VictorJuiz/thesis huggingface dataset:
The Regulators of Citizenship: The Labor Law Establishment and Domestic Workers in Brazil, 1922-1972
Keywords: Brazil
Household employees
Household employees > Labor unions
Household employees > Legal status, laws, etc.
Household employees > Religious life
Household employees > Social conditions
Women household employees
History
Labor laws and legislation
Labor laws and legislation, International
Bureaucracy > Decision making
Vargas, Getúlio, 1883-1954
Brazil. Ministério do Trabalho e Previdência Social
Brazil. Ministério do Trabalho, Indústria e Comércio
Instituto Nacional de Previdência Social
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Thesis

This thesis presents a history of domestic worker rights in Brazil between 1922 and 1972. Between 1922 and 1937, activists almost secured protections for household workers along with other urban laborers. Between 1937 and 1960, the Labor Ministry bureaucracy made a technocratic decision to exclude them from labor laws and Social Security. Between 1960 and 1972, a combination of activism and technocratic goodwill secures household workers with their first set of enforceable rights. Beyond household work, the thesis describes the inner workings of the Brazilian Labor Ministry bureaucracy during the mid-twentieth century.
The role of DNA endoreduplication in ABA's regulation of root growth in Arabidopsis thaliana
Keywords:  Department of Biology
Water stress
Biology
Abscisic acid
Roots (Botany) > Growth
Arabidopsis thaliana
Endoreduplication
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Thesis

Climate change is expected to bring shifts in global precipitation, and in areas where water availability is limiting, adaptations to water-deficit stress are essential. Roots play an essential role in acquiring nutrients and water necessary for plant plant growth, and recent research has shown that root growth patterns during periods of water stress can be highly variable within taxonomic groups. Abscisic acid (ABA) is a stress-response hormone that has been demonstrated to be an important regulator of root growth, and there is evidence that increasing ploidy in root cells, a process called endoreduplication, may increase root extension by enlarging root cell size. However, the pathway through which ABA regulates root endoreduplication processes is still unclear. The purpose of this study is to investigate the divergence of the endoreduplication pathway in regulating root growth response to stress in the Brassicaceae family. For this project, DAPI staining and confocal fluorescence microscopy protocols were developed for quantification of nuclear area. Transgenic mutants were then used to identify the ABA-driven response of genes regulating endoreduplication in the model species Arabidopsis thaliana. Identifying the role of ABA in root developmental processes provides a better understanding of changes in root growth in response to environmental factors such as water stress. Furthermore, this research has the potential to inform new methods of plant genetic modification that support the goal of establishing new plant varieties better suited to the changing conditions of the anthropocene
The Role of the Circadian Clock in Myelin-Forming Cells in Health and Disease
Keywords:  Department of Biology
Kim, Samuel
circadian rhythm
oligodendrocyte
myelin
neurological disease
Stanford Department of Biology
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Thesis

Myelin is integral to neural circuit function. Nearly half of the human brain is composed of white matter tracts, all of which are created by oligodendrocytes. Oligodendrocyte precursor cells (OPCs), the precursor cell population that gives rise to myelinating oligodendrocytes, are critical in maintaining oligodendrocyte homeostasis. OPCs are the most robustly cycling cell in the brain, yet the mechanisms maintaining this stability remain incompletely understood. One mechanism closely interconnected with cell cycle regulation is the circadian clock. At the cellular level, circadian rhythms are generated ubiquitously throughout the brain and body by a transcriptional/translational feedback loop driven by the transcription factor BMAL1. This thesis elevates the current biological understanding of myelin processes through novel convergence with circadian biology. Specifically, the role of circadian regulation in developmental myelination is investigated by genetic knockout of Bmal1 specifically in OPCs during developmental myelination. OPC and mature oligodendrocyte density is reduced by ~40% in OPC-specific Bmal1 knockout (Bmal1 KO) mice compared to circadian intact OPCs in wild type (Bmal1 WT) mice at postnatal day 21 (P21). Bmal1 KO mice exhibit an ~7% decrease in myelin sheath thickness and ~40% decrease in myelin basic protein (MBP) content, a protein integral to the formation of compact myelin. These deficits in OPC lineage dynamics and myelin are associated with a significant dysregulation of motor and cognitive function exemplified by decrements in limb swing speed and stride length at P35 and deficits in cognition at P63 as assessed using a modified novel object recognition test. Taken together, these data suggest a significant role for the circadian clock protein BMAL1 in the regulation of myelination and a novel avenue by which to evaluate neurological disease..
The Role of Transcription Factor FOXP2 in Tadpole Social Communication
Keywords:  Department of Biology
biology
neuroscience
FOXP2
begging
communication
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Thesis

Communication of hunger during infancy is our first social interaction, laying the foundation for a healthy life by acquiring nutrition and establishing strong social bonds with caregivers. However, the neural basis of neonate social communication is not well understood. Forkhead Box P2 (FOXP2) protein has been implicated in several human communication disorders, including deficits in language through abnormal development of motor neural circuits. This protein has also been linked to communication in songbirds, honeybees, and rodents. I studied the neural basis of neonate communication of nutritional need in Mimic poison frog (Ranitomeya imitator) tadpoles. In this species, mothers feed tadpoles unfertilized eggs after the tadpole performs a begging display characterized by vigorously dancing back and forth. Preliminary data suggested that FOXP2-positive neurons are active during these tadpole begging displays. In this study, tadpoles were placed individually in an arena for 30 minutes with either an adult female frog or a novel object as a non-social control. After quantifying the begging behavior displayed by the tadpoles, the tadpole heads were isolated and immunohistochemistry was used to visualize a marker of neural activation (pS6) and FOXP2 in the brain. FOXP2 was widely distributed, with FOXP2-positive cells present in the striatum, hypothalamus, and spinal cord, among other brain regions and the eye. In particular, FOXP2 colocalized with a marker of neural activation predominantly in the cerebellum, indicating that cerebellar FOXP2 may play a role in coordinating begging behavior. Overall, this work suggests a potential conserved role for FOXP2 in social communication and provides important insights into how infants convey hunger.
The role of translation equivalents in bilingual word learning
Keywords: Bilingualism in children
Learning
Language acquisition
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Thesis

Bilingual environments present an interesting context for word learning, notably due to the existence of translation equivalents (TEs)—words in different languages that share very similar meanings. Understanding how these TEs are learnt may give us insight into mechanisms underlying word learning in young children. In Study 1, we investigated this by conducting a systematic literature review and meta-analysis of TEs in children's vocabularies, finding significant variability with age as a moderator. In Study 2, we then conducted an analysis of Communicative Development Inventory (CDI) data from bilingual children, finding that older children and children with more balanced language exposure had a higher proportion of TE pairs in their vocabularies. However, both of these approaches were susceptible to the baseline problem—the potential confound of overall vocabulary growth (which would lead to a greater set of opportunities for learning TEs). Hence, in Study 3, we moved to an item-level analysis, finding that knowing a word's TE increased the likelihood of knowing that word itself for younger children, and for TEs that are more similar phonologically. Thus, TEs provide an alternative source of information for younger children, thereby allowing bilingual children to bootstrap their word learning in one language using their knowledge of the other language.
The Woman Writer’s Baedeker: Mina Loy as Feminist Modernist Guide and Artist-Philosopher
Keywords: Feminism
Modernism (Literature)
Poetry, Modern
Genius in literature
Women in literature
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Thesis

The work I examine closely in this thesis is Lunar Baedecker [sic], a 1923 collection of poems written by British-born modernist poet Mina Loy. Though several of the poems that constitute Lunar Baedecker have been explored extensively as anthology entries and epigraphs, scholars have largely neglected to analyze the 1923 poetry collection as an intentionally curated whole. This gap in Loy scholarship may exist in part because the collection appeared in print only once. Still, Lunar Baedecker is the only compilation of Loy’s poems we know she exercised organizational control over, and therefore it holds rich critical potential. I propose that Lunar Baedecker is a figurative map of Loy’s journey as a female artist, from her early veneration of her male contemporaries to her eventual severance from them, and thereby offers a gynocentric alternative to the historically dominant, androcentric narratives around literary genius. I’ve based my interpretation of Lunar Baedecker on the structure and content of the collection and contextualized my interpretation of her poetry alongside her prose essays on modernism and feminism, including “Feminist Manifesto” (1914) and “The Metaphysical Pattern in Aesthetics” (n.d.).
The world of Ito Junji: Social criticisms and the reflections of horror within Japanese society
Keywords:  Stanford Global Studies
Ito Junji; Japan; Horror; manga; social criticism; children; institutions; agency; East Asia
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Thesis

*CONTENT WARNING* Depictions of death, gore, and suicide
This thesis explores the works of horror manga artist Ito Junji and analyzes the ways in which Ito criticizes certain institutions and individuals within Japanese society. His criticisms bring to light the fact that many social institutions that were meant to benefit individuals have changed in their function and instead work to harm those it was set up to help. It also delves into Ito’s portrayal of children in horror and how they are granted agency in a genre that often treats them as objects.
Theoretical and computational tools for predicting colloidal gelation and arrest phenomena
Keywords: Chemical Engineering.

The purpose of this thesis work is to develop a new set of theoretical and computational tools that will accurately predict lines of gelation in a colloidal phase diagram for suspensions of hard spheres of arbitrary size polydispersity, as a general model for gelation behavior in more complex colloidal materials. Although our algorithmic approach, results, and toolkit is generally valid for a wide range of colloidal systems, framework was constructed, tested, and validated for a specific laboratory material developed by the Helgeson Laboratory at the University of California - Santa Barbara. We demonstrated a powerful coupling between theory, simulation and experiment that can be utilized to construct a computational model that faithfully represents the particle-scale interactions and resulting macroscopic phase behavior of a real laboratory material. This thesis is divided into three parts. First, we present a novel computational technique for extracting the detailed interactive potential between individual colloids from experimental data (Chapter 3). The result of this effort is construction of an analytical potential that accurately responds to temperature to produce gelation that matches the experimental system. Next, in Chapter 4, we use our method to expand the phase diagram, identifying lines of percolation and vitrification for a range of system potentials. Finally, we demonstrate a new algorithm to reverse-engineer a gel into a computational model (Chapter 5). The algorithm uses microscopy data from experiments to construct a detailed map of the gel, with the crucial step of representing interconnected void networks. This model is the first to accurately obtain the interconnected void structure key to modeling porous structure such as in additively manufactured or biological materials. Overall, these results establish a theoretical and computational toolset for predicting colloidal gelation that matches laboratory experiments. We envision use of these tools to exploit repeated quenching and annealing to achieve exotic new microstructures that improve performance of colloidal solids and discover novel materials
A theoretical and experimental investigation of plasma photonic crystals and devices
Keywords: Mechanical Engineering.

This thesis investigates the use of gaseous plasmas in photonic crystal devices through theoretical approaches and laboratory experiments. A theoretical and analytical framework for one- and two-dimensional plasma photonic crystals is presented in detail, as well as the design and characterization of various experimental photonic devices. The first part of this thesis is focused on understanding the theoretical behavior of plasma photonic crystals, with a characterization of one dimensional and two-dimensional plasma photonic crystals through theoretical approaches. The second half of this thesis focuses on experimentally exploring plasma photonic crystal devices, including the design and construction of a photonic crystal with embedded plasma elements, a full 2D plasma photonic crystal, a full 3D plasma photonic crystal, a hybrid 3D plasma photonic crystal as a platform for optical computing, and microstrip photonic crystal devices with plasma elements. Applications of these devices to microwave circuits, tunable filters, optical computing systems, and artificial neural networks are discussed
Theory and algorithms for efficient deployment of machine learning systems
Keywords: Electrical Engineering.

In this work, we explore theory and algorithms that improve the efficiency of various aspects of machine learning systems. First, we investigate algorithmic principles that enable efficient machine unlearning in machine learning. We propose two unsupervised learning algorithms which achieve over 100 times improvement in online data deletion, while producing clusters of comparable statistical quality to a canonical k-means++ baseline. Second, we explore mixed dimension embeddings, an embedding layer architecture in which a particular embedding vector's dimension scales with its query frequency. Through theoretical analysis and systematic experiments, we demonstrate that using mixed dimensions can drastically reduce the memory usage, while maintaining and even improving predictive performance. Mixed dimension layers improve accuracy by 0.1% using half as many parameters or maintain it using 16 times fewer parameters for click-through rate prediction on the Criteo Kaggle dataset. They also train over 2 times faster on a GPU. Finally, we propose a novel approach, MLDemon, for ML Deployment monitoring. MLDemon integrates both unlabeled data and a small amount of on-demand labels to produce a real-time estimate of a deployed model's current accuracy on a given data stream. Subject to budget constraints, MLDemon decides when to acquire additional, potentially costly, expert supervised labels to verify the model. MLDemon compares favorably to prior methods on benchmarks. We also provide theoretical analysis to show that MLDemon is minimax rate optimal for a broad class of distribution drifts
Thermo-mechanical design and reliability of high-performance ultra-thin vapor chambers
Keywords: Mechanical Engineering.

Silicon-based vapor chambers are an appealing choice for electronics cooling application due to their low thermal resistance and ease of system-level integration. However, challenges in high heat flux applications necessitates development of high-performance evaporator wicks for these two-phase cooling solutions. Here, we design, fabricate, and characterize a novel hybrid microporous evaporator wick capable of removing > 150 W from 5×5 mm2 hotspot (> 600 Wcm-2 heat flux with thermal resistance of 0.02 oCcm2W-1). We use copper wire meshes (CWMs) to provide liquid feeding and copper inverse opal (CIOs) for boiling. Surface oxidation of the copper is a critical degradation mechanism that must be addressed to preserve the integrity and hydrophilicity of the wick. We systematically investigate the contact angle change of micro porous copper. To avoid hydrophobicity, we propose to pre-oxidize the copper evaporator wick to form a hydrophilic cupric oxide CuO. Furthermore, we develop a recipe for creation of a reliable superhydrophilic layer for micro porous wick application. We investigate effect of various maintenance protocols to ensure superhydrophilicity of the wick for long term functionality. Thermo-fluidic performance of ultra-thin vapor chambers has been studied extensively in the past two decades, however; the thermo-mechanical design and reliability of these devices has not received much attention. The mechanical design and reliability of the vapor chamber is crucial for avoiding the device breakdown or leakage due to the high internal pressure. We develop a parametric model for thermo-mechanical design and structural analysis of an ultra-thin (1 mm thickness) miniature (15×15 mm2 area) silicon vapor chamber. We study the effects of various design parameters such as cavity area, cavity thickness, and fillet radius. We introduce the circular cavity design for the vapor chamber application. To increase the mechanical reliability, we propose the implementation and study the design parameters of various mechanical support structures such as ribs, crossbars, and micro-post arrays. The critical point of the mechanical design is the evaporator-condenser bonding area. Gold-tin and gold-silicon eutectic bonding are proposed as the bonding materials and methods. The samples and the tensile test setup are designed, fabricated, and tested specifically for the vapor chamber application. Findings of this study are largely beneficial in development of silicon-based heat spreaders, high-performance thermal rectifiers, next-generation heat routing technologies and heterogeneous two-phase cooling devices
A threatening opportunity : conversations about race-related experiences between Black and White friends
Keywords: Psychology.

Similarities are foundational to building and maintaining friendships, but for cross-race friends, differences in experiences related to race are also inevitable. I theorize that conversations about race-related experiences are a threatening opportunity. In Part I, Black and White friends expected that these conversations can enhance closeness and intergroup learning, but these benefits can be accompanied by identity threat. In Chapter 2, Black and White adults anticipated both benefits and risks of such conversations, though more benefits than risks. In Chapter 3, Black participants reported less willingness to disclose race-related experiences to extant White friends than Black friends and anticipated feeling less comfortable doing so, controlling for closeness. However, they also desired to be understood by Black and White friends equally. In Chapter 4, White participants also felt less comfortable when an imagined Black friend disclosed race-related versus nonrace-related experiences to them. However, they expected to feel closer to their friend after the race-related disclosure. Part II examines real-time video conversations between existing Black and White friends and reframes conversations about race to address friends' identity-based concerns. Findings revealed that Black and White friends are relatively well-positioned to discuss race-related experiences, and the framing had long-term benefits for Black friends' relationship quality, authenticity, and comfort talking about race. Taken together, this dissertation highlights the benefits as well as the risks of conversations about race for cross-race friends and begins to uncover strategies to help friends engage in these conversations productively
Tissue engineered 3D in vitro bone cancer models for elucidating drivers of cancer progression and drug discovery
Keywords: Bioengineering.

Malignant bone tumors are aggressive neoplasms which can arise from bone tissue or as a result of metastasis. The most prevalent types of cancer, such as breast cancer and prostate cancer, preferentially metastasize to bone, yet the role of the bone niche in promoting cancer progression is poorly understood. Tissue engineering tools have the potential to bridge this knowledge gap by providing 3D in vitro platforms that can be specifically designed to mimic key properties of the bone niche. However, most 3D models to date have been designed to mimic soft tissue tumors, which lack the unique matrix and cellular compositions of the bone niche. Here, we present our work on engineering 3D models of osteosarcoma (OS), an aggressive pediatric bone cancer for which treatments have seen little progress in over 30 years. Using microribbon (µRB) scaffolds with bone-mimicking compositions, we evaluated the role of 3D culture and hydroxyapatite in OS signaling and drug response. Our findings reveal hydroxyapatite in 3D was critical to support retention of OS signaling and drug resistance similar to patient tissues and mouse orthotopic tumors. Integrating 3D PDX OS models with RNA sequencing, we identified a 3D-specific druggable target for OS which predicted in vivo drug response. Together, our results demonstrate the potential of 3D µRB models to serve as novel experimental tools to enable discovery of new therapies for OS which would otherwise be missed in 2D screens. Bone is the most frequent site of metastasis in breast and prostate cancer, yet why cancer cells preferentially metastasize to the bones remains unknown. Furthermore, there are currently no effective treatments for bone metastases, highlighting a critical need to elucidate the mechanisms underlying bone metastasis development and establish tools to facilitate the discovery of new therapies. To address this unmet need, we developed 3D in vitro models of breast cancer and prostate cancer metastasis to bone using spatially patterned biomaterials that mimic the in vivo cancer cell interface with bone tissues. Our data demonstrate that spatially patterned, 3D models recapitulate the preferential migration of cancer cells into bone, cancer aggressiveness, and drug response consistent with in vivo models. Importantly, we show that such 3D models can recapitulate cancer-induced dysregulation of bone remodeling, a key pathological outcome in patients which leads to significant morbidity and mortality. Lastly, we demonstrate the potential of integrating spatially patterned 3D models with single-cell RNA sequencing to identify key signaling drivers of cancer metastasis to bone. Taken together, our findings establish spatially patterned 3D in vitro bone metastasis models as a promising platform to elucidate bone metastasis biology and expedite drug discovery