VictorJuiz/thesis huggingface dataset:
Governing trade beyond tariffs [electronic resource] : the politics of multinational production and its implications for international cooperation
Keywords: Political Science.

While tariffs have been effectively eliminated over the last 50 years, a number of regulatory barriers to commerce persist. This thesis explains this persistence as a consequence of the interests of firms and governments and the limits of existing international institutions. This thesis develops three general findings. First, unlike with tariffs, the elimination of regulatory barriers to trade is not in the competitive interests of the most internationalized firms. Second, governments have an interest in using regulations to attract investment and retain the profits of that investment. Third, the existing institutions that govern trade, while able to resolve tariffs, are ill suited to address the challenges of regulatory protection. These three findings, illustrated with formal and empirical analysis, explain why cooperation in the area of regulatory protection remains difficult.
Green fluorescent protein and its 10th [beta]-strand [electronic resource] : controlling protein-peptide interactions with light
Keywords: Chemistry.

Truncated green fluorescent protein (GFP) that is refolded after removing the 10th [beta]-strand (s10) can readily bind to a synthetic strand to recover the absorbance and the fluorescence of the whole protein. This allows rigorous experimental determination of thermodynamic and kinetic parameters of the split system including the equilibrium and the association/dissociation rate constants, which enables residue-specific analysis of protein-peptide interactions. The equilibrium constant obtained from the ratio of the two rate constants agrees with that directly estimated from the binding isotherm, which supports the one-to-one binding model. In measuring the dissociation rate of s10, it was discovered that the strand can photodissociate, where the dissociation rate is greatly increased by light irradiation. We found that in the overall photodissociation process, a thermal step follows light-activation of the molecule, and the thermal activation barrier was determined through an Arrhenius plot of the rate constants acquired at a saturating light intensity. The thermal step could be selectively affected by mutating residue 209 on s10 and by changing the solvent viscosity, which suggests that the thermal step is the actual dissociation of s10. In the process, we found that the quantum yield of photodissociation can be enhanced by increasing the temperature or lowering the viscosity of the solvent, or by introducing mutations such as K209Q or Y203T. For the light-activation step, cis-trans isomerization of the chromophore could be suggested as the underlying mechanism referring to the previous work on truncated GFP with strand 11 removed (Kent and Boxer, 2011). Photodissociation links photoexcitation of the protein to its conformational change, which opens the possibility of using GFP in caging. Finally, GFP variants carrying one extra s10 were created and characterized, and their possible applications were explored. These proteins can fold with either one or the other s10, and the ratio of the two folded forms, unambiguously distinguished by their resulting colors, can be systematically modulated by mutating the residues on s10 or by changing the lengths of the two inserted linker sequences that connect each s10 to the rest of the protein. Exploiting studies on photodissociation, ratiometric protease sensors were designed from the construct by engineering a specific protease cleavage site into one of the inserted loops, where the bound s10 is replaced by the other strand upon protease cleavage and irradiation with light to switch its color. Since the conversion involves a large spectral shift, these genetically encoded sensors display very high ratiometric dynamic range. Further engineering of this class of proteins guided by mechanistic understanding of the light-driven process will enable interesting and useful applications of the protein.
Gurus on loan [electronic resource] : an ethnographic study of an intercultural knowledge-transfer program in a multinational company
Keywords: Management Science and Engineering.

Transferring knowledge and practices across cultural boundaries has become increasingly important for today's multinational companies (MNCs). Yet, knowledge and practice transfer is often difficult to achieve, and management scholars insufficiently understand how individuals accomplish this transfer in their everyday work. Using ethnographic methods, I closely studied how some knowledge transfer rotations in an MNC unfolded over time. My analysis unearthed multiple types of challenges in transferring knowledge and practices—challenges that existing theories of knowledge and practice transfer cannot adequately explain. To account for my empirical findings, I propose a practice-based framework of knowledge transfer that integrates the perspectives of both the knowledge sender and the knowledge receiver. The framework identifies two necessary components of knowledge transfer: knowledge reenactment by the sender and knowledge reconstruction by the receiver. I highlight three practices that are important yet challenging for the parties involved: Entry point identification for the sender to reenact knowledge, active observation and meaning reconstruction for the receiver to accurately process the knowledge that is enacted by the sender. I conclude by discussing (a) some theoretical implications of the study for the literature on knowledge and practice transfer and the literature on international assignment, and (b) some practical implications for managing knowledge transfer within MNCs.
Gyro-based multi-image deconvolution for removing handshake blur [electronic resource]
Keywords: Electrical Engineering.

In low-light situations, long exposures are inevitable to improve the image quality, but, in turn, handshake blur becomes significant. Although image deblurring techniques have been intensively studied, most methods are brittle and computationally expensive, making them hardly usable in practice. This dissertation presents a new gyro-based multi-image deblurring system that handles various challenges in real-world situations. Instead of capturing a single long exposure image, a burst of shorter exposure images is captured along with gyroscope data being recorded at the same time. Then, any camera shake that occurred during the capture is removed to obtain a sharp and noise-free image of the scene. Because both camera motion and the scene are accurately measured with a better capture method, gyro-based multi-image deblurring is more robust than previous approaches while its computational burden is significantly reduced. In addition to the implementation, an important property of multi-image deblurring is presented: Multi-image deconvolution does not benefit from increasing exposure time beyond a certain threshold. The noise reduction granted by increasing exposure time is mostly offset by the noise amplification incurred by the more extreme deblurring. Based on this analysis, different capture strategies are compared in various photographic situations, demonstrating that multi-image deblurring is a robust approach that works in low-light situations when other methods fail.
Happy meals [electronic resource] : animals, nature, and the myth of consent
Keywords: Modern Thought and Literature.

In describing man as an "animal rationale, " Aristotle argued for a "myth of consent, " i.e. that slaves, barbarians, women, and animals have all "agreed" to be owned and controlled by Greek male citizens for their own "protection." Therefore, there are two main themes in Aristotelian thought in the original definition of man, which became inscribed in later thinkers. The first is that the exclusion of the slave, and later of the colonized, as biological inferiors is rendered possible in part because of these pre-existing caesuras in politics, ethics, and philosophy which exclude animals, women, and slaves, based on their shared equation with the human body and supposed lack of reason. And second, this domination is justified via a rhetoric of care and benevolent protection. Based on a critique of this "myth of consent, " in the first half of the dissertation I argue that the practices of "locavorism, " "humane slaughter, " and being a "compassionate carnivore" obscure the reality of the death and suffering that such practices entail. I argue that the effect of the so-called "humane farming" movement is not a critique of anthropocentric privilege, but instead the restatement and re-entrenchment of the most basic claims of the factory farm system. In the second half of the dissertation, I explore the "myth of consent" for marginalized populations which have been oppressed, in part, based on a supposed belief in the need to "protect" them (even when this "protection" involves their death) as well as a belief in their supposed "animalistic" nature. Underlying all of these arguments, I argue that that the question "what is man?" (as opposed to the animal) is not a question philosophy should attempt to answer, but a power dynamic that we should, instead, seek to critique.
Haptic fMRI: Visually Guided Movement & Force Experiments for Understanding Human Neuromuscular Control
Keywords: Program in Biomedical Computation
Stanford Robotics
fMRI
motor neuroscience
haptic fMRI
HFI
functional magnetic resonance imaging
Thesis

Recent advances in combining haptic interfaces with functional magnetic resonance imaging (Haptic fMRI) have enabled motor neuroscientists to design complex experiments that investigate how the human brain coordinates the musculoskeletal system. The human body's numerous and redundant degrees-of-freedom necessitate complex experiments to probe their dynamic range. In this thesis, we present a modular experiment design whose components can be combined to create arbitrarily complex Haptic fMRI experiments that include three-dimensional motor planning, unconstrained reaching, position holding, and visually guided trajectory tracking. Our experiment design achieves consistent response latencies, minimal hand jitter, and stereotypical goal-directed reaches and visually-guided motion trajectories across subjects. Moreover, the intuitive nature of our experiments helped subjects minimize head motion to less than half the spatial resolution of our fMRI scans, and decorrelated hand and head motions. We also establish criteria for including force-based haptic interaction in motor neuroimaging experiments by characterizing how well humans perceive forces. Finally, we determined that Haptic fMRI experiments conducted with the Stanford Haptic fMRI Interface (HFI) avoid task-correlated artifacts---simultaneously imaging a subject's brain with a brain-like phantom revealed no task-correlated noise. The phantom served as an ideal control because it was devoid of physiological activity but could still be affected by experimental artifacts. The experimental framework presented in this thesis sets the stage for future artifact-free motor fMRI experiments with Haptic fMRI that can help us understand how neuromuscular control works in the brain.
Hedgehog signaling in urogenital regeneration and neoplasia [electronic resource]
Keywords: Developmental Biology.

The Hedgehog (Hh) signaling pathway functions in embryonic development to control cell growth, cell fate and pattern many aspects of the vertebrate body plan. The role of the pathway in adult tissue homeostasis, regeneration and cancer, however, is still emerging, especially in the context of epithelial/stromal interactions. Previous work on the adult bladder demonstrated the importance of stromal Hh pathway response in mediating homeostatic response to injury by eliciting production of stromal factors that act on the epithelium; in this dissertation I investigate the role of epithelial/stromal interactions involving the Hh pathway in prostate regeneration and bladder cancer. In the adult prostate, Hh pathway response occurs in a subset of stromal cells. Prostate regeneration involves the formation of new prostate branches, and I showed that stromal cells at the tips of nascent buds lacked Hh pathway response. Decreased pathway activity in stromal cells leads to increased branching, and this correlates with increased secretion of hepatocyte growth factor (Hgf), which acts on the epithelium to induce prostate branching. In regions that are not budding, stromal Hh pathway response down-regulates expression of Hgf. Hence, the spatial organization of stromal Hh pathway response in combination with the negative regulation of secreted hepatocyte growth factor (Hgf) levels by Hh pathway activity, together modulate branching morphogenesis during prostate regeneration. I also examined the role of Hh pathway activity in development of invasive urothelial carcinoma and find, despite its initial presence in the cancer cell of origin, that Sonic hedgehog (Shh) expression is lost during progression. Genetic blockade of stromal response to Shh furthermore dramatically accelerates progression. This cancer-protective effect is associated with Shh-induced stromal expression of BMP signals, which stimulate urothelial differentiation, and progression is reduced by pharmacological activation of BMP pathway activity. Taken together, the results of this dissertation highlight the importance, in regeneration and cancer, of epithelial/stromal interactions in which the Hh pathway is a key mediator. In both models examined, Hh ligand produced by the epithelium stiumates pathway response in the stroma, which regulates the secretion of factors that act on the epithelium. In a broader context, this work provides a conceptual framework for understanding epithelial/stromal interactions involving Hh signaling in other organ systems, a more detailed understanding of which will enable better therapeutic strategies for the treatment of disease.
The hermeneutics of conversion [electronic resource] : fiction and apologetics in François Mauriac and Jean-Paul Sartre
Keywords: French and Italian.

This dissertation analyzes key texts from the 1930s in light of recent scholarly work on secularization. I maintain that conversion novels by Jean-Paul Sartre and François Mauriac function not only as sites for interrogating the credibility of religious forms in the modern world, but also as apologetic tools that train readers in hermeneutic strategies, preparing them for specific modes of engagement in society. For both authors, "the secular" comes to be imagined as a practice of reading guided by a hermeneutic of suspicion. Likewise, a hermeneutic of faith represents a sacred mode of reading. By giving readers hermeneutic training, these texts give credence to Pascal's claim that sustained practices can prepare an individual for conversion, or, as the case of Sartre demonstrates, to prepare an individual to resist conversion.
Heroes on the make [electronic resource] : in the name of Martín-Santos' silence, destruction, and beyond
Keywords: Iberian and Latin American Cultures.

My thesis proposes a new reading of the fictional work of the 20th century Spanish psychiatrist and writer Luis Martín-Santos (Larache, Marruecos, 1924--Vitoria, España, 1964) in which the political drive⎯prevalent in current criticism⎯is not the main guideline to its interpretation. Instead, I propose a reading based on the impact of Martín-Santos' psychiatric essays on his work in fiction⎯mainly in his novel Tiempo de silencio (1962) and in his posthumous fragment Tiempo de destrucción (1975). I analyze the influence of Sartre, Heidegger and Freud in Martín-Santos' non-fictional writings to further apply the latter to his fictional ones. I proceed then to focus on the effects that hegemonic masculinity, in its Contemporary Western patriarchic form, has on the novels' characters as an illustration of Martín-Santos' concept of literature as "desacralizadora" and "sacro-genética." This reading draws on crucial aspects of Luis Martín-Santos' writings in which he was contesting not just the Franco regime but, moreover, it reflects on the patriarchal system and functions of masculinity as one of the most important resonances of his works in the 21st century. I defend a reading of Martín-Santos' creative works as an attempt to destroy the prevalent masculine myths of Western patriarchy, and as a proposal to create the new ones for the future, rendering the spectrum of Martín-Santos' writings relevance far greater than that of a critical political portrait of the Spain of the 1950's.
High-fidelity simulations and modeling of compressible reacting flows [electronic resource]
Keywords: Mechanical Engineering.

Scramjets are air-breathing propulsion devices and have long been recognized as suitable for hypersonic propulsion. Because of the high speed in scramjet combustors, the flow has a very short residence time before leaving the engine, during which air and fuel must mix on a molecular level and chemical reactions have to be completed. Although some ground and flight experiments have successfully demonstrated the feasibility of supersonic combustion, experimental testing requires a large investment and presents numerous difficulties. Computational tools are thus a key element toward the development of an efficient, high-performance scramjet engine, and because mixing and heat release are at the heart of a scramjet operation, the development and use of accurate combustion models for supersonic combustion are critical. The open questions in supersonic combustion span the spectrum from scientific pursuit, e.g., shock/flame interactions, to engineering applications like prediction of unstart phenomena in scramjets. In this study, direct numerical simulations (DNS) of a compressible reacting mixing layer with finite rate chemistry are performed. The DNS databases are used to explore the physics of supersonic combustion. An efficient combustion model based on the flamelet/progress variable is then introduced. In this approach, only two or three additional scalar transport equations need to be solved, independently of the complexity of the reaction mechanism. The proposed combustion model is validated using DNS databases. Finally, the compressible flamelet/progress variable model is applied to the case of an under-expanded hydrogen jet in a supersonic cross-flow and HIFiRE scramjet.
High-resolution small animal positron emission tomography system based on 3-D position-sensitive cadmium zinc telluride photon detectors [electronic resource]
Keywords: Electrical Engineering.

A description of the development of the world's first 1 mm resolution, adjustable field of view small animal positron emission tomography (PET) system is presented. The system uses cadmium zinc telluride (CZT) 3-D position sensitive photon detectors comprising CZT crystals measuring 40 mm x 40 mm x 5 mm, and metalized with a cross-strip electrode pattern. High photon sensitivity is achieved by adopting a box geometry for the field of view (FOV) (maximum extent of 100 mm x 100 mm x 80 mm) and an "edge-on" orientation of photon detectors, so that annihilation photons traverse a minimum of 40 mm through CZT. Based on both simulation and experimental investigations, a CZT photon detector was developed capable of resolving the 3-D position of individual photon interactions, making possible a range of new imaging algorithms for random coincidence rejection, line of response (LOR) placement, etc. Comprehensive characterization studies of single-crystal CZT photon detector demonstrated an (x, y, z) spatial resolution of 1 mm x 5 mm x ~0.5 mm and energy resolution of ~3% FWHM at 511 keV . This work further produced a full data acquisition (DAQ) chain for the PET system, comprising front-end boards based the RENA-3 ASIC capable of 50 Mbps data transmission, 48:1 fan-in boards connecting the front-end to the backplane, and a daisy chain backplane bus capable of 800 Mbps data transmission, connected to a DAQ computer via a 1 Gbps Ethernet connection. A software tool suite was developed to incorporate novel time and energy measurement calibration techniques and a new time coincident event identification algorithm for semiconductor photon detectors. The system's mechanical gantries and housings were fabricated, along with detector assembling and testing equipment. A prototype of the small animal PET system built to facilitate integration testing and troubleshooting yielded preliminary system-wide FWHM energy and coincidence time resolutions of 8.02 +/- 0.96% and 3.12 +/- 0.15 ns, respectively. Further system-level characterization experiments are on-going to validate these initial results, and subsequently, to assess the system's PSF, and reconstructed image resolution and contrast.
High-speed multimodal microscopy for studying structural dynamics of biomolecular machines [electronic resource]
Keywords: Applied Physics.

Single molecule tracking and manipulation is now an established approach for interrogating the dynamics of biomolecular systems, both in vivo and in vitro. By reporting nanoscale displacements of functioning complexes, constraints can be placed on structural rearrangements (such as in motor activity) as well as transition kinetics. This information is obtained directly from individual molecules, permitting branched pathways and statistical distributions to be observed rather than bulk means. However, single molecule experiments can exhibit low dimensionality and poor signal-to-noise. In particular, the spatiotemporal resolution of DNA twist measurements has been limited by the use of angular probes with high rotational drag, which prevents detection of short-lived intermediates or small angular steps. We introduce gold rotor bead tracking (AuRBT), which yields > 100× improvement in time resolution over previous techniques. AuRBT employs gold nanoparticles as bright low-drag rotational and extensional probes, which are monitored by instrumentation that combines magnetic tweezers with objective-side evanescent darkfield microscopy. Our analysis of high-speed structural dynamics of the enzyme DNA gyrase using AuRBT revealed an unanticipated transient intermediate. AuRBT also enables direct measurements of DNA torque with > 50× shorter integration times than previous techniques; we demonstrated high-resolution torque spectroscopy by mapping the conformational landscape of a Z-forming DNA sequence. Additionally, we have augmented our system with synchronous single fluorophore imaging, in order to detect the binding of DNA, proteins, or ligands to mechanochemical substates identified by highspeed tracking. We have validated the use of FRET in combination with rotor bead tracking as a tool to probe intramolecular dynamics simultaneously with mechanical degrees of freedom, generating multidimensional data that reports on the highspeed structural dynamics of functioning molecular machines.