VictorJuiz/thesis huggingface dataset:
Narratives of collective belonging [electronic resource] : American Jews and the history of Israel
Keywords: Education.

Article I explores the way a diverse sample of American Jewish parochial school students narrated the history of Israel. It analyzes 438 responses to the prompt: "In 2-3 paragraphs, tell the history of the State of Israel as you understand it." The students' responses suggested that many students are aware of the tensions between various historical accounts and adopt different strategies to negotiate between critical historical analysis and Jewish collective belonging. Although there were no differences in the content of the accounts by students' religious denomination or prior study of Israel's history, students adopted different approaches to negotiating critical analysis and collective belonging. Some students told stories of Jewish heritage without taking into account other possible perspectives. Some students engaged with challenges to their inherited stories but only to dispute them. Finally, some students managed to synthesize multiple narratives together while still using a Jewish perspective to frame their account. This last strategy suggests that students can be historically sophisticated without abandoning a commitment to their heritage. Article II examines changes to Jewish parochial students' narratives of the history of Israel after a two and a half week trip there. Seventeen students were interviewed about the history of Israel before and after a two and a half week class trip. Before the trip, most students' accounts lacked logical connections among the different events. Instead, students listed events in chronological order like a timeline. The observations on the trip revealed that the tour guide told a story of Jewish exile and return. After the trip, most students adopted the tour guide's narrative structure of Jewish exile and return. This finding suggests that short trips to Israel may be able to teach a coherent narrative, something formal history classrooms struggle to do. At the same time, it raises questions about the appropriate role of narrative frameworks in history education: to what extent is it possible to teach a narrative framework and still leave room for student inquiry? Article III traces the emergence of anti-Zionism in the American New Left before 1967. Most existing research sees contemporary anti-Zionism as a reaction to Israel's occupation of the West Bank and Gaza after the 1967 War. This article finds the roots of anti-Zionism in the racially charged rhetoric of Malcolm X and the Nation of Islam in the early 1960s. It argues that particular individuals influenced by Malcolm X and even working in his Organization for Afro-American Unity carried his ideas into the Student Non-Violent Coordinating Committee, which published a harshly anti-Zionist newsletter in the summer of 1967 just after the end of the war in the Middle East. From SNCC, this racial interpretation of Zionism spread into the New Left.
Navigate, read, construct [electronic resource] : supporting immigrant children to comprehend English texts
Keywords: Education.

This study examined what strategies immigrant children use when trying to comprehend English texts, and how such children could be taught more effective strategies. Six children between the ages of 8; 7 and 11; 1 participated in the study; all were native speakers of Spanish who had moved to the United States no earlier than one year prior to the start of the study, and all attended the same elementary school in northern California. I used educational design research to plan, implement, and evaluate a plan for instruction for these students, and conducted periodic clinical interviews to learn about the children's approaches to comprehending English texts. Analytical induction was used to uncover patterns in the interview data, and these patterns were linked to instructional antecedents through review of teaching logs and notes on videos of the lessons. I found that all students, regardless of the amount of experience they had with English, had multiple strategies for drawing meaning from English texts. When hunting for answers in an article, they followed a universal pattern of navigating to a promising section of the text, reading it through words or pictures, and constructing a complete answer that went beyond parroting the text. Students' strategies for accomplishing these tasks changed over time, and many of their changes can be directly linked to lessons taught in class. Some strategies worked better for students with more exposure to English and proved to be inappropriate for children with less English experience. These findings have implications for the design of programs to support the burgeoning population of newcomer students in the United States.
Netroots organizing, from viral marketing to Barack Obama [electronic resource] : how Berger and Luckmann's theory of institutionalization resolves the paradox of embedded agency
Keywords: Management Science and Engineering.

The present dissertation is a historical ethnographic case study of the emergence of the institution of netroots organizing in Democratic Party politics. It offers five contributions to the sociological study of institutions: First, the dissertation elucidates how Berger and Luckmann's (1967) theory of institutionalization and its constituent moments of internalization, externalization, and objectivation resolve the paradox of embedded agency that occurs when instititutional researchers focus on either the constraining or the empowering sides of institutions. Second, the dissertation shows how the theory explains institutional work—the reproduction, disruption, and change of existing institutions and the emergence of new ones—by means of problematization during the transition from internalization to externalization. Third, the dissertation illustrates that actions and meanings are involved in a continuous dialectical interplay such that researchers' understanding of institutional dynamics is incomplete without a prior understanding of habitual developments. Fourth, the dissertation reveals that institutional entrepreneurs are sometimes social constructions resulting from institutionalization, not the source of institutionalization. Rather, anarchic organizing—the application of existing habits and institutions to emerging probems—can serve as the impetus for novel institutionalization. Agents only construct interests once new habits and institutions prove valuable, and they then develop rationalized myths that ascribe the status of entrepreneurs to those perceived to have constructed these habits and institutions. Fifth, the dissertation demonstrates that Berger and Luckmann's (1967) theory shows the dynamics of delegitimation when the powerful and less powerful encounter each other and illustrates some of the options available to the less powerful when confronted with conflict.
Neural mechanisms of learning and memory in the human medial temporal lobe [electronic resource]
Keywords: Psychology.

The medial temporal lobe is critical for enabling memory for the events of one's personal past. However, whether medial temporal lobe subregions perform shared or qualitatively distinct computations to support these memories is a topic of debate. One prominent theoretical perspective proposes that complementary behavioral expressions of memory for past events are enabled via the creation of separated versus overlapping neural representations for events that share similar elements, and that these representations are formed by the hippocampus and medial temporal lobe cortex, respectively. A wealth of empirical data has examined this proposal by asking whether these complementary behavioral expressions of memory are differentially linked to integrity and / or functional activation of the hippocampus and medial temporal lobe cortex. Here, we examined complementary medial temporal lobe computations through a different lens, and asked whether the degree of neural overlap in the hippocampus and medial temporal lobe cortex elicited by stimuli during encoding is differentially linked to the ability to recognize those stimuli in the future. We addressed this question with two experiments using converging methodologies. In Experiment 1 we used high-resolution functional magnetic resonance imaging and pattern similarity analyses to quantify neural overlap across the spatial topography in medial temporal lobe subregions during encoding. We found that the relationship between pattern similarity during encoding and subsequent memory dissociated across the hippocampus and medial temporal lobe cortex: later memory was linked to greater across-item pattern distinctiveness in the hippocampus, but to greater across-item pattern similarity in medial temporal lobe cortex. Additionally, by comparing neural patterns elicited by individual stimuli regardless of later memory for these stimuli, we found that perirhinal cortex and parahippocampal cortex exhibited differential content sensitivity for multiple stimulus categories, whereas the hippocampus failed to demonstrate such content sensitivity. In Experiment 2 we used intracranial electroencephalography to quantify neural overlap across the temporal evolution of population-level neural activity in medial temporal lobe subregions during encoding. We found that later memory was linked to greater across-item pattern distinctiveness in the hippocampus but not in medial temporal lobe cortex, and that the strength of these relationships was modulated by the demands on behavioral expressions of memory during retrieval. These data provide novel evidence for complementary learning mechanisms across the hippocampus and medial temporal lobe cortex, and suggest that these mechanisms operate across both spatial and temporal dimensions of neural codes.
Neuronal Activity-Mediated OPC Proliferation Following White Matter Injury
Keywords:  Department of Biology
Biology
Neurobiology
Remyelination
Optogenetics
Lysolecithin
Multiple Sclerosis
Thesis

Multiple Sclerosis is a neurological disorder characterized by demyelinated lesions in the central nervous system (CNS), inflammation mediated largely by autoimmune T cells, and eventual motor and sensory loss. Remyelination in the disease is often slow or incomplete, and mechanisms of remyelination are still largely undescribed. Normal myelination occurs through the differentiation of oligodendrocyte precursor cells (OPCs) into functionally mature oligodendrocytes capable of wrapping myelin onto axons. Electrical activation in a premotor neural circuit via optogenetic stimulation induces proliferation of OPCs, oligodendrogenesis, and increased myelination of that circuit. This mechanism could potentially be used as a tool to enhance remyelination after injury. In this work, we determine whether optogenetic stimulation can enhance remyelination in the motor cortex. We show that optogenetic stimulation increases proliferation of OPCs in the corpus callosum following lysolecithin-induced demyelination of that region. Since OPCs are the precursors to mature oligodendrocyts and myelin formation, optogenetic stimulation may provide the first trigger to remyelination.
New Affordable Housing and School Quality Measures in Florida
Keywords:  Department of Economics
Stanford Department of Economics
affordable housing
school quality
Florida
event-study model
standardized test scores
Free and Reduced Lunch Program
Thesis

This paper examines the impact of introducing new affordable housing on the school quality, as defined by standardized test scores, of nearby schools. The results serve to allay the concerns of opponents of affordable housing who may fear the quality of their schools would deteriorate, as well as inform policy makers considering where to place new affordable housing. I utilize data on affordable housing and schools from the state of Florida. I use an event-study model to compare the standardized test scores of schools before and after the introduction of affordable housing nearby. Nearby “untreated” neighbors who do not receive new affordable housing serve as the matched control. I find no statistically significant general impact from the introduction of affordable housing, with a slightly negative general impact on test scores as the size of the new affordable housing increases. However, I find that the effect is dependent on socioeconomic status as measured by Free and Reduced Lunch Program eligibility. I show that standardized test scores increase in middle schools with low rates of Free and Reduced Price Lunch eligibility after the introduction of new affordable housing. While further study is needed, policymakers should take note that introducing new affordable housing near schools of a higher socioeconomic status causes the average achievement of the entire school to increase.
New constructions and computations in rigid and flexible symplectic geometry and applications to several complex variables [electronic resource]
Keywords: Mathematics.

This thesis is divided into three parts. In the first part, we give a complete characterization of those disk bundles over surfaces which embed as rationally convex strictly pseudoconvex domains in $\C^2$. We recall some classical obstructions and prove some deeper ones related to symplectic and contact topology. We explain the close connection to Lagrangian surfaces with isolated singularities and develop techniques for constructing such surfaces. Our proof also gives a complete characterization of Lagrangian surfaces with open Whitney umbrellas, answering a question first posed by Givental in 1986. In the second part, we introduce a class of Weinstein manifolds which are sublevel sets of flexible Weinstein manifolds but are not themselves flexible. These manifolds, called subflexible, exhibit rather subtle behavior with respect to both pseudoholomorphic curve invariants and symplectic flexibility. We construct a large class of examples and prove that every flexible Weinstein manifold can be Weinstein homotoped to have a nonflexible sublevel set. This resolves some recent open questions in symplectic flexibility. In the third part, we establish an infinitesimal version of fragility for squared Dehn twists around even dimensional Lagrangian spheres. The precise formulation involves twisting the Fukaya category by a closed two-form or bulk deforming it by a half-dimensional cycle. As our main application, we compute the twisted and bulk deformed symplectic cohomology of the subflexible Weinstein manifolds constructed in the second part.
New experimental tests for gravity and dark matter [electronic resource]
Keywords: Physics.

The behavior of gravity is well understood and highly constrained on length scales from millimeters to the size of the Solar System. New physics, such as extra dimensions or new forces, may modify the behavior of gravity below a millimeter. On the other end of the spectrum, observations of galaxies, galaxy clusters, supernovae, and the Cosmic Microwave Background all point to the gravitational dominance of dark matter and dark energy over the ordinary matter content of the Universe. It is therefore worth investigating, with high precision, the behavior of gravity at the longest distance scales as well. In this dissertation, I describe a recent proposal for a space-based experiment, optimized to test the inverse square law with great accuracy at scales of up to 100 AU. This is the largest length scale that can be reached with a direct probe using current technology. I also describe a new experimental strategy for testing putative signals of dark matter decay or annihilation. Merging galaxy clusters such as the Bullet Cluster provide a powerful testing ground for indirect detection of dark matter. The spatial distribution of the dark matter is both directly measurable through gravitational lensing and substantially different from the distribution of potential astrophysical backgrounds. I propose to use this spatial information to identify the origin of indirect detection signals, and show that even statistical excesses of a few sigma can be robustly tested for consistency--or inconsistency--with a dark matter source.
New insights into galaxy cluster astrophysics using the Suzaku X-ray satellite [electronic resource]
Keywords: Physics.

Galaxy clusters enable a broad range of astrophysical studies, from the microphysics of hot tenuous plasmas, to the physics of galaxy evolution, to constraining cosmological models. In particular, much can, and has, been learned from detailed studies of the nearest brightest systems, in which the relevant astrophysics can be viewed "in closeup". The focus of this thesis is the analysis of , and extraction of novel results from, observations of nearby galaxy clusters made with the Suzaku X-ray satellite. In particular, the first part of the thesis is focused on the analysis of data from Suzaku Key Project observations of the Perseus Cluster, the X-ray brightest cluster in the sky, which offered the most complete view to date of any galaxy cluster from its core to the outer edge. The results are presented across several chapters. In Chapter 2, we examine the behaviour of various physical properties of the intracluster medium (ICM), some of which, most prominently including the entropy, indicate a presence of density inhomogeneities at large radii (r> r500). In Chapter 3, we report evidence for large megaparsec-scale sloshing motions of the ICM in Perseus, a phenomenon which had not been observed before at these scales. In Chapter 4, we present the first spatially resolved study of the chemical composition of the ICM throughout the full volume of a cluster. Notably, we find a homogeneous distribution of heavy elements at large radii which indicates that these elements, produced by supernovae, were likely injected into and mixed with the intergalactic gas before galaxy clusters formed. In the second part of this thesis, I present a detailed spectral examination of Suzaku observations of the four X-ray brightest clusters, in order to search for the presence of a ~3.5 keV X-ray emission line. The presence of such a line has been claimed in some previous X-ray studies of the Perseus Cluster, and some other galaxies and clusters. It has been proposed that such a feature could be a decay signature from sterile neutrino dark matter. My results present a severe challenge to this interpretation. Alternative scenarios for the origin of the ~3.5 keV feature are discussed.
The new institutionalism of occupations [electronic resource]
Keywords: Sociology.

During the past few decades, licensure, a state-enforced mechanism for regulating occupational entry, quickly became the most prevalent form of occupational closure. Broad consensus among researchers is that licensure creates wage premiums by establishing economic monopolies. However, licensing has a much broader impact on occupational structure. Using a new occupational dataset, covering thirty years, I argue that, by redrawing boundary lines, licensing recreates occupational institutions and can have an effect on the wages, composition, and culture of an occupation. The first paper reveals that licensing, instead of increasing wages, creates a set of institutional mechanisms that enhance entry into the occupation, particularly for historically-disadvantaged groups, while simultaneously stagnating quality. The second paper shows that licensing eases access into occupations for immigrants, a majority of whom are in the high-skilled primary labor market, while leaving behind the most vulnerable immigrant labor groups. Finally, the third paper demonstrates that, though women enter licensed occupations at a higher rate than unlicensed occupations, they are also disproportionately clustered at the bottom of the wage distribution, resulting in increased within-gender inequality. At its core, closure is the erection of boundaries between groups that struggle for the exclusion of others, in order to monopolize resources. In focusing on the second part of this equation, resource monopolization, past theorists neglected to look closely at the boundaries, even though these boundaries can restructure a group in socially meaningful ways. Taking these effects together, my simple conclusion is that closure is much more than a monopoly mechanism -- it is reformative.
New materials for biomedical imaging in the second near-infrared window [electronic resource]
Keywords: Materials Science and Engineering.

Traditional medical fluorescence imaging uses wavelengths spanning the visible (400-700 nm) and infrared (700-900 nm) regions of the electromagnetic spectrum. These wavelengths display poor optical penetration depths as well as high levels of photon scattering and background autofluorescence. As a result, traditional medical fluorescence imaging cannot effectively resolve features below the surface of the skin (~0.4 mm penetration depths). We have demonstrated that fluorescence imaging past 1000 nm in an optical window termed the second near-infrared window (NIR-II; 1000-1700 nm) reduces the adverse interactions between light and tissue described above, leading to 5-fold higher tumor-to-background ratios with 10-fold deeper tissue penetration depths. Fluorescence imaging in the second near-infrared widow (NIR-II; 1000-1700 nm) is a powerful technique that gives doctors and researchers a view into the human body or turbid biological tissues. However, the development of this imaging modality relies on new materials with advanced optical properties. This work aims to develop highly purified single-walled carbon nanotubes (SWCNTs) of a single diameter with unique optical signatures that lower requisite doses for NIR-II tumor detection and treatment. Although SWCNTs provide a promising approach for future clinical applications, the development of organic NIR-II dyes similar in structure and pharmacokinetics to FDA-approved medical fluorophores is a faster route to the clinic. This work additionally presents the first NIR-II organic dyes with high levels of excretion as well as a high quantum yield.