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Enhancing Medical Image Utility: Dataset Distillation and Endoscopic Panoramic Reconstruction
No full textThe advancement of medical imaging plays a pivotal role in diagnostics, yet challenges such as data sharing constraints and limited field-of-view hinder its full potential. This thesis explores two critical areas: dataset distillation for medical imaging and endoscopic panoramic reconstruction.
Dataset distillation offers a promising avenue for reducing data size while retaining diagnostic efficacy, addressing challenges in data privacy and storage efficiency. Through extensive experiments on multiple medical datasets, we assess the feasibility of state-of-the-art distillation techniques, demonstrating that condensed datasets can achieve near-equivalent model performance compared to full datasets. Moreover, we introduce predictive indicators to evaluate distillation effectiveness across various imaging modalities, paving the way for more efficient and secure medical data sharing.
In parallel, we propose an automatic image unfolding and stitching framework for esophageal endoscopy to overcome the limitations of narrow-field imaging. Our method integrates depth-based unfolding, feature-matching techniques (LoFTR, SIFT, ORB), and a novel Density-Weighted Homography Optimization (DWHO) algorithm to enhance image alignment and stitching accuracy. By reconstructing high-quality panoramic views of the esophagus, our approach improves diagnostic clarity and clinical decision-making.
Together, these contributions address critical bottlenecks in medical imaging by enhancing data efficiency and visualization fidelity, thereby advancing computational approaches for medical diagnostics and collaborative research
The Role of Prostanoid Signaling in Inflammatory Responses Relevant to Diabetic Retinopathy
No full textDiabetic retinopathy (DR) is the leading cause of blindness in working-age Americans, and its disease burden continues to rise as the global prevalence of diabetes grows. Current therapies for DR address only late-stage disease relevant to retinal neovascularization when irreparable retinal damage from aberrant blood vessel growth has already begun. Herein, we investigated prostanoid signaling as a contributor to the inflammatory responses that occur early in DR pathology to identify novel, targeted therapeutic options addressing disease before the most severe risks to vision ensue. In vitro analyses were performed using primary human Müller glia (hMG), primary human retinal microvascular endothelial cells (hRMEC), and primary human retinal pigment epithelial cells (RPE) or a relevant RPE cell line. After stimulating retinal cells in conditions modeling hyperglycemia, dyslipidemia, and chronic inflammation occurring systemically in patients with diabetes, we found that hMG produced highly elevated levels of one prostanoid, PGE2, whereas hRMEC produced elevated levels of PGF2α most consistently. The receptor-specific effects of prostanoid signaling were then evaluated in cell behavior assays relevant to early DR. Proinflammatory cytokine production in hMG was amplified by both PGE2-EP2 and PGF2α-FP signaling. Leukocyte adhesion to hRMEC was increased by PGF2α-FP signaling. Inner blood-retina barrier function modeled by hRMEC was enhanced by PGE2-EP4 signaling, yet, in contrast, outer blood retina barrier function modeled by cultured RPE was weakened by PGE2-EP2 signaling. Together, these results provide initial characterizations of the inflammatory effects of prostanoid signaling pathways in single cell type behaviors that model early DR progression. Modulation of individual prostanoid signaling pathways via selective agonists and/or antagonists may provide a valuable therapeutic strategy for DR management at the earliest stages of disease
Metabolic Reprogramming of the Irradiated Mammary Gland Microenvironment in Breast Cancer Recurrence
No full textTriple-negative breast cancer (TNBC) is a highly aggressive and metastatic subtype of breast cancer that cannot be targeted with traditional hormone therapies. Radiation therapy (RT) is routinely used in the clinic to reduce the incidence of recurrent disease; however, patients with TNBC still experience disproportionately high locoregional recurrence rates compared to other breast cancer subtypes. Pre-clinical models have suggested that locoregional recurrence may be due to the interactions of RT-resistant cancer cells or circulating tumor cells with the RT-damaged mammary gland tissue following surgical resection of the tumor. RT-resistant and circulating tumor cells are known to have altered metabolic profiles that aid in their survival following treatment; however, little is known about how RT influences the metabolic profiles of stromal cells of the mammary gland such as fibroblasts, adipocytes, and endothelial cells. Understanding metabolic alterations in these cells following RT could provide insights into TNBC recurrence mechanisms. In this dissertation, I demonstrate that irradiated fibroblasts undergo a dramatic metabolic shift that is characterized by lipid accumulation, changes in mitochondrial morphology, and high levels of mitochondrial respiration that is supported by an increase in fatty acid oxidation. These processes are accompanied by an increase in autophagic flux which regulates the fibroblast’s metabolic response to radiation damage. I then demonstrate that irradiated fibroblasts undergo a mitochondrial stress response over time that induces a complex secretory profile of lactate, mitokines, and cytokines that is altered through autophagy inhibition. These changes induce an aggressive phenotype in TNBC cells, as demonstrated through increased migration and tumorsphere growth that can be mitigated when autophagy is blocked in irradiated fibroblasts. Finally, I demonstrate how adipocytes and endothelial cells, other important mammary gland stromal cells, interact with each other following RT to influence the wound healing response. These observations lead to the development of a novel in vitro hydrogel system in which adipocyte spheroids are co-cultured with endothelial cells and fibroblasts, enabling the study of stromal-immune cell interactions post-RT. Ultimately, the work in this dissertation provides important mechanistic insight into metabolic pathways that can be targeted in combination with RT to reduce recurrent disease for TNBC patients
A Synthetic Receptor Platform to Engineer Mesenchymal Stromal Cells for Osteoarthritis Detection and Guided Articular Cartilage Regenerative Medicine
No full textOsteoarthritis (OA) treatment remains a significant clinical challenge due to the absence of disease-modifying therapies. Current approaches are primarily palliative, providing symptom relief or temporary efficacy without addressing the underlying pathology, including the degradation of articular cartilage. Mesenchymal stromal cells (MSCs) have shown promise for cartilage repair, but their therapeutic effects remain inconsistent and insufficiently targeted to OA pathology, limiting their clinical utility. To address these shortcomings, we engineered a synthetic Notch (synNotch) receptor that allows precise, spatially controlled activation of MSCs in response to type II collagen (CII), an extracellular matrix component exposed during OA-associated cartilage degradation. This system enables receptor activation and transgene expression only upon direct engagement with CII-coated substrates, including both adsorbed CII and enzymatically degraded, primary cartilage tissue. Notably, engineered CII-synNotch MSCs produce supraphysiologic levels of pro-anabolic transforming growth factor-beta 3 (TGF-β3) and anti-catabolic interleukin-1 receptor antagonist (IL-1Ra), two key modulators of OA pathology. Sustained transgene production facilitated both anabolic gene expression of MSCs and modulation of IL-1-associated inflammation in chondrocyte co-cultures. However, in vivo, CII-synNotch cells exhibited ligand-independent activation, prompting further investigation into underlying proteolytic and mechanical mechanisms of receptor activation in the joint. We investigated receptor-mediated activation in arthritic joints using canonical synNotch receptors and alternative receptor designs. While these studies offered insights into factors contributing to off-target activation, further optimization is required to enhance receptor specificity and achieve controlled activation that is aligned with OA progression. The findings presented here establish a foundation for synthetically regulated, engineered cell therapies that respond to OA-specific pathological features for programmed therapeutic effects
Paperless Discharge in the Emergency Department
No full textSchool of Nursing Doctor of Nursing Practice Program ProjectPurpose:
The purpose of this project is to implement a paperless discharge process for lower acuity patients in the ED will a decrease in the number of minutes in the overall LOS in the ED and decrease in the number of minutes from disposition to depart in the ED. A decrease in overall LOS will decrease ED overcrowding by decreasing patient wait time to be seen by provider in the ED.
Methods:
PLAN: Project Design: A non-research pilot quality improvement project was implemented to consistently use the electronic medical record paperless discharge system, already in place, to discharge lower acuity patients from the ED. Both overall LOS in minutes from door to discharge as well as disposition to discharge time were the outcome measures utilized for this project. IRB approval was obtained.
SETTING: ED of a community-based hospital that sees patients across their lifespan. This ED sees approximately 4500 patients monthly offering emergency services to patients of all ages.
PARTICIPANTS: Eligible participants included adult patients aged 18 years and older who presented to the ED with an Emergency Severity Index (ESI) acuity level of 3, 4, or 5. Inclusion criteria required that patients be established users of the MyOchsner patient portal, demonstrate proficiency in its use, and express willingness to participate in a paperless discharge process. Additionally, all participants were required to be English-speaking.
DO: Pre-Implementation- ED staff education
Educational sessions for ED staff were conducted over a two-week period preceding the implementation of the study. These sessions were offered at various times and on different days to enhance accessibility and promote broad staff participation. In total, 48 hours were dedicated to training ED personnel on the procedures, objectives, and workflow associated with the project, particularly the introduction of the electronic discharge process.
Staff were provided with standardized scripting to guide conversations with patients who expressed interest in electronic discharge. This scripting was intentionally general in nature, with the project lead available to address any detailed or patient-specific inquiries. Obtaining separate patient consent for participation was not required, as consent for care, including participation in quality improvement initiatives, was covered under the general consent signed by patients upon presentation to the ED.
Implementation:
The intervention group consisted of English-speaking adult patients, aged 18 years or older, who presented to the ED with an acuity level of 3, 4, or 5. Eligible participants demonstrated proficiency with the MyOchsner patient portal and expressed willingness to engage in the paperless discharge process. A total of 39 patients met these inclusion criteria and were subsequently assigned to the intervention group (n = 39), which utilized the paperless discharge protocol.
A total of 230 patients were included in the control group, all of whom underwent the standard discharge process (c = 230). These individuals were English-speaking and presented with acuity levels of 3, 4, or 5. They exhibited similar chief complaints and presented during the same operational hours as those in the intervention group. All control group patients were evaluated, treated, and discharged by alternate healthcare providers within the ED.
Recruitment
Intervention group- Chart reviews were conducted at the time of patient check-in to the ED to identify individuals who met the established inclusion criteria. Eligible patients were subsequently invited to participate in the project and, if they consented, were provided with information regarding the study and instructions on how to access their discharge materials electronically. In addition, retrospective chart reviews were performed at the conclusion of each shift to document relevant data for subsequent analysis. These activities were conducted over a cumulative total of 300 hours, corresponding to 25 12-hour shifts.
Control group- At the end of each shift, a retrospective chart review was conducted for a duration of one hour to identify adult, English-speaking patients who presented with chief complaints analogous to those of the intervention group and during equivalent operational hours. The review was limited to patients managed by providers not involved in the intervention and did not consider the patients’ level of proficiency with the MyOchsner patient portal. These activities were conducted over a cumulative total of 25 hours, corresponding to 25 12-hour shifts.
Advertising Material
Patient education- Laminated informational flyers will be strategically placed in triage and designated patient care areas within the ED to inform patients about the availability of the paperless discharge option. Patients who meet eligibility criteria for the study will also receive a printed handout containing detailed information and step-by-step instructions on how to access their electronic discharge materials through the MyOchsner patient portal following discharge.
Data Collection
Data for both the control and intervention groups were systematically collected and recorded in an encrypted Excel spreadsheet. For each participant in the control group, data included patient acuity, overall LOS, and time from disposition to discharge (measured in minutes), along with de-identified demographic information. Additionally, aggregate data on the number of control group patients were documented without individual identifiers, preserving only the overall LOS and disposition-to-discharge times. All data was securely stored on-site in an encrypted, password-protected Excel file accessible exclusively to the project lead.
RESULTS:
Results were analyzed using descriptive statistics.
Figure 1 presents a comparative analysis, in minutes, of the average overall LOS and disposition-todeparture times between patients who underwent paperless discharge and those who experienced the traditional discharge process. Implementation of the paperless discharge protocol was associated with a reduction in average overall LOS by 47 minutes and a decrease in average disposition-to-departure time by 9 minutes.
The implementation of the intervention resulted in a reduction of the average overall LOS by 47 minutes, decreasing from 234 minutes to 187 minutes. Additionally, the average time from disposition to physical departure was reduced by 9 minutes, from 46 minutes to 37 minutes.
IMPLICATIONS FOR PRACTICE:
Discharge delays contribute to ED overcrowding, which in turn can worsen patient outcomes. The AIM for this project was met. The average LOS was reduced by 20% and the disposition to depart time was reduced by 19.6% in the control group. These findings indicate that implementing a paperless discharge process within the ED may enhance patient throughput by reducing delays associated with traditional discharge procedures. These procedures often involve time-consuming administrative tasks such as documenting patient-specific discharge instructions, printing instructional materials, and generating hardcopy prescriptions.
The implementation of paperless discharge in this project demonstrated a reduction in both overall LOS and disposition-to-discharge time. By streamlining the discharge process through electronic means, valuable time is returned to healthcare providers, potentially allowing for increased attention to other patients, expedited patient turnover, and more rapid access to critical follow-up information. These improvements may contribute to decreased wait times and enhanced patient flow within the ED
Artful Aging: Impact of Creative Workshops on Wellbeing in Adults 55+
No full textLeadership and Learning in Organizations capstone projectThe Frist Art Museum offers hands-on artmaking workshops for adults aged 55 and older to promote well-being and lifelong learning through arts-based interventions. The museum has faced challenges in comprehensively measuring the program's impact on participants' physical and emotional health, cognitive function, and social engagement. Current quantitative surveys do not fully capture the deeper, long-term effects, and a lack of standardized evaluation tools within the creative aging field hinders benchmarking and data-driven improvements. This project employed a mixed-methods approach, using pre- and post-workshop surveys, mid-workshop open-ended surveys, and structured interviews with participants and staff to gather quantitative and qualitative data. The findings indicate a significant positive impact on participants' self-reported emotional and mental well-being, as well as their confidence in learning new skills. The percentage of participants reporting a perfect score for emotional health increased from 36% to 52%, and for mental health, it increased from 54% to 57%. While quantitative data showed no statistically significant change in overall physical health (p=0.3241), qualitative findings revealed indirect physical benefits, such as distraction from chronic pain. Additionally, the evaluation process itself was found to have opportunities for improvement, with feedback pointing to survey length, repetitiveness, and clarity issues. Based on these findings, it is recommended that the museum implement a holistic evaluation framework that integrates health, creative aging, and evaluation effectiveness perspectives to systematically measure multifaceted impacts. Recommendations also include refining and diversifying data collection methods, such as streamlining surveys and incorporating creative journaling or small group discussions to capture more nuanced impacts. Finally, the museum should integrate actionable components into workshops to encourage participants to apply their learning to broader community initiatives, thereby ensuring the program's long-term sustainability and demonstrating its value to stakeholders
Beyond the Mission: Understanding Belonging in Concorde’s Division
No full textLeadership and Learning in Organizations capstone projectConcorde’s Commercial Rocket Launch Division, also known as Nighthawk, is responsible for licensing and regulating commercial space activities to ensure safety and compliance with federal standards. Nighthawk is critical in regulating, licensing, and commercial space activities. Within Nighthawk, the Nexus division handles business operations, policy, and innovation and supports Nighthawk’s licensing and regulatory processes. As the commercial space industry expands, Nighthawk faces increasing complexity in its regulatory responsibilities. Employees, particularly in Nexus, report a diminished sense of belonging and misalignment with the organization’s mission to provide the safest, most efficient aerospace system in the world.
This study investigates:
1. How do employees' perceptions of their roles and responsibilities within Concorde’s commercial rocket launch division correlate with their sense of belonging to the organization?
2. What organizational factors significantly influence employees’ sense of belonging within the Concorde’s commercial rocket launch division?
3. What specific organizational strategies or practices can the Concorde’s commercial rocket launch division implement to strengthen employees’ sense of belonging?
This mixed-methods approach utilized survey data, leadership interviews, and insights from a strategic off-site to assess perceptions, organizational structures, and communication practices across the division. Findings revealed a significant disconnect between employees and the organization’s mission, particularly within the Nexus division, pointing to low levels of engagement, unclear role alignment, disconnect from the mission, and a lack of belonging within the workforce. Additional challenges include high workloads without clear staffing plans, weak communication from leadership, and low engagement metrics—only 29% of employees felt their talents were fully utilized. External scrutiny and rigid regulatory constraints compound internal frustrations, further weakening employee connection to the organization.
To address these issues, the study recommends four strategic actions:
(1) Strengthen leadership communication to align daily work with mission objectives
(2) Improve workforce development through structured engagement and talent utilization programs
(3) Foster a culture of inclusion and recognition to increase organizational belonging
(4) Streamline operational processes by involving employees in efficiency initiatives.
These recommendations aim to build a more connected, supported, and mission-driven workforce as Nighthawk continues to grow and are designed to cultivate a more engaged, resilient, and high-performing workforce capable of navigating the complexities and opportunities presented by the dynamic landscape of commercial space exploration
Empirical Essays on Labor Market Power and Work Quality
No full textEmployer monopsony power is increasingly viewed as an important feature of U.S. labor markets. This dissertation adds timely empirical evidence to ongoing debates about the effects of various sources of monopsony power, such as labor market concentration and noncompete agreements.
Chapter One analyzes the effects of labor market concentration on occupational safety, a principal dimension of working conditions. This chapter utilizes establishment-level workplace safety data and occupation- and industry-based measures of local labor market concentration. I also exploit changes in local labor market concentration due to merger and acquisition activity in a quasi-experimental difference-in-differences design. Overall, my results suggest that greater labor market concentration increases the health and safety risks that workers face on the job. I discuss the policy implications of these findings for workplace safety regulation and antitrust enforcement.
Chapter Two investigates the interaction between labor market concentration and noncompete agreements. This analysis is the first to connect high-quality concentration data to nationally representative U.S. labor market data that includes individual noncompete agreement status. I find that noncompetes are marginally more common in competitive labor markets, though there are still meaningful rates of noncompetes in concentrated markets. Moreover, the additional compensation that workers receive for noncompete agreements is substantially smaller in concentrated markets. These wage results are robust across several different demographic subsamples. The modulating effect of labor market concentration on noncompete agreement outcomes has implications for efficient noncompete regulation.
Chapter Three explores a previously unquantified relationship between noncompete agreements and union membership. Despite their long-run institutional decline, unions remain an important determinant of work quality. My empirical strategy primarily leverages a 2008 Oregon law that restricted the enforcement of noncompete agreements against hourly workers. I find the probability of union membership increases when noncompetes become more difficult to enforce
Building Pathways for Afghan Refugee in Massachusetts
No full textLeadership and Learning in Organizations capstone projectThe 2021 United States military withdrawal from Afghanistan led to the rapid evacuation of over 124,000 Afghan nationals, revealing deep structural failures in the American refugee resettlement system. In response, the Massachusetts Afghan Alliance—founded by veterans and Afghan refugees—emerged to fill critical service gaps for newly arrived parolees across Massachusetts. This capstone investigates how grassroots, crisis-born nonprofit can transition into a sustainable, systems-oriented institution capable of supporting long-term refugee integration. Using a hybrid participatory action research (PAR) and qualitative case study methodology, the project draws from 23 in-depth interviews, field observations, and cross-sector policy analysis. Findings identify three structural barriers to Afghan refugee integration: housing insecurity, credential non-recognition, and the absence of culturally responsive mental health services. Internally, the organization faces challenges in volunteer management, governance clarity, and financial sustainability. This study introduces the original Business Strategy House Model, a conceptual framework that links refugee-centered program design to strategic institutional development. It is guided by four theoretical frameworks: refugee integration theory (Ager & Strang), institutional legitimacy theory (Suchman), the competing values framework (Cameron & Quinn), and collaborative governance theory (Ansell & Gash). The project offers targeted, evidence-informed recommendations: implement a comprehensive housing navigation initiative; create professional bridging pathways for Afghan credential holders; embed trauma-informed, culturally anchored mental health services; formalize volunteer onboarding and retention systems; and establish cross-sector governance boards. These interventions provide a replicable model for transforming grassroots refugee organizations into resilient, ethically grounded institutions that meet long-term integration needs
Magnetic Capsule Robot for Tissue Elasticity Sensing and Tissue Biopsy
No full textMonitoring the mechanical properties of soft biological tissues in the gastrointestinal (GI) tract offers a vital route for the early detection of conditions such as intestinal fibrosis, colorectal cancer, and other GI tract diseases. Existing approaches designed to evaluate tissue stiffness often suffer from insufficient accuracy and can impose patient discomfort or the requirement of risky anesthesia for flexible endoscopes or implantable devices. On the other hand, tissue biopsy is essential for diagnosing inflammatory bowel disease (IBD), ulcers and cancer. Existing methods either need anesthesia when using endoscopes or exhibit high risks of obstruction when using capsule robots with needles due to lack of sensory feedback. These limitations underscore the need for advanced minimally invasive capsule devices that can measure tissue elasticity and perform safe and precise biopsy in the hard-to-reach areas such as the small intestine and upper colon. To address these challenges, this thesis reports swallowable capsule devices for palpation-based tissue elasticity sensing and sensor-integrated tissue biopsy. The first device features a remotely actuated palpation mechanism that utilizes an external magnetic field, which relies on a flexible cantilever beam to gently press against soft tissues, with stress and strain recorded by an onboard magnetic sensor and a strain gauge. Real-time communication is enabled by a battery-powered Bluetooth Low Energy (BLE) module, allowing the device to operate autonomously. Additionally, the second capsule device integrates both a sensing unit and a specialized biopsy needle equipped with integrated flexible sensors, thus enabling controlled tissue sampling based on penetration force and displacement feedback. To ensure accurate positioning, a sensor array is deployed for tracking the capsule’s location and orientation during the biopsy procedure. Overall, the magnetically controlled capsule devices show potential for minimally invasive targeted diagnosis functions, to allow earlier interventions for various GI disorders