VictorJuiz/thesis huggingface dataset:
Computational electromagnetics for nanophotonic design and discovery [electronic resource]
Keywords: Electrical Engineering.

Computational electromagnetics has become an essential tool for designing nanophotonic devices. While there exist many general purpose computational methods, we show that tailored approaches can be dramatically faster for solving design problems requiring millions to billions of iterations. In the first half of this dissertation, we describe a particular method designed for photonic crystal structures, and apply it to the design of extremely compact aperiodic devices such as wavelength division multiplexers, waveguide mode converters, and multimode waveguide bends. Next, we describe the Fourier Modal Method (FMM), a computational technique designed for layered periodic structures. We extend the method by deriving new formulations for the mode expansions, and demonstrate its improved accuracy and discuss its applicability for modeling structures with metals. Finally, the FMM is applied to investigate optical forces in coupled photonic crystal slabs. We demonstrate the role that optically bright and dark resonances play in the enhancement of optical forces.
Computationally guided drug repurposing as a drug development strategy [electronic resource]
Keywords: Chemistry.

The pharmaceutical industry is experiencing unprecedented financial pressures and unsustainable research expenditures, threatening to compromise the robust development of new therapies. In response many pharmaceutical companies and translational research organizations have invested heavily in new technologies promising more efficient and productive research, including high-throughput screening, combinatorial chemistry for compound library generation, genetics and pharmacokinetics, and many others. Unfortunately these technologies have largely failed to significantly increase the efficiency of pharmaceutical research, as evidenced by the steady increase in research dollars required per new approved drug (currently estimated at nearly
Conjugated polymer sorting of semiconducting nanotubes and their electronic applications [electronic resource]
Keywords: Materials Science and Engineering.

Single-walled carbon nanotubes (SWNTs) have excellent electrical properties for a wide range of applications such as transistors, solar cells, photodetectors and chemical/biologic sensors. However, for all these applications, it is necessary to separate semiconducting SWNTs from metallic ones. Sorting SWNTs using conjugated polymers has been demonstrated to be a simple and low-cost method to effectively sort large quantities of semiconducting SWNTs. In this thesis, I first describe how semiconducting SWNT sorting can be improved by judiciously considering polymer design and solvent effects. A mechanism for the selective dispersion of semiconducting SWNTs is also proposed. As a result of improved semiconducting SWNT sorting, the application of SWNTs in printed transistors, solar cells and logic circuits is made possible. In particular, high-mobility, high on/off ratio transistors from the sorted semiconducting SWNTs are achieved. Then, I explain the development of n-type molecular doping and fluorinated dielectrics to control the threshold voltage of SWNT transistors as well as to improve the bias stability of the devices under ambient conditions. These advancements allow the fabrication of the first flexible SWNT complementary logic circuits with high reliability (high noise margin) and low power-consumptions. Finally, I discuss a novel technique to conform the shape of flexible SWNT electronics into 3-dimensional objects by utilizing shape memory polymers. The technique also allows conformal coating of the SWNT transistors and sensors to any irregular shaped-objects without degradation of device performance.
Constraints on the form and formation of branched channel networks [electronic resource]
Keywords: Geological and Environmental Sciences.

This thesis focuses on the form and formation of Branched Channel Networks (BCNs). These networks are among the most striking forms that define the surface of our planet, and are the primary means that transport rock and water from high to low elevations across Earth's surface. As such, they play a fundamental role in shaping the elevation structure of continents, the spatial distribution of vegetation, and the rates and routes by which rocks, nutrients, and water are transported across different terrestrial reservoirs. BCNs also exist in extraterrestrial environments, where, as on Earth, they may encapsulate information regarding the processes and physical conditions under which these environments are shaped. In studying these networks, I pose two main hypotheses: (a) the structure of BCNs is sensitive to the erosional mechanics of the processes that carve them, and (b) a common set of constraints rationalizes the ubiquity of BCNs across disparate physical conditions (e.g., subaerial, submarine, extraterrestrial). First, I evaluate the limitations of the numerical tools with which I test these hypotheses, and show that the flow-routing rules used for the downslope routing of water and sediment over gridded Digital Elevation Models (DEMs) have a statistically significant impact on the form of modeled topography and the spatial distribution of modeled geomorphic processes. Having these limitations in mind, I address the first hypothesis, and show that the structure of BCNs reflects two coupled constraints: (1) the characteristic along-flow channel profile shaped by the channel forming processes, and (2) the fact that two flows initiating at an infinitesimal distance apart on each side of a drainage divide must experience an identical elevation drop between the divide and the junction where these flows once again meet. I then use numerical Landscape Development Model (LDMs) and analysis tools to demonstrate that these constraints impact the plan-view structure of BCNs as well as their temporal evolution, and that the form of these networks is indeed sensitive to the erosional mechanics of the processes that shape them. To address the second hypotheses, I analytically show that a simple dependence between sediment transport rate and the frequency at which geophysical flows traverse landscapes rationalizes the formation of BCNs by a wide variety of process, regardless of the stochasticity or homogeneity in which these processes are generated in time and/or space. Thus, as long as this dependency exists, networks may form by a variety of processes across disparate physical conditions. I then use LDMs based on this analytical framework to demonstrate the conditions for network formation and the relationships between the physical characteristics of flows and the landscape features they form.
Constructing novel, genetically encodable tools to study the role of actin in developmental myelination
Keywords:  Department of Biology
Biology
Neurobiology
Cell Biology
Thesis

The insulating myelin sheath formed by oligodendrocytes is crucial for rapid conduction of action potentials. The understanding of how oligodendrocytes wrap this specialized membrane is limited. Actin, a key regulator of cell structure and movement, is hypothesized to play an important role (Bauer et al., 2009). Further investigation of the role of actin in myelination necessitates a cell-specific tool with fine temporal and dose- dependent control. We developed genetically encodable actin-modifying tools (gACTs). Using DNA sequences from endogenous actin-modifying proteins or bacterial toxins allowed us to harness their actin modifying power. At this stage, the constructs allow for temporal control and either dose-dependent or cell-specific control, but ultimately the tool will have all three features. To validate the constructs, we transfected HeLa cells and visualized actin morphology. We found clear actin morphology changes upon transfection for all five constructs with variable effectiveness and cytotoxicity. To provide temporal and dose-dependent control, we fused the destabilization domain (DD) to the constructs (Banaszynski et al., 2006). To provide temporal control and cell specificity, we replaced the strong cytomegalovirus (CMV) promoter with a myelin basic protein (MBP) promoter, conferring expression only in mature stages of oligodendrocytes. In addition to elucidating the role of actin in myelination, gACTs are a useful general cell biology tool to study actin in multicellular processes such as development or diseases such as multiple sclerosis.
Contemporary Women in Romantic Contexts: Time-travel Period Dramas as Didactic Cultural Productions
Keywords:  Program in Feminist
Time travel
period drama
feminist studies
Chinese women
contemporary Chinese women's issues
female homosociality
women and television
Chinese television
female success
Palace
Lost in Austen
Janeites
Thesis

Time-travel period dramas, as defined by much of the popular discourse, refer to a kind of costume drama that entails a modern character traveling into the past and taking up a dramatic journey of both romance and personal growth. In this thesis, I study Chinese and Western time-travel period dramas from a feminist perspective. In chapter 1, I discuss the theme of escape as central to time-travel period dramas. Escape functions to criticize women’s conditions in the present and offer a way to leave behind the unsatisfying lifestyles led by the female protagonists. Escape also works as exile, at least in Palace, a compulsory means to punish and educate. This is because it also presents an opportunity for these protagonists to undergo a journey that promises the resolution of those problems with which they struggle at the beginning of the show. In chapter 1, I hope to set up the didactic nature of time-travel period dramas by virtue of its promise to present “solutions” at the end of the shows. In chapter 2, I will observe what defines feminine success in each of the shows. To do this, I will first observe the competitive female homosocial space in Palace and argue why it creates a kind of feminine success that require “beating” other women. This conclusion is drawn with comparison to the cooperative and friendly female homosocial space in Lost in Austen, where the protagonist’s path to happiness is not mutually exclusive with that of the other female characters. Ultimately, I hope to show that an important mode of feminine success in Palace has to do with the manipulation of men, whereas feminine success in Lost in Austen revolves around internal struggles of self-understanding. In chapter 3, these analyses culminate in an examination of the endings of the show, which present the dilemma of staying or leaving the ideal mate/ the past. This is where I will account for most of the tension in study “feminism” across cultures and societies by diving into a deeper exploration of different strategies of interpreting a text. With regard to the Western text, Lost in Austen, I believe that its solution to women’s problems in modern society take on a radical postfeminist message, preaching the freedom of choice without moral, social historical qualifications. In turn, I will argue that the ending of Palace presents a kind of socially subversive narrative by breaking out of the Chinese post-Revolutionary, liberation narrative and confronting the continuity of women’s oppression.
Contributions to reducing greenhouse gas emissions using computationally evolved lens designs and organic electronics [electronic resource]
Keywords: Electrical Engineering.

The need for reducing greenhouse gas emissions and generating energy from renewable sources is more crucial now than ever before. This has now become imperative because the planet is on the verge of a tipping point with regards to the effects of greenhouse gases on the average temperature of the earth. The work described in this thesis is divided into two parts. The first facilitates the adoption of more renewable energy generation methods, specifically concentrated photovoltaics, in which nonimaging lenses for solar concentration are used. Genetic algorithms will be utilized as a way of designing and evolving such novel shaped lenses with a high half acceptance angle. Two main categories of lenses will be highlighted; the first with a uniform material composition and the second with a gradient refractive index along one and both axes of the lens. The details of the genetic algorithm and operators developed and designed for this purpose will also be discussed. In the second part of the thesis, the emphasis is on creating thin film organic based electronics. These organic electronics are also lightweight, flexible and can be stretched to cover large surface areas. Many applications benefit from thin film embedded electronics such as carbon fiber composite structures. This new kind of smart electronics integrated within composite materials can help in significantly slashing the emissions of greenhouse gases in the transportation sector. This is especially the case in high emissions transport vehicles such as air planes. Light weight, low emissions aircraft that are also safe because of the redundant smart electronics within their design make them more adoptable.
A convex-programming framework for super-resolution [electronic resource]
Keywords: Electrical Engineering.

This thesis proposes a general framework to extract information from low-resolution data, a crucial challenge in applications ranging from microscopy, astronomy and medical imaging to geophysics, signal processing and spectroscopy. Assume that we only have information about the spectrum of a superposition of point sources in the low-frequency band $[-f, f]$. We show that as long as the sources are separated by 2/f, solving a simple convex program achieves exact recovery, in the sense that the original signal is the unique solution to the optimization problem. This is established by leveraging a novel proof technique which constructs a dual certificate by interpolation. In addition, we describe how to implement the recovery algorithm by solving a finite-dimensional semidefinite program, which locates the support of the signal with infinite precision. The guarantees extend to higher dimensions and other models. They imply, for instance, that we can recover a piecewise-smooth function from bandlimited data by super-resolving the discontinuity points. We also provide an analysis of the stability of our method in the presence of noise. On the one hand, we prove that it is possible to extrapolate the spectrum of the original signal up to a frequency F > f to obtain an approximation error between the higher-resolution reconstruction and the truth that is proportional to the noise level times the square of the super-resolution factor (SRF) F/f. On the other hand, we derive support-detection guarantees that quantify the precision with which we can determine the location of each individual point source in the signal.
Copyright and incentive [electronic resource] : a music industry with Chinese characteristics
Keywords: Law JSD.

Copyright law is widely perceived as the means to promote social welfare by providing necessary incentive for intellectual creation. There however has been little consensus in copyright literature how artists actually respond to copyright incentives: What factors motivate artists to create works? How do artists perceive the usefulness of copyright protection? Would artists continue their artistic careers in a world without copyright law? This dissertation reports the empirical evidence on copyright and incentive based on the industrial statistics and extensive interviews in the music industry in China, a virtual copyright-free environment featuring one of the highest piracy rates in the world and having generated dramatic developments of the music businesses. The qualitative research indicates three seemingly paradoxical phenomena: While merely 17.9% of all the musicians in the sample referred to economic benefits as at least part of their motivations for music creation, 97.4% specifically recognized money as being important and helpful for music creation. While 56.4% of all the musicians alleged that copyright piracy does not affect their creative motivations, 72% agreed that copyright piracy does affect music creation. While 53.8% of all the musicians explicitly admitted that they had little awareness or knowledge about copyright, 92.3% indicated that the current level of copyright protection is insufficient and 71.8% suggested that copyright law should provide strong incentives for music creation. The empirical evidence itself provides compelling explanations for such paradoxes: Even though musicians primarily create music for the music's sake, copyright law could still supply powerful incentive for music production in a way that not only caters to market demand but allows for wider artistic freedom. Copyright piracy that does not necessarily affect musicians' intrinsic motivations could nevertheless affect music creation in terms of the time spent on music creation, the volume of investment in music creation and ultimately the quality of music creation. Most importantly, copyright incentives do not function as a reward that musicians consciously bargain for and chase after but as a mechanism that preserves market conditions for gifted musicians to prosper, including a decent standard of living, sufficient income to cover production costs, and maximum artistic autonomy during the creative process.
Coral [delta] 18 O records from Palau and Eastern Island [electronic resource] : contributions to the network of Pan-Pacific high-resolution paleoclimate records
Keywords: Environmental Earth System Science.

Coral-based proxy records are one of the most powerful tools for extending our understanding of interannual to centennial modes associated with El Niño-Southern Oscillation (ENSO) variability. Such records are also crucial for constraining forecasts under various greenhouse gas emission scenarios. In this dissertation I present an examination of records obtained from two study sites: The Republic of Palau (7.5°N 134.5°E) and Easter Island (27°S 109°W). This dissertation is organized into five chapters and an appendix. Chapter 1 is an introduction to paleoclimate, ENSO, and coral-based proxy records. In Chapter 2, I present the analysis of four records from Palau that were sampled from diverse localities within this study region. We take advantage of the multiple instrumental products and previously published results in our evaluation of the Palau coral [delta] 18O ([delta] 18OCRL) signal. Our primary conclusion in Chapter 2 is that Palau [delta] 18OCRL is well suited to capture ENSO, regardless of the coral environmental setting. We also show that Palau [delta] 18OCRL is primarily related to salinity, with temperature exerting a secondary influence. In Chapter 3 we apply our [delta] 18OCRL calibration results from Palau to the pre-instrumental period. Our records exhibit excellent reproducibility over the 20th century, and show strong coherence with other tropical Pacific [delta] 18OCRL records. We identify a 23/24 year cycle which is robust throughout the West Pacific Warm Pool (WPWP) following the end of the Little Ice Age (LIA). The Palau records show a long-term trend indicative of warming and/or freshening. Chapter 4 presents the results of three previously unpublished [delta] 18OCRL records from Easter Island, which resides in a region that is particularly devoid of high-resolution paleoclimate observations. All of the Easter Island corals display complex growth morphology. As a result, we deploy a range of techniques to develop age models. Our chief conclusion is that the Easter Island [delta] 18OCRL records closely follow hemispheric and global scale temperature trends over the 20th century. We also observe unique seasonal trends, which are likely attributable biases in seasonal carbonate precipitation and our age model schemes. Our analyses of the Easter Island [delta] 18OCRL records support the assertion that decadal variability across the Pacific basin originates in the tropics. All of the [delta] 18OCRL records presented in this dissertation represent significant contributions our understanding of Pan-Pacific climate variability over the past two centuries.
Corruption and social norms [electronic resource] : explaining corruption's persistence in the face of moral condemnation
Keywords: Political Science.

This dissertation uses social norms theory to explain why individuals in badly governed societies often tolerate and perpetuate corrupt practices despite simultaneously regarding such behaviors as morally dubious. It is composed of three stand-alone, but related, empirical papers. The first paper argues that the choice between corruption and honesty is a matter of conditional compliance: individuals will abide by norms of integrity when they trust their compatriots to do so as well. I examine the mechanisms underlying stability and change in normative beliefs, focusing specifically on the role of inter-group interactions and social stigma. The second paper takes up the question of corruption tolerance: given that reporting corruption is often socially beneficial but individually costly for citizens, under what conditions will whistleblowers emerge? I show that individuals' motivations to engage in costly monitoring are shaped by the formal institutional environment. In particular, effective enforcement institutions that take citizens' reports seriously can bring about greater grassroots engagement by signaling that reporting is a valuable personal sacrifice, rather than the meaningless protest of a "sucker." In the third paper, I reexamine the literature on the moral virtues of corruption. In particular, scholars have argued that individuals often engage in malfeasance out of feelings of obligation towards their family members, friends, and other "insiders." Further, some cultures are said to emphasize particularistic norms more so than others, which helps to explain why these societies also experience higher levels of corruption. I find evidence that although particularism does tend to erode the salience of honesty norms at the individual level, the strength of in-group ties does not seem to vary across the two cultural groups (Northern and Southern Italians) I examine. Overall, the dissertation demonstrates that social norms play an important role in sustaining corrupt practices by helping to define the social appropriateness of illicit behavior. I conclude with a discussion of policy implications, focusing in particular on the role of anti-corruption policies in norms management.