VictorJuiz/thesis huggingface dataset:
The Effect of Inflammation and Inhibition on the Coding of Cutaneous Temperature in the Spinal Cord
Keywords: Chen, Xiaoke
Biology, 2016
Biology
Neurobiology
Pain
Inflammation
Inhibition
Thesis

Hyperalgesia and allodynia, two frequent symptoms of persistent pain, arise from either heightening the sensitivity of previous painful stimuli or making innocuous stimuli noxious, respectively. Understanding the neural circuitry mechanism underlying this persistent pain is of significant scientific and clinical interest. At the periphery, application of pro-inflammatory compounds lead to exaggerated responses to stimuli; while in the central nervous system, pro-inflammatory compounds suppress the inhibitory gate and exaggerate the responses to stimuli as well. Previous literature has shown that there are specific neural substrates that contribute to the gating of pain, but these studies rely on genetic strategies to ablate a large population of neurons, thereby creating a lack of specificity. We combined a novel in vivo two-photon spinal cord imaging preparation with the formalin injection model of persistent pain to systematically examine spinal neurons’ responses to thermal stimuli in a large population of neurons with single cell resolution. This platform allowed us to identify the specific populations of neurons that are modulated by pain and characterize their behaviors. We show that formalin produces warmth allodynia while decreasing the response to cold stimuli preferentially in broadly tuned cells. This increase in response to warmth and decrease in response to cold is partially mediated by the circuitry crosstalk of TRPV1 DRG inputs. Finally, we show that the application of glycine receptor antagonist, strychnine, and GABAA receptor antagonist, bicuculline, lead to an increase in neuronal response to temperature stimulation suggesting a critical role of the inhibitory circuitry in gating of pain.
The Lines We Draw: Nationalism and Border Creation at Sèvres and Lausanne
Keywords: Sèvres
Lausanne
borders
nationalism
state creation
International Relations Honors Program
International Relations
Thesis

This thesis describes the multi-faceted political modernization of the Middle Eastern Region and the transformation of the Ottoman Empire into a system of modern states. To that end, this thesis examines two cases: the treaties of Sèvres (1920) and Lausanne (1923) to understand why some groups garnered statehood rather than others in the succession of treaties both during and after the First World War. It ultimately finds that the groups that were most nationalized were able to claim the most territory in each of these treaties, despite other geopolitical pressures. In this liminal period, national movements could actively argue a state into being.
The Perceived Influence of the Leland Scholars Program on First-Generation Students’ Academic and Social Experiences in STEM and at Stanford
Keywords: First-Generation
summer bridge program
summer transition program
Leland Scholars Program
STEM
science education
educational equity
Thesis

Objective: In this study, I investigated the perceived influence of the Leland Scholars Program on first-generation students’ academic and social experiences in science, technology, engineering, and math (STEM) at a private, research-intensive, and highly selective university. The Leland Scholars Program is a summer program intended to facilitate the college transition for first- generation, low-income, and minority students with a self-declared interest in studying STEM.
Method: Ten Leland Scholars Program participants were interviewed, and they responded to questions about their experiences and perceptions regarding STEM, Stanford and the Leland Scholars Program. Interviews was transcribed, coded, and reviewed for themes that were commonly expressed by interviewees.
Results: Participants felt that their experiences at Stanford were positive and negative, much like a “roller-coaster.” Furthermore, participants expressed feeling anxious and procrastinating in response to the challenging coursework and exams they encountered in STEM courses. Participants also felt intimidated by the university and their continuing-generation peers. Despite questioning their sense of belonging and the real-world applications of their coursework in STEM, students referenced their desire to help their home communities as an important reason for persisting in STEM. Students perceived the summer chemistry course, interpersonal connections with faculty and upperclassmen, and the academic seminar as the most positive components of the Leland Scholars Program.
Conclusion: Summer bridge programs may be used to attenuate the achievement gap between first-generation and continuing-generation students pursuing baccalaureate degrees in STEM in the United States, but additional interventions are necessary to fully address this educational disparity.
The Phantom Jewess: Depictions of Jewish Women in Medieval English Literature
Keywords:  Department of English
Stanford University
Stanford University Department of English
Department of English
medieval
Jews
Jewess
medieval Jew
Chaucer
Prioress's Tale
exempla
women
absence
Other
Thesis

This thesis examines depictions of Jewish females in medieval English literature (1200-1400). It is divided into three main parts: first, I examine the historical background leading to the expulsion of Jews from England in 1290. What roles did women play in society? What roles did Jews play? And, the intersection of the former, what roles did Jewish women hold? The second part involves close reading three exempla, and the third analyzing Chaucer's Prioress's Tale, where, surprisingly, there are no Jewish women literally present in the text. Generally speaking, medieval Jewish women lied at the cross section of two minorities, of two typically despised and mistreated groups in the developing Christian society: women and Jews. Women were seen as inferior beings in a heavily patriarchal society and Jews as devil's conspirators; my initial hypothesis, thus, was that Jewish women would be doubly scorned in the literature. In fact, my findings suggest a more nuanced portrayal of Jewesses. In exempla, they are portrayed in three main ways: as seductresses with the potential to convert (typically unlike Jewish males), as pitiful mothers, and as mediators between the Christian and Jewish communities. In The Prioress's Tale, the removal of the Jewess solidifies the position of Jews as uprooted beings and highlights the importance of the role of the Christian mother, who symbolizes the transition from old to new. This method of exclusion is effective in furthering the understanding of Jews as Other and thus in aiding the development of what I will call the Christian project. The overarching problematic arising both from exempla and from the work of Chaucer is that the stereotyped Jewess replaces the actual. The fictional Jewess becomes so embedded in the cultural fabric that it becomes nearly impossible to remove the spiteful notions concerning her persona without corrupting the entire system upon which the English Christian society is founded.
The Political Geography of Upper Mesopotamia: How Al-Jazira Became Home to the Islamic State
Keywords: Al-Jazira
Islamic State
ISIS
ISIL
safe haven
tribe
tribal structure
upper mesopotamia
Center for International Security and Cooperation
The Freeman Spogli Institute for International Studies
Stanford University
Thesis

This project analyzes the unique geopolitical history of the Al-Jazira region of Iraq and Syria, an area better known today as the safe haven of the Islamic State. Nested between and immediately around the Tigris and Euphrates Rivers of Upper Mesopotamia, the Al-Jazira region has a physical and human geography that encourages the importance of tribal structures. Al-Jazira is also distant from capital cities and the major urban centers associated with governing states, hindering direct political control of the area. The unique governance challenges associated with the Al-Jazira region have major strategic implications for defeating the Islamic State. Using the historical analysis of this project as a guide, I offer two different scenarios associated with the governance of this region by the Islamic State. The first suggests that the communities of Al-Jazira will be unable to generate resistance to the Islamic State because the citizens and social groups in this region lack experience with organized resistance. In this scenario, the Islamic State maintains control of Al-Jazira in the absence of external intervention. The second scenario suggests that because of high levels of social solidarity across and within the tribes of Al-Jazira, the Islamic State, like other political units seeking to exercise sovereignty over the region, will fail in its attempts to politically subordinate the existing tribal structure. In this scenario, once the tribal leadership of key tribes in the area turn against the Islamic State, internal resistance will lead to overthrow of the Islamic State without the need for external intervention.
The presence and mass of nearby massive halos predict galaxy quenching
Keywords:  Department of Physics
galaxy formation
structure
cosmology
statistics
Thesis

We present a novel method for populating galaxy specific star formation rates (sSFR). Galaxy models with assembly bias reproduce color-dependent clustering. Typically, merger trees are used for keeping track of color, but they are both computationally expensive and sensitive to resolution. Using machine learning, we compare the effectiveness of different local density proxies in predicting sSFR. We apply the method to a variety of catalogs with different galaxy formation models. To verify the predicted colors, we look at a number of halo statistics which are assembly bias influenced. We find that presence (mass of and distance to) of nearby massive halos is the most effective density proxy. In particular, we examine RHill which has been shown to relate to halo formation histories. Because the method relies on halo properties, it is particularly useful for populating color in low-resolution simulations.
The Role of Brain Oscillations in Memory Processing in Siberian Hamsters
Keywords:  Department of Biology
Biology
Neuroscience
Circadian Rhythms
EEG
Theta
Thesis

This study investigated the role of the suprachiasmatic nucleus (SCN) in the expression of hippocampal theta rhythms by electroencephalographic (EEG) recordings in freely behaving Siberian hamsters (Phodopus sungorus) in response to novel object exploration. The SCNs of these animals were made circadian-arrhythmic in one of two ways. The first way involved a disruptive phase shift (DPS) protocol that induced arrhythmia while leaving the animals neurologically and genetically intact. The DPS protocol consisted of administering a phase-advancing light signal on one night and a phase-delaying signal on the following night. The second method made hamsters arrhythmic through surgical ablation of the SCN (SCNx). Hippocampal theta rhythms are necessary for encoding spatial information and for providing spatiotemporal information to hippocampal place cell assemblies. Because DPS-arrhythmic Siberian hamsters exhibit substantial impairments in hippocampal-dependent memory tests, we recorded EEG signals during an object exploration task and investigated how certain properties of their EEG signals differed from SCNx and entrained (ENT) animals. Deficits in cognitive performance caused by disrupted circadian timing have become a growing concern among health care professionals. Additionally, identifying EEG markers of impaired memory may benefit clinicians as an early non-invasive screening technique to identify early stages of mild cognitive impairment (MCI) or Alzheimer’s.
The Role of CapZ Actin-Capping Protein in T Cell Motility and Activation
Keywords:  Department of Biology
Biology
T Cells
Immunology
Microscopy
Actin-capping proteins
CapZ
Thesis

T cells are crucial for the immune system to mount an adequate defense against foreign invasion. To be activated against a pathogen, antigen-presenting cells come into intimate contact with naive T cells and form the immune synapse (IS), a structure that facilitates MHC-TCR binding and exchange of signaling molecules. Actin-capping proteins modulate changes to the cytoskeleton, a process that allows for movement toward APCs and formation of the IS, although their role in T cells is largely understudied. We report here a study focused on understanding the dynamics of one of these capping proteins, CapZ, in regulating T cell movement and activation, both crucial processes in T cell defense against pathogen. Using gene-cloning techniques, we constructed a fluorescent CapZ fusion protein as well as an shRNA knockdown, and successfully expressed them in T cells using retroviral transduction. Using confocal microscopy, we show that CapZ localizes to the leading edge of motile T cells, whereas silencing of CapZ resulted in cells that moved faster, farther, and straighter. Examining formation of the IS with APCs, we found that CapZ localizes to the interface of the IS, and loss of CapZ in T cells results in cells that can form larger synapses with APCs. Further studies of the mechanism of CapZ in T cell activation may provide new, interesting approaches for manipulation of T cells in fighting infections and cancerous cells.
The Role of CD47 and PD-L1 in Tumor Regression upon MYC Inactivation in MYC-induced Tumors
Keywords:  Department of Biology
Biology
Oncology
MYC
Oncogene Addiction
Immunology
Thesis

The MYC oncogene, which is overexpressed in many human cancers, is a transcription factor that regulates cell proliferation, growth, differentiation, and apoptosis. Upon MYC inactivation in MYC-driven tumors, an intact immune system is essential for sustained tumor regression, but the role of specific immune effectors is unclear. Our lab has recently found that MYC suppression results in decreased gene and protein expression of the immunoinhibitory molecules CD47 and PD-L1 in a conditional mouse model system for MYC-induced tumors. CD47 and PD-L1 are critical to the mechanism by which tumors evade the host immune system. Specifically, we show that when MYC is inactivated in tumors with enforced CD47 or PD-L1 expression, the host immune response is suppressed, preventing sustained tumor regression and leading to a faster rate of relapse. Through immunohistochemistry, we further show that enforced expression of CD47 and PD-L1 prevents angiogenic shutdown, blocks senescence, and inhibits recruitment of immune cells after MYC inactivation. Therefore, the data presented here suggests that MYC appears to initiate and maintain tumorigenesis in part through the increased expression of CD47 and PD-L1.
The Role of Ethics in the Design and Regulation of Autonomous Vehicles
Keywords: Vienna Harvey
Stanford University
Program in Science Technology and Society
STS
Autonomous Vehicles
Honors Thesis
Thesis

In this thesis, I will explore the current ethical debate surrounding autonomous vehicles. I explore the following research questions: 1. What legislation already exists regulating the design and use of autonomous vehicles, and how, if at all, does ethics play a part in these laws? 2. Is ethics perceived as an important factor or consideration for AVs? 3. What common themes or patterns of discourse emerge in discussion of AVs and related ethical challenges? 4. What specific concepts are seen as the most important or relevant when discussing AVs? 5. With regard to AVs facing ethically challenging scenarios, what differences in attitude can be observed among different groups of people? Utilitarianism is the most common system of ethical thought referenced when discussing the ethics of AVs, probably due to its relative simplicity and familiarity. Indeed, utilitarianism proved to be a strong enough value to override even an otherwise consistent moral philosophy, although when utilitarian ideals are not at stake people tend to default back to thinking in terms of who is in the wrong, rather than how many people are affected. However, people were considerably less in favor of a utilitarian AV when faced with the idea of riding in one themselves. This discrepancy will need to be addressed and overcome if utilitarian AVs are to become mainstream.
The Role of Liquidity and Substitution Effects of Unemployment Insurance in the Great Recession
Keywords:  Department of Economics
Unemployment insurance
moral hazard
liquidity effect
expectations
Stanford Department of Economics
Thesis

In response to the 2007 recession in the United States, the federal and state governments extended the duration of unemployment insurance benefits for millions of people by 13 to 72 weeks. Using data from the 2008 panel of the Survey on Income and Program Participation, this paper proceeds in three steps. I first estimate the effect of these extensions on the likelihood of re-employment for the pooled sample. I compare these estimates to others made using data from the Current Population Survey. I then investigate whether the effect is heterogeneous across individuals with different levels of liquid wealth. I find evidence that the effect is heterogeneous, which implies the presence of a substantial liquidity effect. Finally, I investigate the hypothesis that liquidity effects translate into improved post-unemployment wages. I find no evidence for this hypothesis.
The role of morphology in the ecology of New World direct-developing Anurans
Keywords:  Department of Biology
Ecomorphology
Terrarana
Anura
Morphology
Ecology
Human Disturbance
Thesis

Ecomorphology links morphological adaptation to ecological function. The direct-developing Neotropical frog clade Terrarana includes multiple speciose genera occupying a numerous ecologies with specific microhabitat affiliations (Pedial et al. 2014, AmphibiaWeb 2016). They inhabit Central and South America, where they have been able to cover a wide geographic and elevational range in part due to their unique development and life history. However much of their preferred moist subtropical and tropical forests have been subject to deforestation and land use change (Redo et al. 2012), leading to the extinction and endangerment of many species ill-equipped to survive in segmented forests and open pastures (IUCN 2008). I investigated the relationship between morphology and ecology of species within three genera of the clade Terrarana: Craugastor, Eleutherodactylus, and Pristimantis to understand how and why certain species struggle to survive in disturbed habitats while close relatives thrive. I aimed to answer the questions: What morphological features best sort between ecologies? Are species of certain ecologies more successful in invading disturbed habitats? What differences in morphology do disturbance-tolerant frogs possess? I characterized species by microhabitat and generalized environment, and found that species hind limb length best sorted genera and environments, but their forelimb length best sorted between microhabitats. Arboreal frogs were most common in disturbed landscapes, along with species of the genus Eleutherodacytlus. Using computational approaches, I found evidence of a similar pattern of filtering for smaller body size in disturbed habitats across genera and microhabitats. These results suggest that exaptations have predisposed some species as disturbance-tolerant, while other species may have been filtered out of some habitats in part due to morphology.
The Sky is Falling: An Evaluation of Policy Responses to the Orbital Debris Problem
Keywords: Orbital Debris
Space Debris
Kingdon's Three Streams
Commercial Space
Space Law
Space Policy
Text
Thesis

In the last 60 years, humankind has littered the space around our planet with
debris. The accumulation of that debris presents dangers to both current and future
activities in space. In response to this problem, policymakers at the national and
international levels have enforced policies to mitigate the creation of new debris.
This paper examines the relationship between the growth of the orbital debris
problem and those policies, evaluating potential political science explanations to
explain the relationship. The results show that Kingdon’s “three streams” theory,
where the convergence of a problem, a policy solution, and a political opportunity
propels an issue onto the political agenda, best accounts for the positive
relationship observed between orbital debris and policy responses. Finally, this
paper evaluates how the entry of new private, players into the launch game will
worsen the orbital debris problem long-term. It examines the relationship between
the debris problem and policy into the future, concluding that the continuance of
current mitigation efforts is a more likely policy future than a shift to the type of
active removal policies necessary to solve the orbital debris problem.
The Souls of White Teachers: Racial Consciousness Development of In-Service Teachers
Keywords: Whiteness
critical Whiteness studies
White teachers
race
critical race theory
racial consciousness development
in-service teachers
Thesis

In 2014, 82% of public school teachers in the United States were classified as White, whereas more than 50% of public school students were students of color. Research has extensively documented the misguided and harmful attitudes about race that many White teachers bring to the classroom, ranging from cultural deficit thinking, to believing in the myth of colorblindness, to denying the history and current situation of racism in the United States. However, research has also revealed that attempts to engage White teachers in conversations around race spark defensive, guilty, and hostile reactions. Therefore, more research is needed to understand how racial consciousness development can occur for White in-service teachers. My thesis investigated White racial consciousness development through the lens of ten White public school teachers in Portland, Oregon, who lead racial equity professional development workshops in their respective schools. My study asked the question: What factors contributed to the racial consciousness development of White in-service teachers? Data were collected in semi-structured interviews, and analysis revealed the following factors as influential in my participants’ racial consciousness development: relationships with people of color, mentoring relationships, and teaching relationships with students of color; learning settings; experiences as a racial minority; intellectual curiosity; and experiences of marginalization. Together, these factors enhanced three components of the White teachers’ racial consciousness: knowledge, practice, and commitment. My findings suggest that school districts and schools of education must find opportunities to not only increase White teachers’ knowledge and practices around racial equity, but also opportunities to deepen their commitment and motivation to engage in anti-racist work.
Theoretical analysis of heterogeneous catalysis for energy storage and conversion - The interconversion between formic acid and carbon dioxide and methane oxidation on transition metals [electronic resource]
Keywords: Chemical Engineering.

Recent advances in computing power mean that it is now possible to tackle complex scientific challenges using computational methods. In this thesis, we employ density functional theory (DFT) and microkinetic modeling to take a meaningful step toward achieving the ultimate goal in the field of catalysis research, the rational design of catalyst materials. The interconversion between formic acid and carbon dioxide with relevance to the storage of hydrogen, and methane oxidation with relevance to the efficient utilization of natural gas are used as examples of heterogeneous catalysis to demonstrate our methodology to interpret catalytic trends and identify promising catalyst materials.