VictorJuiz/thesis huggingface dataset:
Bioinspired self-assembly of microscale surface-tension based systems [electronic resource]
Keywords: Materials Science and Engineering.

Fluid-fluid interfaces represent a unique environment which drives the self-assembly of systems such as colloids and Janus particles of varying shapes and functionality. Despite a large body of work on interfacial self-assembly, there remains a huge amount of design space which has yet to be explored. In this work, I present experimental and simulated biomimetic interfacial self-assembly schemes that derive their function from the controlled interplay of capillary forces and biologically inspired structure. The goal of these schemes is to leverage lessons learned from the self-assembly found in cellular biology, and translate them into complex assembly at microscale fluid interfaces. The beginning chapters focus on using the framework of clathrin-mediated endocytosis to create microfabricated, micron-scale artificial clathrin mimics. These mimics are able to recruit to a fluid interface, self-assemble into organized networks, and drive the budding of a fluid interface under external stimulation. This behavior is analogous to the process of nanoscale clathrin-mediated endocytosis but works on the microscale using surface-tension driven physics. Particle curvature is determined to be the most important parameter in governing the behavior of these particles, leading to a reduction in nonspecific aggregation and control over network organization. The later chapters draw further inspiration from protein-protein assembly to model methods for the selective self-assembly of interfacial microscale particles. The first method is the application of structural "pockets" to control the self-assembly of particles in a "lock-and-key" type mechanism. The second method is control over the broader kinetic assembly landscape for these particles by altering their gross structure and tuning their capillary interactions. The final methods draw inspiration from allosteric proteins, demonstrating the concept of "hidden" self-assembly sites and their activation by mechanical buckling in microscale particles. Taken together, these methods demonstrate strategies in which the interplay of capillary forces and physical structure can be leveraged to translate biological self-assembly motifs to the assembly of inorganic particles at fluid interfaces.
Biosocial approaches to epidemic disease in sub-Saharan Africa [electronic resource]
Keywords: Anthropology.

The included seven articles, based on biosocial approaches to epidemic disease in sub-Saharan Africa, trace instances of how large-scale social forces become embodied as pathology. Through a range of methods, including ethnography, network modelling, air sampling, regressions, and surveys, each article attempts to resocialize our understanding of disease distribution and outcomes, with the goal of producing a critically applied medical anthropology.
Blood and bone [electronic resource] : families, forensic teams, and the poetics of exhuming the dead
Keywords: Anthropology.

In the past thirty years, exhumation of mass graves after political violence has become a human rights imperative. Based on fieldwork in Argentina and Guatemala, this dissertation offers an ethnographic tracing and historical meditation on forensic exhumation. It follows the efforts of forensic teams to exhume, identify and return the remains of missing people to their families and considers the experiences of families as this process unfolds. This ethnographic account is juxtaposed with histories of the dead, from Vesalius' revival of dissection in the sixteenth century, to Victorian anatomy museums, to twenty-first century forensic fiction. Ethnographic and historical accounts reveal exhumation to be more than a purely technical, scientific or political practice. The rapid rise of exhumation that began at the end of the twentieth century is not solely due to changing norms of transitional justice, advances in DNA identification or new efforts of humanitarian care, although such factors play important roles. Rather, understanding the intense interest exerted by forensic intervention requires a "poetics of exhumation" that considers the symbolic power of the corpse, its secular-sacred afterlives, and how science and spectacle have been entangled in forensic practice from its beginnings.
Boundary fibration structures and quasi-homogeneous geometries [electronic resource]
Keywords: Mathematics.

In this thesis we extend work by Mazzeo on conformally compact manifolds to a class of manifolds with quasi-homogeneous geometries, which we call kappa-manifolds. Our results show that there are complete noncompact manifolds of negative curvature, that have 0 in the essential spectrum for the Hodge Laplacian on forms, and this applies in a range of degrees centered at the middle degree. As is typical for boundary fibration structures our methods give much more, namely we provide a general framework to study elliptic partial differential operators on kappa-manifolds based on microlocal methods. We construct a calculus of pseudodifferential operators on the manifold, and give precise conditions for the existence of a parametrix for elliptic differential operators in this calculus. This work takes up the bulk of the thesis. We then apply this to the spectral theory of the Hodge Laplacian on a kappa-manifold. This step requires detailed analysis of the Hodge Laplacian on a simpler model space, which in turn requires detailed study of a system of ordinary differential equations.
Brain-inspired computing with resistive non-volatile memories [electronic resource]
Keywords: Electrical Engineering.

Training of large scale neural networks require thousands of processors, massive amounts of off-chip memory, and kilowatts of power to complete within a reasonable amount of time. The bulk of this power is consumed in moving data between the fast multicore processors and off-chip memory. After trained in backend infrastructure, model parameters can be deployed on mobile devices for inference tasks possibly combined with further training for local customization. However, off-chip memory accesses also dominate required power in mobile devices, limiting the size and scale of neural network models deployed on mobile devices by the amount of on-chip memory available, which is limited due to the large area of SRAM. For both training and inference tasks, resistive switching memories offer a compact, scalable and low power alternative that permits on-chip co-located processing and memory in fine-grain distributed parallel architecture. In this dissertation, approaches to utilizing resistive memories in analog fashion as synaptic weights in neural networks are described and analyzed. First, proof-of-concept demonstrations of training different types of neural networks with noisy energy efficient analog weight updates are presented using fabricated resistive memory devices. Effects of device variation on energy efficiency and training accuracy are measured. Then, using experimentally validated compact model of metal-oxide resistive switching memory, effects of device non-idealities on training accuracy as well as energy efficiency is studied using a single-layer neural network (Restricted Boltzmann Machine) as a case study. Requirements for resistive memories as well as programming schemes for mitigating the effects of device non-idealities are elucidated. An architecture with resistive memories optimized for inference tasks, Efficient Resistive Neural Inference Engine, is also presented. This architecture combines algorithm and hardware co-optimizations by using pruning, quantization and noise injection on algorithm level, and low power low-precision analog and digital circuits on circuit level. Architecture is then benchmarked against fully digital CMOS system. Resistive technology outperforms digital CMOS by ~8× if a cell can store a weight with ~6-bit precision and if activations can tolerate 1 or 2-bit precision. If a cell cannot store more than 2 bits or if activations require > 3-bit precision, benefits diminish significantly.
Bridging Worlds: The Role of An Affinity Group in How Students of Color Negotiate Race and Identity in An Elite Prep School
Keywords: elite prep schools
race
class
identity
affinity groups
Thesis

In my research, I explored the experiences of students of color in an elite prep school and the role of an affinity group in their experiences through in-depth interviews with eleven individuals of color who attended an elite prep school in the Midwest. Through these conversations, I examined how students of color perceived and related to the school, the affinity group, and their racial identity. My analysis revealed that, first, the participants conceived of the school as a wealthy, white education environment where they experienced both racial and class marginalization. Second, in such an environment, the participants found the self-affirming and community-building functions of the affinity group for students of color to be vital. On the other hand, the group was also perceived to be a group for black students that harbored resentment towards white students. Finally, the participants’ diverse racial experiences reveal the ways in which the student of color category is not as straightforward or racially monolithic as it appears to be. My research thus confirms the major social, psychological, and cultural issues the literature has found to be common to students of color in elite, white educational elite. It also contributes to findings regarding the importance of creating race-based support spaces reserved for students with marginalized racial identities – and the crucial limitations of these initiatives.
Brownian modeling of queues [electronic resource] : rates of convergence to equilibrium, departure variability, and large deviations
Keywords: Management Science and Engineering.

This dissertation is divided into two parts, the first of which revolves around rates of convergence to equilibrium for single-server queues (consisting of Chapters 2 and 3) and the second of which revolves around asymptotic variability and large deviations for departure processes in single-server queues (consisting of Chapters 4 and 5). Throughout the thesis, significant emphasis is placed on the Brownian modeling of queues, using reflected Brownian motion (RBM) both as a direct modeling tool as well as vehicle through which to obtain insights into pre-limit queueing behavior.
Business groups and internationalization [electronic resource]
Keywords: Management Science and Engineering.

Prior research on how firms in developing countries undergo internationalization has been limited. However, as more firms have successfully internationalized in recent years, there is a need for better understanding why, how, and where they choose to internationalize. This dissertation examines the internationalization of business groups in developing countries and the importance of institutional settings. Based on this examination, this dissertation advances the thesis that business groups have two paths that need to be balanced in order for business groups to thrive. The first path is to enter other institutionally close developing countries by exploiting the firm's existing resources and know-how. The second path is to enter institutionally close developed countries to acquire technological sophistication and improve their organizational learning capabilities through long-term investments. This dual approach enables business groups to survive economic downturns and outperform established industry leaders as seen during the recent financial crisis. In support of this thesis, I incorporate several prior theories on the liability of foreignness and institutional theory; investigate the role of culture in the internationalization of business groups; and analyze two in-depth case studies. This multi-pronged approach provides a framework for scholars to better understand the internationalization and associated strategic motives. This study contributes to the theory of internationalization and to the ongoing research of culture in the field of international business. Lastly, this study makes valuable recommendations to managers and government policymakers on how to optimize the resources and capabilities of business groups to support their domestic markets.
The butterfly effect in solvable quantum many-body systems [electronic resource]
Keywords: Physics.

The butterfly effect, as an icon for the chaotic dynamics, refers to the exponential sensitivity on the initial conditions. This phenomenon is common in daily life, e.g. it explains the difficulty of long time weather reports. For physicists, the idea of the chaotic dynamics helps to understand the ergodicity of a classical complex system and therefore is essential for the statistical mechanics and thermodynamics. In the microscopic many-body systems governed by quantum mechanics, the chaotic dynamics is also expected to be generic and ultimately helpful for the understanding of the quantum thermalization. What I will show in this dissertation is that the quantum butterfly effect could also provide precise information about the nontrivial properties of the many-body interacting systems, such as thermal transport and topological properties. I will employ two classes of solvable models: the Sachdev-Ye-Kitaev model in high dimensions and the rational conformal field theories in two dimensions to explicitly present the unexpected connection between the butterfly effect and other aspects of the model.
Campaign Effects On The Stock Market: The Case Of The 2016 Election
Keywords:  Department of Communication
Stock Market Indicators
Election
Campaigns
2016 presidential elections
Stanford University Department of Communication
Donald Trump 1946-
Thesis

The 2016 presidential election displayed at least one candidate who used strong enough campaign rhetoric about potential economic policy change that may have affected market wide stock market indicators. Trump’s candidacy represented a lot of unknowns. As an unknown candidate with unknown economic policies, it can be expected that increases in his polling numbers – widely covered in the media – will depress the value of the stock market and vice- versa. In the context of the 2016 presidential election, I anticipate that Donald Trump’s use of extreme rhetoric about economic policy and his popularity through the polls may have been associated with immediate effects on market wide economic indicators.
Capturing dynamic correlation with variational explicitly correlated wavefunctions [electronic resource]
Keywords: Chemistry.

In this dissertation, we describe, implement, and test wavefunctions that describe short-range, so called dynamic correlation effects through the use of explicitly correlated geminal pair functions. We present both a single-configuration explicitly correlated analogue of a Hartree-Fock wavefunction, and a multi- configurational variant, a Geminal-augmented Complete Active Space Self Consistent Field method. These methods are designed to efficiently include dynamic correlation effects during variational optimization of the wavefunction, rather than resorting to a post hoc perturbation description. We test both methods on a number of model systems and show that the geminal-augmented wavefunction is capable of describing short-range correlation effects. In addition, we present a fully exact implementation of the algorithms necessary to evaluate the many-electron integrals that arise in explicitly correlated wavefunctions.
Carbon chemistry during the late summer in the Ross Sea, Antarctica [electronic resource]
Keywords: Earth System Science.

The Ross Sea is the most biologically productive region in the Southern Ocean and is a large atmospheric CO2 sink. In addition, the Ross Sea is vulnerable to anthropogenic ocean acidication. This dissertation focuses on carbon data from the first biogeochemical process cruise to the Ross Sea during the late summer. Chapter 1 presents around 1700 surface water total alkalinity (TA) measurements from the Ross Sea and Southern Ocean. In addition, I use a TA-salinity relationship and historical pCO2 measurements to estimate the carbonate saturation state of surface waters in the Ross Sea during the winter. Results from this analysis suggest that the Ross Sea is not likely to become undersaturated with respect to aragonite from anthropogenic ocean acidication until the year 2070. Chapter 2 provides evidence for substantial net community production (NCP) during the late summer in Terra Nova Bay in the western Ross Sea. This is the first study to document substantial late season NCP in Antarctic shelf waters, which is associated with green frazil ice from algal accumulation. It is hypothesized that strong katabatic winds in Terra Nova Bay prevents the formation of more opaque ice and results in circulation patterns that concentrate algae and frazil ice into wind-rows. The buoyant properties of the frazil ice may keep the algae near the surface for longer periods of time where light is more abundant while deepening mixed layers may supply growth limiting micronutrients from below. This late season NCP was rapidly exported to below 200 m and kept surface pCO2 low even though the mixed layer deepened and entrained CO2-enriched water from below. In Chapter 3, I examine the impact of late season NCP on air-to-sea CO2 flux rates. I calculate CO2 flux rates between the atmosphere and ocean using pCO2 and wind speed data from 20 cruises in the Ross Sea (2003-2013), including from the late summer cruise. In addition, annual flux rates are estimated from nutrient budgets from the late summer cruise. The results suggest that the Ross Sea as a whole is a lesser atmospheric CO2 sink than previously reported. Terra Nova Bay is the exception, with extraordinary air-to-sea CO2 flux rates there during the late summer caused by the unique coupling of strong katabatic winds and low surface pCO2 values (from late season NCP). Chapter 4 builds on the previous chapters by using daily 500-m resolution satellite imagery (February/March, 2003-2017) to identify green frazil ice hot spots and examine interannual variability in green frazil ice extent. I find that green frazil ice is concentrated in 11 of the 13 major sea ice production polynyas, with the greenest frazil ice in Terra Nova Bay and Cape Darnley polynyas. The results suggest that although there is substantial unexplained interannual variability, green frazil ice on average covers over 300,000 square kilometers during March. Together these chapters provide important insights into carbon cycling on Antarctic continental shelves.
Causes and consequences of news media content [electronic resource]
Keywords: Political Science.

The nature of the news media's political influence depends crucially on the type and volume of political information that citizens encounter when they read, listen and watch the news. This dissertation examines the causes and consequences of this political coverage. The first paper introduces a new empirical approach to test two long-standing accounts of media bias in the mainstream press. Studying election predictions offered by several specialized media outlets that receive a prominent place in news coverage of congressional elections, I find evidence of an institutional bias in which media ratings are overly favorable towards the electoral prospects of incumbent politicians relative to their challengers. At the same time, this approach offers no evidence of a partisan bias in which these outlets favor candidates from one political party at the expense of the other. The second paper examines the consequences of the political information environment for the public's reliance on party labels to evaluate politicians. Using a doubly-randomized conjoint experiment and an observational study of voting in congressional elections, I show that greater amounts of information reduce the role of partisanship in candidate choice. These findings challenge competing claims that partisan cues inhibit responsiveness to such a degree that voters fail to use other information or that high-information environments increase voter reliance on partisanship. The third paper explores the consequences of a recent change in the local media environment. Newspapers produce political coverage read by a large number of readers, yet they do so with 30% fewer reporters and editors than a decade ago. This rapid decline is thought to pose a threat to the provision of political news. This paper employs two new sources of data to directly measure changes in newspaper staffing and examine their effect on newspapers' attention to local, state and national politics. I show that declines in staffing lead to less political coverage, an effect that is particularly pronounced for local political news. Given that newspapers serve as the primary source of original reporting on local politics, this suggests staffing declines have broad consequences for the local media environment.
Cell fate control by spatiotemporally regulated signaling pathways [electronic resource]
Keywords: Biochemistry.

Cells must coordinate their behaviors to occur at the correct time and place. Asymmetric cell division, which underlies cellular differentiation across the kingdoms of life, presents a major coordination challenge. Cell fate signaling proteins must respond to cell cycle progression cues, interpreting these signals in the context of their subcellular location. We studied how the bacterium Caulobacter crescentus, a model organism for the study of asymmetric division, coordinates cell polarity, differentiation, and DNA replication. Caulobacter couples these processes through spatiotemporal control of the phosphorylation state of a master regulator, CtrA. Beginning with an investigation of the ordered assembly of a G1/S signaling complex that downregulates the level of active CtrA~P, we find that disruptions to the expression level or localization of this G1/S complex creates major cell polarity aberrations. We further investigate how CtrA becomes reactivated by a multi-sensor histidine kinase, CckA, in late S-phase. CckA switches between kinase and phosphatase activity towards CtrA in response to multiple spatially controlled upstream signals. CckA detects these signals, which include its own membrane surface density, the second messenger c-di-GMP, and a pseudokinase, DivL, through distinct sensory PAS domains. Our study of CckA's signal transduction illustrates how multi-sensor kinases enable complex bacterial decision making based on an array of spatially and temporally oscillating inputs.