VictorJuiz/thesis huggingface dataset:
Can We Predict the Returns of Crypto-Currencies?
Keywords:  Public Policy Program
Stanford University
Humanities and Sciences
Public Policy Program
Bitcoin
Ethereum
Thesis

In this thesis I investigate the extent to which we can predict the market outcomes of cryptocurrencies. I focus on the two currently most prominent cryptocurrencies: Bitcoin and Ethereum. In the first part of the thesis I investigate whether the price levels of Bitcoin and Ethereum satisfy the weak form of the Efficient Market Hypothesis. I find evidence of weak-form efficiency in the market for cryptocurrencies. In the second part of the thesis I ask whether cryptocurrencies are viewed as an hedging vehicle against the mainstream economy. To answer this question I explore the association between market outcomes for Bitcoin and Ethereum and the Yield Curve. I find limited evidence of an association between the cryptocurrencies market and the Yield Curve. In the third part of the thesis I ask whether the market for cryptocurrencies is driven by noise traders. To answer that I explore the association between market outcomes for cryptocurrencies and qualitative information from Google searches. I find evidence of strong predictability of the price and transaction volume of Bitcoin by indexized Google searches, suggesting that the fashionability and popularity of Bitcoin go hand in hand.
Can You, and Should You, Buy an Innovation Hub?
Keywords: Department of Economics
innovation hub
agglomeration
externalities
firm performance
urban economics
local performance
Microsoft
spillover effect
Thesis

This paper offers some of the first empirical analysis on the impact of innovation hubs on firm and local performance. The Silicon Valley innovation hub is frequently cited as evidence for the success innovation hubs bring through spillover effects which boost local economies. I exploit Microsoft’s 1979 relocation from Albuquerque, New Mexico, to Bellevue, Washington, to analyze the effect of the Seattle innovation hub on its local economy. Using a difference-in-difference approach with quasi-synthetic controls, I find three main results. First, there is no strong evidence for Microsoft triggering the development of a Seattle innovation hub. Second, to the extent to which the Seattle Hub exists, it does not perform significantly better when looking at firm and local performance. Finally, there is evidence that innovation hubs incur higher rent that potentially constrains growth.
Carbon monoxide gas diffusion electrolysis for the production of concentrated C2 products with high single-pass conversion
Keywords: Chemistry.

Anthropogenic climate change will cause irreparable damage to the environment if measures are not taken to abate the emissions of CO2. One way to drive emissions down is to valorize CO2 by using it as a carbon source for the synthesis of chemical feedstocks. The development of new technologies that produce chemicals from CO2 in a cost competitive and efficient way could put market pressure on existing fossil-derived petrochemicals and incentivize the capture of CO2 from concentrated point sources such as power plants. One attractive strategy for CO2 valorization is to use renewable energy to power the aqueous electrochemical reduction of CO2 and H2O to generate valuable C2+ chemical feedstocks such as ethylene, ethanol, propanol, and acetate. Unfortunately, the spontaneous reaction of CO2 and HO-- to form HCO3-- and CO32-- impedes the optimization of these systems. While the operation of CO2 reduction cells with alkaline electrolytes results in low total cell voltages, the super stoichiometric consumption of MOH in these systems represents a significant energy penalty. Furthermore, only low single-pass conversions have been achieved for CO2 electrolysis resulting in dilute product streams that are energy intensive to purify. Deconstructing CO2 reduction into two separate electrochemical steps may offer a path to overcome the challenges posed by direct electrochemical CO2 reduction. In this two-step process, CO2 is first converted to CO with a high temperature solid oxide electrolysis cell (SOEC), in which the reaction of CO2 and HO-- is avoided. The CO is subsequently reduced in a separate electrochemical cell to generate C2+ chemical feedstocks. While SOECs have recently been brought to market, relatively little is known about how to design an efficient CO electrolysis device that can achieve high single-pass conversions. For the first time, various cell configurations for CO electrolysis are evaluated and high single-pass conversions exceeding 80% are demonstrated corresponding to gas product streams which are greater than 24 vol% ethylene. Through device engineering liquid product streams that are greater than 1 M in sodium acetate are produced. Finally, an innovative deposition technique is developed to generate thick, highly active catalyst layers for CO reduction cathodes, resulting in improved device performance. The results obtained herein indicate the advantages of CO reduction over direct CO2 reduction. The exploration of various cell configurations informs future efforts to design and build larger scale CO electrolysis devices.
Catalyzing electrochemical oxygen reduction to form hydrogen peroxide : from catalyst development to device integration
Keywords: Chemistry.

Hydrogen peroxide (H2O2) is a highly valuable chemical with wide range of applications in industry such as paper bleaching, textile manufacturing and environmental protection. Currently, the industrial synthesis of H2O2 is through an energy intensive anthraquinone process, which requires large-scale and complex infrastructure. Electrochemical synthesis of H2O2 from oxygen reduction offers an attractive alternative route for onsite applications, while the efficiency of this process greatly depends on identifying cost-effective catalysts with high activity and selectivity. As several classes of catalysts have been reported or proposed by theory to be good candidates of the targeted reaction, here we focus our attention upon a metal-organic framework (MOF) and high-performance carbon catalysts for the perspective of both fundamental understanding and the high cost-efficiency. Catalytic systems whose properties can be systematically tuned via changes in synthesis conditions are highly desirable for applications in catalyst design and optimization, namely, the 2D conductive metal--organic framework (MOF) with M-N4 units (M = Ni, Cu) and a hexaaminobenzene (HAB) linker as a catalyst for the oxygen reduction reaction (ORR). By varying synthetic conditions, we synthesized two Ni-HAB catalysts with different crystallinities, resulting in a catalytic system with variable electrical conductivity, electrochemical activity and stability. We show that crystallinity has a positive impact on conductivity and demonstrate that this improved crystallinity/conductivity improves the ORR performance of our model system.
Celestial seductresses and hungry ghosts : preta narratives in early Indian Buddhism
Keywords: Religious Studies.

In this dissertation I examine tales about the departed (Sanskrit: preta) composed in Sanskrit and Pāli from approximately the third century BCE to the sixth century CE. I argue that the body of the preta was essential to the construction of a Buddhist cosmology rooted in a socio-karmic discourse that is fundamentally physio-moral in nature. Through the body, I trace the transformation of the departed preta to the preta as a ghost constituting a separate realm of rebirth in the Buddhist cosmos. By telling stories about pretas, whose bodies are constituted by their prior actions and simultaneously restrict their ability to act toward soteriological goals, Buddhist authors created and illustrated their understanding of moral law of cause and effect. Additionally, the Buddhist saṅgha's claim to be able to transform abject preta bodies into divine ones allowed monks to elevate themselves as the superior mediators between humans and non-humans. While all men and women in these stories act immorally, their depiction is influenced by a social system that upheld the patriarchal householder structure and by a monastic institution that guarded itself against sensual desires and attachment to the body. For this reason, preta tales produce an ideological discourse of the body.
The cell biology of LRRK2 kinase activation and phosphorylation of Rab GTPases
Keywords: Biochemistry.

LRRK2 kinase mutations cause familial Parkinson's disease and increased phosphorylation of a subset of Rab GTPases. Rab29 recruits LRRK2 to the trans-Golgi and activates it there, yet some of LRRK2's major Rab substrates are not on the Golgi. The second chapter of this thesis describes the cell biology of LRRK2 activation. Unlike other Rab family members, we show that Rab29 binds nucleotide weakly, is poorly prenylated, and is not bound to GDI in the cytosol; nevertheless, Rab29 only activates LRRK2 when it is membrane bound and GTP bound. Mitochondrially anchored, GTP-bound Rab29 is both a LRRK2 substrate and activator, and it drives accumulation of active LRRK2 and phosphorylated Rab10 on mitochondria. Importantly, mitochondrially anchored LRRK2 is much less capable of phosphorylating plasma membrane--anchored Rab10 than soluble LRRK2. These data support a model in which LRRK2 associates with and dissociates from distinct membrane compartments to phosphorylate Rab substrates; if anchored, LRRK2 can modify misdelivered Rab substrates that then become trapped there because GDI cannot retrieve them. Work in the third chapter examines Rab29's possible function and effector proteins. The data demonstrate that there are no significant Golgi structure or retrograde trafficking defects upon Rab29 depletion. Immunoprecipitation followed by mass spectrometry indicates that active Rab29 preferentially binds a calcium channel. Additionally, nucleotide free Rab29 preferentially binds to a GEF complex. These data suggest that Rab29 regulates calcium signaling at the Golgi and may be activated by a GEF complex that also activates Rab7.
Challenges in CT with photon counting detectors
Keywords: Bioengineering.

With many attractive attributes including improved tissue characterization, reduced noise, and lower dose, photon counting detectors (PCDs) with multiple energy bins are being considered for clinical CT systems. A major problem with PCDs is the slow count rate, resulting in count rate loss and pulse pileup. Another challenge to PCDs with multiple energy bins is the large amount of projection data acquired that must be transferred in real time through slip rings to data storage subsystems, causing a bandwidth bottleneck problem. Our goal is to address these challenges with a dynamic bowtie filter, a pulse pileup modeling, and a compression algorithm for PCD projection data. A dynamic bowtie modulates flux distribution as a function of fan and view angles to reduce dose, scatter, and detector dynamic range. One approach, the piecewise-linear attenuator (Hsieh and Pelc, Med Phys 2013), consists of multiple wedges, each of which covers a different fan angle range and is moved in the axial direction to change the thickness seen in an axial slice. Our implementation of the filter with precision components and a control algorithm reduces the detected flux dynamic range to 42 for a chest and 25 for an abdomen, corresponding to a reduction factor of 5 and 11 from the object scans without the bowtie. The thickness profile of the piecewise-linear attenuator is proportional to wedge position and is sensitive to the precision of wedge control. Thus, we propose another dynamic bowtie design called a fluid-filled dynamic bowtie filter (FDBF), a two-dimensional array of small binary elements (filled or empty), that may be more reproducible due to digital control. On average, for simulated scans of chest, abdomen, and shoulder sections of an anthropomorphic phantom, the proposed FDBF reduces the maximum-count-rate required of a PCD to 1.2 Mcps/mm2, which is 55.8 and 3.3 times lower than the max-count-rate of the conventional bowtie and the piecewise-linear bowtie, respectively. For the pulse pileup effect, the performance of several analytical models are dependent on the assumptions used, including the assumed pulse shape which could differ from the actual one. From our sensitivity analysis of a pileup model by Taguchi et al. (Med Phys, 2010), the accuracy of some parameters such as the deadtime are more important than others, and they matter more with increasing count rate. For the bandwidth problem, we explored the use of data compression that could be performed prior to transmission through the slip ring. Utilizing the dependencies in the multi-energy data, our proposed compressor achieves an average compression ratio of 2.25:1 for lossless compression and 4.27:1 for lossy compression.
Characterization of Differences in the Forelimb Motor Pools of the RNU Nude Rat
Keywords:  Department of Biology
RNU nude rat
retrograde tracing
immunodeficient
forelimb neuroanatomy
motor neuron pools
Fluoro-Gold
Thesis

Immunodeficient “nude” rats are widely used for spinal cord injury research despite the lack of neuroanatomy characterization specific to this rat. This research has continued without characterization of the neuroanatomy because, from a neurological perspective, nude rats are assumed to be faithful models for non-immunodeficient rats. This assumption is made despite the neuroendocrine differences associated with nude rats being athymic, as well as other, more subtle differences that have been observed in the spinal column of nude rats. In this study we characterized the motor neuron pools which innervate the forelimb muscles of the RNU-/- nude rat and also investigated the extent to which the motor neuron pools differed in number and localization between RNU-/- nude rats and RNU+/- non-nude rats as a control. Using the tracer Fluoro-Gold, we performed retrograde tracing of four different forelimb muscles as well as behavioral testing. We ultimately found a 16-fold reduction in the number of labeled motor neurons innervating the forelimb muscles of nude rats in comparison to non-nude rats. We were also able to localize the forelimb motor neuron pools of the RNU rats for the first time, which appeared to span a longer range of vertebrae than has previously been described in other rats. These findings of neuroanatomical differences in the RNU-/- rat serve to demonstrate confounding variables that are not currently being accounted for in spinal cord injury research. Further, our characterization data supports the notion that the nude rat may have important differences to the non-nude rat.
Characterization of Human Invariant Natural Killer T Cell Subset Heterogeneity via High-Dimensional Analysis
Keywords:  Department of Biology
Biology
GVHD
aGVHD
iNKT
Transplantation
Tolerance
Autoimmunity
Transplant Tolerance
Thesis

Human invariant natural killer T cells (iNKTs) are a set of innate-like lymphocytes that share the properties of both natural killer cells (NKs) and T cells. iNKTs exhibit a variety of different phenotypes and functions, with implications in autoimmunity, transplant tolerance, and the regulation of infections. However, in humans they are rare and not yet characterized adequately. In this thesis, a high-dimensional, data-driven approach was used to provide better clarity between the different iNKT phenotypes and their biomarkers, as well as their major functional population subsets. The data hint at a new combination of conventional and novel markers for these populations. Most saliently, a highly cytotoxic iNKT subset and a pro-inflammatory subset are both identifiable. The identification of these subsets is clinically relevant, as they may correlate with acute graft-versus-host disease (aGVHD) after allogeneic hematopoietic cell transplantation (HCT).
Characterization of hydrogel contact lens materials and their interaction with tear film proteins
Keywords: Chemical Engineering.

The human tear film is a thin fluid film that coats the corneal epithelium of the eye, protecting it bacteria and debris. Maintaining a stable tear film is important for ocular health and comfort; issues associated with tear film stability and ocular surface health can result in feelings of dry eye and discomfort. These symptoms are especially common in patients using contact lenses and are the primary cause for contact lens dropout. To better understand some of the factors that may govern contact lens discomfort, this dissertation focuses on fundamental properties of contact lens hydrogel materials, the human tear film, and the interface between the tear film and contact lenses. Firstly, we wanted to better understand the complex chemistries present in various contact lens materials and we developed methods using solid-state NMR to do so. Using this method, we were able to estimate the molecular contributions of major lens components and were also able to estimate the uptake of a tear film protein, lysozyme, within contact lenses in an in vitro setting. The technique ultimately allowed us to demonstrate that a benzotriazole-based UV-blocker found within commercial contact lens materials also functions as an antioxidant and protects protein deposits from oxidation. The second half of this dissertation focuses on tear film stability, which we first studied in the presence of contact lenses. We investigated the effect of protein deposition on contact lenses on the stability of the tear film to understand if discomfort associated with protein deposition could be attributed to a physical instability in the tear film. Protein deposition was found to increase the surface wettability of contact lenses; however, contact lens surface wettability in saline was uncorrelated with fluid film stability in an artificial tear solution due to the interfacial fluid properties of the artificial tear film. Instead, evaporation from contact lenses was a better indication of the tear film stability in this in vitro setting. Finally, because some contact lens discomfort arises from inherent deficiencies in a patient's tear film, we also focused our efforts on the contribution of the mucin layer to tear film stability in the absence of contact lens materials. We found that mucins help contribute to tear film stability by altering the van der Waals forces within the film, giving rise to a disjoining pressure; additionally, in the presence of evaporation, there are thermal and solute gradients that cause surface-tension driven flow (Marangoni flow) which also stabilizes the film. Together, this dissertation sheds light on some of the potential contact lens and tear film factors that have been hypothesized to affect contact lens comfort in patients and introduces new methods to study additional physicochemical factors related to the tear film and contact lens materials.
Characterizing and Improving Transient Over-Expression Screens in Maize
Keywords:  Department of Biology
Biology
Maize
Transcription Factors
Screen
Over-expression
T7
Thesis

Transcription factors (TFs) are key regulators of cell state changes. Understanding the role of different TFs in regulating cell state transitions can deepen knowledge of an organism’s developmental programs. In plants, numerous TFs have been found to play important roles in differentiation pathways (Schoof et al., 2000). Because plants have so many TFs (constituting approximately 10% of all genes) (Gonzalez, 2016), screening the function of each TF is difficult. In this thesis, my objective was to develop a screen that determines Zea mays TF function through ectopic expression of a TF gene in maize protoplasts followed by detecting transcriptome changes using an RNA-Seq readout. I used two genes with known roles in the maize anthocyanin pathway, R and C1, to validate the effectiveness of the screen. Additionally, I miniaturized the screen to permit scalability in future studies. Lastly, I tested the feasibility of a T7 expression system to induce high expression levels sufficient for enabling a pooled screen approach.
Characterizing the Pro-Degenerative Functions of Rufy3 and p53 in Axon Degeneration
Keywords:  Department of Biology
Biology
neurobiology
axon degeneration
trophic deprivation
Rufy3
p53
Thesis

A key process shaping neurodevelopment is competition between individual axons for limited neurotrophic support. Local deprivation of trophic factors triggers caspase-dependent axon degeneration, which is carried out through apoptotic machinery present in axons. Although some effectors of degeneration have been defined, the complete pathways and molecular mechanisms remain undiscovered. In this project, I looked at two aspects of axon degeneration. First, in looking for potential effectors, I performed a CRISPR knockout screen to identify key effectors necessary for degeneration. I successfully identified Rufy3 as a neuron-specific effector in this caspase-based degeneration pathway, confirming an observation made in a preliminary shRNA screen. Next, I examined the upstream activating role of p53. Seeking to understand the temporal and spatial details of its involvement, I tested the effects of various p53 overexpression constructs on caspase activity. I demonstrated that cytoplasmic function of p53 is important for caspase activity, possibly through an acute mechanism. Taken together, these results provide new insights into the molecular mechanisms of programmed degeneration, a process which may contribute to the underlying pathology of neurodevelopmental disorders and neurodegenerative disease.
Characterizing the role of NGLY1 and proteasomal inhibition in Nrf3 regulation
Keywords:  Department of Biology
Nrf3
NGLY1
glycosylation
carfilzomib
cellular stress
carcinogenesis
cellular biology
Thesis

Nuclear Factor Erythroid 2 Like (Nrf) transcription factors are a family of cap n’collar factors that regulate several metabolic pathways. Recent research has illustrated Nrf1, a member of this family, as the proteasomal subunit regulator and a potential target for cancer therapeutics. Nrf1 is an endoplasmic reticulum (ER)-bound protein in its glycosylated state, when it has glycosylated asparagine residues, a post-translational modification regulatory mechanism. In its deglycosylated state, however, it localizes to the cytosol or nucleus in the case of proteasomal inhibition. N-glycanase 1 (NGLY1) is the human cytosolic enzyme responsible for cleaving N-glycans (i.e. deglycosylation).
Nrf3 is another member of this family with significant homology to Nrf1, and presumably, comparable glycosylation regulation patterns. While Nrf3’s normal cellular function and target genes are unclear, research implicates Nrf3 in carcinogenesis, but Nrf3’s mechanistic roles in these pathways are unknown. Here we investigate NGLY1’s impact on Nrf3’s cellular processing, localization, and target gene expression. Previous research shows Nrf3 protein of differential molecular weights and subcellular localization dependent upon PNGase F (a bacterial glycan-cleaving amidase) activity, suggesting glycosylated and deglycosylated forms; however, NGLY1’s role as the cellular deglycosylating enzyme in Nrf3 processing and localization has not been established. By inhibiting NGLY1 in breast cancer cell lines (MDA-MB 231) and treating them with a proteasomal inhibitor, carfilzomib, we investigated changes in Nrf3’s subcellular localization in the presence or absence of deglycosylating activity and cellular stress. Additionally, by exposing Ngly1-/- human embryonic kidney (HEK) cells to carfilzomib, we examined Nrf3 processing under the similar conditions.
We find that Nrf3 cleavage from the ER and nuclear localization occur in the presence and absence of NGLY1 activity, but that NGLY1’s deglycosylating activity could be necessary for Nrf3’s activation. and eventual target gene regulation. This insight into Nrf3’s regulation presents Nrf3 activity as an additional substrate of NGLY1, providing potential therapeutic target considerations in relevant cancers.