peptide-based inhibitors highlight the utility of transition state analogs in inhibiting peptide hydrolysis. The peptidyl boronate, MG262, was the most potent inhibitor tested and was effective against both human and S. Typhimurium homologs (IC50 = 160 ± 10 nM and 122 ± 9 nM, respectively). Peptidyl boronates inhibit peptide hydrolysis through a two-step time-dependent mechanism with an overall Ki of ~ 20 nM. The first step is rapid and involves binding of the inhibitor and formation of a covalent adduct with the active site serine. A second slow step occurs in which the protease undergoes a conformational change or isomerization to enhance the interaction of the inhibitor with the proteolytic active site. Although inhibition of serine and threonine proteases by peptidyl boronates has been detected previously, Lon is the first protease which requires the binding of ATP to observe inhibition. Finally, the purification of the human homolog of the steroidogenic acute regulatory protein (StAR) is described. It is shown to be a substrate of human Lon and provides a starting point for the dev (open full item for complete abstract)
    ... More

    Committee: Irene Lee (Advisor) Subjects: Chemistry, Biochemistry

  • 8. Biswas, Avidipto CORROSION PROTECTION OF COPPER IN OILY MEDIA: MICROSCOPIC MECHANISMS

    Doctor of Philosophy, Case Western Reserve University, 2013, Materials Science and Engineering

    Tolyltriazole (TTAH) is an extensively used industrial-grade corrosion inhibitor (CI) for Cu. This PhD project developed an understanding on the microscopic mechanisms for the TTAH adsorption on Cu, and the effective protection against sulfide-attack in oily medium analogous to automotive lubricants. XPS and ToF-SIMS characterization were carried out on TTAH adsorption films formed on pristine Cu surfaces immersed in 0.01 wt. % TTAH oil solution at room temperature for immersion times ranging from 1 s to 0.6 Ms. Instantaneous complete coverage of the Cu surface by TTAH is revealed by ToF-SIMS. In Tougaard analysis of XPS spectra, the adsorption film morphology is best described by a uniform-layer model assuming a film thickness of 2.5 nm after 86.4 Ks. Depth-profiling in ToF-SIMS and ARXPS provide evidence for two distinct adsorption configurations for TTAH on Cu – polymerized layer, and monomer layer. TTAH adsorption is found to take place on Cu2O. Studying the time-dependent evolution of the surface film suggests a kinetics-controlled mechanism involving two competing reactions: oxidation of Cu to Cu2O, and TTAH-Cu complex formation. The TTAH-Cu complex formation proceeds at the cost of Cu2O. The structure and the chemical-composition of the surface film fluctuate with reaction time. Studying the corrosion of Cu in sulfide solution at 80C in the absence of TTAH suggests that the oxidation of Cu to Cu2O is kinetically favored over Cu corrosion by sulfide attack. The incubation time for the sulfide-attack decreases with increasing S concentration. Two distinct sulfide corrosion products are identified – Cu2SO4, forming at the oxide interface, and Cu2S, forming atop. The presence of TTAH significantly impedes the extent of sulfide-attack. At 80C, the TTAH adsorption film is substantially thicker than that of room temperature. This suggests that the rate-determining step for the formation of the adsorption film is the outward diffusion of Cu from the substrate. (open full item for complete abstract)
    ... More

    Committee: Frank Ernst (Advisor); Arthur Heuer (Committee Member); Jay Mann (Committee Member); Jim McGuffin-Cawley (Committee Member) Subjects: Automotive Materials; Engineering; Materials Science; Metallurgy

  • 9. Shamshabad, Vishwanutha Significance of Tubular Recycling Endosomes in Envelope Glycoprotein Trafficking and Particle Incorporation in HIV-1 Clade B Primary Isolates

    MS, University of Cincinnati, 2024, Medicine: Immunology

    Human Immunodeficiency virus (HIV-1) was discovered in 1983 from the lymph node sample of a patient at the Pasteur Institute and subsequently was found to be strongly linked to onset of AIDS. HIV-1 and its pathogenesis has been extensively studied now for decades. Many crucial components of the virus such as the viral replication machinery, proteins involved in replication and assembly, fusion of viral and host cells during infection, and many other aspects of the viral lifecycle have been defined. The HIV-1 envelope glycoprotein (Env) is an essential component of the virus, present on the lipid envelope of the virus and involved in cell membrane fusion and entry. An aspect of HIV-1 Env biology that is not well understood is how it interacts with host cell machinery to reach the site of particle assembly on the plasma membrane. This study investigates the involvement of tubular recycling endosome (TRE), a component of the cellular recycling machinery that is involved in transporting internalized cargo, in the trafficking of Env following endocytosis from the plasma membrane. In particular, this study addresses the interactions of primary isolates of HIV-1 Clade B Env with the TRE, using immunofluorescence staining and imaging of TRE markers. This study also focuses on the role of Phosphatidic Acid (PA) in modulating Env interaction with the TRE, and its regulation through phospholipase D (PLD). The effect of disruption of PA production through inhibition of PLD on Env-TRE colocalization was critically assessed using live cell and pulse-chase imaging along with monitoring of TRE markers. The effects of inhibition on infectivity and particle incorporation were evaluated after PLD inhibition. This study confirmed that primary isolate Env associates strongly with the TRE, and that inhibition of TRE formation through PLD inhibition disrupts Env trafficking. Findings here build on those with laboratory isolates of HIV-1 and provide a new potential therapeutic target to in (open full item for complete abstract)
    ... More

    Committee: Paul Spearman M.D. (Committee Chair); Claire Chougnet Ph.D. (Committee Member); Ian Lewkowich Ph.D. (Committee Member) Subjects: Immunology

  • 10. Morra, Allison Longitudinal Relations among Behavioral Inhibition, Error-Related Negativity, and Sex in Predicting Social Anxiety among Children

    Master of Arts, Miami University, 2024, Psychology

    Because social anxiety is highly prevalent among children and adolescents, it is important to study early risk factors in infancy in order to better understand a developmental pathway to social anxiety. Behavioral inhibition (BI), a tendency to hesitate or avoid novelty and uncertainty, is a leading risk factor appearing in infancy. BI has been linked to social anxiety through heightened response monitoring for threat or error. This error monitoring can be operationalized by measuring error-related negativity (ERN). Additionally, as social anxiety does not appear equally in men and women, it is important to understand if there is an underlying sex difference in neural components like ERN, and how sex determines pathways of risk involving ERN, that accounts for the difference in prevalence rates. This study (112 children, 44.6% female, 85.7% White, 95.5% non-Hispanic) proposed that infant BI will predict social anxiety symptoms in early childhood, through larger concurrent ERN, and that sex will moderate this mediation, with the relation between ERN and social anxiety symptoms being stronger among female children. Results did not support either hypothesis, but did find that BI predicted later social anxiety symptoms. Non-significant findings are discussed in the context of developmental psychopathology theory of social anxiety.
    ... More

    Committee: Elizabeth Kiel (Advisor); Aaron Luebbe (Committee Member); Robin Thomas (Committee Member) Subjects: Clinical Psychology

  • 11. Moon, Taylor Engineering Multi-Action Lipid Nanoparticle Platforms for Cancer Immunotherapy

    Doctor of Philosophy, Case Western Reserve University, 2024, Biomedical Engineering

    Cancer therapy has significantly advanced over the past few decades due to development of improved surgical technique, early detection, and novel therapy development. However, cancer remains one of the most lethal diseases due to metastasis, drug resistance, and recurrence. Immunotherapy holds the promise of utilizing the body's immune system to eliminate cancer cells. Immune checkpoint blockade therapy remains the most common utilization of immunotherapy in the clinical but yields varying degrees of success due to the massively immunosuppressed tumor microenvironment. Discovery of novel immune checkpoints and technology for targeting these checkpoints is critical for the advancement of cancer immunotherapy. The novel immune checkpoint protein VISTA (V-domain Immunoglobulin Suppressor of T cell Activation) impairs the toll-like receptor (TLR)-mediated activation of myeloid antigen presenting cells, promoting the expansion of myeloid derived suppressor cells, and suppressing tumor-reactive cytotoxic T cell function. Gene therapy targeting the VISTA checkpoint protein in conjunction with potent TLR agonists represents a safer yet potent alternative to antibody mediated cancer immunotherapy that has shown toxicity in the clinic. The overall objective of the work in this dissertation is to develop nanoparticle platforms for delivery of gene therapy mediate immune checkpoint blockade cancer immunotherapy regiments. First, a dual action lipid nanoparticle (Dual-LNP) that incorporates a VISTA-specific siRNA and a TLR9 agonist (unmethylated CPG) is developed. The Dual-LNP ensures co-delivery of both cargoes to tumor-infiltrating myeloid cells, leading to simultaneous silencing of VISTA and stimulation of TLR9. Next, the efficacy of the Dual-LNP was tested in multiple solid tumor models. The Dual-LNP treatment achieved a high cure rate in colon carcinoma MC38, melanoma B16F10, and YUMM1.7 models (83%, 60%, and 48%, respectively). Finally, investigation into the immune landsc (open full item for complete abstract)
    ... More

    Committee: Efstathios Karathanasis (Advisor); James Basilion (Committee Chair); Li Lily Wang (Committee Member); Andrew Shoffstall (Committee Member); William Schiemann (Committee Member) Subjects: Biomedical Engineering; Nanotechnology

  • 12. Meyering, Sigrid Some variables affecting retroactive inhibition /

    Master of Arts, The Ohio State University, 1964, Graduate School

    Committee: Not Provided (Other) Subjects:

  • 13. Rouse, Natasha Networks of Saddles to Visualize, Learn, Adjust and Create Branches in Robot State Trajectories

    Doctor of Philosophy, Case Western Reserve University, 2024, EMC - Mechanical Engineering

    In robot control, classical stability is formed around a stable point (attractor) or connected stable points (limit cycles). In contrast, connected saddles can be used to describe stable sequences of states. The connection between two saddles in phase space is a heteroclinic channel, and stable heteroclinic channels (SHCs) can be combined to form cycles and networks – stable heteroclinic networks (SHNs). While the stability and subperiod at each saddle have been mathematically predicted, the potential of SHCs as robot controllers has not been fully realized. To move from modelling to control, tools are needed to more precisely design and manipulate these systems. First, this manuscript expands the SHC-framework with a task space transformation inspired by a popular robot control framework – dynamic movement primitives (DMPs). Stable heteroclinic channel-based movement primitives (SMPs) have an intuitive visualization feature that allows users to easily initialize the controller using only the robot's desired trajectory in its task space. After applying SMPs to a simple robotic system, we characterize the SHC system variables in the larger SMP system, and use the SMP variable nu – the saddle value – for local, real-time controller tuning without compromising the overall stability of the system. Finally, we explore more complex, branching connected-saddle topologies as stable heteroclinic networks. SHCs and SHNs are stochastic systems where noisy external input, such as sensory input, can be used as the stochastic component of the system. For robots, we can use SHNs as a decision-making model where the external input directly drives which decision is made. Overall, this manuscript seeks to parametrize the saddle network frameworks SHCs and SHNs for user-friendly, robust, and versatile robot control. Networks of saddles exist as models for neural activity, neuromechanical models, and robot control, and they can provide further utility in the study and application of (open full item for complete abstract)
    ... More

    Committee: Kathryn Daltorio (Advisor); Roger Quinn (Committee Member); Hillel Chiel (Committee Member); Murat Cenk Cavusoglu (Committee Member) Subjects: Mechanical Engineering; Robotics

  • 14. Fausnaugh, Elisabeth The Impact of Mindfulness on the Development of Inhibition and Interference Control in Elementary Students

    Doctor of Education (Ed.D.), University of Findlay, 2024, Education

    Loss of instructional time due to student inattentiveness is a well-known problem (Godwin et al., 2016). Educators need effective and efficient methods to improve student attention and self-control for optimal learning. Research on the inclusion of mindfulness in schools is an emerging trend (Flook et al., 2010; Lam & Seiden, 2020; Ritter & Alvarez, 2020; Thierry et al., 2016; Van De Weijer-Bergsma et al., 2012). This mixed methods study investigated the impact of mindfulness-based practices on student inhibition and interference control skills; and explored student, teacher, and parent perceptions of including mindfulness-based practices in a school setting. Twenty-five third grade students from two classrooms at a suburban school in northwest Ohio participated in the 6-week mindfulness intervention. Quantitative data collected pre- and post-intervention for student inhibition indicated a moderate effect (d = 0.474) between the treatment and waitlist control group. Data collected for student interference control skills did not yield a significant effect between the treatment and waitlist control group (d = -0.012). Qualitative data gathered from interviews and surveys found positive social validity and acceptability from the perspective of students, teachers, and parents. Transference of mindfulness applications from school-to-home was reported by both students and parents. This study provides a model for introducing mindfulness in the educational environment, with the potential for further student benefit when applied in all settings. Implications for future research include exploring different measures of impact and gaining further qualitative research from all stakeholder's perspectives.
    ... More

    Committee: Kara Parker (Committee Chair); Kyle Wagner (Committee Member); Jon Brasfield (Committee Member) Subjects: Behavioral Psychology; Elementary Education

  • 15. He, Yi Effect of Intermittent Wetting on Corrosion Inhibition in Oil/Water Systems

    Doctor of Philosophy (PhD), Ohio University, 2024, Chemical Engineering (Engineering and Technology)

    In the oil and gas industry, long-distance transportation of petroleum and related products is usually carried out in large-diameter carbon steel pipelines. Oil and gas production involves the flow of a multiphase mixture of hydrocarbons, water and gas. As a result, various flow patterns can manifest themselves within liquid carrying pipelines, each influencing the potential for corrosion. Understanding and mitigating corrosion in such environments are key to ensuring the integrity and longevity of these critical assets. This study focused on intermittent surface wetting, a phenomenon where pipelines alternate between being oil-wet and water-wet due to changing production conditions. When the pipe is oil-wet, little to no corrosion should happen. However, the presence of corrosive species, e.g., CO2, H2S, and organic acids in the multiphase flow, results in severe corrosion of inner pipe walls, if its surface is water-wet. To solve this problem, the oil and gas industry employs corrosion inhibitors (CIs) – complex mixtures containing surfactant-type active ingredients. These CIs form protective layers on the metal surfaces to prevent electrochemical corrosion reactions at the water-metal interface. However, the effectiveness of CIs is not solely dependent on their chemical composition and concentration. This also depends on environmental factors such as pH, temperature, salinity, and surface conditions in oil/water flow. Moreover, in real-world oil/water flow scenarios, CIs inevitably partition between the hydrocarbon and aqueous 4 phases. This partitioning, often neglected in laboratory studies, is critical in evaluating inhibitor performance in practical settings since it can deplete the effective concentration of the inhibitor in the aqueous phase. Despite the importance of considering the oil phase and oil/water wetting, existing scientific literature often neglects these aspects in laboratory studies of CIs, which are very often conducte (open full item for complete abstract)
    ... More

    Committee: Marc Singer (Advisor); David Young (Committee Member); Srdjan Nesic (Committee Member); Eric Masson (Committee Member); Rebecca Barlag (Committee Member) Subjects: Chemical Engineering

  • 16. La Rosa, Chris Synthesis and Biological Evaluation of Select Anticancer Molecules and Antileishmanial Cytochrome P450 Inhibitors

    Doctor of Philosophy, The Ohio State University, 2024, Pharmaceutical Sciences

    Cancers and leishmaniasis are distinct diseases, but the effects of each on people and communities are similarly devastating. Cancers cause over 10 million deaths worldwide each year, and are so widespread that nearly every person has lost a loved one to them, myself included. Leishmaniasis primarily affects tropical countries and in many places where access to medical care is limited, and the visceral form of the disease requires medical treatment to increase chances of survival above 5%. Both cancers and visceral leishmaniasis are diseases that the human immune system alone often cannot overcome, so the continued research into treatments is crucial to develop new and better tools to fight against these diseases. This dissertation details drug discovery efforts for two different projects, one against each disease; chapter 1 introduces readers to each disease state, chapter 2 describes the synthesis and biological evaluation of anticancer compounds, and chapter 3 describes the synthesis and biological evaluation of antileishmanial compounds. Following the serendipitous discovery of an antileukemia hit compound with an arylimidamide-azole scaffold, a series of analogs was synthesized to evaluate modifications to the scaffold. A robust structure-activity relationship (SAR) was developed through the synthesis of these compounds, and analysis of this relationship pointed to specific chemical modifications to the scaffold which improved their anticancer potency. Combining these favorable modifications led to compounds with >4-fold improved potency compared to the parent compound. Among the most potent compounds in this iv series was 2.9k, which displayed an IC50 value of 100 nM against the acute myeloid leukemia (AML) cell line OCI-AML3. Promising compounds in this series were then further evaluated for broad anticancer activity, pharmacokinetic properties, and mechanism of action as described in chapter 2. The antileishmanial compounds described in this dissertation (open full item for complete abstract)
    ... More

    Committee: Karl Werbovetz (Advisor); Xiaolin Cheng (Committee Member); James Fuchs (Committee Member) Subjects: Biology; Chemistry; Organic Chemistry; Pharmaceuticals; Pharmacology; Pharmacy Sciences

  • 17. Byrnes, Daniel Individual Differences in False Memories in the Deese–Roediger–McDermott Paradigm: An Attention Control Account

    MA, Kent State University, 2024, College of Arts and Sciences / Department of Psychological Sciences

    This study examined the underlying mechanisms of false memories observed in the classic Deese–Roediger–McDermott (DRM) paradigm. Previous work indicates that greater working memory capacity and inhibition are associated with lower susceptibility to such false memories. We hypothesized that this may be, due to the closely related construct of attention control. We examined if individual differences in attention control accounted for variance in susceptibility to false memories, above and beyond inhibition and WMC alone. We used a standard DRM procedure in an individual differences approach to examine how working memory, inhibition, and attention control contribute to false memories as indicated by false word recall on the DRM task. Our results indicate that not only does attention control account for unique variance in susceptibility to the false memories, but it also may mediate the relationship between working memory capacity and DRM performance to a degree to which working memory becomes non-significant.
    ... More

    Committee: Christopher Was (Advisor); Maria Zaragoza (Committee Member); Jeffrey Ciesla (Committee Member); Dana Miller-Cotto (Committee Member); Philip Hamrick (Committee Member) Subjects: Cognitive Psychology; Psychology

  • 18. Ren, Shuai Effect of Corrosion Residues and Products of Mild Steel on Corrosion Inhibition Mechanisms in CO2 and H2S Environments

    Doctor of Philosophy (PhD), Ohio University, 2023, Chemical Engineering (Engineering and Technology)

    Internal corrosion of transmission tubulars is a huge concern in the oil and gas industry. Corrosion inhibitors (CIs) are often considered the first step in mitigating internal corrosion due to their high efficiency and cost-effectiveness. Yet, predicting the efficiency of corrosion inhibitors, developed and tested in a laboratory environment, in operating field conditions is very challenging. In addition, the presence of corrosion residues or corrosion products on the internal surface of tubular steels can significantly affect the inhibition performance of organic corrosion inhibitors. This aspect is only rarely considered when characterizing the performance of corrosion inhibitors. Therefore, understanding their effects on corrosion inhibition is of great benefit in applying corrosion inhibitors to tackle internal corrosion issues, particularly in aging pipelines. This work mainly focuses on evaluating the corrosion inhibition and revealing the inhibition mechanisms in the absence and presence of various corrosion residues or products, commonly found in oil and gas production. The first half of this work (Chapter 5 and 6) presents a methodology for the characterization of corrosion inhibitors and proposes several innovations to an inhibition prediction model, originally based on the work of Dominguez, et al.. An inhibitor model compound, i.e., tetradecyl phosphate ester (PE-C14), was synthesized in-house and characterized to obtain necessary parameter values required as inputs for the inhibition model. The updated inhibition model could predict steady state and transient corrosion inhibition behaviors with good accuracy. The second half of the presented work (Chapter 7, 8, and 9) focuses on the effects of corrosion residue (Fe3C) and products (FeCO3 and FeS) on corrosion inhibition and advances the understanding of the associated inhibition mechanisms. The galvanic effect caused by residual Fe3C on corrosion rate and inhibition efficiency was quantitatively (open full item for complete abstract)
    ... More

    Committee: Marc Singer (Advisor); Srdjan Nesic (Committee Member); David Young (Committee Member); Sumit Sharma (Committee Member); Katherine Cimatu (Committee Member); Katherine Fornash (Committee Member) Subjects: Chemical Engineering; Engineering; Materials Science

  • 19. Alzahrani, Mohammed NEWLY SYNTHESIZED mRNA ESCAPES TRANSLATIONAL REPRESSION DURING THE ACUTE PHASE OF THE MAMMALIAN UNFOLDED PROTEIN RESPONSE

    Doctor of Philosophy, Case Western Reserve University, 2023, Biochemistry

    Endoplasmic Reticulum (ER) stress, caused by the accumulation of misfolded proteins in the ER, elicits a homeostatic mechanism known as the Unfolded Protein Response (UPR). The UPR reprograms gene expression to promote adaptation to chronic ER stress. The UPR comprises an acute phase involving inhibition of bulk protein synthesis and a chronic phase of transcriptional induction coupled with the partial recovery of protein synthesis. However, the role of transcriptional regulation during the acute phase of the UPR is not well understood. In this study (Alzahrani et al., 2022), I analyzed the fate of newly synthesized mRNA encoding the protective and homeostatic transcription factor X-box binding protein 1 (XBP1) during this acute phase of UPR. Global translational repression induced during the acute UPR was documented and characterized by decreased translation and increased stability of XBP1 mRNA. My data suggest this stabilization of XBP1 mRNA is independent of new transcription. In contrast, newly synthesized XBP1 mRNA is shown to accumulate with long poly(A) tails and escapes translational repression during the acute phase of UPR. Inhibition of nascent RNA polyadenylation during the acute phase decreased cell survival with no effect in unstressed cells. During the chronic phase of the UPR, XBP1 mRNA abundance and long poly(A) tails decreased in a manner consistent with co-translational deadenylation. Finally, additional pro-survival, transcriptionally-induced genes show similar regulation, supporting the broad significance of the pre-steady state UPR in translational control during ER stress. I conclude that the biphasic regulation of poly(A) tail length during the UPR represents a previously unrecognized pro-survival mechanism of mammalian gene regulation.
    ... More

    Committee: Maria Hatzoglou (Advisor) Subjects: Molecular Biology

  • 20. Rahman, Monica Functional Consequences of Conjugating Polymers to Protein and Study of Biomarkers for Cell Death Pathway

    Doctor of Philosophy, Miami University, 2022, Chemistry and Biochemistry

    This work investigated the impact of polymer conjugation on the activity and stability profile of a lipase enzyme. An industrially important enzyme, Candida antarctica lipase B (CalB), was conjugated with different functional polymers, including those with hydrophilic, hydrophobic, cationic, and anionic characters. The study demonstrated enhanced CalB activity when conjugated with hydrophilic and cationic polymers against a hydrophobic substrate, p-nitrophenol palmitate (p-NPP), due to the possible non-covalent interaction between the polymer and the substrate. On the contrary, conjugating with hydrophobic polymer showed significant activity inhibition, likely due to binding to the catalytic site. Hence, CalB conjugation with this diverse range of polymers demonstrated the significance of polymer composition, polymer-substrate interactions, and protein-polymer interactions in deciding protein catalytic performance. With this in mind, this dissertation also showed the manipulation of these protein-polymer interactions to tune a protein's catalytic performance in different pH environments. In addition, this thesis also explored work focusing on combating coronavirus. In one project, the receptor-binding domain of spike protein of SARS-CoV-2 was modified with different polymers to explore the sensitivity of interactions between the modified RBD and ACE2 protein, which may be beneficial in the downstream development of inhibitors targeting the RBD-ACE2 interaction. In another project, spike binding peptide (SBP1) was immobilized into a covalent crosslinked network system to develop a novel peptide-functionalized network to capture the spike protein of coronavirus. The development of such functionalized network could provide us materials with potential antiviral properties, which can provide us the opportunity to mitigate coronavirus spread. Hence, this thesis work highlighted different functional consequences of protein-polymer interaction ranging from tuning activity a (open full item for complete abstract)
    ... More

    Committee: Rick Page (Advisor); Dominik Konkolewicz (Advisor); C. Scott Hartley (Committee Chair); Gary Lorigan (Committee Member); Jason Berberich (Committee Member) Subjects: Analytical Chemistry; Biochemistry; Polymer Chemistry