VictorJuiz/thesis huggingface dataset:
Leveraging Students' Intuitive Knowledge About the Formal Definition of a Limit

This dissertation explores the roles of students' intuitive knowledge in learning formal mathematics. The formal definition of a limit, or the epsilon-delta definition, is a critical topic in calculus for mathematics majors' development. It is typically the first occasion when students engage with rigorous, formal mathematics. Research has documented that the formal definition is a roadblock for most students in calculus, but has also de-emphasized the productive role of their prior knowledge and sense making processes. The temporal order of delta and epsilon has been suggested as a conceptual obstacle for students in understanding the structure of the formal definition. The dissertation investigates the nature of and the degree to which the temporal order of delta and epsilon is a difficulty for students. The fine-grained analysis of semi-structured interviews with elementary calculus students reveals a large repertoire of reasoning patterns about the temporal order. A microgenetic study of one student shows the diversity of knowledge resources and the complex process of reasoning. Knowledge in Pieces (diSessa, 1993) and Microgenetic Learning Analysis (Parnafes & diSessa, 2013, Schoenfeld, Smith & Arcavi, 1993) provide frameworks to explore the details of the structure of students' prior knowledge and their role in learning the topic. The study offers and examines the impact of an instructional treatment called the Pancake Story, designed specifically to productively link to students' intuitive knowledge. Leveraging the notion of quality control, the instructional treatment offers an alternative to the idea of functional dependence in reasoning about the temporal order of delta and epsilon. A detailed case study shows the process by which a student incorporates resources from the story into her existing knowledge about the temporal order. The findings in this dissertation support the claim that understanding the process of learning requires serious accounting for student's prior knowledge.

Advisor: Schoenfeld, Alan H.
Representing the Gaichi in Japanese Detective Fiction

This dissertation examines the relationship between Japanese detective fiction and the territories under Japanese colonial rule, areas such as the South Seas, Korea, and Manchuria known collectively as the "outer territories" (gaichi), during the early 1930s. It analyzes the works of three detective fiction writers: Yumeno Kyusaku (1898-1936), Oguri Mushitaro (1901-1946), and Kim Nae-Seong (1909-1957). The colonial settings of their works have various functions. In Kyusaku's work, these are largely domesticated through the use of tropes and recognizable images. Through these tropes and images, he depicts colonial space as a site where community is lost, but can be recuperated through the violence of suicide. On the other hand, Oguri's work depicts colonial space as completely unfamiliar, not only through the descriptions of a contaminating, foul landscape, but also by utilizing the conventions of a locked room mystery. In doing so, Oguri challenges the scientific conceit of this subgenre of detective fiction, a conceit also present in the story's inclusion of eugenics discourses. Kim Nae-Seong's detective fiction differs from those of Oguri and Kyusaku by eliding the otherness of the colonial landscape. That is, his works portray Seoul and Pyongyang as extensions of the metropole, generic urban sites of mystery. Taken together, this set of texts illuminates the intersection of a popular genre with colonial discourses during the fraught period of the 1930s.

Advisor: O'Neill, Daniel C.
Data-Driven Approaches for Sensing and Control of Robot Manipulators

In a sensing rich system, a large amount of data can be obtained over time and utilized to improve the performance and functionality of a robotic system. Data-driven approaches emphasize on the utilization of auxiliary sensors, sensor fusion, and data learning. Real-time control systems of robotic systems often run at kilo-Hertz sampling frequencies. New data is obtained from a variety of feedback sources every one or a few milliseconds. Auxiliary sensors provide additional feedbacks and enable sensor fusion. This dissertation presents a series of data-driven approaches to improve the sensing and control of robot manipulators from several aspects, including sensor fusion for motion sensing, statistical learning for feedback compensation, nonparametric learning control, and intelligent modeling and identification./nIn regard to the limited sensing capability of conventional indirect drive-trains of industrial robots, a sensor fusion approach based on auxiliary optical and inertial sensors is introduced for direct motion sensing of robot end-effectors. The approach is especially useful to applications where high accuracy is required for end-effector performance in real-time. Meanwhile, for the scenarios where auxiliary sensor are not allowed, a statistical learning algorithms is developed for sensing compensation so that control of systems with limited feedback capability can be significantly improved. A major application of the approach is vision guidance of industrial robots. The proposed learning approach can significantly increase the visual tracking bandwidth without requiring high-speed cameras./nBesides improving the sensing capability of robots, nonparametric learning control is developed to control systems with complex dynamics. A major motivation of the approach is robotic laser and plasma cutting. Furthermore, to obtain high-fidelity models more efficiently, planning and learning algorithms are discussed for intelligent system modeling and identification. The applications of the proposed approaches range from vision guided robotic material handling to precision robotic machining. Various tests are designed to validate the proposed approaches.

Advisor: Tomizuka, Masayoshi
Socialist Transformation in the Democratic Republic of Vietnam

In this dissertation, I examine the controversial land reform campaign carried out by the Vietnamese Workers' Party (VWP) in the Democratic Republic of Vietnam (DRV) from 1953 to 1956. The VWP leadership based the campaign on Maoist models and, indeed, planned and executed it with the help of Chinese Communist Party (CCP) advisers. As with land reform in China, the VWP's version involved sending thousands of hastily trained cadres into rural communities to teach villagers about class struggle, to organize public trials of alleged class enemies (followed in many cases by public executions), and to oversee the redistribution of land and personal belongings confiscated from those targeted by the campaign./nA few weeks after the completion of the land reform in the summer of 1956, the VWP leaders apologized publicly to the North Vietnamese people, stating that "errors" had been committed during the campaign's implementation. The public apology included a promise that these "errors," where possible, would be "corrected" in a new campaign. The key idea of this official explanation was that the negative phenomena of the campaign (primarily its extraordinary violence) had been an unfortunate accident, and not what the Party leaders had intended to happen when they formulated the land reform policy. Something had gone awry during the campaign's implementation, with cadres committing "leftist deviations," which were not "discovered" by the Party leaders until it was too late./nUsing a range of different sources that have become available to scholars in the last two decades, I test the validity of this official VWP explanation for what had happened during the land reform. I also test the validity of the VWP leadership's original justification for carrying out the campaign, which was the notion that peasant misery in the countryside in early 1953 stemmed primarily from "feudal exploitation." I argue that both narratives do not stand up to close scrutiny and that the land reform unfolded largely as planned by the Party leaders.

Advisor: Zinoman, Peter
Spiders in California's Grassland Mosaic: The effects of native and non-native grasses on spiders, their prey, and their interactions

Found in nearly all terrestrial ecosystems, small in size and able to occupy a variety of hunting niches, spiders' consumptive effects on other arthropods can have important impacts for ecosystems. This dissertation describes research into spider populations and their interactions with potential arthropod prey in California's native and non-native grasslands. In meadows found in northern California, native and non-native grassland patches support different functional groups of arthropod predators, sap-feeders, pollinators, and scavengers and arthropod diversity is linked to native plant diversity./nWandering spiders' ability to forage within the meadow's interior is linked to the distance from the shaded woodland boundary. Native grasses offer a cooler conduit into the meadow interior than non-native annual grasses during midsummer heat. Juvenile spiders in particular, are more abundant in the more structurally complex native dominated areas of the grassland. Potential prey species and abundance differ along the trajectory from woodland boundary to meadow interior and may have consequences for the survival of juvenile spiders that reside primarily near the woodland boundary./nSpiders' ability to influence the eating habits of potential prey species is regulated by temperature and grassland characteristics. In experimental wolf spider enclosures, cooler habitats in which spiders were present evidenced lower herbivory by large chewing invertebrates. Herbivory differed across a gradient of temperature and sunlight but newly restored plants in exposed and warmer soil faced higher rates of herbivory than established plants; herbivory may be better mediated by spider activity in cooler environments.

Advisor: Power, Mary E
McBride, Joe R
Ultrafast Molecular Dynamics Studied Via Extreme-Ultraviolet Transient Absorption Spectroscopy

Recent developments of isolated, sub-femtosecond light pulses generated via upconversion of commercially available 800 nm light sources have allowed for the study of chemical dynamics in the tens to few hundred attosecond (1 attosecond = 1 as = 1 x 10-18 s) temporal domain. Electron dynamics, or motions of electrons, occur on this timescale. These dynamics govern fundamental quantum mechanical processes that have applications ranging from chemical reactions to charge transfer and beyond./nIn this dissertation, an attosecond transient absorption apparatus was constructed to measure electron dynamics in atoms and molecules. Chapter 2 discusses the considerations made in building the apparatus, a description of the individual components and processes that comprise the instrument, and the current performance of the experimental system. In short, the instrument is capable of resolving dynamics as short as ~200 as in duration with photons spanning the spectral ranges of either 50-73 eV or 65-90 eV. Chapter 3 addresses the characterization techniques utilized to ensure optimal performance of the attosecond transient absorption apparatus; methods to measure laser pulse temporal durations, spatial beam profiles, extreme-ultraviolet (XUV) light pulses, and photoelectron kinetic energies are documented./nAfter construction of the attosecond transient absorption apparatus, preliminary experiments were conducted to lay the groundwork for studies of electron dynamics in molecular systems. Chapter 4 documents a method by which integrated XUV absorption cross section ratios of atoms and molecules may be determined; this information is necessary for quantifying branching ratios of chemical reactions using XUV transient absorption spectroscopy. In the conclusion, chapter 5 characterizes two molecular systems, CH3Br and Br2, which may be ionized by strong fields potentially to produce a superposition of two electronic states, thus forming an electronic wavepacket that may be studied via attosecond transient absorption spectroscopy. Such systems provide a framework for understanding simple electronic wavepackets in molecules before progressing to studying these dynamics in more complicated systems.

Advisor: Leone, Stephen R
La ciudad de una y mil caras. Nociones de Tijuana y la identidad tijuanense

This study examines the representation of the city of Tijuana in the literature of four local writers: Federico Campbell, Luis Humberto Crosthwaite, Rosina Conde, and Heriberto Yépez. My discussion centers on how their writings confront and interrogate formulas that, coming from centers of cultural power in both Mexico and the United States, are used to explain this city's sociocultural logic: Tijuana as a capital of sin, as a pass-through city, as a threat to the so-called "national identity," or as the quintessential illustration of a process of cultural hybridity that transcends former ideas of class, nation, and identity. I argue that these writers have reclaimed a vision of Tijuana as an internal point of reference for themselves as artists and also as individuals. Instead of countering stereotypes with similarly totalizing metaphors, they reveal a set of diverse realities through the complex narratives of the individuals who interact in this space. Within this framework, they not only expose the way in which the hegemonic descriptive modalities of Tijuana are articulated and inscribed in the collective imagination, but also invite us to consider the city's inner sociocultural and economic borders, and the conflicting coexistence to which they give rise. In doing so, I also argue, their writings prevent us from oversimplifying border identities and border literature.

Advisor: Tarica, Estelle
Understanding the Gap Between Fertility Intentions and Outcomes

The ability of women to safely and effectively control their fertility is a critical health and human rights issue. Family planning provides a range of health, social, and economic benefits for women and their families, yet more than 200 million women worldwide who wish to delay or limit their childbearing are not using any method of contraception. The global health community has recently seen renewed interest in promoting family planning use worldwide. This increased focus on family planning raises questions about how best to deliver reproductive health services to the women who need them, which requires a clearer understanding of how women make decisions about their fertility and how such decisions are carried out./nThis dissertation explores the reasons why women's stated fertility intentions do not always align with their fertility behaviors or outcomes. The first paper explores the concept of unmet need for family planning by using both quantitative and qualitative methods to better understand why women who want to prevent a pregnancy choose not to use contraception in Luanda Province, Angola. The second paper considers the social context in which women make decisions about their pregnancies in a post-abortion care context in Zanzibar, Tanzania. The third paper examines how women's experiences in early childhood shape their risk of unintended pregnancy later in life in the United States./nThese dissertation papers provide three distinct examples of how researchers' and policy makers' perceptions of women's reproductive decision-making may fail to recognize or address crucial determinants of fertility intentions, behaviors, and outcomes. In particular, they highlight the importance of considering women's fertility decisions within the context of their full reproductive lives, and point to the need for further research to better understand how such decisions shift over the course of women's lives. Policies and programs that can accommodate how these decisions are formed and changed over time are necessary for ensuring that all women have the right to make decisions about their reproduction and to enact these decisions in safe and effective ways.

Advisor: Abrams, Barbara
Single-Molecule Studies of Intraflagellar Transport in Chlamydomonas

Intraflagellar transport (IFT) is a universal process that is required for the assembly and maintenance of all eukaryotic cilia and flagella. Defects in IFT are linked to a wide range of human diseases, including polycystic kidney disease and retinal degeneration. IFT has been implicated in sensory and motile ciliary functions, but the mechanisms of this relationship remain unclear./nWe used Chlamydomonas flagellar surface motility (FSM) as a model to test whether IFT provides force for gliding of cells across solid surfaces, and whether IFT transports flagellar membrane glycoproteins (FMGs). We show that IFT trains are coupled to FMGs in a Ca2+-dependent manner. IFT trains transiently pause through surface adhesion of their FMG cargos, and dynein-1b motors pull the cell towards the distal tip of the axoneme. Using the IFT-FMG linkage, we performed optical trapping studies to measure the force produced by single IFT trains. The stall force measurements show that each IFT train is transported by at least four active motors. Opposite-polarity motors are reciprocally coordinated to avoid a tug-of-war. Our results demonstrate the mechanism of Chlamydomonas gliding motility and suggest that IFT plays a major role in adhesion-induced ciliary signaling pathways./nTo understand the regulation mechanism of IFT, key information needs to be acquired by monitoring IFT remodeling at the turnaround zones. However, the collective behavior of IFT particles poses unique challenges, because individual IFT trains often cannot be resolved at the flagellar tips and bases. We developed a photobleaching gate assay to track single molecules in dense specimens. The assay controls the number of fluorescent particles in a region of interest by photobleaching its boundary. To test this method, we tracked GFP-labeled receptors at a 100 ms temporal resolution on a live cell membrane, even though the average distance between the receptors is less than 50 nm. We directly observed ligand-induced dimerization of epidermal growth factor receptor (EGFR) on a cell membrane./nWe applied the photobleaching gate method to IFT in Chlamydomonas. We tracked individual IFT complexes along the length of a cilium and observed their remodeling at the ciliary tip. After transported by kinesin-2 to the flagellar tip, IFT trains split and recombine, and are transported back to the flagellar base bydynein-1b. Kinesin associated protein (KAP), on the other hand, diffuses back to the base after reaching the tip. On the basis of the results above, we propose new models for mixing and remodeling of IFT particles at the flagellar tip, coordination of IFT motors and flagellar length control.

Advisor: Yildiz, Ahmet
Theory and Application of Path Probability Functionals in Population Genetics

Calculations based on the Wright-Fisher process and its limits are the primary tools of population genetics theory. Decades of theoretical work have elucidated much about the properties of the neutral Wright-Fisher model, in which different mutations have the exact same Darwinian fitness. The model becomes significantly more complicated when the action of natural selection is taken into account, and we are only just beginning to understand the details of evolution subject to natural selection. In this thesis, I take a path integral approach to understanding the Wright-Fisher diffusion with selection, in contrast to the typical approach, using partial differential equations. This allows me to use powerful machinery from quantum physics and mathematical finance to come up with novel ways to perform difficult calculations. The work here is composed of three parts. First, I develop a rejection sampling approach to obtaining Wright-Fisher diffusion paths when the allele frequency trajectory is conditioned to start and end at certain points (such paths are called bridges). Next, I use perturbation theory to calculate the transition densities of the Wright-Fisher process with genic selection, assuming weak selection. Finally, I implemented a Markov chain Monte Carlo approach to estimating selection coefficients from allele frequency time series that makes use of aspects of both of the previous chapters.

Advisor: Slatkin, Montgomery
Berlusconi Between Politics and Popular Culture

In this dissertation I contextualize the political protagonism of Silvio Berlusconi with respect to important heroes of contemporary Italian popular culture. Comparing Berlusconi to the protagonists of Italy's dramatized television series and TV-movies, I consider the political and pop cultural significance of his behavior through Antonio Gramsci's theories of hegemony and the national popular. I locate Berlusconi's political connection to contemporary Italian popular culture by briefly contrasting it to past iterations of the politics-popular culture relationship in Italy and the United States, and to its likely future configurations in Italy./nMy research shows that while Berlusconi is often a potent and educative symbol of a hegemonic, conservative national popular culture, he is also often at odds with important components of said culture. This finding adds nuance to most contemporary considerations of Berlusconi's power, which frequently posit his political and cultural influence as monolithic. Increasing social and cultural fragmentation in Italy suggests that the "Berlusconis" of the future will likewise embody a charismatic and spectacular form of politics, though they will be bereft of Berlusconi's wider political-cultural syncing, which, while never perfect, has nevertheless been the historically most significant facet of his influence.

Advisor: Fuller, Mia
Quasiparticle Coherence, Collective Modes, and Competing Order in Cuprate Superconductors

In recent years, the study of cuprate superconductors has been dominated by the investigation of normal state properties. Of particular interest is the nature of interactions between superconductivity and other incipient orders which emerge above the superconducting transition temperature, Tc. The discovery of charge density wave (CDW) correlations in YBa2Cu3O6+x (YBCO) and HgBa2CuO4+d (Hg-1201) has established that some form of charge order is ubiquitous in the cuprates. In this work, we explore the non-equilibrium dynamics of systems which sit near the boundary between superconductivity and competing orders./nUltrafast pump-probe spectroscopy is ideally suited to the study of competing order. Exciting the sample with an optical pulse perturbs the system from equilibrium, altering the balance between the co-existing orders. The return to equilibrium is then monitored by a time-delayed probe pulse, revealing multiple decay processes as well as collective excitations. We first apply this technique to Hg-1201, conducting a detailed study of the phase diagram. At temperatures near Tc, the pump pulse induces a non-equilibrium quasiparticle population. At Tc we observe a doping-dependent peak in the relaxation time of these quasiparticles which we associate with a divergence in the coherence time of the fluctuating CDW. Using heterodyne probing in the transient grating geometry, we are able to disentangle the transient reflectivity components associated with superconductivity and the pseudogap, domonstrating competition across the phase diagram. We also discuss the observation of a sharp transition in the nature of the pseudogap signal at ∼ 11% doping./nIn YBCO, we explore the temperature and doping dependence of coherent oscillations excited by the pump pulse. We associate these oscillations with the excitation of the CDW amplitude mode, and model their temperature dependence within the framework of a Landau model of competing orders./nWe conclude with an investigation of pseudogap dynamics in the electron doped compound Nd2-xCexCuO4+d as a function of temperature and doping. Near optimal doping, we observe the impulsive excitation of a critically damped mode, with time-temperature scaling consistent with quantum-critical fluctuations. This mode competes with superconductivity in a dynamical fashion, such that the suppression of this mode below Tc can be lifted via photo-evaporation of the superconducting condensate.

Advisor: Orenstein, Joseph W