VictorJuiz/thesis huggingface dataset:
Essays on the Economics of Behavioral and Environmental Changes

Climate change is set to have a significant economic impact, affecting our behavior and changing the ways we produce and consume. This dissertation illustrates different channels through which environmental change has already been impacting our economy and highlights potential measures and market designs to mitigate future costs. The first two chapters of this dissertation leverage historical weather data to assess the market and behavioral responses to extreme temperature shocks. Chapter 1 utilizes European electricity markets data to assess the non-linear relationship between weather and energy cost. The analysis of spot market electricity prices reveals that estimates of the energy cost due to climate change which rely solely on consumption are significantly biased downward. In addition, the creation of a ``unified'' European market through regional market integration has contributed to drastically lower the impact of extreme temperatures on electricity price. Chapter 2 demonstrates that warm temperatures are associated with a rise in violent crime in the US. I further investigated the effect of extreme weather on police officer behavior using original and novel crowd-sourced data on civilian deaths involving police. The results indicate that fatal shootings increase proportionately to the growing number of violent crimes during warmer days. Taser use and physical restraints --- two controversial uses of force --- increase significantly on such days regardless of the threat level, indicating a need to reevaluate their usage. Finally, chapter 3 explores the distribution of human attention to moments in time using Google search data. Attention is a key parameter in the field of environmental economics as public policies enacted today are a direct function of how much people value the past, current, and future states of the economy. The results suggest strong common patterns of thought with respect to time, however recent trends and regional variations indicate that some non-biological factors can alter these patterns slightly.

Advisor: Hsiang, Solomon
Auffhammer, Maximilian
Conservation of a socio-ecological system: Indigenous hunting communities and bearded pigs in Malaysian Borneo

In a telecoupled world, people and ecosystems are intricately linked across vast spatial scales. Consumption patterns, disease, and other factors on one side of the world often reverberate powerfully to shape landscapes, socio-cultural practices, and wildlife distributions in farremoved locales. These new realities require sustainability to be fundamentally achieved at global scales in order to have lasting sustainability for people and wildlife at local and regional systems. To consider these themes, my collaborators and I study a socio-ecological system of Indigenous hunting communities and bearded pigs, a cultural keystone species, in Malaysian Borneo. In Chapter 1, we build an intellectual framework that considers the ways that telecoupling unfolds in Sabah and Sarawak, driving oil palm expansion, deforestation, and socialchange. In Chapter 2, we carry out single-season, single-species occupancy models for bearded pigs that show the association of both socio-cultural factors (e.g. ethnicity and hunting accessibility) as well as environmental factors (e.g. protected area status and elevation) on bearded pig distributions across Malaysian Borneo. In Chapter 3, we document ways that oil palm plantations and urbanization have changed bearded pig hunting practices among Indigenous Kadazandusun-Murut (KDM) hunters in Sandakan District, Sabah. We also describe the ways that some hunting motivations, such as meat provision and gift-giving, have endured despite widespread changes in land-use. In Chapter 4, we investigate intergenerational hunting knowledge transfer within KDM hunting communities, also in Sandakan District, Sabah. Almost two-thirds of respondents had not, or were not intending, to pass on their hunting knowledge to their children. Moreover, many respondents reported low hunting interest among the younger generation, suggesting diminished importance of hunting practices in the future among KDM communities in Sabah. Together, our findings highlight the salience of social practices and Indigenous knowledge for bearded pig distributions in Malaysian Borneo. Our results also raise important questions about the nature of conservation values and human-wildlife interactions in a world in which hunting practices, and connection to nature more broadly, are in decline. Ancient socio-ecological links—including hunting, recreation, and other social practices—highlight profound connection points for long-term sustainability of human cultures, biophysical landscapes, and wildlife communities.

Advisor: Brashares, Justin S.
Potts, Matthew D.
High Order Partitioned Fully Implicit Runge-Kutta Solvers for Fluid-Structure Interaction

In this work, we develop and analyze a partitioned implicit time integration method designed for fluid-structure interaction (FSI) modelling using discontinuous Galerkin (DG) discretizations and fully implicit Runge-Kutta (IRK) methods. The discontinuous Galerkin method is a high-order finite element method used for fluid simulations on unstructured meshes. We take a partitioned approach, modelling the structures separately and limiting communication between structure and fluid by use of a prediction-correction framework. We verify the high-order accuracy, the stability, and the performance of our method on simple model problems including a one-dimensional sprung piston and a two-dimensional pitching airfoil with prescribed vertical motion and a torsional restoring force, both with structures of two degrees of freedom. Finally we apply our method to the standard problem of a cantilever beam shedding vortexes with two sets of parameters, and a vibrating tuning fork problem. Both these final applications consist of fluids modelled on fully unstructured meshes of high-order triangular elements deformed by radial basis functions according to the structure motion, and structures modeled using a neo-Hookean formulation and discretized using standard continuous finite elements./nOur scheme fully decouples the implicit solutions of the structure and the fluid, with communication limited to boundary conditions and mesh deformation. We present our method with two variations, one using explicit methods for predicted quantities and another using implicit. We implement our method up to seventh order, and compare its cost with standard Diagonally Implicit Runge-Kutta methods where possible. Our findings are that this new method can be significantly cheaper, in particular for the more complex cantilever problem, and it also has better stability properties.

Advisor: Persson, Per-Olof
The Growth & Transformation of Galaxies Across Cosmic Time

Deep surveys have allowed us to precisely chart the evolution of galaxies from billions of years ago through to the present day. We’ve found that galaxies in the distant past are dramatically different than those in the local universe: the stellar masses, sizes, structures, star formation rates, gas contents, and kinematics of galaxies all evolve with redshift. One of the few constants is the bimodality between star-forming and quiescent galaxies, which persists across a wide redshift range. Despite these observational advances, the exact nature of the physical processes governing the growth and transformation of galaxies remain unknown./nThe first section of this thesis concentrates on the growth of galaxies. Previous studies have used half-light radii to trace the evolution of galaxy sizes. However, radial color gradients cause the light and mass profiles of galaxies to differ, biasing these measurements. I develop and test multiple techniques for measuring the mass profiles of galaxies from high-resolution multi-band Hubble Space Telescope imaging, then use these techniques to create the largest- ever catalog of galaxy half-mass radii at 0 ≤ z ≤ 2.5. This unique catalog enables me to correct for biases in previous studies of size evolution and discover that galaxies grow much more slowly than previously thought. I then examine how the structures of galaxies change as they age along the quiescent sequence, providing support for a merger-driven “inside-out” growth mechanism. Finally, I investigate how the structures of galaxies change as they gradually move up the star-forming sequence towards quiescence. These results pave the way for a new interpretation of the star-forming size-mass relation, and provide evidence for multiple distinct pathways for galaxies to shut down their star formation./nThe second section of this thesis addresses the transformation of galaxies from star-forming to quiescent. Because stars form out of cold molecular gas, most theoretical mechanisms for this “quenching” process rely on heating, depleting, or removing molecular gas reservoirs. Post-starburst galaxies, whose spectra indicate that they have recently and rapidly shut down a major burst of star formation, are the ideal laboratory to test these theoretical quenching mechanisms. I introduce the SQuIGGLE multi-wavelength survey of intermediate-redshift post-starburst galaxies. After selecting ∼1,300 of these rare recently-quenched galaxies by their Sloan Digital Sky Survey spectroscopy, I perform detailed Bayesian spectral modeling to constrain their star formation histories. I also present Atacama Large Millimeter/submillimeter Array measurements of the CO(2–1) line in two SQuIGGLE galaxies. I show that, in contrast to theoretical predictions, these recently-quenched galaxies can retain large molecular gas reservoirs. These puzzling observations challenge our understanding of how galaxies shut down their star formation.

Advisor: Kriek, Mariska
Self-Managed Abortion: Addressing Methodological Challenges in Measuring Safety, Incidence, and Effectiveness

Barriers to safe, effective, and affordable methods of abortion include restrictive laws, unwilling or untrained providers, long wait times, high costs, lack of services in the public sector, and abortion stigma. These barriers prevent individuals from exercising their fundamental human right to choose if and when to have a child, and threaten bodily and reproductive autonomy. Self-managed abortion with medication—defined as ending one’s own pregnancy outside of a formal healthcare setting using misoprostol alone or in combination with mifepristone—can be safe and effective; however, there is a lack of research on its incidence, safety, and effectiveness, and there are considerable methodological challenges in its assessment./nThis dissertation aims to address key methodological challenges in the measurement of self-managed abortion via the following approaches: development of a conceptual framework for measuring abortion complications; assessment of a novel application of respondent-driven sampling (RDS) to study the incidence of abortion; and estimation of the effectiveness of self-managed medication abortion in probabilistic bias-adjusted models./nChapter 1 describes the development of a framework for measuring complications and outcomes from medication abortion based on self-report, informed by thematic analysis of in-depth interviews from people with various abortion experiences in Argentina, Indonesia, Mexico, Nepal, Nigeria, and Sierra Leone. Findings from this analysis demonstrated that individuals describe and quantify their experiences with bleeding and cramping in varied ways, and highlights the need for a person-centered framework that emphasizes the individual’s preferences around medical care seeking. Chapter 2 is a methodological assessment of an RDS study on the incidence of abortion in Soweto, South Africa, and explores the implications of potential violations of RDS assumptions on incidence estimation. In this study, several key assumptions of RDS were not met, yielding potentially biased estimates of abortion incidence. Chapter 3 utilizes data from a prospective observational study assessing the effectiveness of self-managed medication abortion among callers to accompaniment groups and safe abortion hotlines in Argentina and Nigeria, and demonstrates a Monte Carlo Sensitivity Analysis approach to adjusting for misclassification and selection bias. After adjusting for potential misclassification, selection bias, and enrollment of ineligible participants, self-managed medication abortion remains highly effective, conditional on our assumptions around the chosen bias parameters.Findings from this dissertation will contribute to the development of a self-report questionnaire to measure complications and outcomes from medication abortion; highlights the pitfalls of respondent-driven sampling and offers potential remedies; and can be used to inform future analyses of the effectiveness of self-managed medication abortion based on observational data.

Advisor: Ahern, Jennifer
Electric-field noise scaling and wire-mediated coupling of remote ions in a novel elevator surface trap

In this work, we present the design, fabrication, and operation of a novel surface-electrode Paul trap that produces a radio-frequency-null along the axis perpendicular to the trap surface. This arrangement enables control of the vertical trapping potential and consequentially the ion-electrode distance via dc-electrodes only. We demonstrate confinement of single 40Ca+ ions at heights between 50 μm and 300 μm above planar copper-coated aluminum electrodes. Laser-cooling and coherent operations are performed on both the planar and vertical motional modes. This architecture provides a platform for precision electric-field noise detection, trapping of vertical ion strings without excess micromotion, and may have applications for scalable quantum computers with surface ion traps.In our novel surface trap, we probe electric-field noise for ion-surface distances d between 50 μm and 300 μm in the normal and planar directions. We find the noise distance dependence to scale as d^−2.6 in our trap and a frequency dependence which is consistent with 1/f noise. Simulations of the electric-field noise specific to our trap geometry provide evidence that we are not limited by technical noise sources. Our distance scaling data is consistent with a noise correlation length of about 100 μm at the trap surface, and we discuss how patch potentials of this size would be modified by the electrode geometry. Finally, we achieve coupling between the motions of trapped ions separated by 620 μm. Our results are marked by the implementation of remote ion-ion interactions enhanced via an electrically floating metallic wire in an RF Paul trap. By tuning the confinement of each ion into resonance, we demonstrate classical energy exchange through sympathetic heating and heating rate reduction. The coupling interaction exchange time is extracted to be 22 ms. Practical improvements to the ion-wire-ion system are discussed, with realistic applications to sympathetic cooling of remote ions and more optimistic goals of coherent energy exchange at the single-quantum level. Our ion-wire-ion system establishes a building block for scalable trapped ion quantum computers and provides a tool for quantum communication between qubits of different types.

Advisor: Haeffner, Hartmut
Probing neurophysiological function in the outer retina using chemogenetic manipulation and optogenetic sensors

The retina offers unique insight into synaptic activity in the central nervous system. It is the only part of the central nervous system that can be visualized without advanced imaging or invasive methods. Its highly organized structure has turned it into a main target for neuroscientific studies, and while it has a simplistic anatomical organization its synaptic functions have only been partially elucidated. Zebrafish have been utilized to study vision since they have a cone-rich retina, high acuity vision and they are a convenient model to work with and manipulate genetically. Furthermore, zebrafish can absorb drugs and small molecules directly from their liquid environment thereby facilitating chemical manipulation of their nervous system. For these reasons we have chosen to use zebrafish to generate tools that improve our understanding of retinal synaptic activity in the outer plexiform layer of the retina, and in horizontal cells (HCs) in particular. Five genetically modified strains of zebrafish (4 of which were developed at the Kramer lab) are presented in this dissertation. Two strains have been modified using the introduction of foreign receptors, FaNaC and PSAM-GlyR, allowing controlled and reversible depolarization and hyperpolarization of HCs, respectively. Using these modified strains, we show that by changing the membrane potential of HCs we can manipulate neuronal function upstream, and downstream to the HC synapse. Using three additional strains, we explore the change in pH at different locations in the HC to cone synapse during lateral inhibition. Those locations include the AMPA receptor on HCs, and synaptophysin and the voltage gated calcium channel on the photoreceptor side. By combining our chemogenic tool FaNaC to depolarize HCs, and a genetically introduced pHluorin to detect pH changes, we reaffirm the hypothesis that pH is the signal which mediates lateral inhibition in the outer retina. Using the three pH probes, we show that the change in pH is highly localized nearby photoreceptor voltage-gated calcium channels. In conclusion, while HCs form a wide interconnected network that spans the entire retina, their communication with individual photoreceptors through acidification of the synaptic cleft is spatially constrained. Moreover, slight deviations in HC membrane potential greatly alter their effects on other retinal neurons including photoreceptors, bipolar cells and retinal ganglion cells.

Advisor: Kramer, Richard H
The Labor Plan: Labor, the State and the Labor Code in Chile (1973-2018)

In 1990 Chile transitioned from a military regime led by General Augusto Pinochet to a democratically elected government led by the Coalition of Parties for Democracy, the Concertación, that had successfully opposed his continuation in power. Yet, the dictatorship left many legacies that persisted long after this transition. One crucial heritage was a set of major labor law transformations legislated in 1979 that Pinochet and its author, Labor Minister José Piñera, called the Labor Plan. The Labor Code the Pinochet government bequeathed to its successors was very unfavorable for the labor movement, especially in comparison to the pre-authoritarian legal regime. It was stridently opposed by the labor movement and the incoming Concertación promised “profound changes”, particularly in areas regulating unions, collective bargaining and strikes./nThere were good reasons to believe the prospects for such changes were quite favorable. The labor movement had been a key leader in the opposition movement that led to democratic transition. The movement, and in particular the largest and most important labor organization, the CUT (Central Unitaria de Trabajadores - Unified Workers Central), enjoyed a close relationship of alliance with the Concertación. Indeed, the CUT and the Concertación were both led by leaders from the same two central political parties: the Christian Democratic Party and the Socialist Party. The transition also meant that the institutions of Chile became more open to participation and popular input, and the labor movement was no longer subject to the brutal repression of the dictatorship. Political opportunity theory predicts such an institutional opening should benefit a social movement./nNonetheless, after 20 years of Concertación governments (1990-2010), the Labor Code was left substantially unchanged from that structured by the Labor Plan. Although institutional features of the 1980 Constitution and electoral laws left by the dictatorship as well as unyielding opposition by conservatives played a role in this outcome, this dissertation argues it was the very relationships between the labor movement and the newly ruling political parties and post-transition state that in the end explains this result. A politically incorporated labor movement was unwilling to exert the necessary pressure on allied political actors to dislodge the path of persistence of the Labor Code. So, what is often viewed as an opportunity turned out to obscure a risk of movement containment.

Advisor: Enriquez, Laura
Shaiken, Harley
An AMR All-Speed Projection Algorithm in Proto

In this study, we examine the all-speed projection approach to computational gas dynamicsin the low-Mach limit. This limit is characterized by slow, non-stiff advective flow accompanied by fast, stiff acoustic motions. The all-speed projection method uses a Helmholtz projection to derive redundant equations in the stiff variables: pressure and potential velocity. The resulting equations are discretized using a high-order finite-volume method and integrated in time using a method of lines formulation and an implicit-explicit (IMEX) additive Runge-Kutta (ARK) method. The all-speed projection approach differs from the “zero-Mach” approach of deriving equations of motion in the asymptotic limit as the Mach number becomes small. The zero-Mach strategy yields a differential/algebraic system which is difficult to manage and also explicitly forbids simulation of acoustic waves./nWe introduce adaptive mesh refinement (AMR) to the existing all-speed projection algorithm. In so doing, we needed to address a number of challenges. Previous AMR multigridmethods took advantage of simplifications in order to make use of residual correction multigrid. We have instead used the Full Approximation Scheme (FAS) version of multigrid in our AMR framework. Doing so gives the framework more flexibility, allowing us to solve more complicated operators with inhomogeneous boundary conditions./nPrevious AMR frameworks have been written using C++ for high level abstractions, andwith Fortran used to implement single patch operators. This approach is not productive because Fortran is not an expressive language for representing high-level mathematics and manually programming with low-level abstractions does not scale well with current trends in scientific computing. In light of these observations, we have written our AMR framework mostly from the ground up using Proto, a new C++ embedded domain-specific language for high-performance computing. This study represents the first AMR application written using Proto

Advisor: Colella, Phillip
Papadopoulos, Panayiotis