Digital Commons Network^™

Pattern Dynamics And Stochasticity Of Brain Rhythms And Spike Trains In A Tauopathy Mouse Model Of Alzheimer’S Disease, Clarissa M. Hoffman

Dissertations and Theses (Open Access)

Systems neuroscience posits that every aspect of perceived physical reality, every aspect of animal and human behavior, and every cognitive phenomenon emerges from patterns of neuronal activity. While most researchers embrace this idea, there are major difficulties in describing and analyzing these complex neuronal dynamics—spike flows produced by cells ensembles, synchronized extracellular field oscillations, and other patterns—which limits our understanding of how the activity of individual neurons and the whole-animal cognition and behavior might be connected. In particular, we lack the approaches and even the semantics for connecting the individual cell outputs and the integrated results of their activity. Current …

An Integrated Framework For Early Detection And Transmissibility Assessment Of Emerging Variants In Wastewater, Xingwen Chen, Tin Phan, Wei Lin Lee, Katie Clark, Steven F Rhode, Samantha Brozak, Bruce Pell, Tsultrim Palden, Mats Leifels, Anna Gitter, Yang Kuang, Stefan Wuertz, Janelle Thompson, Kristina D Mena, Eric J Alm, Fuqing Wu

Faculty, Staff and Student Publications

Tracking the emergence of new viral variants is critical for epidemic preparedness, but remains challenging because variants typically circulate at low prevalence during the early phase of outbreaks. Here, we present an integrated framework that combines sensitive variant detection in wastewater with quantitative assessment of transmissibility through dynamic epidemic modeling. Using the SARS-CoV-2 Omicron variant as a proof of concept, we developed a novel nested allele-specific RT-qPCR assay (NAS-PCR) that achieved a thousand-fold increase in sensitivity compared with allele-specific RT-qPCR (limit of detection: 0.5 copies/μl). NAS-PCR detected Omicron in wastewater samples from the Greater Boston area starting in September 2021, …

Understanding Vaccine Hesitancy In Veterinary Medicine: A Review Of Client Attitudes, Grace Moore

Undergraduate Honors Capstone Projects

Uncertainty toward vaccination, long recognized as a public health concern in human medicine, is increasingly recognized within veterinary contexts, posing risks to both animal and community health. This literature review examines the development, causes, and implications of reduced vaccine confidence in veterinary medicine, with emphasis on small animal and some large animal practices. The review combines historical and current research to explore how vaccination perceptions have evolved among veterinarians and clients, and how factors such as the COVID-19 pandemic have shaped current attitudes.

The literature highlights recurring themes surrounding vaccine reluctance in veterinary settings. Client perceptions of safety, efficacy, and …

Towards Dementia-Inclusive Digital Text-Based Health Information: A Multi-Method Investigation Of Cognitive And Affective Accessibility, Margi Engineer

All Dissertations

This dissertation examines the accessibility, readability, emotional tone, and trustworthiness of digital, text‑based dementia information and investigates how older adults with and without dementia cognitively and affectively engage with such content. It further explores the potential of generative AI to improve dementia information delivery through the development of a domain‑specific retrieval‑augmented generation (RAG) large language model (LLM) chatbot designed to deliver accessible, stigma‑free information. The dissertation comprises four studies using complementary quantitative and qualitative methods. Study I conducts a large‑scale content analysis of 300 medical articles, 35 websites, and 50 blogs, applying readability metrics, LIWC‑based linguistic and sentiment analysis, and …

Abnormal Trafficking And Processing Of Multiple Matrix Metalloproteinases Drive Cartilage Defects In Congenital Disorders Of Glycosylation, Chia-Lun Wu

All Dissertations

Congenital Disorders of Glycosylation (CDG) are rare metabolic diseases caused by defects in glycosylation. Despite identification of over 200 CDG types, the mechanisms linking glycosylation defects to diverse clinical phenotypes remain unclear. This dissertation uses zebrafish models of PMM2-CDG and STT3-CDG to redefine CDG pathogenesis, shifting from a simple glycan deficiency model to one involving disrupted cellular spatial organization.

We identify a protease-dependent pathway underlying craniofacial cartilage defects. Specifically, defective proteolytic processing of N-cadherin, a key adhesion molecule in chondrogenesis, is a central driver of pathology. We further uncover an unconventional trafficking mechanism in which ER stress and altered secretory …

Caregiver Self-Reflection: Does It Matter? A Study Of The Relationship Between Caregiver Self-Reflection And Participation In Home Programs In Outpatient Pediatric Physical Therapy Settings, Andrea Myane

Graduate Theses and Dissertations

Despite evidence that caregiver coaching can improve patient outcomes and caregiver participation, little information exists on the effects of its individual components. Additionally, previous research has highlighted the importance of home programs in improving pediatric physical therapy outcomes. The aim of this study is to explore the role that caregiver self-reflection, a component of caregiver coaching, plays in facilitating outcomes in the pediatric physical therapy outpatient setting. Caregivers will be asked to complete a series of self-reflection questions based on Gibbs’ Reflective Cycle, while also recording the number of minutes they spend facilitating a prescribed home program. All study participants …

Developmental Assets And Risk-Related Restraint And Resistance Orientations Among Emerging Adult College Students: Examining Protective Associations, Summer N. Beck

Graduate Theses and Dissertations

Abstract Background: Although developmental assets are well established as protective factors during childhood and adolescence, less is known about their role during emerging adulthood, a period when the prevalence of several types of risk behaviors peak. For the U.S. college student, campus can provide ideal conditions for supporting the extended transition to adulthood. However, that same environment may increase exposure to health risk behaviors. This study examined associations between developmental assets and the risk-related restraint and resistance orientations involving sexual activity, alcohol, and illicit drugs among emerging adult college students. Methods: A cross-sectional correlational design was employed with a sample …

Investigating The Influence Of Dietary Phytogenics And Postbiotics On Horizontal Transmission Of Histomonas Meleagridis In Commercial Turkey Poult Hens, Diego Fernando Cortes Velez

Graduate Theses and Dissertations

Histomonas meleagridis is a parabasalid protozoan and the causative agent of histomonosis, or blackhead disease, in turkeys. Withdrawal of the last remaining in-feed arsenical from the market in 2015 led to the re-emergence of the disease. As a result, there is a need to investigate alternatives, such as dietary inclusion of postbiotic and phytogenic compounds, to reduce H. meleagridis transmission and disease severity in commercial turkey flocks. The purpose of this project was to evaluate the influence of dietary inclusion of three different combinations of postbiotic and phytogenic compounds on H. meleagridis transmission in turkey poult hens. A thesis introduction …

Addressing Nonignorable Missing Data And Heterogeneity In Prognostic Biomarker Assessment, Xinran Huang, Ruosha Li, Jing Ning, For The Alzheimer's Disease Neuroimaging Initiative

Faculty, Staff and Student Publications

Covariate-specific and time-dependent area-under-curve (AUC) is often used to evaluate the discriminative performance of biomarkers with time-to-event outcomes, particularly when certain covariates influence biomarkers' accuracy. In biomarker research, despite extensive efforts, missing data remain unavoidable, with nonignorable missingness posing significant challenges. This article focuses on estimating the impact of covariates on time-dependent AUC in the presence of nonignorable missing biomarkers. Assuming a parametric model on the missing probability, we leverage instrumental variables to address the identifiable issue and estimate the unknown parameters. We integrate the inverse probability weighting approach into the score equation of a pseudo partial likelihood for estimation …

Understanding The Role Of Toxs As A Bile Sensing Component Of The Toxrs Virulence Regulatory System In Vibrio Spp., Minje Kim

Dartmouth College Ph.D Dissertations

Pathogenic Vibrio bacteria, such as V. cholerae and V. parahaemolyticus, colonize in the human small intestine to cause severe gastrointestinal disease. During the infection, these bacteria encounter bile salts, antimicrobial cholesterol metabolites secreted into the intestine. Pathogenic Vibrio species have evolved to utilize bile salts as signals to regulate virulence. The signaling depends in part on ToxRS, a conserved co-component transmembrane transcription regulator. ToxRS consists of the transcription factor ToxR and its membrane-tethered binding partner ToxS. ToxS is required for ToxR stability and full transcriptional activity. Although bile salts are known to influence ToxRS-dependent virulence gene expression, the molecular …

Qualitative Beta-2-Adrenoceptor Signaling In The Regulation Of Human Airway Epithelia Mucin And Cytokine Production, Fred Graumuller, Diana Cervantes, Tung O. Chan, Niccolette Schaunaman, Dominic R. Villalba, Burton F. Dickey, Julia K. L. Walker, Hong Wei Chu, Raymond B. Penn

Division of Pulmonary, Allergy, and Critical Care Medicine Faculty Papers

BACKGROUND: Numerous in vivo studies have demonstrated beta-2-adrenoceptor (β2AR) -agonism as permissive in the development of allergic lung inflammation, and have implicated the arrestin-dependent signaling arm of the β2AR in mediating this effect. However, the specific cell type(s) mediating β2AR regulation of allergic lung inflammation remain unestablished.

METHODS: To explore the potential contribution of airway epithelia in this phenomenon, we compared the ability of ractopamine (RP), recently identified as a Gs-biased beta-agonist, to that of the unbiased/balanced beta-agonist albuterol (ALB), on IL-13-stimulated mucin and cytokine production in human airway epithelia cultures in air-liquid interface (HAE).

RESULTS: ALB, which activates both …

Gestational Diabetes And Social Determinants Of Health In Black Women, Darianne Greenwood

Capstone Experience: Master of Public Health

Gestational Diabetes Mellitus (GDM) poses significant health risks, specifically increasing the risk of developing Type 2 Diabetes post-delivery, as well as increasing the risk of adverse neonatal and maternal outcomes. Black women, in particular, experience disproportionately higher rates of GDM incidence, severity, and complications in comparison to White women. Biological factors alone do not account for these disparities, necessitating a deeper examination into how systemic factors, particularly the social environment, influence these inequitable health outcomes. The purpose of this comprehensive literature review is to answer the question: “How do the Social Determinants of Health (SDoH), such as residential segregation, food …

In-Vitro Testing Of Light Wavelength To Detect Clots In Neonatal Extracorporeal Membrane Oxygenation Circuitry, Amanda Holmes

Dissertations and Theses (Open Access)

Background: Neonates requiring extracorporeal membrane oxygenation (ECMO) are at high risk for thrombotic complications, which contribute substantially to morbidity and mortality. Current circuit surveillance methods rely on intermittent visual inspection and indirect laboratory markers, both of which often detect thrombosis only after clinically significant progression. Optical approaches offer a non-invasive alternative for earlier clot visualization, yet the influence of illumination wavelength on detection performance under realistic ECMO conditions remains incompletely characterized.

Methods: This study evaluated wavelength-dependent clot detection performance in a controlled in-vitro neonatal ECMO circuit model using a portable imaging prototype designed to emulate bedside workflow. Twelve independent ECMO …

Factors Associated With Postpartum Depression Symptoms Following Antepartum Hospitalization, Alison N Goulding, Daniel Palacios, Sukru Aras, Hu Chen, Sasidhar Pasupuleti, Marika Toscano, Nicole Cirino, Israel C Christie, Zhandong Liu, Emily S Miller, Terri L Fletcher

Duncan NRI Faculty and Staff Publications

Background: Hospitalized antepartum patients are at increased risk for postpartum depression (PPD). Developing approaches to identify those at highest risk for PPD would enable timely and targeted intervention.

Objective: We aimed to identify factors associated with the development of PPD symptoms in hospitalized antepartum patients and to assess their predictive utility.

Study design: This retrospective cohort study included pregnant individuals hospitalized in a regional referral center due to medical or obstetric complications between 2012 and 2025. Data were extracted from the electronic health record, including demographics, medical and obstetric history, hospitalization characteristics, and postpartum Edinburgh Postnatal Depression Scale (EPDS) scores …

Low-Abundance And Fragmentary Helicobacter Pylori Dna Detected In Phenotypically Negative Gastric Biopsies Using Targeted Sequencing, Fabien Mbaya-Tshibangu, Alain Cimuanga-Mukanya, Evariste Tshibangu-Kabamba, Nadine Kayiba-Kalenda, Tressy Kalenga-Ngomba, Patrick Ngoma-Kisoko, Gunturu Revathi, Junko Akada, Benoît Mbiya-Mukinayi, Augustin Tshibaka Kabongo

Pathology, East Africa

Accurate detection and monitoring of antimicrobial resistance (AMR) in Helicobacter pylori mainly rely on phenotypic methods and culture, which can sometimes fail when bacterial load is low or after recent treatment. We investigated whether gastric biopsies classified as H. pylori-negative by standard diagnostic techniques still contain detectable bacterial DNA, including regions linked to AMR, and assessed whether selected DNA fragments can mediate allelic exchange in vitro. Gastric biopsies from 46 dyspeptic patients in the Democratic Republic of the Congo (including 23 phenotypically positive and 23 phenotypically negative individuals) were analyzed using long-read amplicon sequencing of seven resistance-associated loci, selective whole-genome …

2-Aminobutyrate Mediates The Impact Of Air Pollution On Blood Biomarkers Of Alzheimer’S Disease, Anum Saeed, Chris Mckennan, Jane E Clougherty, Peidi Zhou, Sheila Tripathy, Ellen J Kinnee, Jiaxuan Duan, Kevin Kip, Xuemei Zeng, Victor Villemagne, Tharick Pascoal, Mark Mapstone, Eric A Whitsel, Oscar I Lopez, Christie Ballantyne, Thomas K Karikari, Bing Yu, Steven Reis, Annie Cohen

Faculty, Staff and Students Publications

Introduction: We examined the impact of mid-life metabolites on late-life Alzheimer's disease (AD) plasma biomarkers and whether these metabolites mediate air pollution effects.

Methods: In the Heart Strategies Concentrating on Risk Evaluation (Heart SCORE) cohort, we applied high-dimensional regression and meditation models, adjusting for observed and latent confounders, with replication in the Atherosclerosis Risk in Communities (ARIC) study. Exposures included mid-life fine particulate matter (PM2.5), black carbon, metals, and metabolites. Outcomes were: late-life plasma p-tau(181, 217, and 231) and amyloid beta 42/40 (Simoa assays).

Results: In the Heart SCORE study, seven lipid- and amnio acid-pathway metabolites measured in mid-life were …

Fructose: Metabolic Signal And Modern Hazard, Richard J Johnson, Miguel A Lanaspa, Dean R Tolan, Marcus D Goncalves, Samir Softic, Kimber L Stanhope, Laura G Sánchez-Lozada, Mark A Herman, Joshua D Rabinowitz

Faculty, Staff and Students Publications

There is much interest in the role of sweeteners such as table sugar (sucrose) and high-fructose corn syrup in obesity and metabolic disease. Both sweeteners consist of glucose and fructose, two six-carbon isomeric sugars. Whereas glucose ingestion may promote obesity through its effects to stimulate insulin secretion, fructose has unique metabolic effects that promote triglyceride synthesis and fat accumulation. These effects arise from fructose's well-known role as a signal of metabolic plenty. Under modern conditions of overnutrition, chronic excess fructose drives features of metabolic syndrome. Emerging evidence further links fructose to cancer and dementia. Here we review the biochemical, molecular …

Antibiotics Aren’T Enough, Andrew R Dinardo, Christoph Lange

Faculty, Staff and Students Publications

No abstract provided.

Race To Mitigate Aortic Dissection: Exercise, Pde5a, And The Dissecting Aorta, Siddharth K Prakash

Faculty, Staff and Student Publications

No abstract provided.

Quantitative Muscle Magnetic Resonance Imaging Demonstrates Resolution Of Muscle Edema In Refractory Dermatomyositis: A Post Hoc Analysis Of A Proof-Of-Concept Clinical Trial Of Tofacitinib, Mona Dabiri, Anshula Nallapati, Marwin Groener, Patrick Debs, Jemima Albayda, Eleni Tiniakou, Lisa Christopher-Stine, Laura Fayad, Julie J Paik

Faculty, Staff and Student Publications

Objective: To evaluate changes in muscle edema using short-tau inversion recovery (STIR) imaging and quantitative diffusion-weighted imaging (DWI) with apparent diffusion coefficient (ADC) mapping in patients with refractory dermatomyositis (DM) treated with tofacitinib.

Methods: This post hoc imaging analysis included patients from a 12-week, open-label trial of tofacitinib 11 mg daily in refractory DM. Bilateral thigh magnetic resonance imaging was obtained at baseline and week 12 using standardized STIR, T1-weighted, and DWI sequences. Muscle edema (ME) and fascial edema were assessed qualitatively on STIR imaging. ADC values were measured in muscles demonstrating baseline STIR hyperintensity using three nonoverlapping regions of …

Severe, Non-Apneic Respiratory Dysfunction And Hypoxia Following Generalized Convulsive Seizures, Haley E Pysick, Rup K Sainju, Roshni Nair, Deidre N Dragon, Eduardo Bravo, Laura Vilella, Xiaojin Li, Samden D Lhatoo, George B Richerson, Brian K Gehlbach

Faculty, Staff and Student Publications

Objective: Sudden unexpected death in epilepsy (SUDEP) is a devastating consequence of some generalized convulsive seizures (GCS). Recent work has focused on seizure related apnea as a biomarker of SUDEP risk, frequently without characterizing the adequacy of non-apneic ventilation or identifying other dysfunctional breathing patterns. We hypothesized that GCS frequently induce immediate, severe, non-apneic respiratory dysfunction that can induce critical hypoxia and bradycardia and sought to characterize breathing patterns after GCS.

Methods: Adult patients admitted to an epilepsy monitoring unit were studied. The effects of GCS on breathing and heart rate were analyzed using nasal pressure transducers, chest and abdominal …

Neurointerventional Advances In 2025, Amol Mehta, Sunil A Sheth, Ashutosh P Jadhav

Faculty, Staff and Student Publications

No abstract provided.

Optimized Ultrasound Imaging Of Phase-Change Nanodroplets, Charles R Dyall, Dmitry Nevozhay, Andy Liu, Trevor M Mitcham, George J Lu, Konstantin V Sokolov, Richard R Bouchard

Faculty, Staff and Student Publications

Phase-change nanodroplets (PCNDs) continue to generate significant research interest due to their potential to extravasate into tissue, to be targeted for molecular imaging and drug delivery, and to undergo an induced phase-change to "activated" microbubbles (MBs) for ultrasound (US) imaging. To accurately quantify molecular markers, however, one assumes a consistent proportion of PCNDs in a region of interest (ROI) are stably activated and imaged. Herein we present a framework for developing a diagnostic sequence that is optimized for PCND activation uniformity, contrast, and acquisition time. To develop this framework, activation was examined at three scales of increasing complexity: single, adjacent, …

Multidisciplinary Approach To Complex Lower Extremity Limb Salvage In Pyogenic Arthritis, Pyoderma Gangrenosum, And Acne (Papa) Syndrome: A Case Report, Michael M Talanker, Anthony V Basta, Tien Do, Robert Tung, Addison Allen, Morgan Martin, Bryan L Ruygrok, Patrick J Kellam, Jeffrey G Trost, Mohin A Bhadkamkar

Faculty, Staff and Student Publications

Limb salvage using free tissue transfer in patients with rare autoinflammatory syndromes is poorly described, and the safety of microvascular reconstruction in this population remains uncertain. Hereditary pyogenic arthritis, pyoderma gangrenosum, and acne (PAPA) syndrome is characterized by dysregulated inflammation, pathergy, and impaired wound healing, raising concern for flap compromise and postoperative complications. We report a rare case of lower extremity free tissue transfer in a patient with PAPA syndrome. A 66-year-old woman with rheumatoid arthritis and PAPA syndrome presented with rapid wound breakdown, violaceous ulceration, exposed hardware, and periprosthetic joint infection following left total knee arthroplasty (TKA). Examination revealed …

Potential Impact Of Parasites In The Transmission Of Chronic Wasting Disease, Paulina Soto, Rodrigo Morales

Faculty, Staff and Student Publications

No abstract provided.

Long Covid Persistence And Surveillance Gaps Across 58 Us Hospitals, Jiazi Tian, Alaleh Azhir, Matthew Decaro, Ngan Chau, Jonas Hügel, Michele Morris, Jingya Cheng, Pedram Fard, Ingrid V Bassett, Douglas S Bell, Elmer V Bernstam, Shyam Visweswaran, Jeffrey G Klann, Shawn N Murphy, Hossein Estiri

Faculty, Staff and Student Publications

Importance: Surveillance of postacute sequelae of SARS-CoV-2 infection (PASC) depends on diagnostic coding systems that capture fewer than one-half of affected individuals, rendering millions invisible to health systems and policymakers.

Objective: To quantify the gap between true PASC burden and diagnostic code-based estimates, determine the proportion representing chronic disease, and characterize organ system heterogeneity and temporal trends across diverse populations.

Design, setting, and participants: This retrospective cohort study used electronic health record data from 58 hospitals and affiliated clinics in 4 US regions, from 2017 to 2025. Adults (aged ≥18 years) with laboratory-confirmed SARS-CoV-2 infection or a COVID-19 diagnosis code …

Ucva Ontology: Standardizing Local Context Factors To Support The Analysis Of Unwarranted Clinical Variation, Apollo Mcowiti, Xubing Hao, Rebecca Z Lin, Laila Rasmy-Bekhet, Cui Tao, Susan Fenton

Faculty, Staff and Student Publications

Objectives: Unwarranted clinical variation (UCV), defined as care provided to a patient that is not proportional to the patient's needs, clinical characteristics, or preferences, results in negative patient outcomes. UCV detection is performed to compare healthcare outcomes across regions or organizations and reduce UCV incidences. However, the lack of standardized UCV concepts and the local context factors hinder the interoperability of UCV analyses between organizations. Currently, UCV analysis relies on centralized analysis, posing challenges due to the proprietary nature of an organization's healthcare and operational data. Standardizing analysis factors enables interoperable analyses by establishing a common context between organizations. This …

Growth Hormone Pathway As A Prognostic And Therapeutic Biomarker In Patients With Unresectable Hepatocellular Carcinoma Treated With Radiation Therapy, Joe R Eid, Safa Kaseb, Lianchun Xiao, Ryan Sun, Mahesh Kumar Kannan, Manal Hassan, Asif Rashid, Hop S Tran Cao, Hesham M Amin, Eugene J Koay

Faculty, Staff and Student Publications

Purpose: Radiation therapy (RT) has emerged as an effective local therapy option for patients with unresectable hepatocellular carcinoma (HCC) and is associated with improved overall survival (OS). However, some patients still have poor outcomes after RT, and biomarkers are needed to stratify prognostic groups. High circulating growth hormone (GH) levels promote HCC proliferation and survival and are associated with aggressive disease. In this study, we evaluated whether pretreatment GH levels are associated with OS and progression-free survival (PFS) in patients who underwent RT for unresectable HCC.

Methods and materials: Patients undergoing RT for HCC during 2017-2023 were identified from a …

Computational Modeling Meets 3d Bioprinting: Emerging Synergies In Cardiovascular Disease Modeling, Tanmay Mukherjee, Mehdi Salar Amoli, Sarah Rezapourdamanab, Lama Rita El Shammas, Martin L Tomov, Emilio A Mendiola, Vahid Serpooshan, Reza Avazmohammadi

Faculty, Staff and Student Publications

Cardiovascular diseases (CVDs) remain the leading cause of death worldwide, underscoring the need for improved strategies in diagnosis, treatment, and disease modeling. Traditional in vitro models often fall short in replicating human CV physiology, prompting efforts to advance cardiac tissue engineering and computational modeling. Among these, three-dimensional (3D) bioprinting has emerged as a transformative tool, enabling the creation of biomimetic CV constructs that more faithfully replicate native tissue structure and function. However, challenges persist in achieving appropriate mechanical properties and long-term performance of engineered CV constructs. Computational modeling offers powerful solutions to assist with these challenges, providing predictive insights into …

Estrogen As A Therapeutic Agent: Targeting Endotheliopathy And Coagulopathy In Trauma, Niruktha Raghavan, Mira Patel, Bryan A Cotton, Julia Coleman, Donald Jenkins

Faculty, Staff and Student Publications

Background: Traumatic injury remains a leading cause of death, often due to uncontrolled hemorrhage and trauma-induced coagulopathy (TIC). TIC is critically triggered by the endotheliopathy of trauma, involving endothelial cell injury and glycocalyx degradation. Despite conventional advances, the stable casualty rate underscores the urgent need for new precision resuscitation strategies that acknowledge factors like biological sex.

Design: The central hypothesis is that estrogen confers a survival advantage in hormonally active females through a dual action: endothelial cell stabilization (halting glycocalyx shedding) and its inherent procoagulant effect. The analysis assesses the therapeutic potential of both exogenous estrogen and female-derived blood products …