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Assessing Parenting Styles through Online Forums: A Discourse Analysis Approach using the Meaning of the Child Methodology.
No full textThis study investigated whether parenting styles can be reliably analyzed from written parenting discourse (such as that posted on online forums) using the Meaning of the Child (MotC) methodology. The research focused on two primary hypotheses: (1) sensitive parenting, as identified through the MotC manual analysis, is associated with lower levels of child difficulties, and (2) parents classified as sensitive using the MotC manual analysis would also be categorized as authoritative based on the Parenting Styles and Dimensions Questionnaire (PSDQ) self-report measure. Data were collected from two online parenting forums, Reddit and Mumsnet, with a total sample of 100 participants. The Strengths and Difficulties Questionnaire (SDQ) was used to measure child outcomes.
Results supported the first hypothesis, showing that children of parents identified as using sensitive parenting styles (as determined by the MotC manual analysis) exhibited significantly fewer difficulties (F = 20.42, p 0.05). The second hypothesis was also validated, as the Chi-square test revealed a significant association between the MotC manual analysis and the PSDQ scores (χ2 = 4.197, df = 1, 0.05), indicating a high level of agreement between the two measures.
These findings supported the reliability of the MotC manual coding system in identifying sensitive parenting styles from written discourse and highlight the effectiveness of using online data for parenting research. The study also demonstrates the potential of using discourse analysis on online data to provide a scalable and nuanced
approach to understanding parenting behaviors. Future research should validate these findings against long-form MotC interviews to determine the validity and applicability of this method
From Elements to Electronics: Designing Thin Film Perovskite Oxides for Technological Applications
No full textOxide materials provide a wide range of functionalities for today's electronics, from battery cathodes to gate dielectrics. These applications take advantage of unique structural and electronic properties of oxide compounds. In this thesis, I use molecular beam epitaxy to synthesize atomically precise perovskite oxide thin films and characterize the resulting samples with techniques including electrical transport, x-ray diffraction and spectroscopy, and electron microscopy. I focus on the perovskite crystal structure O, a motif that demonstrates an incredibly diverse set of ground states among its members. Specifically, I explore three different perovskite families. I begin with the rare-earth nickelates, where I demonstrate the presence of an antiferromagnetic metal phase accessible via electron doping and further realize a strong antiferromagnetic memory behavior in the compound. Next I turn to a layered Ruddlesden-Popper chromate series where I demonstrate a transition from insulating to metallic behavior and use computational methods to understand the origin of this transition. Finally, I convert bismuthate perovskites to fluorite structures using topotactic fluorination and characterize the functionality of these fluorite compounds as electrolytes in fluoride-ion batteries
Cultural Memory through Tourism: An Ethnography of Colonial Williamsburg.
No full textThis paper examines the relationship between tourism imaginaries and cultural memory through historical sites such as Colonial Williamsburg in Virgina. By analyzing how the museum acts as a tourist destination and an educational institution, this study explores how Colonial Williamsburg serves as a social structure for both concepts through ethnography. Additionally, this paper argues that institutions like Colonial Williamsburg actively shape the collective and cultural memory through tourism. This study highlights the importance of integrating memory studies and tourism imaginaries in understanding the role of historical tourism in preserving and conveying the past
Episodic Liver Injuries Lead to a Long-Term Liver Damage and Molecular Changes
No full textThe liver is the biggest organ in the body that contributes to many vital functions like metabolism, immunity, digestion, and detoxification. The liver is not only capable of regenerating itself after a chemical or surgical injury. It is considered the sewage treatment and the recycling system of the body. Despite these remarkable abilities, chronic liver diseases are well known as one of the biggest threats to public health in the last decade – with their continued expansion across the world. While current models of liver regeneration after an injury have been critical in analyzing some of the liver’s regenerative processes, few models have demonstrated the effect of repeated liver injuries on liver damage and regeneration. To this end, this study created two novel repeated injuries and recovery models - genetic and physiological -in mice to examine how these episodic injuries sensitize the liver to further damage and nonalcoholic fatty liver disease (NAFLD). Both models used repetitive YAP activation to promote these injuries, then allowing for different recovery periods before collecting liver samples for analysis. In the genetic model, Doxycycline (Dox) initiated the injury. In contrast, the physiological model was described by performing partial hepatectomy(PHx) that mimics high-fat diet (HFD) induced injury. The study data showed that repetitive injury increased NAFLD levels in both models. Furthermore, this research expands on the development of NAFDL, which involves decompensation, liver failure, and hepatocellular carcinoma and is accompanied by molecular changes in the hepatocytes and other liver cells, modulating the -inflammation and injury processes. By understanding that these changes are a result of the up-or-down-regulation of the respective genes in the liver cell, this study observed the molecular changes of YAP target genes TEAD1, TEAD4, and JADE 3 to investigate their role in promoting persistence changes during liver recovery. This was done by performing qPCR and evaluating these transcription factors' expression levels during the repetitive injury and recovery periods. The results showed that TEAD4 is expressed during recovery even when YAP is not activated. These results suggest that initial liver injury promotes intrinsic memory so the liver can respond faster to repeated injuries. This finding may carry significant value for public health and liver research, as it may guide research to develop a new therapy that may prevent the progression of liver injury
Constraints on Electromagnetic Parity Violation in the Cosmic Microwave Background using BICEP3
No full textConservation of parity in the electromagnetic (EM) force is a generally accepted assumption for the Standard Model of physics. This need not be true, however, and a number of frameworks have been invented which predict observables in the universe for cases of EM parity violations. For instance, a coupling of the EM Lagrangian with a Chern-Simons term manifests as a frequency-independent rotation of linearly polarized light as it travels through space and is called Cosmic Birefringence. The rotation of light in the presence of Cosmic Birefringence increases over the distance of travel and is thus expected to have the largest rotation from far away objects. As such, the Cosmic Microwave Background (CMB), which is the oldest and farthest source of light in the universe, is a natural candidate in the search for birefringent signatures. The CMB is naturally polarized and can be separated into parity-even and parity-odd (i.e., E-mode and B-mode) polarization states. Under parity violation, this results in a leakage between polarization states in a predictable way. However, this leakage signal as seen in experimental data is degenerate with an incorrect calibration of the polarization response angle of a CMB experiment. Thus, in order to be sensitive to celestial sources of polarization rotation, a CMB experiment must have a precise measurement of the polarization response.
In this thesis, we explore our potential to establish constraints on Cosmic Birefringence using the BICEP3 telescope which measures the linearly polarized light from the CMB at 95 GHz. We break the degeneracy between instrumental systematics and parity-violating physics by characterizing BICEP3's polarization response with respect to gravity using a Rotating Polarized Source (RPS). The RPS is a quasi-thermal and highly polarized source and its co-polar axis is registered with respect to gravity to within 0.09°. The RPS is capable of rotating 360° and we observe the source with BICEP3 at many different rotations of the RPS to derive the orientation of the co-polar axes of BICEP3's ~2000 linearly polarized detectors. We carry out a thorough assessment of the errors in the measured polarization angles, examining a variety of potential sources of systematic uncertainty. Most of the errors are well understood and controlled, with a minimum total statistical + systematic uncertainty of 0.086°. However, empirical benchtop characterization of the RPS's performance suggests there may be a large uncertainty that so far has been difficult to quantify accurately.
We construct an analysis to constrain Cosmic Birefringence by applying angle calibrations to BICEP3's full-year 2017 and 2018 CMB data. The uncertainties on this constraint due to instrument noise and CMB foregrounds are calculated through an extensive suite of end-to-end CMB simulations. In order to maintain a high degree of confidence in the analysis, we blind ourselves to real CMB data and only unblind to certain aspects of the real data when pre-established criteria are met. We are able to progress the analysis to the point where real data is used to complete a number of cross-checks that lend high confidence to calibration techniques. However, as a result of the uncertainty arising from benchtop measurements, we are unable to unblind fully to the birefringence angle. Instead, we establish a mock birefringence constraint for demonstration purposes by substituting a single realization from our suite of CMB simulations in lieu of real CMB data. The calibration techniques we have described in this thesis are shown to have the potential to measure birefringence angles with a precision of 0.13°, which would be the most powerful constraint supported by real telescope data. This potential will be realized in future work with continued advancements in the instrumental calibration, which were dominated entirely by the instrumental error from empirical benchtop measurements. Behind the instrumental systematic uncertainty, our next most limiting uncertainty comes from the statistical noise in our CMB maps. With the inclusion of more CMB data, the precision of future analyses will quickly be limited by extra-galactic gravitational lensing. Therefore, follow-up birefringence analyses will also need to consider CMB delensing techniques before significant improvement on birefringence constraints can be achieved
Exploring Psychological Trauma: Considering Differences in Conceptualization, Exposure, and Growth in Black Americans
No full textIntroduction:
Social sciences scholars are increasingly studying psychological trauma in Black Americans stemming from anti-Black racism. These scholars vary in their methods including developing theoretical models to connect emerging understandings of the Black American experience to psychological knowledge, conceptual models to explain where racial differences may lead to different outcomes compared to White Americans, and empirical investigations to establish the presence and severity of these deeper understandings. These scholars are working in silos without cross-disciplinary collaboration. This dissertation contributes to the scholarly field by systematically synthesizing the findings today from key social science disciplines, investigating the importance of place on select trauma exposures, and synthesizing critical findings to date about Black American experiences of post-traumatic growth.
Methods:
This dissertation includes three investigations into psychological trauma. The first investigation was a meta-narrative review that collated the published literature to date in four traditions of trauma – 1) post-traumatic stress disorder, 2) complex post-traumatic stress disorder, 3) racial trauma, and 4) group-based trauma. The second investigation was an empirical, cross-sectional analysis that examines the association between two measures of neighborhood context and an experience of abuse. The measures of neighborhood include the Home Owners’ Loan Corporation Grade (HOLC/redlining) and the Opportunity Atlas. The measures of abuse include intimate partner violence and child abuse. Finally, the third investigation was a systematic review of the published literature on post-traumatic growth in Black and White populations.
Results:
Our meta-narrative review found the social identity of the defining population and the sociopolitical context important for trauma conceptualization. Across the four traditions of trauma, we found identity and cumulative frequency to be important components to all traditions that are conceptualized and discussed differently. In our empirical investigation, we found our contemporary neighborhood deprivation to be associated with the risk of abuse. Additionally, our stratified analysis found neighborhoods to operate differently between Black and White respondents. In Black respondents, a trend of greater risk of abuse was observed in higher opportunity neighborhoods; meanwhile, in White respondents, a trend of greater isk of abuse was observed in lower opportunity neighborhoods. Finally, our systematic investigation demonstrated that Black Americans have a higher post-traumatic growth score than White Americans when measured at the same time. Racial differences in the underlying belief pathways of post-traumatic growth and racial differences in the subscales that compromise post-traumatic growth, specifically religiosity and social support, require further research.
Conclusion:
As the scope of trauma broadens to understand the impact of colonialism and history on trauma transmission, the field of public health will witness fluctuations and refinement of trauma prevalence rates. These refined understandings should be thoroughly investigated and welcomed as progress to move us toward a more just society
Segmental endothelial cell differentiation – a determinant of T cell trafficking in cancer and viral infections
No full textDuring inflammation, immune cells must rapidly migrate to affected tissues to exert their effector functions. To do so quickly, they utilize the intricate vascular network that interconnects every tissue in our body. The vessels that make up the vascular tree are lined by a heterogenous monolayer of blood endothelial cells (ECs) that regulate various physiological functions necessary for survival. In most settings, leukocyte extravasation is restricted to a particular segment of the vasculature, namely post-capillary venules. This segment is lined by venular ECs (VECs) that are uniquely capable of supporting leukocyte adhesion and extravasation into the surrounding tissue. Here, we explore how CD8+ T cells, an essential immune component in the response against cancer and intracellular pathogens, interact with VECs in various settings. In Chapter 2, we elucidate the contributions of VECs in cancer and show that in addition to healthy tissues, they also mediate T cell extravasation into malignant tissues. In Chapter 3, we find that in settings of acute viral infection, while T cell adhesion is initiated on VECs, some T cells do not extravasate and instead crawl against the direction of blood flow into arterioles, which do not support leukocyte extravasation.
In the tumor microenvironment (TME), pro-angiogenic signals prevent the proper differentiation of ECs, resulting in the macroscopic loss of vascular segmentation. However, single-cell RNA sequencing (scRNAseq) revealed that some tumor ECs (tECs) still acquire a venular transcriptional profile. Here, using atypical chemokine receptor 1 (ACKR1) as a venular marker, we show that the TME maintains ACKR1+ VECs that can support T cell extravasation. Accordingly, tumors with more VECs tend to have a greater abundance of infiltrating T cells. This is of particular importance because, across several cancer indications, increased T cell infiltration can be predictive of responsiveness to various immunotherapeutic approaches, such as immune checkpoint blockade (ICB). Phenotypically, intratumoral VECs acquire an immature phenotype that downregulates key adhesion molecules such as intercellular adhesion molecule 1 (ICAM-1) and P-selectin, while marginal VECs have an activated phenotype with high expression of these adhesion molecules and are in close proximity to infiltrating T cells. Thus, our study is the first to show that VEC abundance and maturity are prerequisites for efficient T cell infiltration into tumors.
Surprisingly, in acute viral infections, after interacting with VECs, some T cells do not transmigrate into the surrounding tissue and instead crawl against the direction of blood flow. To analyze this rheotactic migratory behavior, we developed an interactive web application that streamlines cell track exploration, quantification, and analysis. The Vector-guided Cell Track Analyzer (VeCTA) application enables the alignment of cell tracks with coordinate axes to facilitate directionality analysis in samples restricted by physical barriers, such as the vascular walls. We use this tool to analyze data acquired from intravital 2-photon excitation microscopy and in vitro flow-chamber assays to show that effector CD4+ and CD8+ T-cells preferentially migrate against the direction of fluid flow, often accumulating in arterioles that do not support T cell extravasation.Medical SciencesMedical Science
Consensual Non-monogamy as a Practice, Stigma, and Social Movement
No full textConsensual non-monogamy (CNM) encompasses any relationship(s) in which all parties agree that they can have multiple sexual and/or romantic partners. CNM has seen increased visibility in the form of representation in popular media and even legal gains. This momentum comes as somewhat of a puzzle due to nearly ubiquitous societal mononormativity. Mononormativity refers to the societal phenomena that signal that monogamy is the only “true” or “good” relationship structure, that reward people for being monogamous, and punish them for not. In order to better understand CNM against the backdrop of both increased visibility and pervasive mononormativity, I ask, how do the consensually non-monogamous define their CNM, encounter mononormativity, and legitimate CNM as a social movement? I draw from 44 in-depth, semi-structured interviews with laypeople who practice CNM, and 17 in-depth, semi-structured interviews with key actors in CNM advocacy and/or activism. I supplement the interviews with content analysis of webpages and articles about the work that these key actors perform, as well as books about CNM produced by these actors. I find that most people define their CNM not by sex, but instead by notions of emotional intimacy and morality. Respondents experienced mononormativity in two forms: anticipated stigma, or expectations that others would treat them poorly, and received stigma, or direct experiences of discrimination. CNM activists engage in two main discursive strategies: so-called sexual libertarianism—expressions that sex is positive, joyous, and has multiple meanings beyond showing love in a marital heterosexual context—and what I call familial libertarianism—expressions that families are any unit that provide love, care, and resources, and that there are multiple valid kinds of families beyond two-parent nuclear ones. The findings illustrate the necessity for a sociology of relationships, within which sexualities are housed, that adequately addresses the link between sex and emotionally intimate relationships, be them romantic or familial. The study also reveals mononormativity’s embeddedness in critically important institutions, such as the family, and even to those seemingly unrelated to sex and romance, such as the workplace. Finally, the findings invite us to better theorize the relationship between sexuality and morality, as, rather than trying to decouple morality from sexuality, CNM practitioners assert that their sexual practice is moral
Surviving in the Holocaust: A Transnational History
No full textSurviving in the Holocaust: A Transnational History offers a novel approach to the study of European Jews during World War II, in particular, and victim experiences during genocide and mass violence, in general. Examining over 2,000 testimonies from 15 archives and in 10 languages, this thesis investigates how Jews sought to stay alive in four cities in Western Europe (Marseille, Brussels, Amsterdam, and Copenhagen) and four in Eastern Europe (Kyiv, Lviv, Vilnius, and Kraków). With tools from social and cultural history, I suggest the value of a shift from the outcome (survival) to a social process (surviving), which restores the full spectrum of wartime responses, wide variations in experiences, and a sense of contingency that mass violence would otherwise erase. I argue that no one biographical trait, wartime experience, or factor shaped whether someone lived to see May 8, 1945. Considered as a process, surviving meant all efforts to minimize the growing lack of control, mitigate risks and luck, and halt persecution. While only survivors could speak of survival, every persecuted person experienced elements of surviving that coalesced into an untold story of luck, specific moments of agency, psychological changes, and encounters with others. By dismantling the unwarranted divide between victims and survivors, this dissertation offers the first systematic, interdisciplinary analysis of civilian responses to mass destruction.
Surviving in the Holocaust comprises six chapters. Using a semantic analysis of corpus linguistics, chapter 1 investigates the use of the term “survival” in 4,000 oral histories from the Fortunoff Video Archive, which pioneered the recording of video testimonies about crimes against humanity. In addition to “luck,” three recurring themes emerge: emotional changes, wartime behaviors, and social relations. Chapter 2 delves into the process of personality change that was both universal and intimate. More than trauma, resilience, or the “will to live,” the new concept of the “Holocaust personality” captures best both the deliberate appropriation of new roles and the emergence or reinforcement of character traits after 1939. Surviving meant experiencing a Holocaust personality, whether one survived or not. Paying particular attention to women, chapters 3 and 4 turn to wartime choices and behaviors. More than assimilation, knowledge, or beliefs, it was prior experiences of violence, reflexive distrust of state authorities, and exposure to threats that determined whether a person’s initial response was flight. As the Nazi persecution morphed into mass murder, however, and everyone became a refugee and was hunted down, individual responses to persecution were increasingly leveled by a process that each person underwent at a different pace: the painful coming to terms with local society, the presence or absence of family and loved ones, and the growing threat or first-hand witnessing of Nazi annihilation. Chapter 5 and 6 examine Jews’ perceptions of help and harm. Local populations had more leeway than historians usually admit, but the persecution increasingly interfered with their day-to- day obligations and relationships. To designate all behaviors that furthered or slowed down the persecution, I suggest the concept of “social reactivity,” which diverged from both rescue and resistance in its fleeting, opportunistic, uncoordinated, and inconsistent nature. More than the extremes of perpetration and rescue, it was clearly the local context of Nazi rule, the role of loved ones, and the gaze of fellow citizens that shaped whether Jews experienced help or harm after 1940.
Surviving in the Holocaust makes three key contributions to Holocaust studies, modern European and Jewish history, and the social sciences of violence. First, while Jewish voices have been increasingly integrated into the history of World War II, my research is the first to analyze these personal experiences at a Europe-wide level and to bridge the still prevalent division of Jewish history before and after 1939. My work also weaves Jewish history together with French, Belgian, Dutch, Danish, Polish, Ukrainian, Lithuanian, and Soviet history. Herein lies the second key contribution. Only a transnational perspective offers the necessary depth for understanding the history of Jewish experiences and the societies in which they occurred. Third, my work employs tools from the digital humanities to map Jewish mobility and analyze social encounters and wartime behaviors. Drawing on political science, cultural anthropology, relational sociology, and social psychology, this thesis offers the first systematic analysis of civilian responses to mass destruction across these disciplines
Combinatorial Tasks as Model Systems of Deep Learning
No full textThis dissertation is about a particular style of research. The philosophy of this style is that in order to scientifically understand deep learning, it is fruitful to investigate what happens when neural networks are trained on simple, mathematically well-defined tasks. Even though the training data is simple, the training algorithm can end up producing rich, unexpected results; and understanding these results can shed light on fundamental mysteries of high relevance to contemporary deep learning.
First, we situate this methodological approach in a broader scientific context, discussing and systematizing the role of model systems in science and in the science of deep learning in particular. We then present five intensive case studies, each of which uses a particular combinatorial task as a lens through which to demystify puzzles of deep learning.
The combinatorial tasks employed are sparse Boolean functions, sparse parities, learning finite group operations, performing modular addition, and learning Markov chains in-context. Topics of explanatory interest include the inductive biases of the transformer architecture, the phenomenon of emergent capabilities during training, the nuances of deep learning in the presence of statistical-computational gaps, the tradeoffs between different resources of training, the effect of network width on optimization, the relationship between symmetries in training data and harmonic structure in trained networks, the origins of the mechanisms of in-context learning in transformers, and the influence of spurious solutions on optimization