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Strategies for Scaling Multiple Measures Assessment: Lessons from Arkansas
No full textInformed by a recent project to scale MMA throughout the state of Arkansas, this CAPR brief describes the state’s policy context, summarizes adoption efforts, and presents five strategies for other states that want to scale assessment reform
Earth Hunger: Agriculture, Settler Colonialism, and the Rise of the Global Grain Trade, 1846-1914
No full textThis dissertation argues that Britain's shift to free trade in 1846 moved British settler colonialism in Canada and Australia away from older trade and land monopolies and toward an imperial-agrarian system that sought to transform Indigenous lands into breadbaskets for the newly industrializing metropole. Liberal theories articulated in the 1840s created the ideological basis for new colonial legislation in the 1860s and 1870s, which led to the routine enclosure of land for settlers. Contrary to the utopian visions of interdependence and trade harmony painted by free traders in the 1840s, free trade policies led to an increase in British territorial conquest in the settler colonies. As foreign grain imports put pressure on the domestic agricultural sector in the 1870s, many began to view settler colonization as a release valve that could alleviate domestic population and food pressures. The 1870s were pivotal. As the imperial-agrarian system expanded to feed a growing industrial population in Britain, Indigenous communities in areas slated for grain production entered the agricultural economy and developed new political claims around land, even as colonial expansion undermined access to resources. Indeed, efforts to secure private property rights for farmers in new regions undermined the existing food supply, which led to subsistence crises, displacement, and land loss among Indigenous communities across Canada and Australia.
While new legal agreements emerged to reserve land for Indigenous peoples in the empire, the cyclical dynamic of agricultural development and improvement also foreshadowed the erosion of those agreements. The establishment of the grain economy set in motion a process of continual exploitation and expropriation, as colonists sought new arable lands—new extractive or commodity frontiers—to preserve or expand their margins. As settlers ran into both economic and ecological limits, such as exhausted soil and rising land prices, they sought to appropriate more Native land, establishing farmsteads in territories they had once considered marginal or that had been legally reserved for Indigenous communities. The grain economy in both places experienced significant growth in the 1890s and 1910s. These decades also saw intensified efforts to subdivide and allot reserve lands for sale to agricultural settlers. Examining the closure of Poonindie in South Australia and the surrender of the Siksika reserve in Alberta, my argument shows how land allotment was closely tied to the grain trade.
This dissertation uses the thread of the grain trade to bind together national histories within a British imperial system linked by trade. The story of the grain trade between 1846 and 1914, with its extensive land use, sprawling capital-intensive infrastructure, and integral position in the global and increasingly globalized food economy, gives us a more holistic picture of a period for which scholars have tended to write distinct histories of the British empire and its settler dominions in Canada and Australia. The project demonstrates that grain became the crop most closely associated with settler colonies, as the production of cash crops by family farmers simultaneously addressed both the population and agricultural crises in Britain. Grain was the flipside of the industrial economy, the crop that underwrote Britain's economic growth and upheld its imperial system
Environmental Health Monitoring of Air Pollutants and Flame Retardants: Measurement, Communication, and Health Implications
No full textPregnancy is a critical window of susceptibility to environmental exposures, impacting both maternal and child health. This dissertation is conducted within the Columbia Center for Children’s Environmental Health’s Fair Start Cohort and explores a broad spectrum of topics in environmental health research. It examines emerging contaminants such as organophosphate flame retardants alongside well-studied pollutants like organophosphate pesticides, employs novel exposure assessment methodologies, investigates the associations of these exposures with child health outcomes, and develops return-of-results documents to effectively communicate findings to cohort participants.
Chapter 1 includes background and overview of topics that will be covered in the following chapters
Chapter 2 explores community engagement in returning polycyclic aromatic hydrocarbon (PAH) exposure results to Fair Start participants. Using qualitative data analysis methodologies on data collected in focus group discussions, this study highlights the role of community feedback in refining environmental health reports. We found that participants exhibited varying levels of comprehension of PAH exposure sources, routes and information, survey data comparing feedback on initial and revised reports showed no significant difference in perceived readability or knowledge gained.
Chapter 3 quantitatively examines factors influencing the perception of PAH exposure results. Findings indicate that individuals with a college degree were significantly more likely to be surprised by their PAH exposure compared to those with lower educational attainment (OR = 5.60, p ≤ 0.05). Additionally, higher naphthalene levels were associated with decreased odds of being surprised (OR = 0.37, p ≤ 0.02). Participants with higher education and income levels tended to score higher on environmental health literacy measures, and emotional responses to exposure results were correlated with greater engagement in environmental health concerns.
Chapter 4 evaluates the effectiveness of silicone wristbands as passive samplers for measuring organophosphate ester (OPE) exposure in pregnant individuals by comparing wristband-derived and urinary biomarker measurements. A significant correlation was observed between triphenyl phosphate (TPHP) detected in wristbands and its urinary metabolite diphenyl phosphate (DPHP). However, chi-squared analyses revealed no significant categorical associations. Maternal age, education, and material hardship are predictors of exposure variation, emphasizing the need for further research to optimize wristband wear duration and refine exposure assessment methodologies.
Chapter 5 investigates the association between prenatal exposure to organophosphate pesticides and flame retardants with infant heart rate variability. Linear regression analysis indicates that OP pesticide metabolites (∑DAP) were associated with increased RMSSD during the play phase of the still-face paradigm (β = 2.80; 95% CI: 0.70-4.91) and negatively associated with the transition from play to still-face (β = -3.06; 95% CI: -4.91, -1.21). OP flame retardants did not show significant associations, suggesting that OP pesticides may contribute to parasympathetic nervous system dysregulation in infants.
Collectively, this research underscores the vulnerability of pregnant individuals and infants to environmental exposures and highlights the need for improved exposure assessment tools, risk communication strategies, and targeted interventions to mitigate potential health risks during this critical developmental period
Wildfires, Aridity, and the Pacific: Drivers of enhanced wildfire activity across the western United States since the 1980s
No full textWildfire in the western United States (US) is a natural disturbance that has become a destructive force impacting human life, human infrastructure, and ecosystems. Since 1984, the western US has experienced a ~250-300% increase in annual area burned and >1000% in forest area burned. A significant portion of the trends are driven by warming and drying from a combination of anthropogenic climate change and internal climate variability. A century of fire suppression has resulted in abundant fuel to burn, and the current amount of forest area burned is well below pre-industrial amounts. If climate is the main driver of burned area in the western US, how will climate variability and change continue to influence burned area across the western US? This is a guiding question for this Ph.D. dissertation and the field of study.
The goal of this Ph.D. is to expand our scientific knowledge of the teleconnected and physical drivers of burned area, from anomalous sea-surface temperatures (SSTs) to the flame front, utilizing the most up-to-date observations of climate, burned area, and SSTs; statistical modeling; and global atmosphere model outputs. We contribute to this field by answering three questions: (1) What drives annual forest area burned to respond exponentially to aridification? (2) How did the observed La Niña-like strengthening of the east-west tropical Pacific sea-surface temperature (SST) gradient contribute to western US wildfire extent in 1984–2022? (3) How have SSTs, internal atmospheric variability, and anthropogenic warming influenced western US burned area?
In Chapter 1, we find that annual area burned will continue to increase exponentially with linear increases in atmospheric warming and drying, due to the ability of individual fires to spread exponentially at their fireline when fuel is available. Annual burned area trends are dominated by the largest fires that have the greatest potential to grow exponentially in response to increased aridity—the warmth and dryness of the atmosphere.
In Chapter 2, we use this relationship in statistical models to predict annual are burned and link the role of observed Pacific SST patterns contributed by the Pacific Decadal Oscillation (PDO). We find that the observed tropical Pacific west-east sea-surface temperature (SST) gradient had a small but important role in enhancing the positive burned area trend since 1984, and was responsible for 20% of the 1984–2022 increase in wildfire extent.
In Chapter 3, we further explore the effect of SSTs on western US wildfire by forcing our burned area model with climate simulated by an atmospheric model that was forced with observed SSTs. Consistent with the results of Chapter 2, we find evidence that SST variability played a minor role in dictating western US burned area, explaining 18% of the variance, but more work is needed to disentangle the effects of SSTs from the effects of anthropogenic climate change. However, the simulations also suggest that the combination of observed SSTs and internal atmospheric variability had the potential over the past four decades to promote occurrences of annual burned areas that far exceed that of 2020, the current record holder.
Throughout this work, we demonstrate the importance of the relationships among SSTs, western US hydroclimate, and historical and future area burned. Our findings should motivate continued work to reduce uncertainty regarding how past and future anthropogenic forcing will affect tropical Pacific ocean-atmosphere coupling and associated climate teleconnections globally. Our findings should also promote continued preparedness for the likelihood of rapid increases in western US forest-fire activity that outpace current expectations and investment in remote sensing and in situ technologies that track wildfire activity in the western US
Flexible Photonic Accelerated High Performance Compute System
No full textThe rapid growth of artificial intelligence (AI) applications has driven the development of larger and more complex machine learning (ML) models. This trend has motivated the need for large-scale distributed compute clusters with significant networking and memory capabilities. However, current datacenter (DC) and high-performance compute (HPC) architectures are fundamentally limited by the bandwidth and energy constraints of electrically switched networks and tightly coupled memory units, resulting in data movement bottlenecks that limit both compute throughput and energy efficiency.
To address these challenges, this work explores the integration of silicon photonic based interconnects across the compute stack, from intra-node memory interfaces to inter-node compute networks. Specifically, we examine the architectural design space of integrating dense wavelength division multiplexing (DWDM)–based photonic links and switches in the compute system. To enable more efficient communication, we propose a hardware–software co-designed approach that optimizes collective communication algorithms based on the underlying optically reconfigurable topology. To support future deployment of photonic interconnects in HPC systems, we develop a quantitative methodology that evaluates their performance-power trade-offs for AI and ML applications.
We begin by introducing SiPAC, a silicon photonic accelerated compute architecture that improves distributed ML training through the co-design of a photonic physical layer and a collective communication algorithm. The physical layer exploits embedded DWDM photonic I/Os to bring high bandwidth optical connectivity directly to the compute unit and leverages resonator-based optical wavelength selectivity to enable a multi-dimensional all-to-all interconnect topology. The collective algorithm builds on this primitive to accelerate commonly used collective operations in ML training and to improve communication efficiency. To support multi-tenant environments, we extend this design with Flex-SiPAC, which leverages a novel wavelength reconfigurable multi-port transceiver and spatial-wavelength selective switch for flexible bandwidth steering across the network. Its co-designed collective algorithm supports multi-tenant scenarios and accelerates collective operations across diverse workloads.
We next introduce SiPAM, a silicon photonic accelerated memory pooling architecture. SiPAM integrates DWDM-based photonic I/Os directly along the compute die’s shoreline, replacing local high-bandwidth memories (HBM) and traditional electrical network interfaces with a unified, high-bandwidth optical communication domain. This architecture enables reconfigurable access to a disaggregated memory pool and decouples memory scaling from compute packaging constraints. In addition to identifying shoreline width as a critical architectural resource, we develop a quantitative optimization methodology to allocate compute resource, memory capacity and memory bandwidth based on workload demand.
Finally, we present a quantitative framework for evaluating reconfigurable network architectures in large-scale AI compute systems. This framework guides the future adoption of photonic switch and link technologies by analyzing performance trade-offs of varying reconfiguration latency, link bandwidth provisioning, and system power consumption. We develop two reconfiguration strategies and evaluate them on our proposed multi-dimensional all-to-all network topology designed to support hybrid parallelism with enhanced flexibility and energy efficiency.
Together, this work presents a systematic exploration of silicon photonic integration across the compute hierarchy, providing architectural and methodological insights toward building scalable, energy-efficient, and reconfigurable photonic infrastructure for emerging AI workloads
Roles of the MRX Complex in the Repair of Replication-Dependent Double-Strand Breaks
No full textIn this project, we tell three stories detailing the role of the Mre11-Rad50-Xrs2 (MRX) complex in the repair of replication-dependent double strand breaks (DSBs). The MRX complex is one of the first protein complexes to be recruited to the site of a DSB and is implicated in promoting DNA end resection, tethering sister chromatids together, and ensuring error-free repair of DNA lesions.
Here, we explore the role of the MRX complex in regulating end resection at replication-dependent DSBs. DNA end resection to generate 3 ssDNA overhangs is the first step in homology-directed mechanisms of DSB repair. While end resection has been extensively studied in the repair of endonuclease-induced DSBs, little is known about how resection proceeds at DSBs generated during DNA replication. We previously established a system to generate replication-dependent double-ended DSBs at the sites of nicks induced by the Cas9D10A nickase in the budding yeast genome. Here, we suggest that these DSBs form in an asymmetric manner, with one break end being blunt or near blunt, and the other bearing a 3 ssDNA overhang of up to the size of an Okazaki fragment.
We find that Mre11 preferentially binds blunt ends and is required to evict Ku from these blunt DSB ends. In contrast, the ends predicted to have 3 overhangs have minimal Ku binding, and resection at these break ends can proceed in a mostly Mre11-independent manner through either the Exo1 or Dna2-Sgs1 long-range resection pathways. These findings indicate that resection proceeds differently at replication-dependent DSBs than at canonical DSBs, and reveal that Ku selectively binds nearly blunt ends, potentially explaining why replication-dependent DSBs are poorly repaired by non-homologous end joining. Next, we study the role the MRX complex plays in tethering sister chromatids together, and specifically focus our work on the Rad50 subunit. The Rad50 subunit of MRX has several poorly understood structural motifs that may be relevant for replication-dependent DSB repair. Several mutants have previously been generated in the RAD50 gene that perturb different domains of the protein including the coiled coil and hook domains. Structural predictions suggest that the physical sister chromatid tethering activity of the MRX complex would require cooperative action between the coiled-coil and hook domains of Rad50.
Here, we demonstrate that mutations in the coiled-coil domain are especially sensitive to the nickase, while hypomorphic hook domain mutants are modestly sensitive. This sensitivity is compounded by the loss of the sister chromatid tethering factor CTF8, suggesting a genetic interaction between MRX-mediated sister chromatid tethering and PCNA driven sister chromatid cohesion. To directly test whether mre11∆ and other nickase sensitive mutants have sister chromatid tethering defects, we have designed a fluorescent microscopy-based assay using a LacO/LacI-GFP construct within the same replicon as the Cas9D10A cut site.
Using this assay, we demonstrate that the MRX complex is required for sister chromatid tethering during S-phase after the induction of a replication-dependent DSB formed on the leading strand template. In contrast, we find that both long-range resection machinery and the Rad51 recombinase are dispensable for maintaining sister chromatid cohesion of replication-dependent DSBs during S-phase. Finally, we note that structural rad50 alleles confer a spontaneous defect in sister chromatid tethering, suggesting a role for the MRX complex in tethering outside of DSB repair.
Finally, we extend our study of DNA damage repair to study Cas9 nickase-induced mutagenesis and repair pathway choice. Cas9 nickases Cas9D10A and Cas9H840A, collectively termed nCas9, have been proposed as less mutagenic genome editors compared to canonical Cas9 given that they induce single-strand breaks (SSBs) instead of double-strand breaks (DSBs). However, there are relatively few studies that address the frequency and spectrum of nCas9-induced mutations. Using a classical genetic assay for loss of function, we demonstrate that nCas9 is indeed mutagenic, although much less so than canonical Cas9. nCas9-induced mutagenesis is mitigated by the MRX complex, while the translesion polymerase Rev3 contributes to SSB-induced mutations.
Furthermore, Exo1 also contributes to nCas9 mutagenesis, presumably by generating ssDNA that must be repaired via fill-in synthesis. In contrast to Cas9 DSBs, we find no contribution of the non-homologous end joining (NHEJ) pathway in nCas9 mutagenesis. Consistent with this finding, we demonstrate that while Cas9 inductions results in small indels at the site of the gRNA, nCas9 induction results in indels and base substitutions both at, as well as hundreds of nucleotides away from the gRNA locus. This finding highlights the need for sequencing regions surrounding the gRNA target site for gene editing applications using nCas9
Becoming Great Lakes Theater: R(E)volutionary Shakespeare R(E)volutionizing American Theater
No full textThis dissertation speaks to and illuminates the process of the theatrical work in development, in rehearsal, and in performance done by the professional theatre company of Great Lakes Shakespeare Festival and its growth over the past six decades into Great Lakes Theater.
Located on the American north coast community of Cleveland, Ohio its journey includes interconnections through its series of artistic directors to the northeast’s tristate area, particularly Pennsylvania, New Jersey and New York, including associations with Carnegie Mellon University, Princeton University and McCarter Theatre, The Public Theater, New York, and internationally with The Globe Theatre, Stratford Upon Avon,The Royal Shakespeare Company in London, and The Abbey Theatre in Ireland.
Through the primary lens of an ensemble framework, emerging from highly innovative rehearsal work, performances, and educational programs and outreach with “Shakespeare” and “classic theatre” as a through line and catalyst for inspiring the development of modern drama and performance, transcending boundaries of how they should be defined, new visions are manifested theatrically. What is studied and uncovered reveals a process of dynamic discovery and choice making in drama, in theatre arts, and in both professional and educational performance.
Through a critical analysis and discussion of the four preliminary major artistic directors and their work with the Great Lakes Theater, leading into the 21st century, this inquiry also aims to identify some of the innovative best practices that become so intrinsic to effective and transformative ways of understanding and knowing dramatically, and that lead the art forms of theatre, performance, and education forward in vital and responsive ways to the society they serve.
A key component to what has been discovered in this part of the research process was the further revelation of the correlation between McCarter Theatre's beginnings at Princeton and its direct connection with the Great Lakes Shakespeare Festival's beginning and development. Its provenance began with Arthur Lithgow, who was the first artistic director for both theatres (with the Great Lakes preceding his work with McCarter) where each would eventually share the production work of the Great Lakes Shakespeare Festival ensemble that would go to McCarter for limited runs, becoming their primary company, as well, for some shared seasons.
Thereafter, the creative work of the Great Lakes Theater’s subsequent artistic directors and the theatre's history illustrate the further developments of linking it to other outstanding theatres, theatre companies, and educational theatre programs: including in neighboring Pennsylvania, through the work of Artistic Director Lawrence Carra, and extending into the tristate area of New York, New Jersey, and Connecticut, and with its affiliate, Cain Park Theatre, in Cleveland, Ohio, and in a unique way, to the Globe Theatre, London through the Great Lakes artistic director, Gerald Freedman, and to the Abbey Theatre, Ireland, and the Royal Shakespeare Company, England through the Great Lakes artistic director, Vincent Dowling.
Through the Great Lakes Theater's innovations in theatrical performance, drama, dramaturgy, and educational programs, and incorporating the groundbreaking work of its artistic directors and guest artists, its unique totality as a theater has impacted in its own microcosmic way, the larger American theatrical landscape in some profound macrocosmic ways: especially in terms of how Shakespeare and what may be considered classic theatre may become a catalyst for inspiring and creating revolutionary ideas and new works in contemporary theatre, in performance, and in education, for a new day.
Situated on the shores of Lake Erie in Cleveland, Ohio, in a much larger way, Great Lakes Theater is situated in spirit at the heart of the American Theatre, shaping its future in profound ways, yet to be imagined, and thereafter, to be realized…
Content Validity of the Friedreich Ataxia Rating Scale in Patients with Spinocerebellar Ataxia
No full textIntroduction
The Friedreich Ataxia Rating Scale–Activities of Daily Living (FARS-ADL) is a validated and highly utilized measure for evaluating patients with Friedreich Ataxia. While construct validity of FARS-ADL has been shown for spinocerebellar ataxia (SCA), content validity has not been established.
Methods
Individuals with SCA1 or SCA3 (n = 7) and healthcare professionals (HCPs) with SCA expertise (n = 8) participated in qualitative interviews evaluating the relevance, clarity, and clinical meaningfulness of FARS-ADL for assessment of individuals with SCA. Interviews were recorded, transcribed, coded, and analyzed by ATLAS.Ti v22 software.
Results
FARS-ADL concepts most frequently reported by individuals with SCA were difficulty walking (n = 7/7), falls (n = 6/7), speech difficulties (n = 4/7), and swallowing (n = 3/7). Individuals with SCA reported that all FARS-ADL items were relevant; Gait and Walking (n = 7/7), Bladder Function (n = 6/7), and Falling (n = 6/7) were considered extremely relevant. All HCPs (n = 8/8) reported that most FARS-ADL items were relevant to individuals with SCA; Quality of Sitting Position was considered least relevant. HCPs reported meaningful change as 1–2 point score change in individual FARS-ADL items (n = 7/7), 1–3 point change in total score (n = 6/6), and stability on any item and/or total score over ≥ 1 year, depending on SCA subtype (n = 5/8). Cognitive debriefing supported clarity and comprehension of FARS-ADL. Suggested improvements included refining response options for Dressing, Falling, Walking, and Bladder Function items.
Conclusion
The findings confirm the content validity of most FARS-ADL items for use in individuals with mild-to-moderate SCA1 and SCA3, and offer suggested improvements for response options
Race Equity Assessment for Leaders (REAL) 360 Tool to Develop Self-Awareness
No full textThe purpose of my research was to co-design and test a Race Equity Assessment for Leaders (REAL) 360 tool, which is a tool that supports organizational leaders in developing self-awareness of racial equity. This tool provides a ‘360-degree’ view of each leaders’ racial equity leadership through multi-directional perspectives through a: 1) self-assessment, which I co-designed and is the survey data that I collected for my research; and 2) a rater assessment of feedback from a peer colleague, a direct report, and a supervisor, which I co-designed. However, I did not collect or report on the rater survey data as my focus was on whether or not, and how, the tool helped leaders to develop self-awareness. This tool was designed in collaboration with ProInspire, a consultancy which supports social impact leaders and organizations to advance equity. This research fills a gap in the field and literature by contributing an assessment tool and implementing it in an organizational context to gain insight into leaders' self-awareness and acquisition of feedback on racially equitable leadership in their organization.
In my role, I served as a researcher and engaged in the following three research phases: 1. Phase I: Co-Development (Research and Design); 2. Phase II: Implementation (Testing and Revisions); and Phase III: Outcomes (Data Collection and Analysis). In Phase I, using an action research approach, I contributed to the iterative and collaborative process of co-designing the REAL 360. In Phase II, the tool was administered to leaders in non-profit, corporate, or higher education organizations. In Phase III, using a mixed methods approach, I collected quantitative data (pre-beliefs survey, demographics survey, and REAL 360 survey) and qualitative data (cognitive interviews with affinity focus groups and individuals and post-beliefs survey). My goal was to identify: 1) the perceived impact of the tool on race equity beliefs ; 2) areas where the tool could be impactful on race equity; and 3) how the tool may benefit from revision.
The quantitative findings suggest to me that racial equity beliefs and practices differ based on participants' racial identity (1. Black, Indigenous, and People of Color, BIPOC; 2.White) and age grouping (1. under 45; 2. 45 and over). Across both groupings, participants expressed a commitment to racial equity in their personal and professional lives. Participants 45 and over with more leadership experience, emphasized listening and aligning racial equity beliefs with organizational values to cultivate an inclusive workplace culture. Those under 45 who have exposure to social justice movements more recently in their adulthood, appeared more comfortable in expressing their racial identities. BIPOC participants rated themselves higher than White participants in advocating for racial equity policies and addressing advancement opportunities, which may reflect their lived experiences with workplace discrimination.
The qualitative findings reveal to me that the REAL 360 survey serves as an effective self-reflective tool. It encouraged participants to critically examine racial equity leadership practices and develop an awareness of beliefs and actions that contribute to more racially equitable outcomes in both their personal and professional lives. Also, participants revealed that learning should extend beyond the tool to include professional development.
Thus, the findings from this mixed methods action research study indicate to me that race and age contribute to leaders racial equity beliefs and practices. Also, these findings suggest to me that the tool can be supported with additional learning such as coaching sessions for leaders to interpret the tool’s feedback data and develop an action plan for more racially equitable practices. For future research to broaden the use of the tool to different organizations and to navigate potential resistance, organizations can highlight how inclusive leadership contributes to business outcomes like innovation, employee engagement, and overall performance
Wage Spillovers across Sectors: Evidence from a Localized Public-Sector Wage Cut
Full text linkWe study how institutional wage reforms in one sector spill over to other sectors by analyzing the public sector. We leverage the Japanese policy reform that cut public-sector wages only in certain municipalities and the institutional setting in which only young workers are eligible for public-sector jobs. We find that a 1% public-sector wage cut reduces the private-sector wages of young workers by 0.3%. This spillover elasticity is greater when public-sector jobs are more important as workers’ outside options. We also find that the migration outflow of young workers, consistent with the decline in their welfare in spatial equilibrium.
Keywords: spillover, wage reform, public sector, local labor market, Japan.
JEL classification: H72, J31, J38, R13, R50