Greek Mythology Vocabulary Building

The guiding question addressed in this Capstone is: How will the use of task-based vocabulary activities to support literacy development affect the vocabulary acquisition of elementary Korean English language learners? It documents one teacher’s curriculum development of two units that offer a new perspective to ELL vocabulary acquisition by building vocabulary using morphological training then access and build on background knowledge through practical applications which lead to higher comprehension. This project explores a) the role that task-based curriculum plays on literacy development focused on the development activities that supports the vocabulary development of elementary Korean English language learners using Greek root words and affixes beyond vocabulary word lists. b) Uses grapheme, phoneme, morpheme awareness, integrated in a way that helps students understand how words are built and takes the form of a unit plan adapted from Understanding by Design Backward (Tomlinson & McTighe, 2006). c) Activates student knowledge in the application phase through personalized communication practice

Enhancing Platforms at the Interface of Viruses and Directed Evolution:

Thesis advisor: Abhishek ChatterjeeDirected evolution is a powerful technique to expand chemical space in biological systems. In particular, this method has been used to develop cellular machinery to enable genetic code expansion (GCE), the incorporation of unnatural amino acids (UAAs) into proteins during the translation process. GCE relies on evolving an aminoacyl tRNA synthetase (aaRS) and tRNA pair from a different domain of life to incorporate a UAA into proteins in their new host, as these evolutionarily distant pairs are less likely to be cross-reactive with host pairs. The aaRS and tRNA must meet a number of conditions to be useful for GCE: the pair must be orthogonal (non-cross-reactive) to the host’s native aaRS/tRNA pairs in order to ensure site-specific UAA incorporation; the aaRS must have an active site suited to accept the shape of the UAA; and the tRNA must cooperate with the host ribosome, elongation and release factors, and other translational machinery to efficiently incorporate the UAA into the protein. Numerous aaRS/tRNA pairs have been evolved to allow incorporation of diverse UAAs in bacteria due to the tractable nature of these organisms for directed evolution experiments. While an aaRS evolved in bacteria to charge a novel UAA can be used in eukaryotes, tRNAs cannot be evolved for GCE in bacteria and then used in eukaryotes because they will not have evolved in the presence of the correct translational machinery. It is necessary to evolve tRNAs directly in their host cells. Unfortunately for researchers working on GCE in mammalian cells, it is difficult to perform directed evolution on small gene products in these hosts. Transformation efficiency in mammalian cells is poor, and transient transfection yields heterogeneous DNA distribution to target cells, making selection based on performance of individual library members impossible. Viruses are an ideal DNA delivery vector for mammalian cells, as production of recombinant viruses allows control over library member generation, and viruses can be delivered with exquisite copy number control. The Chatterjee lab recently developed a platform, Virus-Assisted Directed Evolution of tRNAs (VADER), using adeno-associated virus (AAV) to evolve tRNAs for GCE directly in mammalian cells. While VADER is the first directed evolution platform that allows the evolution of small gene products in mammalian cells, its efficiency is limited by its continued reliance on transient transfection to deliver non-library DNA that is necessary for the production of rAAV. To overcome this limitation, baculovirus delivery vectors were developed to boost DNA delivery and AAV capsid production to improve virus production efficiency during selections. VADER allows the evolution of tRNAs to incorporate certain UAAs, but the technique relies on installing a UAA into the AAV capsid, which is sensitive to disruption caused by slight modifications in structure. To expand the scope of VADER to evolve tRNAs for UAAs that cannot be incorporated into the AAV capsid, an alternate selection handle (Assembly Activating Protein, or AAP) was deleted from the genome and provided in trans to incorporate 5-hydroxytryptophan (5HTP). Incorporating the UAA into this flexible protein allows UAA-dependent production of AAV and expands the scope of tRNAs that can be evolved in mammalian cells.Thesis (PhD) — Boston College, 2021.Submitted to: Boston College. Graduate School of Arts and Sciences.Discipline: Chemistry

Planning Satellite Swarm Measurements for Earth Science Models: Comparing Constraint Processing and MILP Methods

We compare two planner solutions for a challenging Earth science application to plan coordinated measurements (observations) for a constellation of satellites. This problem is combinatorially explosive, involving many degrees of freedom for planner choices. Each satellite carries two different sensors and is maneuverable to 61 pointing angle options. The sensors collect data to update the predictions made by a high-fidelity global soil moisture prediction model. Soil moisture is an important geophysical variable whose knowledge is used in applications such as crop health monitoring and predictions of floods, droughts, and fires. The global soil-moisture model produces soil-moisture predictions with associated prediction errors over the globe represented by a grid of 1.67 million Ground Positions (GPs). The prediction error varies over space and time and can change drastically with events like rain/fire. The planner's goal is to select measurements which reduce prediction errors to improve future predictions. This is done by targeting high-quality observations at locations of high prediction-error. Observations can be made in multiple ways, such as by using one or more instruments or different pointing angles; the planner seeks to select the way with the least measurement-error (higher observation quality). In this paper we compare two planning approaches to this problem: Dynamic Constraint Processing (DCP) and Mixed Integer Linear Programming (MILP). We match inputs and metrics for both DCP and MILP algorithms to enable a direct apples-to-apples comparison. DCP uses domain heuristics to find solutions within a reasonable time for our application but cannot be proven optimal, while the MILP produces provably optimal solutions. We demonstrate and discuss the trades between DCP flexibility and performance vs. MILP's promise of provable optimality

Eating Disorder Treatment Access Climate Assessment in the United States: Perceived Inequities Among Reported Treatment Seekers

Objective: Although eating disorders (EDs) are associated with high rates of psychological and physical impairments and high mortality rates, only 20% of those with EDs will receive treatment. No comprehensive treatment access climate assessment has occurred, and little is known about how barriers to treatment access differ across demographic (e.g., ethnic minorities) and diagnostic groups. The purpose of this study was to comprehensively assess the ED treatment access climate and how this climate might vary in subpopulations. Method: ED treatment seekers (N = 2,018) completed an online assessment of clinical demographics, anthropometrics, barriers to ED treatment access, and ED symptomatology. Analyses were conducted to describe treatment access barriers, to compare rates of barriers to treatment access across demographic groups, and investigate relations among barriers to treatment access and ED symptoms. Results: Financial barriers (e.g., lack of insurance coverage) were the most frequently reported barriers to treatment access. Those with historically underrepresented identities and with an Other Specified Feeding and Eating Disorder (OSFED) diagnosis reported more financial, geographic, diagnostic, sociocultural, and treatment-quality barriers relative to historically represented identities (e.g., white, cisgender women). Higher frequencies of reported barriers to treatment access were associated with higher ED symptoms and poorer illness trajectories. Conclusions: Financial barriers are the most significant barrier to accessing treatment. Barriers to treatment access disproportionally affect underrepresented groups and those with an OSFED diagnosis

Barriers to Eating Disorder Treatment Access in the United States: Estimates of Perceived Inequities Among Reported Treatment Seekers

Despite having the second highest mortality rate of any psychological disorder (Arcelus et al., 2011; Crow et al., 2009; Herzog et al., 2000; Keel et al., 2003; Smink, Van Hoeken, & Hoek, 2012), most individuals with an eating disorder (ED) never access treatment (Hart et al., 2011). Considering that the United States (US) is one of the wealthiest countries in the world, access to healthcare is generally abysmal (Hoffman & Paradise, 2006), such that many individuals, such as those with “pre-existing conditions” (e.g., cancer; Weaver et al., 2010), forgo treatment (e.g., dental, medical, mental) for financial reasons. Further, approximately 18% of nonelderly Americans (46 million) are uninsured and approximately 61% rely on their employer to access health insurance (Hoffman & Paradise, 2006). The consequences of these and other health disparities as they apply to the EDs are largely unknown. The first step in understanding the impact of barriers to ED treatment access in the US is to first quantitatively describe the healthcare climate and barriers to treatment access that treatment-seeking individuals with EDs face. A few critical studies have begun to elucidate ED treatment access inequities (Innes, Clough, & Casey, 2016) although these studies have focused specifically on barriers to treatment seeking rather than barriers to treatment access. Additionally, a few studies have found that these inequalities disproportionately affect historically underrepresented groups (e.g., Black, Indigenous, and People of Color, gender and sexual minorities; Sinha & Warfa, 2013; Sonneville & Lipson, 2018). Due to the several gaps in the literature, this study aims to: (1) comprehensively assess systemic and intrapersonal treatment access barriers simultaneously, and (2) provide initial estimates of the prevalence of barriers to treatment access in the U.S. Therefore, the current study (N = 2238) extends previous research by quantifying barriers to treatment access in the eating disorders across several domains, including self-reported lifetime financial (e.g., insurance, steps taken to afford care), diagnostic (e.g., assessment access, misdiagnosis), treatment quality (e.g., harmful comments from providers, discharge without step down care), sociocultural (e.g., stigma, weight stigma), and geographical (e.g., specialized care in state) barriers in a large sample consisting of participants in all 50 U.S. states. Additionally, the current study seeks to examine the prevalence of specific domains across subpopulations, and to examine impact of barriers on reported ED symptomatology. Finally, the current study seeks to explore treatment experiences, specifically related to weight stigma in medical and ED communities