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Integrating Health Equity Into Implementation Science To Advance Chronic Disease Prevention And Control, Callie Walsh-Bailey Jan 2024

Integrating Health Equity Into Implementation Science To Advance Chronic Disease Prevention And Control, Callie Walsh-Bailey

Brown School Theses and Dissertations

Marginalized populations are inequitably burdened by chronic diseases such as diabetes, heart disease, obesity, and cancer. The goal of health equity work is to ensure all people have a fair and just opportunity to achieve optimal health. Implementation science has made health equity a greater focus and priority in recent years. There has been a proliferation of guidance on what implementation science needs to do to advance equity. However, the field currently lacks specific, actionable guidance on how to integrate equity. The overarching goal of this dissertation is to synthesize conceptual and theoretical underpinnings regarding health equity and bring them …


Information-Rich 6d Single-Molecule Imaging Design Using Optimization, Tingting Wu Dec 2023

Information-Rich 6d Single-Molecule Imaging Design Using Optimization, Tingting Wu

McKelvey School of Engineering Theses & Dissertations

When studying biochemical processes, localizing the targets alone will not paint a complete picture. We also need techniques to probe how biomolecules interact with one another, including how molecules are organized into larger structures, how they are oriented with respect to surrounding molecules, and how local chemical parameters, like pH and hydrophobicity, vary spatially and temporally. My dissertation focuses on single-molecule orientation localization microscopy (SMOLM, Chapter 1). The objective is to develop imaging techniques for measuring how molecules are oriented with respect to their surrounding molecules, namely, 3D orientation. Achieving optimal imaging performance requires careful design of both the forward …


Multi-Layer Strip Ionization Chamber For Proton Quality Assurance And Imaging, Shuang Zhou Dec 2023

Multi-Layer Strip Ionization Chamber For Proton Quality Assurance And Imaging, Shuang Zhou

McKelvey School of Engineering Theses & Dissertations

Proton therapy is the most advanced radiation treatment modality. Proton treatment is delivered via pencil beam scanning (PBS) technique, in which a pencil beam scans the target spot-by-spot and layer-by-layer. An effective quality assurance (QA) device is needed to verify the quality of treatment dose delivery. Current clinical practice employs films or a two-dimensional (2D) detector to measure the dose at one or a few arbitrarily selected depths, which is insensitive to delivery error and time-consuming. A 3D dosimeter that can measure the 3D dose distribution is needed to improve the effectiveness and efficiency of proton QA. Furthermore, preclinical studies …


Divergent Self-Assembly Of Block Heterochiral Stereoisomer Arrays, Conor Louis O'Neill Dec 2023

Divergent Self-Assembly Of Block Heterochiral Stereoisomer Arrays, Conor Louis O'Neill

McKelvey School of Engineering Theses & Dissertations

The autonomous organization of parts into ordered architectures, or biomolecular self-assembly, is an elementary natural process that defines and guides the construction and function of living organisms. This phenomenon has emerged as a potent tool for the creation of novel biomaterials, with peptide-based instances benefitting from intrinsic modularity, ease of de novo design and synthesis, biocompatibility, and chemical versatility. These properties enable methodical modifications that generate suprastructures with a wide variety of morphologies and functionalities, supporting a broad range of biomedical applications. Further, the chiral nature of amino acids permits synthesis of either left- or right-handed peptides; in recent years, …


Mechanisms And Prevention Of Antibiotic Resistant Organism Spread In Hospitals, Erin P. Newcomer Dec 2023

Mechanisms And Prevention Of Antibiotic Resistant Organism Spread In Hospitals, Erin P. Newcomer

McKelvey School of Engineering Theses & Dissertations

Our quest as a species to treat and prevent disease has led us to develop medical care that would have been inconceivable even one century ago. However, as we learn to overcome previous roadblocks, new hurdles that we hadn’t even considered continue to present themselves. Once we learned to understand the germ theory of disease, we sought treatments for infectious diseases, which led us to the development of antibiotics. Antibiotics are responsible for saving countless lives and have ushered in the advances in other fields of medicine like cancer treatment and surgery. Now, antibiotic resistance threatens our ability to treat …


The Development And Validation Of Novel Imaging Biomarkers For Uterine Contraction, Cervix And Placenta In Pregnancy, Wenjie Wu Dec 2023

The Development And Validation Of Novel Imaging Biomarkers For Uterine Contraction, Cervix And Placenta In Pregnancy, Wenjie Wu

McKelvey School of Engineering Theses & Dissertations

Annually, nearly half a million neonates in the United States and 15 million globally are born preterm, defined as prior to 37 completed weeks of gestation. These births present elevated risks of neonatal mortality and long-term neurological deficits. The predominant obstetric precursors of preterm birth (PTB) include spontaneous preterm labor (45%), medically-indicated deliveries (30%), and preterm premature rupture of membranes (PPROM, 25%). Each precursor is associated with distinct physiological or structural alterations such as uterine contractions, placental dysfunction, or cervical insufficiency. Current methodologies for monitoring uterine contractions, such as intrauterine pressure catheters and electrohysterography, possess limitations in spatial resolution, coverage, …


Improving And Integrating Quantitative Single Cell Spatial Biology For Theranostic Medicine, Peng Lu Dec 2023

Improving And Integrating Quantitative Single Cell Spatial Biology For Theranostic Medicine, Peng Lu

McKelvey School of Engineering Theses & Dissertations

Disease states are the result of a complex interplay of many different cell types interacting in close proximity in the context of often heterogeneous tissues. Alpha particles are drawing intense research and clinical interest because of their potent cytotoxic effects and their short path lengths. Analyzing the dose distribution and tissue micro-environment for alpha therapy plays a key role in predicting the efficacy of this targeted radiotherapy. However, to date there have been no direct on-tissue analytical methods for alpha dose distributions and the corresponding tissue microenvironments. Therefore, we have developed a pipeline to overcome this limitation by utilizing quantitative …


Estimating And Detecting Slow-Wave Events In Eeg Signals, Zhenghao Xiong Dec 2023

Estimating And Detecting Slow-Wave Events In Eeg Signals, Zhenghao Xiong

McKelvey School of Engineering Theses & Dissertations

Slow wave activity (SWA) is an electroencephalogram (EEG) pattern commonly occurring during anesthesia and deep sleep, and is hence a candidate biomarker to quantify such states and understand their connection to various phenotypes. SWA consists of individual slow waves (ISW), high-amplitude deflections lasting for approximately 0.5 to 1 second, and occurring quasi-periodically. This latter fact poses a challenge for conventional power spectral density EEG analysis methods that perform best when there is persistency of oscillatory activity. In this work, we pursue a time-domain detection framework for identifying and quantifying ISWs as a metric for SWA. Our method works, in essence, …


Consistent Across Situations? A Person Specific Approach To Examining A Long-Standing Paradox., Muchen Xi Dec 2023

Consistent Across Situations? A Person Specific Approach To Examining A Long-Standing Paradox., Muchen Xi

Arts & Sciences Electronic Theses and Dissertations

Bem and Allen (1974) address the person situation debate by proposing that there are some people behave more consistently, which can be better “explained” try personality traits, than others who are more influenced by situations. However, with failures to directly replicate Bem and Allen’s study, the existence of individual difference in cross situation consistency of behaviors remaining unclear. The current study addressed open questions that arose from the personality consistency debate by employing Mixed Effect Location Scale Model (MELSM) in an intensive longitudinal study. We found 1) there are individual difference in the overall behavioral consistency across situations; 2) there …


Grasping Type Affects Configural Encoding In Visual Working Memory, Shinhae Ahn Dec 2023

Grasping Type Affects Configural Encoding In Visual Working Memory, Shinhae Ahn

Arts & Sciences Electronic Theses and Dissertations

Previous research has shown that different grasping actions selectively influence the processing of simple visual features based on their relevance to the specific action. However, it remains uncertain if this interaction extends to abstract and higher-order information, such as global configuration extracted from an array of visual objects. The present study aimed to investigate the impact of different grasping types on the processing of configural shape information in visual working memory (VWM). In Experiment 1, participants engaged in a VWM change detection task while adopting either power- or precision-grasping postures. The availability of configural shape information was manipulated through the …


A Mega-Study Of Stereotypes And Attitudes Toward Nationality Groups In The United States, Ayse Selin Toprakkiran Dec 2023

A Mega-Study Of Stereotypes And Attitudes Toward Nationality Groups In The United States, Ayse Selin Toprakkiran

Arts & Sciences Electronic Theses and Dissertations

The culture and demographics of the United States have been greatly influenced by numerous immigrant nationality groups, which continue to play a vital role in society. To understand how nationality groups are perceived in the United States, we asked residents to report stereotypes and attitudes toward 28 nationality groups and 6 racial/ethnic groups (N = 7,050). Our findings showed various patterns across 15 stereotypes, grouped under warmth, status, Americanness, and political orientation dimensions. Warmth-related stereotypes and attitudes varied widely across groups and did not follow a discernible pattern. Status-related stereotypes of Asian Americans and East Asian nationality groups were consistently …


Characterizing The Relationship Between Accented Speech Intelligibility And Listening Effort, Mel Mallard Dec 2023

Characterizing The Relationship Between Accented Speech Intelligibility And Listening Effort, Mel Mallard

Arts & Sciences Electronic Theses and Dissertations

Unfamiliar accents can make speech communication difficult, both by reducing speech intelligibility and by increasing the effort listeners must put forth to understand speech. However, these two constructs, while related, are independent: for example, two 100% intelligible utterances may require different amounts of effort to accurately process. To better characterize the relationship between intelligibility and effort, this study presents speakers of four intelligibility levels (one natively-accented English speaker, and three Mandarin-accented English speakers) within a dual-task paradigm (featuring a vibrotactile secondary task) to measure listening effort. We found a negative nonlinear relationship between intelligibility and effort, with the steepest slope …


Superconducting Non-Reciprocity Based On Time-Modulated Coupled-Resonator Systems, Yi Zhuang Dec 2023

Superconducting Non-Reciprocity Based On Time-Modulated Coupled-Resonator Systems, Yi Zhuang

McKelvey School of Engineering Theses & Dissertations

No abstract provided.


Modeling Of Functional Gene Regulation Through Machine Learning And Deep Learning Methods, Yuhao Chen Dec 2023

Modeling Of Functional Gene Regulation Through Machine Learning And Deep Learning Methods, Yuhao Chen

McKelvey School of Engineering Theses & Dissertations

Genes are specific sequences of nucleotides within the genome that undergo transcription to generate products that can diffuse throughout the cell. These gene products can take the form of either proteins or RNAs and play crucial roles in virtually all cellular functions, encompassing structural support, enzymatic activities, and signaling functions. An essential focus of contemporary biological research revolves around unraveling the functions of genes and their resulting products across different organisms. One primary means to conduct this research is through the regulation of gene expression. MicroRNAs (miRNAs), short single-stranded non-coding RNAs, play vital roles in gene expression regulation. Both computational …


Commercial Adsorbents For Co2 Removal For Biogas Upgradation: An Experimental Study, Aakriti Bagla Dec 2023

Commercial Adsorbents For Co2 Removal For Biogas Upgradation: An Experimental Study, Aakriti Bagla

McKelvey School of Engineering Theses & Dissertations

No abstract provided.


Advanced Diffusion Mri Technique And Applications In Placenta And Brain, Zhexian Sun Dec 2023

Advanced Diffusion Mri Technique And Applications In Placenta And Brain, Zhexian Sun

McKelvey School of Engineering Theses & Dissertations

Among a series of contrasts of MRI, diffusion MRI (dMRI) is different from conventional MRI by its ability to capture information about the random movement of water molecules and their interaction with local tissue microstructures. This capability holds the potential to reveal intricate subvoxel microstructural information linked to pathological changes, offering potential imaging biomarkers. A higher-order diffusion analysis model helps to yield more accurate and specific parameters but requires more extensive parameter tuning and higher image quality. In this study, we firstly fine-tuned the previously developed diffusion basis spectrum imaging (DBSI) method to strike a balance between efficiency and accuracy …


Predictive Looking And Predictive Looking Errors In Everyday Activities, Sophie Su Dec 2023

Predictive Looking And Predictive Looking Errors In Everyday Activities, Sophie Su

Arts & Sciences Electronic Theses and Dissertations

People spontaneously segment continuous streams of experiences into distinct episodes. Prediction errors are theorized to drive segmentation. However, existing studies exploring the relationship between prediction error and event segmentation lack a continuous measure of prediction error during naturalistic perception and often fail to distinguish between prediction error and prediction uncertainty. Do moment-by-moment fluctuation of prediction errors, not prediction uncertainty during naturalistic event perception correlate positively with segmentation probabilities? To tackle this question, we harnessed the predictive nature of eye movements and introduced a predictive looking model. In this model, individuals’ prior gaze patterns act as predictors for critical features in …


The Effect Of Material Nonlinearity On Stress Concentrations At A Bi-Material Interface, Jin Qian Dec 2023

The Effect Of Material Nonlinearity On Stress Concentrations At A Bi-Material Interface, Jin Qian

McKelvey School of Engineering Theses & Dissertations

No abstract provided.


Improving And Integrating Quantitative Single Cell Spatial Biology For Theranostic Medicine, Peng Lu Dec 2023

Improving And Integrating Quantitative Single Cell Spatial Biology For Theranostic Medicine, Peng Lu

McKelvey School of Engineering Theses & Dissertations

Disease states are the result of a complex interplay of many different cell types interacting in close proximity in the context of often heterogeneous tissues. Alpha particles are drawing intense research and clinical interest because of their potent cytotoxic effects and their short path lengths. Analyzing the dose distribution and tissue micro-environment for alpha therapy plays a key role in predicting the efficacy of this targeted radiotherapy. However, to date there have been no direct on-tissue analytical methods for alpha dose distributions and the corresponding tissue microenvironments.

Therefore, we have developed a pipeline to overcome this limitation by utilizing quantitative …


Discounting Of Delayed And Probabilistic Outcomes Across The Adult Lifespan, Haoran Wan Dec 2023

Discounting Of Delayed And Probabilistic Outcomes Across The Adult Lifespan, Haoran Wan

Arts & Sciences Electronic Theses and Dissertations

Intertemporal and risky decision-making predicts many problem behaviors that also decline with age, raising the question: Do intertemporal and risky decisions change with age? Despite the theoretical and empirical importance, the literature under both rubrics reveals inconsistent findings. Some studies suggest that these inconsistencies may be due to the presence of unassessed demographic differences. The present study examined age differences, evaluating the role of demographic variables in intertemporal and risky choice of gains and losses using the discounting framework. Four experiments were conducted, each with one of the four types of discounting: discounting of delayed gains, discounting of delayed losses, …


An Apparatus To Quantify Lengthwise Flexural Rigidity Profiles Of Endovascular Devices, Charles B. Suskin Dec 2023

An Apparatus To Quantify Lengthwise Flexural Rigidity Profiles Of Endovascular Devices, Charles B. Suskin

McKelvey School of Engineering Theses & Dissertations

Endovascular procedures require access to distal anatomical sites through the vasculature using catheters and guidewires. Quantitative frameworks for device behavior during procedures hold the potential to drive device design through greater understanding of the mechanical behavior of endovascular devices, and offer the potential to personalize care based on a patient's particular vascular anatomy. However, data that would facilitate this technology are lacking, partly due to undisclosed material properties from manufacturers and partly due to the intricate variations along the length of each device due to material changes and the intersections between them. We developed a three-point bend test methodology on …


Enhanced Fabrication Of Microdroplet Generator Nozzle Arrays: Optimizing Koh Etching For Microfluidic Applications, Hongyu Bai Dec 2023

Enhanced Fabrication Of Microdroplet Generator Nozzle Arrays: Optimizing Koh Etching For Microfluidic Applications, Hongyu Bai

McKelvey School of Engineering Theses & Dissertations

Ultrasonic microdroplet generators are useful devices with broad applications ranging from aerosolized drug delivery to three-dimensional (3D) printing-based additive manufacturing. One such technology comprises a microfabricated array of nozzles with droplet production driven by a piezoelectric transducer. The present study focuses on refining a critical fabrication step, anisotropic wet etching of pyramidal nozzles using a basic potassium hydroxide (KOH) solution. Given the integral role of nozzle geometry in device operation, high-precision techniques including Reactive Ion Etching (RIE), Deep Reactive Ion Etching (DRIE), and KOH wet etching were employed. A tapering geometry is preferred for acoustic wave focusing and efficient droplet …


Design Of Human Serum Albumin And Adenovirus Conjugation Via Catcher/Tag Molecular Glue, Peijie Zhao Dec 2023

Design Of Human Serum Albumin And Adenovirus Conjugation Via Catcher/Tag Molecular Glue, Peijie Zhao

McKelvey School of Engineering Theses & Dissertations

Adenovirus (Ad) has been the ideal cargo delivery mechanism, and its moderate immunological response makes it ideal for in vivo gene therapies since its discovery in 1953. However, the robust immunogenicity of the Ad capsid and low vaccine absorption via mucous membranes and epithelium put a limit on the process of developing intranasal vaccines. Efforts are being made to enhance the effectiveness of Ad vectors and numerous studies have demonstrated the remarkable capacity of human serum albumin (HSA) to extend plasma half-life and facilitate targeted intranasal delivery. In this study, we devised an innovative method for employing the Catcher/Tag molecular …


Real-Time Analysis Of Aerosol Size Distributions With The Fast Integrated Mobility Spectrometer (Fims), Daisy Wang Dec 2023

Real-Time Analysis Of Aerosol Size Distributions With The Fast Integrated Mobility Spectrometer (Fims), Daisy Wang

McKelvey School of Engineering Theses & Dissertations

The Fast Integrated Mobility Spectrometer (FIMS) has emerged as an innovative instrument in the aerosol science domain. It employs a spatially varying electric field to separate charged aerosol particles by their electrical mobilities. These separated particles are then enlarged through vapor condensation and imaged in real time by a high-speed CCD camera. FIMS achieves near 100% detection efficiency for particles ranging from 10 nm to 600 nm with a temporal resolution of one second. However, FIMS’ real-time capabilities are limited by an offline data analysis process. Deferring analysis until hours or days after measurement makes FIMS' capabilities less valuable for …


Projecting, Persuading, & Protecting: A Mixed Methods Analysis Of Adult Children’S Predictions Of Parents’ Quality-Of-Life Valuations In Serious Illness States, Jessica Hahne Dec 2023

Projecting, Persuading, & Protecting: A Mixed Methods Analysis Of Adult Children’S Predictions Of Parents’ Quality-Of-Life Valuations In Serious Illness States, Jessica Hahne

Arts & Sciences Electronic Theses and Dissertations

Older adults often face complex serious illness decisions and involve their adult children as shared or surrogate decision makers. However, previous research asking family members to predict older adults’ treatment preferences in serious illness situations typically shows poor concordance with older adults’ actual preferences. In the current mixed methods analysis, we surveyed older adults (n = 38) on their health state valuations in five serious illness scenarios. Two of their adult children (n = 76) predicted their parent’s preferences. Families also participated in a semi-structured conversation to discuss their preferences and predictions.

Quantitative analyses showed that parents’ average valuations were …


Virtue-Driven Leadership: Powering Excellence In Organizations, Joseph Scherrer Dec 2023

Virtue-Driven Leadership: Powering Excellence In Organizations, Joseph Scherrer

Arts & Sciences Electronic Theses and Dissertations

In this thesis, I seek to answer the question “What makes a good leader?” I approach this question systematically, starting in Chapter 1 by asking “What is Leadership?” In attempting to formulate a response, I find that the concept is slipperier than it first appears and difficult to pin down. All the same, I construct a thematic, contextually pertinent definition that provides reasonable precision for the purposes of this study. In Chapter 2, I present a representative survey of the social-scientific academic literature in order to establish the prospect that a philosophy of virtuous leadership can be empirically validated in …


Using Retrieval Practice, Variability, And Spacing To Facilitate Understanding Of Complex Information, Rachel Peirce Dec 2023

Using Retrieval Practice, Variability, And Spacing To Facilitate Understanding Of Complex Information, Rachel Peirce

Arts & Sciences Electronic Theses and Dissertations

Combining the learning strategies of retrieval practice and variability has been shown to be effective in student learning (Butler et al., 2017; Pan & Rickard, 2018), but the temporal structuring of these learning strategies (i.e., massing versus spacing of practice) may benefit or hinder learning. Study 1 investigated whether the benefits of variable retrieval practice relative to repeated retrieval practice that occurs with massed practice extends to spaced practice. Participants watched geology videos that contained a total of 12 concepts, and then either answered three questions or read three study points about each concept. Each of the three questions and …


Emotion Regulation Flexibility: Investigating Perseverative Thinking As A Novel Context, Beatris Garcia Dec 2023

Emotion Regulation Flexibility: Investigating Perseverative Thinking As A Novel Context, Beatris Garcia

Arts & Sciences Electronic Theses and Dissertations

Emotion regulation (ER) flexibility is a rapidly evolving field within affective science. Current advances have identified context sensitivity as a leading method for measuring ER flexibility, largely focusing on affectivity and situational control as markers of context. In this study, we propose an innovative approach to expand the list of contextual features tied to ER flexibility by using a framework based on Perseverative Thinking (PT). We examined seven PT dimensions, including pleasantness, repetitiveness, self-focus, other-focus, certainty, controllability, and temporal orientation, along with six ER strategies: reappraisal, acceptance, problem solving, expressive suppression, distraction, and cognitive avoidance. Once a day over the …


How Prefixation, Onset Length, And Coda Length Determine Lexical Stress Assignment When Reading Aloud, Kayla Hensley Dec 2023

How Prefixation, Onset Length, And Coda Length Determine Lexical Stress Assignment When Reading Aloud, Kayla Hensley

Arts & Sciences Electronic Theses and Dissertations

Lexical stress, or which syllable is emphasized in a multisyllabic word, can provide important cues for speech segmentation, lexical class, and reading acquisition. Despite this, much of the literature on reading has focused on single syllable words, neglecting the role that stress can play. In this project, I examine the role of prefixation, onset and coda length in assigning stress in disyllabic words when reading aloud. Study 1 is a corpus analysis of English words with grade level information to replicate the model developed by Treiman et al. 2020 and check for age differences. There were no significant differences on …


Development And Objective Task-Based Evaluation Of Computational Methods For Clinical Spect, Md Ashequr Rahman Oct 2023

Development And Objective Task-Based Evaluation Of Computational Methods For Clinical Spect, Md Ashequr Rahman

McKelvey School of Engineering Theses & Dissertations

Single-photon emission computed tomography (SPECT) is widely used for imaging radiotracer distribution in vivo. In several SPECT applications, patients are administered a significant amount of radiation dose and thus, it is desirable to reduce the dose level. However, reducing the dose level results in low-count data, which leads to a decrease in image quality in terms of the performance on clinical tasks. Moreover, SPECT in applications such as alpha-particle radiopharmaceutical therapies (α-RPT) is inherently count limited. Methods to improve the image quality in low-dose/low-count settings for SPECT images are thus much needed. The goal of this dissertation is to develop …