VictorJuiz/thesis huggingface dataset:
From intuition and code to score [electronic resource] : modeling musical output
Keywords: Music.

This D.M.A. dissertation consists of a portfolio of four musical works: Areas (for chamber orchestra), Torcal (for great organ), Gotlhar (for chamber ensemble), and Seco (for two pianos and two percussions). These pieces are the compositional application of my research on computational generative models of music material. One substantial idea during the writing of these compositions is that of formalizing the structure and organization of musical events with the aid of programmable algorithms. A common procedure for the composition of these works observes the Sensory Dissonance Curve model proposed by William Sethares. This model establishes a relationship between the spectrum of a sound and a tuning system in which the timbre of the former will appear most consonant (or dissonant otherwise) to a given scale configuration. The reversal process of defining timbral qualities of sounds given arbitrary scale/tuning fields is also possible. 'Dissonance-curve' scales and tunings defined by specific instrumentations (via their spectra), are subsequently mapped to harmonic/inharmonic chord configurations, whose ratio proportions determine the local rhythmic patterns and the durations of the large-scale form of the pieces. To facilitate the translation of the 'sensory dissonance curve' model and its subsequent mappings into music scores with a high level of notational/symbolic expressivity, I have developed Xa-Lan, a computer program written in Common LISP that uses the 'Expressive Notation Package' of PWGL for final output.
From MIT to Paraguay [electronic resource] : a critical historical and ethnographic analysis of one laptop per child
Keywords: Communication.

One Laptop Per Child (OLPC) represents one of the largest experiments in laptop-driven learning currently underway. Since its founding in 2005, OLPC has been promoting their custom-designed green and white "XO" laptops as a solution for learning and economic growth in the developing world. About two and a half million of these laptops are in use -- 85% of them in Latin America -- and the project has inspired other initiatives in both education and low-cost computing. The XO has become a focal point for diverse and sometimes contradictory discourses about children, technology, education, and development, bringing unlikely groups into conversation around this charismatic object. OLPC and the educational philosophy that inspired it, constructionism, both hailing from the MIT Media Lab, frame themselves as a radical break from unchanging educational tradition. I first explore what the laptops developers intended it to do through a reading of literature about the laptop and the features of the laptop itself. I then compare these intentions with what the laptop is actually doing in a small but well-supported project of 9000 laptops in Paraguay, based on six months of ethnographic fieldwork. In the process, I examine the role that a utopian framing plays in evangelizing OLPC and in making the XO laptop a charismatic object on one hand, and limiting its integration into the messy realities of day-to-day use on the other. In closely examining the ideas built into OLPC's laptops and the ways in which children actually use the machines, my research sheds light on the complicated and often contentious debate over the symbolic and actual role of technology in childhood, education, and development.
Fundamental analysis and equity volatility [electronic resource]
Keywords: Business.

I examine whether financial statement information can predict future realized volatility incremental to the volatility implied by option market prices. Prior research establishes that option-implied volatility is a biased estimator of future realized volatility. I hypothesize that financial statement information, by providing information about economic events correlated with future volatility, is informative in the prediction of future volatility and not fully incorporated in either past volatility or the market's expectation of future volatility. I confirm this empirically and show that the finding is robust to the measurement of option-implied volatility using either the Black-Scholes formula or a model-free approach. I also document abnormal returns to an option-based trading strategy that takes a long (short) position in firms with financial statement information indicative of high (low) future volatility. Additionally, I provide evidence that contradicts a risk-based explanation for the incremental predictive ability of accounting information. Taken together, my results indicate that the market's failure to fully process accounting-based fundamental information explains some of the previously documented bias in implied volatility.
GaAs-based 1550 nm GaInNAsSb lasers [electronic resource]
Keywords: Electrical Engineering.

Low-cost, long-wavelength light sources are indispensable for the widespread deployment of fiber-to-the-home networks. Vertical cavity surface emitting lasers (VCSELs) are ideal for these applications due to their high fiber-coupling efficiency, low power consumption, simple packaging and wafer-scale manufacturability. In particular, VCSELs emitting in the C-band (1530-1565 nm) are highly desirable given that the fiber optical loss is minimal in this wavelength range. High-performance 1550 nm InP-based VCSELs using various distributed Bragg reflector (DBR) technologies have been demonstrated, but these approaches generally require complex and extensive processing, leading to high manufacturing costs. In contrast, GaAs-based VCSELs can be processed in a simple and robust way by exploiting the superior material properties of Al(Ga)As/GaAs DBRs and the oxidation of AlAs layers for electrical and optical confinement. Dilute nitride GaInNAsSb alloys emitting in the 1200-1600 nm wavelength range can be grown coherently on GaAs substrates, enabling the realization of long wavelength GaAs-based lasers. Despite significant challenges in the growth of such highly-mismatched alloys, 1550 nm GaInNAsSb lasers with relatively low threshold current densities have been demonstrated. This dissertation describes recent progress on the development of GaInNAsSb lasers. Optimization of the growth and annealing conditions enabled a four-fold enhancement of the luminescence efficiency of GaInNAsSb quantum wells with GaNAs barriers. In addition, incorporation of GaAsP barriers significantly improved the temperature stability of the lasers. The improved quantum wells enabled the realization of the first electrically-pumped GaInNAsSb VCSELs emitting in the C-band that operate at and above room temperature.
Gas-phase reaction dynamics [electronic resource] : from billiard balls to geometric phase in H + H2
Keywords: Chemistry.

Hydrogen exchange reaction, the simplest chemical transformation, has been studied experimentally by measuring the angular distributions of the H + H2 → H2(v', j') + H reaction products, that were detected with v' and j' state specificity. Although the expected behavior is observed -- wherein the H2 products scatter into a more sideway direction with increasing rotational excitation of the hydrogen product -- we have also uncovered a previously unseen trend, wherein the H2 reaction products scatter into a more backward direction with increasing j', i.e. the opposite behavior to the expected one! In addition, certain rotationally cold products of the H + D2 → HD(v' = 2, j' = 0) + D reaction at a center-of-mass collision energy of 1.25 eV are forward-scattered due to a time-delayed mechanism. Finally, an attempt has been made to measure the theoretically predicted Geometric Phase effects in the H3 system. To this end, a reaction where 'nothing happens' has been studied, namely H + HD → HD(v', j') + H, because the sole Geometric Phase effect is to change the sign in front of the oscillatory term that describes the interference between the experimentally indistinguishable reactive and inelastic scattering pathways. Fine out-of-phase oscillations calculated theoretically have turned out to be beyond the experimental resolution.
Generalized polylogarithms in perturbative quantum field theory [electronic resource]
Keywords: Physics.

This thesis examines the mathematical structure of scattering amplitudes and correlation functions in perturbative quantum field theory. The focus is on maximally supersymmetric N=4 super Yang-Mills theory, though the techniques presented here should be applicable in other contexts as well. Multi-loop Feynman integrals typically do not evaluate to classical functions, but in many cases they can be expressed in terms of certain types of iterated integrals that generalize classical polylogarithms. I show throughout this thesis how certain analytic properties of these functions can be used in conjunction with physical constraints to produce highly efficient methods of calculation. In the first half of this work, I focus on quantities in N=4 super Yang-Mills theory that can be expressed in terms of polylogarithmic functions of two variables, presenting results for the multi-Regge kinematical limit of six-point amplitudes and for the four-point correlation function of stress-tensor multiplets. In the second half of this work, I extend the analysis to functions of three variables in order to calculate the six-point remainder function, which describes the scattering of six gluons in planar N=4 super Yang-Mills theory. I present analytical results for the remainder function at three and four loops.
Generous purpose during early adolescence [electronic resource] : the roles of school generosity and relational spirituality
Keywords: Education.

Purpose, especially in its generous form, may serve as a critical catalyst on the path to thriving for adolescents. However, while there is a growing amount of research about purpose, less of it focuses on ways in which purpose might be supported by both individual and contextual variables. Spirituality and schools are two such variables. The primary hypotheses of this study posited that both school generosity and relational spirituality would positively predict generous purpose. The secondary hypotheses of this study are better understood as exploratory. Specifically, I hypothesized that some relation would be found between school generosity and relational spirituality, but did not speculate about the exact nature of this relation. I also hypothesized that the spiritual context of the school would be associated with differences in relations among school generosity, relational spirituality and generous purpose, but did not speculate about the specific nature of those differences. In order to test these hypotheses, survey data was collected from ninth grade students (n = 253) at three high schools of varying stated spiritual contexts twice during the ninth grade year. The schools included a Catholic school, a Waldorf-methods school, and a community-centered charter school. Correlation and linear regression analysis led to the following results. School generosity among students and relational spirituality were both shown to be statistically significant, positive predictors of generous purpose in ninth grade students. In addition, school generosity and relational spirituality were also related to each other. First, school generosity was shown to predict relational spirituality. Second, when both were included in a regression equation predicting generous purpose, only relational spirituality remained a significant predictor of generous purpose. School-level results were more mixed, with only weak evidence found for the role of the spiritual context of the school. These results are interpreted in a positive youth development framework, pointing to the importance of peers and of school environments that provide a good fit for early adolescents. Implications for both PYD theory and education are discussed.
Genetic probing of the origin of alveolar myofibroblasts and bronchopulmonary dysplasia, a disease of alveolar development [electronic resource]
Keywords: Biochemistry.

Alveolarization, the final stage of lung development, promotes gas-exchange by dividing the sac-like terminal airspaces of the lung into thin-walled pockets. Myofibroblasts are found at sites of septation, and mouse mutants in PDGFR alpha signaling lack myofibroblasts and air sacs fail to septate, suggesting that myofibroblasts play a role in septation. Further, a similar arrest in alveolarization is observed in diseases like bronchopulmonary dysplasia (BPD), a disease of premature infants that twin studies implicate may have important genetic contributions. In this thesis, I explore the developmental origins of myofibroblasts in mouse and the genetic basis of BPD. I first describe a novel protocol developed to extract DNA from dried blood spots taken from newborn infants that can be used in genotyping and genome-wide association studies (GWAS). I then describe an agnostic exploration of the genetic basis of BPD. Finally, I describe the use of genetic lineage tracing in mice to identify airway smooth muscle cells as a source of ductal myofibroblasts during lung development.
A genome-wide siRNA screen identifies a novel, 7 transmembrane protein that mediates amino acid signaling to mTORC1 [electronic resource]
Keywords: Chemical and Systems Biology.

Cells have an evolutionarily conserved mechanism to sense and integrate nutrient information for optimal growth and survival. The signaling network that is central to receiving nutritional inputs and translating them to effects on anabolic and catabolic activities of the cell consists of a large serine/threonine kinase known as mTOR. mTOR signaling is crucial for many important cellular processes such metabolism, growth, proliferation and differentiation. It is able to integrate diverse inputs including growth factors, cytokines, energy, oxygen and stress in addition to nutrients and regulate diverse outputs including translation, ribosome biogenesis, lipid biogenesis and autophagy. It is also an important therapeutic target and its inhibitor Rapamycin is currently being used or tested for a wide range of diseases including cancers and neurodegenerative diseases. Amino acids are arguably the most important regulators of mTOR and a long standing mystery in the field is the identity of the amino acid sensor and the mechanism of sensing. Using RNAi, we systematically screened through the human genome for candidate genes regulating amino acid signaling. We confirm that the mitochondria and the lysosomes are the two key sensing organelles, with amino acid metabolism and the RagGTPases being important for signal transduction. We identify a novel lysosomal 7 transmembrane protein that mediates signals upstream the RagGTPases and binds mTORC1-RagA in an amino-acid dependent manner. We also demonstrate that increasing levels of this protein enables cells to recruit mTOR to lysosomes and activate its kinase activity in the absence of amino acids. We show that GPR137B, mTORC1 and RagA form an amino acid sensitive, high-affinity binding complex at the lysosome. We propose a model of sensing where the 7-transmembrane protein, which we renamed to MORTOR, forms a tight complex with mTORC1-RagA in the presence of amino acids, resulting in the persistent lysosomal recruitment and activation of mTORC1. In addition to identifying novel regulators, this systematic study has also generated testable hypotheses about systems level properties of mTORC1 signaling, thus providing the foundation to understand mTOR signaling as a network. The discovery of the novel 7 transmembrane protein and its GPCR-like characteristics also has the potential to lead to new classes of therapeutics and targets for this important pathway.
A geostatistical approach to quantifying rainfall uncertainty in Southern Africa using terrain characteristics [electronic resource]
Keywords: Civil and Environmental Engineering.

Rainfall is the most important driver of hydrologic response predicted by models. By improving estimates of rainfall, improved estimates of streamflow may be possible. There has been little comprehensive research regarding the relative importance of ancillary terrain data for improving rainfall estimates. This research focuses on using geostatistical techniques to generate improved rainfall estimates using gridded ancillary terrain data. In addition, a geostatistical approach is used to estimate ensemble rainfall fields, which could be used to stochastically drive a rainfall-runoff model. The field sites for this research are (1) the 31,200 sq km Inkomati Water Management Area (IWMA) in northeastern South Africa, and (2) the more data-sparse 185,100 sq km Central-North Regional Water Administration (ARACN) in Mozambique. Monthly rainfall data for the year 1970 were analyzed. This study found that, for this time period, the most important pieces of ancillary data for improving the estimation of rainfall fields in IWMA and ARACN are elevation (20km resolution) and slope. Distance to long-term annual rainfall maximum and distance to coast also helped to improve rainfall estimation.
Germanium-tin (GeSn) Technology [electronic resource]
Keywords: Electrical Engineering.

Semiconducting germanium-tin (GeSn) alloy is a versatile material system that is attracting significant research interest due to its several unique and beneficial properties, such as the ability to show a direct band gap and the compatibility with conventional Si technology. GeSn alloy system is also predicted to exhibit high electron and hole mobilities, making it an ideal material platform for co-integration of Si compatible photonics and high speed CMOS devices. This thesis discusses a very broad range of topics pertinent to GeSn, beginning with a detailed theoretical study of electronic properties of GeSn using both first principles and empirical methods. Challenges in obtaining high quality epitaxial GeSn thin films are addressed. Innovations in GeSn material processing and device fabrication are presented. Applications of the GeSn technology thus developed to high performance logic devices, Si-compatible photonics and 3-dimensional integrated circuits are discussed.
Global Ends and Local Means: Lessons about Filipino Youth Activism and Civic Engagement in Anakbayan
Keywords: civic engagement
Filipino
youth
Anakbayan
social change
youth movement
community organizing
Thesis

This study sought to explore what participants learned and valued about civic engagement through their involvement with Anakbayan, a Filipino youth-led, grassroots organization that fights for the welfare of its local communities as well as the need for genuine social change and democracy in the Philippines. With such a unique group operating within the context of the United States, the research aimed to explore what members’ experiences might contribute to contemporary understandings of civic engagement. The study found that members gained a greater awareness of both their civic identity and civic context, most typically shown by how members located themselves and their experiences within the group’s political discourse (i.e., how they saw themselves in relation to the issue of immigration). Moreover, members also gained new means of imagining and constructing community within the context of a specific type of community organizing. Members adapted a notion of community that included both local and global contexts which then influenced how they approached taking action and engaging with Anakbayan’s larger civic mission. Variation occurred based on the degree to which participants demonstrated internalization of the relationship between local and global contexts.
Green-Marl [electronic resource] : a domain specific language for graph analysis
Keywords: Electrical Engineering.

Graph is a fundamental data structure that captures arbitrary relationship between data entities. In recent years, the importance of efficient and scalable processing of large graph instances has been growing due to emerging applications such as social network services and computational biology, where large graph data-sets are heavily used. Fortunately, recent proliferation of parallel (e.g. multi-core CPUs and GPUs) and distributed (e.g. Amazon's EC2) computing environment has provided ways to exploit inherent parallelism in large graph data processing. However, it is still burdensome for a single programmer to implement graph algorithms correctly and efficiently while exploiting parallelism in a different way for each parallel or distributed environment. In this thesis, we present how this burden can be lightened up by the means of a Domain-Specific Language (DSL). First, we introduce Green-Marl, a domain specific language which allows the users to program their graph algorithms in an intuitive manner. However, the language is also designed in such a way that the underlying data-parallelism in the given graph analysis program is easily exposed to the Green-Marl compiler. Then, I will explain how the compiler can exploit such high-level semantic information to optimize the given user algorithm and to produce an efficient parallel implementation out of it. Experimental results show that the compiler-generated codes are as efficient as hand-coded versions in parallel graph libraries. Next, we explain how the Green-Marl compiler can produce an implementation for a distributed environment from the same Green-Marl program. Again the Green-Marl compiler uses high-level semantic knowledge to transform the given Green-Marl program into another one which is based on completely different programming model. Again the performance of compiler-generated code closely matches with hand-coded version. In summary, I show that the Green-Marl DSL can provide benefits of productivity, performance and portability to the users in the domain of large graph analysis.
The group-lasso [electronic resource] : two novel applications
Keywords: Statistics.

In the first application, we introduce a method for learning pairwise interactions in a manner that satisfies strong hierarchy: whenever an interaction is estimated to be nonzero, both its associated main effects are also included in the model. We compare our method with existing approaches on both simulated and real data, including a genome wide association study, all using our R package glinternet. The second application is about recovering neural source activity in the visual cortex using non-invasive electroencephalography (EEG) recordings from sensors placed around a subject's head. We show that the group-lasso outperforms the widely-used minimum norm inversion, and that the group-lasso performance improves with the number of subjects. We also show that averaging the estimated source activity within appropriately defined regions of interest (ROIs) in the visual cortex across multiple subjects is able to dramatically boost the performance of both the minimum norm and group-lasso solutions, and also improves with the number of subjects.
G-valued flat deformations and local models [electronic resource]
Keywords: Mathematics.

We construct resolutions of G-valued local Galois deformation rings by moduli spaces of Kisin modules with G-structure when l = p. This generalizes Mark Kisin's work on potentially semi-stable deformation rings. In the case of flat deformations, we prove a structural result about these resolutions which relates the connected components of G-valued flat deformation rings to the connected components of projective varieties in characteristic p, which are moduli spaces of linear algebra data. As a key step in the study of these resolutions, we prove a full faithfulness result in integral p-adic Hodge theory. We also generalize results of Pappas and Zhu on local models of Shimura varieties to groups arising from Weil restrictions.