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Analytical Studies of Black Hole Systems
Get PDFThis work includes a series of analytical projects aimed at providing accurate initial data parameters for full Numerical Relativity evolutions of binary black holes (BBH), allow the evolution of multiple black hole systems, and the interpretation and modeling of high- energy collision of black holes. We first describe how to obtain accurate initial data for the evolution of BBH by extending the determination of quasi-circular orbital parameters described in [1] to 3.5PN, and by incorporating the small mass ratio limit by explicitly including the Schwarzschild and Kerr limits [2]. We then focus on eccentric binary black hole systems, developing a new estimation method for their eccentricity based on post-Newtonian (PN) theory, introducing the fractional parameter f to quantify the change of tangential momenta relative to the corresponding quasi-circular one at the initial turning points of the orbit. In the third project, we study initial data for triple black hole systems in a hierarchical system of three black holes, as one of the main candidates to explain non negligible residual eccentricity in late stages of the inspiral. Specifically, we extend the method described in [3, 4] to second order to solve the Hamiltonian constraint equation of the transverse and conformally flat initial data problem in General Relativity. This method is then applied to compute approximate initial data for the evolution of triple black hole systems [5]. Lastly, in the fourth project [6], we employ the Zero Frequency Limit (ZFL) expansion to semi-analytically model the energy and angular momentum radiated during the merger of high-energy-collisions of binary black boles as a function of their impact parameter and initial relativistic momenta. We thus stress the relevance of combining analytic with full numerical methods to study the dynamics of black holes in astrophysical scenarios and beyond
CRISPR-dCAS9 genomic engineering for boosting the therapeutic potential of Extracellular Vesicles
Get PDFDegenerative disc disease is a major contributor to low back pain, characterized by inflammation of the intervertebral disc (IVD), degradation of the extracellular matrix, loss of hydration, and cell death. Current therapies fail to address these underlying mechanisms, underscoring the need for regenerative strategies. Mesenchymal stem cells (MSCs) exhibit immunomodulatory and regenerative potential, but their efficacy is hampered by the harsh microenvironment of the degenerated IVD. Acellular MSC-derived extracellular vesicles (EVs) have shown therapeutic potential and offer a promising alternative for IVD regeneration. Here, we explore CRISPR-dCas9 mediated activation of TSG6 and STEAP3 to boost the therapeutic potency and biogenesis of MSC-derived EVs, respectively. This project seeks to determine the feasibility of using CRISPR-dCas9 activation to enhance the regenerative capacity of MSC-EVs in an IVD (Aim 1) and a macrophage treatment model (Aim 2), and to determine the feasibility of using CRISPR multiplexing for advancing EV therapy (Aim 3). CRISPRa-mediated activation of TSG-6 in MSCs produced EVs that exerted anti-inflammatory effects on both human IVD cells and macrophages, partially exceeding those of control MSCs. Small RNA-seq and proteomic analyses of these EVs confirmed enrichment of anti-inflammatory microRNAs and proteins. Proof-of-concept multiplexed activation of TSG-6 and STEAP3 in pluripotent stem cells was successfully achieved, yielding a modest increase in EV production upon differentiation into MSCs. These findings validate CRISPR-dCas9 activation as a robust strategy to improve the therapeutic efficacy and production of MSC-derived EVs, and they establish the feasibility of gene-multiplexing approaches for future regenerative-medicine applications
Dyadic and multiparty turn-taking in two deaf preschool classrooms
Get PDFConversational turn-taking skills are needed to succeed in most conversational interactions. Timing of turn-taking is crucial for young deaf signers, who need early, accessible, and consistent input in a signed and/or spoken language. For deaf children who acquire a language in either modality, they must acquire appropriate turn-taking skills. Without these abilities, children may miss critical language input, and in a cascading effect–they may miss opportunities both for input (and thus new knowledge) and expressive language. In addition to documenting deaf children’s turn-taking skills across development, it is important to also document timing data for further understanding of cognitive language processing in a signed modality. In obtaining this observational timing and frequency data on turn-taking, we can understand how language processing differs in a gestural-visual rather than a spoken modality. This thesis reports American Sign Language (ASL) turn-taking behaviors in deaf children aged three-to-four years old in two preschool classrooms at a deaf residential school, where deaf teachers take on roles as social and language agents in deaf children’s acquisition of bimodal-bilingual ASL-English turn- taking skills. Specifically, we see the impacts of interaction type (Dyadic, one-on-one conversation compared to Multiparty conversation) and the presence of peers versus teachers in conversation
Network and Tree-based Approaches to Data-Driven Modeling of Complex Climate Systems
Get PDFThe guiding thread throughout this thesis work is data-driven modeling of Earth\u27s climate. We investigate a variety of settings within the field of complex climate systems, such as gridded, high-resolution reanalysis data, lower-resolution climate indices, and incomplete paleoclimate records with missing values. We begin with reanalysis data of high spatial and temporal resolution, and use climate network analysis to uncover hidden trends in the data in regards to the Amazon rainforest and its changing role in the global climate system. We introduce a novel formulation of k-nearest neighbors climate networks to study changing trends at a local level, and apply graph diffusion and random walks to study the Amazon\u27s changing connectivity structure. We then shift focus to making forecasts of the future state of Earth\u27s climate rather than studying historical data, and introduce TreeDOX: a regression-tree-based approach to chaotic time series forecasting. TreeDOX features a variety of advantages, such as resilience to low training volume and automated hyperparameter tuning using statistical tests performed on the supplied training data. We use a variety of toy models to perform benchmarking of TreeDOX in comparison to state-of-the-art chaotic time series forecasting methods, and also demonstrate the efficacy of TreeDOX in a real-world setting by forecasting the Southern Oscillation Index (SOI)---a time series with strong ties to several critical climate phenomena. Next, we investigate empirical mode decomposition (EMD)---a data-driven method for decomposing nonlinear, nonstationary time series into a finite basis of orthogonal, stationary modes---as a method of automated TreeDOX preprocessing. We perform an extensive numerical experiment featuring 26 climate time series (including SOI) to establish that EMD-TreeDOX does forecast climate phenomena with higher accuracy than TreeDOX. Lastly, we adapt TreeDOX (and EMD-TreeDOX) to perform imputation of missing values (i.e., gap-filling) in time series. Missing values are common in many fields in the climate sciences (especially those that require remote sensing), but we wish to test TreeDOX gap-filling in perhaps the most challenging of settings: paleoclimate time series. Paleoclimate proxy records play an important role in the understanding of the current and future climate by establishing a baseline of extremely low-frequency trends in climate dynamics. Here, we use 14 real-world paleoclimatic time series that come in the form of speleothem (stalactite and stalagmite) oxygen isotope records from Asian caves, which have previously been shown to exhibit connections to Asian monsoon intensity. While leaving room for future improvement, we find TreeDOX and EMD-TreeDOX to be promising data-driven gap-filling techniques capable of using nonlinear, nonstationary dynamics to inform the imputation of missing values
Ambient Environment Effect on Color Perception
Get PDFThe ambient environment—including both background and surround conditions—is a critical factor influencing color perception. It affects not only how we perceive colors but also how we interpret complex visual scenes, impacting both sensory processing and cognitive interpretation. This thesis focuses on three major perceptual phenomena: simultaneous contrast, mixed chromatic adaptation, and color preference. First, the effects of simultaneous contrast on hue, chroma, and lightness in traditional displays were explored. This study was extended to a dual-display augmented reality (AR) environment that introduces layered perception. An extension to the CIECAM16 color appearance model is proposed to incorporate this effect. Second, the impact of a mixed lighting environment created by variations in the luminance and chromaticity of the background and surround influence chromatic adaptation mechanisms was examined. Based on the findings, modeling frameworks to better account for these effects are proposed. And third, image and video preference under different ambient environments were explored, revealing that ambient conditions, content, observer characteristics, and display all significantly influence visual preference. Together, these studies highlight the importance of ambient environmental factors in color perception, emphasizing their impact across appearance, adaptation, and aesthetic judgment
Haunted Echoes
Get PDFHaunted Echoes explores the narrative and emotional possibilities of interactive digital fiction by creating a room-based haunted experience. By placing the users within a haunted manor the project encourages emotional discovery through narrative exploration. As a room-based exploratory experience, users get to navigate a dollhouse-style 3D interface, interacting with objects to reveal layered micro-stories and uncover the manor’s haunted past. The experience turns spatial exploration into emotional discovery, drawing inspiration from immersive theater, point-and-click adventures, and environmental storytelling in video games. The thesis examines the intersection and overlap of interactive storytelling, visual communication, and emotional immersion, integrating 3D modeling (Blender/Cinema 4D) and prototyping tools (Figma/Adobe After Effects) to create narrative depth and compelling user agency. Haunted Echoes contributes to the growing intersection of narrative design and digital environments by demonstrating how interactive form can deepen affective engagement
Future of Inclusive Education in the UAE: Supporting Learning Disabilities in Higher Education
No full textInclusive education is a critical component of higher education, ensuring that students with learning disabilities (LDs) receive equitable access to academic opportunities and institutional support. While global advancements in inclusive education have been significant, the UAE’s higher education sector faces unique challenges in accommodating students with LDs, particularly as technological disruptions, demographic shifts, and evolving policies reshape the broader educational landscape. This research investigates how a higher education institution in the UAE, such as RIT Dubai, might adapt its support systems for students with LDs, such as ADHD, dyslexia, dyscalculia, dysgraphia, and dyspraxia, under a range of plausible future conditions shaped by forces beyond its control. Guided by a Foresight and Future Planning (FFP) approach, the study integrates two strategic foresight methodologies: horizon scanning and scenario planning. Horizon scanning will identify emerging trends, technologies, and social changes likely to influence inclusive education. Scenario planning will synthesize these inputs to generate four plausible external environments (“inclusive education landscapes”) that may challenge or enable institutional efforts to support students with LDs. Drawing on qualitative and secondary data sources—including policy documents, academic literature, and stakeholder reports - this study aims to produce a strategic foresight framework that guides how UAE higher education institutions might respond to diverse futures. The expected outcomes include future-oriented strategies and recommendations for building adaptive, resilient, and inclusive support systems. By anticipating change and external uncertainty, this research supports institutional readiness and enhances the educational success of students with LDs in evolving learning environments
The Greatest Victory: Teaching Strategy and Peace Through Negotiation
No full textThis article examines how structured negotiation instruction, centered on the Circle of Value framework, enhances the critical and strategic thinking skills of cadets at the United States Air Force Academy (USAFA). Drawing on experiential learning, role-play simulations, and case studies—such as U.S.-China tensions over Taiwan—the article demonstrates how cadets apply integrative negotiation techniques to real-world geopolitical scenarios. The Circle of Value framework emphasizes interest-based negotiation, objective criteria, creative option generation, and the development of mutually beneficial outcomes. Through written analysis, live negotiation exercises, and reflective feedback, cadets build key competencies in communication, decision-making under pressure, and conflict resolution. The paper also explores how concepts such as BATNA, WATNA, and confidence-building measures equip cadets to approach complex international conflicts with clarity and foresight. Findings suggest that negotiation education is not only relevant for military leadership but essential for preparing officers to lead in an era of global uncertainty and strategic competition