VictorJuiz/thesis huggingface dataset:
Dante and the Florentine Chronicles

My research examines Dante's engagement with the traditions regarding collective memory in medieval Florence. In particular, it investigates the ways in which Dante responds to public and private attempts at forging both individual and collective identity in Florence. Selecting key chronicles, inscriptions and visual sources alluded to in the Commedia, the implications of Dante's representation in terms of his ideological response are then extensively discussed./nAfter introducing the central passages from the Commedia relevant to my project and a review of selected secondary literature on Dante and history, the dissertation introduces the Medieval Latin Chronica de origine civitatis florentiae as Dante's most important source regarding his city's foundation. In so doing, the textual readings are informed by the formation and control of memory, history and identity in historical context. Building on Dante's reliance on the Chronica, the dissertation reveals the continuity of civic historiography up to Dante's time and argues that Dante's engagement with the medieval Florentine collective memory tradition can be better understood through a close look at the shifting account of Florence's foundation from the Chronica to Brunetto Latini's Tesoro to the Commedia. In such a way, there is a development of the multifaceted problem of engagement with the ideologically charged materials that built collective memory in medieval Florence./nThe agents responsible for producing publicly displayed visual representations to legitimize their own perspective are then discussed. Building on the complex relationships between the Chronica, the Tesoro and the Commedia, the dissertation discusses the integration of two well-known visual productions with this textually mediated tradition: the statue of Mars and the primo popolo inscription on the Palazzo del Podestà. Thus, Dante's critical response to the politically charged construction of collective memory is further analyzed through the lens of the chronicle tradition in the Cacciaguida episode. An internal tension emerges between the allusions to the ethical perversion of the self-justifying political purpose of the chronicles' role, and the direct reference to the chronicle tradition in Cacciaguida's episode which is constructed over the exaltation of Florentine's moral virtues before the city's commercial and political expansion. In so doing, Dante seems to disconnect the foundational myths fabricated by the early chroniclers from any justification of an expansionist project, proposing instead a conservative political and social vision shaped by the traumas of the experience, both of the factionalized city and of his own exile.

Advisor: Ascoli, Albert
Botterill, Steven
Novel Material Integration for Reliable and Energy-Efficient NEM Relay Technology

Energy-efficient switching devices have become ever more important with the emergence of ubiquitous computing. NEM relays are promising to complement CMOS transistors as circuit building blocks for future ultra-low-power information processing, and as such have recently attracted significant attention from the semiconductor industry and researchers. Relay technology potentially can overcome the energy efficiency limit for conventional CMOS technology due to several key characteristics, including zero OFF-state leakage, abrupt switching behavior, and potentially very low active energy consumption. However, two key issues must be addressed for relay technology to reach its full potential: surface oxide formation at the contacting surfaces leading to increased ON-state resistance after switching, and high switching voltages due to strain gradient present within the relay structure./nThis dissertation advances NEM relay technology by investigating solutions to both of these pressing issues. Ruthenium, whose native oxide is conductive, is proposed as the contacting material to improve relay ON-state resistance stability. Ruthenium-contact relays are fabricated after overcoming several process integration challenges, and show superior ON-state resistance stability in electrical measurements and extended device lifetime. The relay structural film is optimized via stress matching among all layers within the structure, to provide lower strain gradient (below 10E-3/µm) and hence lower switching voltage. These advancements in relay technology, along with the integration of a metallic interconnect layer, enable complex relay-based circuit demonstration. In addition to the experimental efforts, this dissertation theoretically analyzes the energy efficiency limit of a NEM switch, which is generally believed to be limited by the surface adhesion energy. New compact (<1 µm^2 footprint), low-voltage (<0.1 V) switch designs are proposed to overcome this limit. The results pave a pathway to scaled energy-efficient electronic device technology.

Advisor: King Liu, Tsu-Jae
Population Genetic Effects of Recent Admixture

Admixture has played an important role in shaping genetic diversity in many human populations. Quantifying these effects is important not only for answering historical questions, but also for detecting selection, mapping disease genes, and estimating recombination rates. Many existing methods for estimating admixture times use spatial information from the genomes of admixed individuals, such as the distribution of admixture tract lengths or the two-point covariance function of their local ancestries. I first discuss some theoretical results about the length distribution of admixture tracts. I use simulations to show that, for recent admixture events, no existing population genetic model approximates this length distribution well. I introduce a new model, based on dyadic intervals, which is accurate in this regime more mathematically tractable. I then show how the distribution of admixture proportions within a population, as estimated by programs such as STRUCTURE, gives information about the population's admixture history and relate the moments of this distribution to the theory of multi-locus linkage disequilibria. Finally, I show how measures of three-locus linkage disequilbria can be used to improve on the resolution of existing admixture history inference methods.

Advisor: Nielsen, Rasmus
Epidemiologic, clinical and laboratory features of pediatric dengue in Nicaragua

Dengue virus is a flavivirus of worldwide importance, with approximately 4 billion people across 128 countries at risk of dengue virus infection. Most cases present as classic dengue fever, a debilitating, but self-limited illness that manifests with high fever, retro-orbital pain, severe myalgia or arthralgia, and rash. However, in some cases, illness progresses to life-threatening dengue hemorrhagic fever or dengue shock syndrome. The identification of distinguishing clinical and laboratory features that occur during the early febrile phase of illness is important for developing a clinical prediction algorithm to differentiate dengue from other febrile illnesses, and severe dengue from mild dengue. In addition, the success of community-based programs for preventing dengue indicates that identifying environments that could benefit from intervention at a community level is critical in order to have the greatest impact and to target limited resources./nThis dissertation focuses on data from two ongoing studies in order to investigate the epidemiologic, clinical and laboratory features of pediatric dengue in Nicaragua. Chapter 1 reports on the clinical and laboratory features of dengue virus infection in Nicaraguan children. The aims of the study were to examine the frequency of clinical signs and symptoms by day of dengue illness and to analyze the association of signs and symptoms with dengue virus infection during the early febrile phase of illness and over the course of illness./nChapter 2 reports on the association of lower low-density lipoprotein cholesterol levels with severe dengue outcome. The aim of the study was to delineate the trajectories of cholesterol levels over time by dengue virus infection status in order to understand the effect of dengue virus infection on cholesterol metabolism. We also sought to delineate their trajectories by dengue severity and to assess the effect of cholesterol level at presentation on development of severe dengue./nChapter 3 reports on individual-, household- and neighborhood-level determinants of dengue virus seropositivity in a community-based cohort. The aim of the study was to identify risk factors for DENV infection among children living in urban neighborhoods in Managua, Nicaragua. We also sought to determine the seroprevalence of dengue virus infection and identify individual- and household-level risk factors for dengue virus infection in neighborhood groups categorized by similar socioeconomic, infrastructural and ecological characteristics./nTogether, these studies present important findings on the natural history of pediatric dengue in Nicaragua and provide the basis for future research to develop clinical prediction algorithms to discriminate dengue from other febrile illnesses, and severe dengue from mild dengue. They also reveal the importance of understanding neighborhood-level factors in targeting community-based programs to prevent dengue.

Advisor: Reingold, Arthur
Counting and Correlation Decay in Spin Systems

Spin systems originated in statistical physics as tools for modeling phase transitions in magnets. However, they have since been used to model complex systems arising in several other fields of study (e.g., in Bayesian inference and in the theory of social networks), so that various computational problems associated with them have received much attention in the literature. A lot of progress in the study of these problems has relied upon ideas from statistical physics; one example of this interplay has been the discovery of tight connections between the computational complexity of these problems and the phenomenon of phase transitions that many spin systems exhibit. Conversely, algorithmic ideas have also helped in the study of the phase transition phenomenon./nThis thesis presents two lines of work that fit into this theme. The first considers the approximation of the partition function, a pivotal quantity associated with spin systems. Here, we obtain—in various settings—deterministic polynomial time algorithms for approximating the partition function in the so called uniqueness regime, and thus strengthen the algorithmic side of the tight correspondence between phase transitions and the computational complexity of the partition function./nThe second line of work is concerned with the complexity of exact computation of various natural mean observables of spin systems, e.g., the magnetization in the Ising model. We relate these questions to the location of the complex zeros of the partition function, which have been studied in statistical physics because of their connections to the existence of phase transitions, and have been the subject of various celebrated results (such as the Lee–Yang theorem and the Heilmann–Lieb theorem). By proving a novel extension of the Lee–Yang theorem, we show that the magnetization of the ferromagnetic Ising model is indeed as hard to compute as the partition function (i.e., #P–hard). We also obtain similar results for the monomer–dimer model.

Advisor: Sinclair, Alistair
Spectroscopy, fundamental symmetry tests and quantum simulation with trapped ions

This dissertation reports on precision measurements of the atomic structure of calcium ions (40Ca+), application of trapped 40Ca+ ions as a probe for a violation of fundamental symmetry and prospects of performing quantum simulations with trapped ion./nWe demonstrate a novel technique to perform spectroscopy on the dipole transition of 40Ca+ that circumvents usual difficulties from dark resonances and Doppler heating. The center of the atomic transition can be detected to a precision of 200 kHz or less with an integration time of 10 minutes. We apply this method to directly measure the influence of micromotion on the fluorescence spectra and confirm the dependence of the modulation index on the radial trap frequency./nWe measure the branching fraction of the excited 2P1/2 state of 40Ca+ to be 0.93565(7) using a simple experimental scheme readily applicable to many other ion species. Our result for 40Ca+ distinguishes well among various theoretically calculated values, which is important in guiding further developments of the theoretical work./nWe apply the Ramsey spectroscopy technique based on a pair of correlated ions to probe the effect of the violation of local Lorentz invariance (LLI). The energy difference between the two components of the Bell state |PsiB> = |mJ=5/2,mJ=-5/2>+|mJ=1/2,mJ=-1/2> in the D5/2 manifold of 40Ca+ is monitored for 12 hours. We found that the energy component related to the violation of LLI varies less than 17±22 mHz. Assuming a hydrogen-like model of 40Ca+, the measurement result provides us the bound of the LLI parameter C(2)0 to be 1.7±2.2x10-17./nBased on numerical simulations, we show that the Aubry transition in the Frenkel-Kontorova model with trapped ion can be observed for practical experimental parameters such as the strength and wavelength of the optical lattice, which serves as an external perturbing periodic potential. Moreover, we also show that the normal mode structure of ion chain can change significantly as we vary the strength of the optical lattice.

Advisor: Haeffner, Hartmut
Pubertal Maturation, Sensation Seeking, and Socio-Affectively Motivated Behavior: Investigating Developmental Contributors to Risk-Taking Tendencies

This research examines some of the developmental processes that may help to explain risk-taking tendencies in adolescent girls. In particular, I investigated key aspects of a social and affective neuroscience theory of adolescence in which pubertal development predicts an increased appetitive drive for exciting affective experiences and for social admiration. Participants were 63 girls ages 10-14 (Mage = 12.74) who participated in laboratory measures and completed at-home saliva sample collection. The Pubertal Development Scale (PDS) and basal hormone levels (testosterone, estradiol, DHEA) measured pubertal maturation. Overbidding on a modified Auction Task for adolescents captured socio-affectively motivated behavior at the expense of strategic decision making. Sensation seeking, impulsivity, and resistance to peer influence were assessed via self-report. Covariates were age, verbal intelligence, and socioeconomic status. PDS predicted sensation seeking; PDS, testosterone, and sensation seeking each predicted overbidding on the Auction Task. Sensation seeking was least predictive of overbidding on the Auction Task at low levels of resistance to peer influence. In addition, PDS, testosterone, sensation seeking, and impulsivity were each associated with persistent overbidding over the course of the Auction Task. Results provide additional evidence for the association between pubertal development and sensation seeking, and highlight pubertal adolescent girls' drive for the affective experience of gaining social status. Results also suggest an association between pubertal maturation and the persistence of socio-affectively motivated behavior (perhaps due to social reinforcement learning), with patterns of nonstrategic decision making that otherwise would appear irrational. This research contributes to our understanding of the developmental underpinnings of both prosocial and problematic real-world risk behavior.

Advisor: Hinshaw, Stephen P
Molecular Mechanisms of Itch Signaling in Keratinocytes

There is accumulating evidence suggesting that keratinocytes, the predominant cell type in the skin, may play a key role in the transduction of several somatosensory modalities, including itch. Keratinocytes are activated by a number of itch compounds and release a variety of molecules associated with itch. Additionally, itch-transducing neurons terminate as free nerve endings in the keratinocyte layer of the skin, which would permit rapid keratinocyte-neuron signaling. Our work has focused on two areas: 1) defining the molecular mechanisms by which the atopic dermatitis cytokine TSLP is released from keratinocytes and act on neurons to cause itch and 2) identifying the distinct mechanisms by which histamine and protease signaling in keratinocytes triggers itch./nPrevious studies have shown that activation of the Protease-Activated Receptor 2 (PAR2) leads to upregulation of TSLP in keratinocytes and that TSLP overexpression in keratinocytes induces chronic itch in mice. We characterized the mechanisms by which PAR2 activation leads to TSLP expression and secretion, and elucidated the mechanisms by which secreted TSLP in the skin leads to itch. Understanding the molecular mechanisms underlying atopic dermatitis may identify targets that could lead to the development of drugs that specifically block atopic dermatitis itch while leaving other somatosensations intact./nPrevious studies have linked histamine and protease signaling to distinct clinical itch phenotypes; histamine signaling is associated with allergic itch, while protease signaling is associated with atopic dermatitis. Histamine and PAR2 agonists activate the same population of keratinocytes, thus how these pruritogens trigger distinct itch pathologies was unknown. We now demonstrate that histamine and protease signaling in keratinocytes induce distinct calcium signals that lead to divergent downstream transcriptional outputs.

Advisor: Bautista, Diana
Photochemically Inspired Oxidative Coupling Reactions with Application in Light Harvesting and Bioconjugation

The development of new tools to modify biomolecules is critical in the field of chemical biology to the development of novel techniques and materials. The increased complexity of the desired systems necessitates further regulation over how and where those modifications take place. To do so, there is a need for new scaffolds and reactions that enable spatial control and reaction simplicity in addition to the high efficiency and speed provided by existing reactions. This work elaborates on the development of new scaffolds to use, in addition to reactions that allow for those increased levels of control. An inspiration that guided much of this research is the precision and energy afforded by light. Using principles of photochemistry, progress was made to providing photobleaching protection to a light harvesting system developed in the lab. To further expand the potential of that system for new applications, the underlying scaffold - tobacco mosaic virus - was modified to incorporate a new reactive handle at its bottom face. The use of the oxidative coupling reaction of ortho aminophenols with periodate led to the development of a light-triggered and spatially controlled reaction that enabled the patterning of substrates on surfaces. The use of an oxidant in this reaction also led to the development of a shelf stable alternative to the easily oxidized aminophenol required for oxidative coupling.

Advisor: Francis, Matthew B
Homomorphisms between groups of diffeomorphisms

The main results of this dissertation concern the structure of the group of diffeomorphisms of a smooth manifold. Filipckiewicz's theorem states that two manifolds M and N have isomorphic diffeomorphism groups (isomorphic as abstract groups) if and only if the manifolds M and N are diffeomorphic. We give a new proof of Filipckiewicz's result and establish a generalization of it by showing that any non-trivial abstract homomorphism between groups of diffeomorphisms is in some sense continuous. The proof of our results are related to the concept of distortion in geometric group theory, concept which has proven to be useful for the study and classification of certain group actions on manifolds. We also give new dynamical restrictions that certain type of distorted elements in diffeomorphism groups known as ``arbitrarily distorted" must have.

Advisor: Agol, Ian
Improving Bus Service with Dynamic Holding Control: from Theory to Practice

Service unreliability is widely recognized as one of the main deterrents for travelers to use buses as their primary mode of transportation. Bus systems are exposed to an adverse feedback loop that generates a tendency for buses to fall out of sync. This tendency can be counteracted by the application of control strategies that regulate the motion of the buses. Even though this is well known among transit operators and research has been devoted to solve this issue, in practice most bus systems rely on static control methods that ignore the real conditions of the system. Unfortunately, such an approach slows buses down excessively and it cannot compensate for severe disruptions./nThis research proposes a control method that applies dynamic holding based on real-time conditions, in order to synchronize the buses' motion and improve their service reliability without imposing an excessive burden on their speed. A formulation that improves and simplifies existing dynamic holding control strategies for isolated bus lines is developed. Stability conditions both for headway and schedule deviations are then derived, and the theoretical results are validated with a simulation case study. The improved formulation is then extended to corridors where multiple bus lines overlap, reproducing the stability results found in the single line scenario. A framework for a real application entailing a distributed system of on-board devices is also presented. The control performance is then validated, now using a real-world case study. Finally, the robustness of this control framework is assessed considering the effects of possible device failures. In particular, the effects of GPS malfunctions on the on-board devices are studied analytically, revealing the resilience of the proposed control strategy.

Advisor: Daganzo, Carlos F
Towards High Assurance HTML5 Applications

Rich client-side applications written in HTML5 proliferate diverse platforms/nsuch as mobile devices, commodity PCs, and the web platform. These client-side/nHTML5 applications are increasingly accessing sensitive data, including users'/npersonal and social data, sensor data, and capability-bearing tokens. Instead of/nthe classic client/server model of web applications, modern HTML5 applications/nare complex client-side applications that may call some web services, and run/nwith ambient privileges to access sensitive data or sensors. The goal of this/nwork is to enable the creation of higher-assurance HTML5 applications. We/npropose two major directions: first, we present the use of formal methods to/nanalyze web protocols for errors. Second, we use existing primitives to enable/npractical privilege separation for HTML5 applications. We also propose a new/nprimitive for complete mediation of HTML5 applications. Our proposed designs/nconsiderably ease analysis and improve auditability.

Advisor: Song, Dawn