VictorJuiz/thesis huggingface dataset:
Testing the limits : non-minimal extensions of popular beyond the standard model frameworks

While the Standard Model (SM) represents perhaps the most successful scientific theory ever constructed by humans, it is hardly complete. In the five decades since its inception, a number of intriguing extensions to the SM have been put forward by the physics community which might address questions that the SM leaves unanswered. In this thesis, we consider non-minimal extensions to several of the most popular frameworks for physics beyond the Standard Model (BSM): The Randall-Sundrum model of a warped extra dimension, the introduction of gauged flavor symmetries, and the vector portal/kinetic mixing paradigm for dark matter. Each of these models attempts to address a different unresolved problem within the SM: The Randall-Sundrum model naturally explains the enormous hierarchy between the gravitational and electroweak energy scales (the gauge hierarchy problem), while gauged flavor symmetries attempt to impose a structure on the intricate pattern of fermion masses and mixings present in the Standard Model, and vector portal/kinetic mixing models of dark matter represent a well-motivated subset of models of particle dark matter. In this thesis, we explore directions in which each of these BSM frameworks may be extended beyond their minimal constructions. In Chapter 2, we perform a detailed exploration of brane-localized kinetic terms, which may be added as additional parameters in Randall-Sundrum constructions, analytically identifying the values of these parameters which avoid spacetime instabilities or ghost-like (negative probability) states in the theory. In Chapter 3, we present a model in which a gauged flavor symmetry is incorporated into a Randall-Sundrum framework, and perform a detailed exploration of the resulting distinctive flavor phenomenology. In Chapter 4, we discuss a realization of the vector portal/kinetic mixing dark matter paradigm with a compactified extra dimension, in which the scalar which break the Standard Model electroweak gauge group and the scalar ``dark Higgs'' which breaks the additional dark-sector gauge symmetry proposed by this class of models are localized on opposite 3-branes, naturally eliminating phenomenologically concerning mixing between the dark and SM Higgs fields. In Chapter 5, we present a model which unifies the dark gauge group of vector portal/kinetic mixing models with an SU(3) gauged flavor symmetry, in which an additional fourth generation of matter particles serves as ``portal matter'', facilitating the kinetic mixing required by the dark matter paradigm. We then explore the phenomenology of this construction, noting that some behavior (such as portal matter fields decaying into conventional vector-like fermions) does not emerge in models that include portal matter or a gauged flavor symmetry alone, and will yield unique collider signatures

Keywords: Physics.
Advisor: Hewett JoAnne L.
Graham Peter (Peter Wickelgren)
Peskin Michael Edward
Rizzo Thomas G.
The Antenna’s All the Difference: How Does Primary Cilium Presence Alter Microtubule Organization in Cultured Mammalian Cells?

Cilia are found on most cells in the human body. Cilia are thin, 1-5μm long projections from the cell surface and play a role in cell signaling, mechanosensing, and cell cycle regulation. Centrioles are required for cilia assembly and are also found in almost every human cell. Centrioles must also function as part of the Microtubule Organizing Center (MTOC), or centrosome in animal cells, and are segregated to the mitotic spindle poles. Interestingly, even in mammalian cells that have a cilium in interphase, centrioles lack a cilium when the mitotic spindle forms, raising the question: how does cilium presence affect MTOC activity and spindle formation? To address this question, I used chemical and genetic biology tools to manipulate ciliation states in mammalian cells and observe the effect on properties of the MTOC. First, cilia number was manipulated to determine whether ciliated centrioles are capable of forming functional MTOCs. I found that ciliated MTOCs nucleated microtubules at higher initial quantities than nonciliated centrioles in both monociliated and multiciliated cells. Second, the effect of extended cilium presence was tested by forcing cells with stabilized cilia into mitosis. Mitosis could occur while some form of the cilium was present, but partial disassembly occurred in most cases and may be necessary for proper mitotic progression. These results suggest ciliated centrioles have robust MTOC activity in interphase but the presence of a cilium restricts successful mitosis. Regulation of microtubule organization capacity dictated by cilia presence may be another mechanism of cilia-related cell cycle control, with implications in cancers like medulloblastoma, where persistent signaling through cilium-dependent mechanisms results in abnormal cell proliferation.

Keywords:  Department of Biology
Biology
cell biology
cilia
centrioles
microtubules
mitosis
spindle
Thesis
Advisor: Stearns Tim
Feldman Jessica
The Bell System: A Model of Corporate Innovation and Public Service

The United States is in the midst of a scientific slowdown, with private funds for research and development set to outpace federal investment for the first time since WWII. Federal funding for basic research has been stagnant for the past twenty years, while accompanying legislation has incentivized academics to leave the university and commercialize their work in industry. This coincides with a trend in corporate spending, marked by a focus on development rather than research. As a result, many fear that a persistent drought in US-based innovation is inevitable. In addition, studies show that as science becomes more specialized, research projects become more costly, and in turn scientific and technological progress become more difficult to attain. This comes during a period in which corporate profits and company valuations have reached all-time highs, and yet there is tremendous income inequality, and the public welfare is suffering in various ways. An analysis of the historically successful case of AT&T and their industrial research operation, the Bell Laboratories, illuminates the factors that make consistent innovation, corporate success, and public service possible in the private sector. Moreover, the example of Bell Laboratories displays what political, regulatory and economic conditions enable this combination of private and public interests to prosper. By placing our current challenges in their historical framework, this thesis hopes to shed light on an exit path from our current innovation crisis, and urge people to realize that many aspects of ‘how things are done’ are in fact entirely new and a departure from historical precedents.

Keywords: Science Technology and Society
Bell Laboratories
AT&amp;T
Innovation
Monopoly
Antitrust
Basic Science
Stanford University
Applied Science
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Thesis
Advisor: Pande Vijay
The Benevolent Dictator? Demands for Democracy and Authoritarian Resilience in Oman

Oman saw 50 years of rapid economic development under the autocratic rule of Sultan Qaboos bin Said. The state’s simultaneous advancement and authoritarian resilience puzzled proponents of modernization theory. Even when the Arab Spring triggered waves of protests, the so-called benevolent dictator appeared unshakable. In this work, I identify challenges to authoritarianism and sources of state strength in Oman between 2000 and 2019. First, where did pressures for democratic reforms originate and how did they manifest? Analyzing recent protests, I find that educational cleavages are more relevant for understanding dissent today than the ethno-sectarian divides that historically mobilized critics of the regime. Second, how has state spending related to democratic pressures and authoritarian stability? Evaluating state responses to unrest, I conclude that the Sultanate has relied on oil rents to reward key protest groups. In response to new demands from educated citizens, the state has also made symbolic reforms and increasingly relied on repression. As higher education expands and oil rents falter, democratic demands may reemerge and force the state to either pursue democratization or forgo its benevolence.

Keywords:  Fisher Family Honors Program in Democracy
authoritarianism, democratization, development, Gulf states, oil rents, Oman, popular uprising, rentier state theory, repression, Sultan Qaboos, timocracy
Text
Thesis
Advisor: Blaydes Lisa
The Chatbot Repair Tango

Miscommunication occurs often in conversation. Humans employ various repair strategies to resolve miscommunications that occur in human-to-human speech, in what is called “conversational repair”. However, most chatbots currently in use either do not engage in repair at all, or conduct repair in ways that are, to a human speaker, clumsy and unnatural. This unnatural repair may lead to negative user experiences. This thesis draws on research into users’ experience of bots and conversational repair to explore the types of miscommunication, and possible repair strategies, that may occur between a task-oriented survey chatbot and a user. I find that errors in misunderstanding and repetition are common for medical survey chatbots, but that the first difficult key step for the chatbot is to notice that an error has occurred. From there, I identify repair strategies that are most ‘natural’ in conversation, including previously researched techniques such as “Confirmation”, along with new techniques such as “Simplification” and “Sense-Making”, in the hopes of building chatbots that will be able to have more positive interactions with users. This naturalistic repair, where a patient and the chatbot are able to continue a conversation naturally and fluidly in a way that is metaphorically similar to a tango, is key to improving user experience with chatbots.

Keywords:  Department of Symbolic Systems
Artificial Intelligence
Chatbot
Conversational Agent
Conversational Repair
Human Computer Interaction
Intelligent Assistant
Natural Language Interfaces
Pragmatics
Symbolic Systems
SymSys
Thesis
Advisor: Bernstein Michael
Shrager Jeff
The Community Impact of Post-Earthquake Safety Decisions Based on Damage to Tall Buildings and Elevated Hazard Due to Aftershocks

A key component of community resilience is the ability to recover community functions after an earthquake. Resilience planning focuses on identifying critical functions, setting recovery time targets for various hazard levels, and assessing the gap between the desired and the anticipated performance. These performance assessments should consider all potential disruptions to community functions, such as damage that makes buildings unsafe, damage to equipment and architectural ﬁnishes that makes buildings non-functional, and loss of utility services or transportation access. A recovery-based assessment includes both the initial loss of functionality and the process for restoring it, including stabilizing unsafe buildings and securing the necessary resources to initiate building repairs. A heavily damaged building has an elevated risk of collapse during an aftershock, endangering the occupants in nearby buildings. Post-earthquake safety inspectors evaluate which damaged buildings to red tag and where to set up safety cordons, restricting access to potential fall zones. This dissertation focuses on these access restrictions associated with unsafe buildings.
Post-earthquake decisions regarding which buildings are safe to re-enter are an important part of a community’s recovery process. Unsafe buildings and neighborhoods should be marked as such, alleviating the public’s uncertainty as they take stock of their surroundings. However, these decisions should be made carefully, recognizing their impact on the community. Displacing too many residents through overly conservative red tagging would increase the potential for permanent outmitgration. Businesses in an inaccessible downtown may fail or need to relocate–to the outlying areas or to another city. Therefore, while safety cordons are imperative, their presence should be minimized where feasible, either by building retroﬁts to proactively reduce the likelihood of earthquake damage or by facilitating building inspection and stabilization eﬀorts to remove the cordons as soon as possible. This dissertation proposes tools for quantifying three aspects of access restrictions: the additional community downtime due to safety cordons, the reduced safety of a damaged building, and the elevated risk of building collapse in the presence of aftershocks.

Keywords: Earthquake engineering
Earthquake damage
Earthquake engineering > Research
Earthquake hazard analysis
Text
Technical report
Thesis
The Deterrent Value of U.S. Military Bases in Okinawa: The Case of Futenma

Former U.S. Ambassador to Japan Mike Mansfield once stated: "The U.S.-Japan alliance is the most important bilateral relationship in the world, bar none." It is the primary bilateral security relationship for both the U.S. and Japan. However, since 1996, the Futenma Relocation Issue in Okinawa Prefecture, Japan, has cast a shadow on the alliance since 1996, and the back then agreed on return of Marine Corps Air Station Futenma to Okinawa has yet to be realized. The central government of Japan insists that from a viewpoint of deterrence, the agreed relocation to Henoko in northern Okinawa is the "sole solution". However, there is a contradicting statement by former Prime Minister of Japan Yukio Hatoyama (DPJ), stating that deterrence was “just a pretext” in this context. The aim of this thesis is to shed light on the question of which of these statements is right. The main research question is in how far Okinawa and the Futenma base contribute to deterrence in the context of the U.S.-Japan alliance. Employing the method of qualitative text analysis drawing on official statements on the research question from both the Japanese and the U.S. side, and discussing deterrence theory in the context of the alliance, this thesis concludes that the central government of Japan oversimplifies the complex realities of deterrence in the context of the U.S.-Japan alliance to justify the current Futenma relocation plan to Henoko in the face of the Japanese public. Resistance against the current relocation plan is particularly strong in Okinawa in both the public and the governmental spheres. The finding is that official statements on Okinawa and deterrence are scarce and vague, which begs the question of the substance of any statement on the importance of Futenma for deterrence purposes.

Keywords:  Stanford Global Studies
Stanford University
Center for East Asian Studies
U.S.-Japan alliance
Futenma relocation issue
Okinawa
deterrence
extended deterrence
Thesis
Advisor: Sneider Daniel
The Donut Effect: How work-from-home impacts migration patterns and real estate markets

I measure the effect of Covid-19 on migration flows and real estate markets within and across US cities. Using near real-time data from Zillow and the US Postal Service, I establish three key results. First, both households and businesses reallocate away from zip codes that are close to a city’s center, have a high share of residents who can work-from-home (WFH), or have high density. Second, this reallocation occurs across many cities when measured with rental rates, but only holds for “superstar” cities when measured through property prices. Third, the within-metro reallocation from city centers to their suburbs is stronger than the between-metro reallocation from dense metros to sparse metros. I rationalize these findings by building a simple spatial equilibrium model where hybrid WFH, as opposed to full-time WFH, generates qualitative predictions that match the empirical patterns. My results suggest that Covid- induced WFH has led to a persistent shift in the spatial allocation of labor.

Keywords: Stanford University Department of Economics
COVID
working-from-home
real-estate
migration
future-of-work
Thesis
Advisor: Bloom Nicholas
Klenow Pete
The effect of a large-scale water, sanitation, and hygiene intervention in Bangladesh on knowledge, behavior, and health: findings from an endline evaluation of a matched-pair cluster-controlled trial

Background: Diarrhea is a leading cause of child death in Bangladesh, where water quality, sanitation, and hygiene (WASH) technology and behavior uptake is low. From 2007 to 2012, the Sanitation, Hygiene Education, and Water Supply in Bangladesh Programme (SHEWA-B) aimed to improve WASH practices among 20 million rural residents through community hygiene promoters (CHPs). In 2010, the team implemented changes to improve the intervention, including simplifying messages and incentivizing CHP performance. This study evaluates the impact of SHEWA-B on knowledge, behavior, and childhood diarrhea outcomes after midline changes were applied.
Methods: This study included repeated cross-sectional surveys with embedded matched cohorts in intervention and control clusters. Cross-sectional surveys and structured observations at baseline, midline, and endline assessed the availability of WASH technology, caregiver knowledge, and behavior. Fieldworkers collected longitudinal monthly health data in a subset of control and intervention households to determine prevalence of diarrhea.
Results: Of 5091 households surveyed, participants residing in intervention clusters showed minimal improvements in knowledge, reported behavior, or use of WASH technology compared to the control clusters. Comparing endline to baseline, intervention clusters showed a greater increase in knowledge that washing hands before preparing food is important. Comparing endline to midline, intervention clusters showed a greater increase in use of improved latrines, but there were no differences in changes to any other indicators. During structured observations, intervention households improved more than control households at handwashing before preparing food and after cleaning a baby’s anus when comparing endline to baseline, but these changes were not seen when comparing endline to midline. Before midline changes were made, the prevalence of diarrhea among children remained similar in the intervention group (10.2%) and control group (10.0%). After midline changes were made, the prevalence continued to remain similar within each group (8.8% in intervention, 11.7% in control). The intervention clusters showed no improvement in diarrhea over time compared to the control.
Conclusion: SHEWA-B’s community-based WASH promotion did not yield the intended impact on knowledge, behavior, or health. This study shows that even after changes were implemented midway through the intervention, the intervention impact was limited. Greater priority should be given to approaches that have demonstrated effectiveness and more evaluations should be undertaken to improve large-scale programs.

Keywords: Bangladesh
Water, sanitation, and hygiene
Community health workers
Text
Thesis
Advisor: Luby Stephen
Benjamin-Chung Jade
The Effect of Multiple Voices: The Discourse of an Artemisia Desertorum Allergy Epidemic in Yulin, China

Ever since the “suffering subject” has become the center of anthropological effort starting in the 1990s and going forward (Joel Robbins, 2014), the question of suffering has been examined using two theoretical viewpoints, namely, “those of endurance and of agency” (Marja-Liisa Honkasalo, 2009). For the “endurance” framework, suffering is viewed as “an existential experience at the border of human meaning making,” which begets the questions of “how to endure, how to suffer?” In contrast, the dimension of “agency” explores “how to avoid or how or diminish the emotion.” Regarding the issue of “agency,” many scholars have examined the agency of sufferers in terms of their ability to act on their suffering rather than simply remaining a passive subject experiencing pain. Avoiding the portrayal of sufferers as passive subjects also means amplifying their voices. However, one of the potentially most problematic features of such scholarship is that little attention is given to the potentially limited effect of sufferer agency in easing their pain. When sufferers can finally talk and act, to what extent are others actually listening and truly understanding them? What if sufferers’ voices and their actions against their suffering do not produce the optimal effect, and these sufferers have to continually endure their pain? In such situations, how can we amplify sufferers’ voices and thereby reinforce their actions against their painful experience? In taking the artemisia ordosica allergy in Yulin, China, as a case study, this paper shows the impasse that local sufferers face when their voices are not sufficient enough to stimulate the attention they need both socially and culturally, thereby leaving them no choice but to continue enduring their pain. In such situations where the boundaries between “agency” and “endurance” as both relate to “suffering” dissolve, secondary voices need to join in and support these sufferers and help them overcome their predicament. By engaging with ethnographic interviews with local sufferers in Yulin, medical anthropology theories, and modern Chinese literature, this research explores the challenges of speaking up for sufferers as non-sufferers and the corresponding solutions in order to demonstrate how secondhand storytelling have the potential to garner more support for sufferers and inspire further efforts to resolve outstanding issues. Ultimately, this paper not only aims to encourage allergy sufferers to continue speaking about their experiences, but also to encourage those without allergies to speak out on their behalf as well, thereby establishing a strong solidarity of caring and greater engagement with a wider array of potential problem-solvers in the search for solutions that work.

Keywords:  Stanford Global Studies
Artemisia Desertorum Allergy
Suffering Subject
Second-hand Storytelling
Medical Humanities
Stanford Global Studies
East Asian Studies
Text
Thesis
Advisor: Wang Ban
The Emergence of Cyber Defense and Governance Structures in the Middle East

What motivates Middle Eastern nations to develop the cybersecurity governance agencies that protect from malicious cyber activity? As the world has watched major cyber powers such as China, Russia and the United States emerge, the Middle East -- a region often at the forefront of conversations on conventional military conflict -- has been broadly neglected in the scholarship on cyber warfare. This is a consequential omission as cyber conflict is on the rise between Middle Eastern states. Analysis of an original data set of over 50 significant cyber incidents since 2007 shows that the biggest perpetrators of malicious cyber activity against Middle Eastern states are state actors within the region, not extra-regional states, third-party hacking groups, terrorist organizations and political organizations. Moreover, this malicious cyber activity has had two major waves of increase that align with both the Arab Spring and the Persian Gulf Crisis. The growing threat of regional cyber conflict suggests that Middle Eastern nations have been motivated to develop cyber defense structures in response to a growing regional threat of malicious cyber activity.

Keywords:  Center for International Security and Cooperation
cybersecurity
Middle East
cyber conflict
cyber defense
cyber attack
CISAC
Thesis
Advisor: McMaster Lt. Gen. H.R.
Blaydes Lisa