VictorJuiz/thesis huggingface dataset:
Spatial Mapping of Tissue Properties Reveals Durotaxis in the Mouse Limb Bud
Keywords: cell movements
durotaxis
limb bud
morphogenesis
tissue stiffness

Numerous hypotheses invoke tissue stiffness as a key parameter that regulates morphogenesis and disease progression. However, current methods are insufficient to test hypotheses that concern physical properties deep in living tissues. For example, durotaxis, a form of cell migration in which cells are guided by stiffness gradients, has only been studied in vitro owing largely to the lack of tools to measure three-dimensional tissue properties in vivo. The role of durotaxis under physiological conditions remains unknown. Targeting spatial mapping of tissue properties and investigating durotaxis in vivo, this thesis focuses on (1) developing a new tool to achieve spatial mapping of tissue properties, (2) establishing the correlation between measured tissue properties and cell migration behavior, and (3) investigating the molecular basis of tissue properties and how it regulates durotaxis behavior. A 3D magnetic device was developed which generates a uniform magnetic field gradient within a space that is sufficient to accommodate an organ-stage mouse embryo under live conditions. The method allows rapid, nontoxic measurement of the three-dimensional spatial distribution of viscoelastic properties within mesenchyme and epithelium. Using the device, an anteroproximally biased mesodermal stiffness gradient was identified in the mouse limb bud. Along the stiffness gradient, cells migrate collectively to shape the early limb bud. The stiffness gradient corresponds to a Wnt5a-dependent domain of fibronectin expression. The findings challenge the notion that Wnt5a regulates cell migration through chemotaxis. Instead, Wnt5a modifies the tissue microenvironment to promote durotaxis in vivo. By conditionally knocking out the fibronectin within the mesenchyme, the stiffness gradient was abolished and the durotaxis behavior was arrested. Three-dimensional stiffness mapping enabled by the 3D magnetic device fills an important void in the current methods repertoire of measuring tissue properties and will facilitate the generation of hypotheses and potentially the rigorous testing of mechanisms of development and disease.
Health in All Policies Implementation at the Local Level: A Realist Explanatory Case Study
Keywords: Finland
Health in All Policies
Health Promotion
Implementation
Local
Public Policy

Background: Health in All Policies (HiAP) implementation can occur at the national, regional, and local government levels; however, factors contributing or hindering HiAP implementation at the local level are largely unexplored. HiAP is an approach to public policy that considers health and health equity in the development, implementation, and evaluation of policies in various government sectors. By addressing health and health equity in all sectors such as the transportation, housing, education, and agriculture sectors, HiAP addresses the larger social determinants of health, ultimately improving population health and decreasing inequity. Implementation of HiAP is often idiosyncratic to specific settings. Therefore, when aiming to understand how HiAP is implemented locally, it is imperative to consider context. Methods: A literature review on HiAP implementation at the local level was initially conducted, resulting in seven themes significant to implementation. Three of those themes were subsequently tested in an explanatory case study using realist methods. Semi-structured interviews were conducted with ten government employees in the municipality of Kuopio, Finland. In addition to the key informant interviews, grey and peer-reviewed literature were also analyzed to understand how HiAP is implemented in Kuopio, Finland, and uncover the relevant facilitating and hindering factors. Results: Findings support the importance of three factors in successful HiAP implementation at the local level: having/creating a common goal, having dedicated staff and local leadership, and the use of Impact Assessments. Strong evidence was found for each hypothesis, including a description of the underlying mechanisms of how and why strategies for HiAP work. Numerous contextual factors relevant to implementation success in this setting were also uncovered, including a mature HiAP setting, a culture of intersectoral collaboration, and a small city milieu, among others. Conclusion: Results of this realist case study augment the limited evidence available on HiAP implementation locally. Findings contribute to the growing body of knowledge in this field by providing a focus on descriptions of underlying mechanisms for HiAP implementation strategies in a Finnish municipality. Evidence provided can also be used strategically by local policy and decision makers to improve HiAP implementation efforts.
Predicting Asian Carp Spawning in Tributaries to the Great Lakes Basin
Keywords: Bio-physical Modelling
Hydrodynamic Modelling
Invasive Species
Temperature Modelling

Four invasive fish species, collectively known as Asian carps, have the potential to establish in the Great Lakes basin. To aid in prevention efforts, research was undertaken to understand factors influencing Asian carp spawning success. As Asian carp egg movement and hatching time are dependent on water temperature and hydrodynamics, this thesis focused on predicting in which rivers, and in which temperature and flow scenarios, successful hatching is more likely to occur. Chapter Two used existing temperature and velocity data to preliminary assess the spawning potential of eight Toronto-area tributaries. The results showed that Asian carp have substantial inter-annual variation in spawning potential and provided a method that had widespread applicability to narrow down potential spawning tributaries in the Great Lakes basin. Chapter Three created a novel coupling of three-dimensional (3-D) hydrodynamic river model and a 3-D Lagrangian Particle Tracker to model Grass Carp egg movement during a 2017 high-flow event in the Sandusky River, OH. The inclusion of 3-D aspects of flow allowed for the simulation of low-velocity dead zones that retain and re-suspend eggs, thereby increasing their residence time in rivers. The results showed that Grass Carp could spawn in shorter river lengths than previously predicted, thereby raising the potential of establishment in the Great Lakes basin. Chapter Four developed a coupled model on the Don River, ON to test the impact of potential barriers on spawning success. The results showed that in-river hatching rates could be greatly reduced by limiting upstream passage of carp and created a method that can be used to assess future potential barrier placements. Chapter Five added a novel temperature model coupling to the developed Sandusky River model to incorporate spatial and temporally varying temperature in the particle tracking. The results showed that the inclusion of varying temperature led to significant changes in in-river hatching rates. Climate-change scenarios model runs indicated that egg hatching times may reduce substantially due to anthropogenic climate change. The thesis results are directly applicable to prevention efforts in the Great Lakes and represent an advancement in the modelling of Asian carp spawning.
Benevolent Policies: The Politics of Welfare State Expansion in Southeast Asia
Keywords: Bureaucratic Capacity
International Organizations
Maternal and Child Health
Nutrition
Social Policies
Welfare State

Why do governments expand social policies? This question is central to our understanding of the welfare state. Conventional scholarship suggests that governments expand policies to placate groups with high political power or garner political support. Left unknown, however, is why governments expand social policies if clear, short-term incentives are absent. I draw attention to a class of social policies which serve groups with low political power and address issues with low visibility. I call these benevolent policies. Governments do not have strong incentives to prioritize, then formulate benevolent policies – yet some have sprung into action, introducing rapid policy change. What explains why governments expand benevolent policies? And why do some governments expand benevolent policies, while others do not? In contrast to the existing literature, which conceptualizes welfare state expansion as a product of conflict amongst societal groups, organized to protect or advance their interests, or of political manipulation and bargaining, I draw attention to the role of policymakers within the bureaucracy. I argue that policymakers are the primary source of policy reform. They mobilize in some governments, but not others, because of variation in bureaucratic capacity. This dissertation highlights the role of international socialization in triggering policymaker mobilization when bureaucratic capacity is high. Policymakers use the leverage provided by international pressure to deploy bureaucratic capacity and push through policy change. When bureaucratic capacity is moderate or low, however, other actors, such as civil society organizations or development partners, mobilize but are not as well positioned to facilitate reform. I develop this argument through a study of nutrition policies in Indonesia and the Philippines, and Laos and Cambodia. Nutrition policies, I contend, are emblematic of benevolent policies. Drawing upon nine months of fieldwork – including observations at a UN agency, 71 in-depth, semi-structured interviews, and observations at three closed-door regional health meetings – this project challenges influential theories of interest group strength, clientelism, and civil society mobilization. Instead, I show that policymakers are the defining agents of change. This dissertation therefore lays the foundation for future research on benevolent policies and invites further exploration of the conditions under which they expand.
Adam's Wisdom and Israel's Law: Natural Law in Early Judaism
Keywords: Adam
Genesis
Natural Law
Revelation
Sinai
Wisdom

When we think of “natural law” we may think of Thomas Aquinas, the Greco-Roman philosophers, or the rabbinic Noahide law. I show that in the Second Temple period Jews had their own way of talking about natural law. Their approach precedes Aquinas and the rabbis, and it is contemporary with the Stoic philosophers. They used Adam and Eve to formulate concepts concerning moral knowledge and moral agency including natural law. Aside from the opening chapters of Genesis, the Hebrew Bible shows little interest in Adam and Eve. By comparison, Second Temple Jewish literature developed various interpretive traditions concerning the primordial pair. In one tradition God endowed Adam and Eve with wisdom, law, or commands. In this “Adam’s wisdom” tradition, when Adam and Eve (i.e., humanity) receive wisdom they know their moral obligations. This tradition occurs in a variety of early Jewish literature (ca. 300 BCE–200 CE), and it articulated diverse ideas of revelation, moral knowledge, and moral agency. This project compares Adam’s wisdom in four texts—Sirach, the Qumran Thanksgiving Psalms (i.e., 1QHodayota), Paul’s letter to the Romans, and 4 Ezra. This comparison illumines the diverse configurations of moral knowledge and moral ability in early Judaism. Of special interest is a literary tradition that blends Adam’s wisdom with Israel’s reception of the law at Sinai. This interweave of scriptural threads forms a tapestry of natural law. Adam’s wisdom and Israel’s law is a prominent and repeated literary feature of Sirach, Romans, and 4 Ezra, and this project shows the varied argumentative, rhetorical, and formative purposes for which it was deployed. Adam’s wisdom and Israel’s law also illuminates how Jews of the Greco-Roman period negotiated Jewish and gentile identities in light of God’s revelation to Adam (i.e., humanity) and God’s revelation at Sinai. While the Hodayot do not interweave Adam’s wisdom and Israel’s law, they provide a counterbalance to the other texts. Instead of universal moral knowledge, the Hodayot use Adam to portray universal moral ignorance and inability, and Adam’s wisdom signifies the esoteric knowledge possessed exclusively by the Qumran community.
The SuperBIT Hardware Design and a Constraint of the Tensor to Scalar Ratio r from the Spider I Polarized CMB Maps
Keywords: Cosmology
Weak Lensing

]Scientific ballooning experiments offer a number of advantages over space and ground based alternatives: they are lower cost, faster to deploy, and easily upgraded in contrast with satellites. As well, the ballooning environment, while quite harsh, has the benefit of raising the experiment above 99% of the atmosphere, as opposed to ground based experiments which are subject to seeing and absorptivity of the atmosphere even when atop the highest mountains. The subjects of this thesis are two examples of scientific ballooning experiments; Spider I, a cosmic microwave background experiment, and SuperBIT, an optical and near-UV observatory. The Spider I experiment is designed to constrain the tensor to scalar ratio, r; a parameter informing the allowed potential energy of the inflationary epoch thought to precede the standard cosmological model, ΛCDM. This thesis contains an analysis of the Spider CMB maps for a constraint on the parameter r, and includes the development of a bin to bin correlation transfer matrix, as well as the development of an auto-spectrum null-test procedure used for data qualification. The SuperBIT experiment is designed for cluster-galaxy weak gravitational lensing measurements to provide calibration data for future satellite experiments which are hoped will break the 1.5σ contention between the leading measurements of the cosmological parameters Ω M and σ8 taken from CMB data compared with that of other low redshift, Sunayev Zel’dovich measurements. To date no lensing data has been taken; however, a long duration flight is tentatively scheduled for 2021. This thesis contains a description of my contributions to the development of the SuperBIT hardware systems and optics.
The Bounds of Legality for Family Lawyers: Is the Law Enough?
Keywords: Dispute Resolution
Family Law
Legal Ethics
Legal Theory

Positivist legal ethics theories provide that a lawyer’s role is to pursue her client’s interests within the bounds of legality. In the context of family law, the law allows for objectionable conduct by a lawyer which may even be harmful where there is family violence or children. In essence, there is tension between the positivist explanation of a lawyer’s role, and what that explanation allows a family lawyer to do. In this thesis, I provide a comprehensive examination of the canons of legal ethics theory as they explain a lawyer’s role. I defend positivist legal ethics theories and examine how they conceptualize the bounds of legality. Following from that theoretical account, I apply positivism to family law and argue that the considerable discretion provided by family law creates too much room for bad behaviour by family lawyers. Finally, I refute the idea that there are additional reference points to guide professional judgement that are unique to family law, and I argue for reform.
Experiences of Students Who Have Been Suspended or Expelled from School
Keywords: Adverse Childhood Experiences
community and school violence
school discipline
suspension and expulsion
systemic racism and inequality
Trauma

Background Violence and adversity disproportionately affect students who are Black or Indigenous, come from lower socioeconomic (SES) communities and those with special education needs. These same populations are disproportionately suspended and expelled (disciplinary exclusion). The role of adversity in disciplinary exclusion, however, is rarely explicitly considered. It is difficult to understand students’ and their behaviours, however, if adversity is unacknowledged. Methods This three-paper dissertation presents a constructivist grounded theory analysis of 31 semi-structured interviews with students who have been suspended or expelled (n=15) and the multidisciplinary staff who support them (n=16), in two urban and suburban school boards in Ontario, Canada. The purpose of this study was to understand the experiences of students who have been suspended or expelled. The following research questions were addressed: 1) What are the experiences of students who have been suspended or expelled leading up to and including expulsion? 2) What factors do participants (staff and students) feel contributes to a suspension or expulsion?; and 3) What systemic factors (school, community, family) have positively or negatively influenced students’ personal and academic success? Student participants ranged in age from 14 to 19. Most students in the sample were male (n=11), Black (n=10), or identified as having special education needs (n=9). Results Students in this study had experienced multiple and diverse forms of adversity, including conventionally defined adverse childhood experiences (ACEs), as well as systemic racism and inequality, and community and school violence. All students noted the importance of connection with school staff however, an interactive social process emerged within which three identified factors (bias, coping behaviours and limited resources) blocked this connection. Implications The findings call into focus the role of disproportionate exposure to adversity for students who are suspended and expelled. These findings are consistent with recommendations to expand conventional ACEs. The emergent interactive social process is influenced by disproportionate exposure to adversity, which may be unacknowledged as traumatic among students who are suspended or expelled. When expanded forms adversity are unacknowledged student experiences and the ways they are coping can be misunderstood. Policy, practice and research must reflect trauma-informed, relationship-based and culturally aware/responsive strategies.
Etiology of Vascular and Inflammatory Changes in the Central Nervous System after Experimental Subarachnoid Hemorrhage
Keywords: Inflammation
Macrophages
Microvasculature
Subarachnoid hemorrhage

Subarachnoid hemorrhage (SAH) is a type of hemorrhagic stroke that is associated with high mortality and morbidity. Though bleeding is confined to the subarachnoid space, there is significant parenchymal brain injury after SAH. The development of brain injury after SAH is widely studied with varying conclusions, though growing evidence indicates that changes to the microcirculation and inflammation may play important roles in this process. In this thesis, I used in vivo and ex vivo imaging and molecular techniques to better characterize how SAH affects the microcirculation and inflammatory cells in central nervous system tissue. In the first part, I studied the microcirculation using two-photon laser microscopy in vivo, and confocal imaging ex vivo. I found that SAH causes microvascular disturbances in the somatosensory cortex within minutes of SAH, which last for hours after the ictus. These microvascular changes persist for days in regions adjacent to the blood clot, but not in distal brain regions. In the second part, which focuses on the inflammatory response, I first characterized the distribution and clearance of blood in the central nervous system after SAH by modifying an SAH animal protocol to track erythrocytes. Erythrocytes were found throughout the ventricular and subarachnoid spaces, but also extending to perivascular spaces within the brain tissue. We found that perivascular and leptomeningeal macrophages were directly involved in the uptake of blood after SAH. In experiments where these macrophages were depleted, we found that specifically timed deletion could improve outcome after SAH. Lastly, I found that meningeal macrophages in the dura also are activated after SAH, and thereby represent another potential source of central nervous system inflammation. Based on the work presented in this thesis, I propose that the cerebral microcirculation, and perivascular and meningeal macrophages are essential to the development of injury after SAH and may be potential therapeutic avenues.
Microfluidic Frameworks to Elucidate Mass Transfer Dynamics in Sheared Dispersions
Keywords: Emulsions
Mass transfer
Microfluidics
Mixing
Multiphase flows
Suspensions

Innovations in the area of microfluidics have enabled researchers to develop microfluidic techniques, as an alternative to macroscale methods, to measure scale invariant quantities pertinent to mass transfer operations. The ability to control variables precisely and accurately, and the possibility of employing analytical approaches owing to simpler fluid flow equations makes microfluidics an attractive platform for such measurements. This thesis establishes microfluidic protocols and theoretical frameworks to measure thermodynamics and kinetic parameters pertinent to mass transfer dynamics in three classes of sheared dispersions: gas-in-liquid dispersions, emulsions and rigid particle suspensions. The first platform is designed to measure gas solubility and diffusivity in a liquid by observing the shrinkage of a train of relatively long bubbles flowing through a microchannel. This data is analyzed by using a mathematical model that considers the local concentration gradients and the flow profiles, without resorting to the computationally expensive, full numerical simulations of the fluid flow and concentration distribution equations. The developed microfluidic platform can be applied to diverse gas-liquid reaction systems to determine the equilibrium and kinetic parameters conveniently and rapidly. The second platform is an automated feedback-control based hydrodynamic trap, that has enabled control and observation of a Hele-Shaw oil droplet for long residence times (minutes to hours). It has allowed us to measure oil solubility in an aqueous medium by analyzing the temporal radii using an appropriate mass transfer theory. This platform can also be used to monitor solvent extraction dynamics in the synthesis of polymer microparticles. The final platform is designed to measure mixing lengths of a tracer in moderately concentrated suspension flows (>30% volume fraction of rigid, spherical particles). For such suspensions, mixing is understood to result from a complex interplay between three mechanisms: (a) molecular diffusion, (b) shear-induced self-diffusion, and (c) second normal stress difference induced secondary convection. A comprehensive numerical study and a thorough scaling analysis is carried out to outline this interplay. Using confocal microscopy and a fluorescently-labeled dye in the medium, we present the first experimental study that observes the dynamic process of mixing in suspensions due to secondary currents. Our experiments also reveal a fourth mechanism of mixing - hydrodynamic instabilities arising from nonlinear effects at high volume fractions. The quantification and modeling of the fundamental mechanisms of mass transfer will serve as the basis for the prediction of solute mixing rates in sheared suspensions at larger scales.