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Exploration of mild and selective hydrozirconation reactions facilitated by zirconocene hydride catalysts generated in Situ.
No full textMetal hydride reagents are widely used in organic synthesis for the reductive functionalization of π-systems. In recent decades, the surging cost of precious transition metals has prompted the search for alternative hydrometalation approaches, especially innovative methods using first-row and early transition metal catalysis. Analogously, the use of zirconium is appealing because it is earth-abundant, has low associated toxicity, and is often is less costly than late transition metals. We sought to (i) develop reaction conditions that facilitate the conversion of oxozirconocenes to ZrH catalysts using hydrosilanes and (ii) identitfy a mild strategy for the preparation of a ZrH catalyst using Cp2ZrCl2 as a precatalyst. After establishing a general platform for ZrH catalyst generation and its efficient turnover, we successfully showcased its application towards the reduction of carbonyl-containing substrates (ketones, aldehydes, enones, lactones). Then, we extended this manifold to achieve the catalytic partial reduction of 2° amides and the partial reductive transamination of 3° amides. These findings guided our later studies on the direct catalytic conversion of esters to imines and enamines. In addition to carbonyl reduction, we have utilized ZrH catalysis to achieve the catalytic partial hydrogenation of alkynes. Ongoing work expands this catalytic protocol to novel redox-economical transformations enabled by synergistic Zr/Pd catalysis, including unprecedented deoxygenative cross-couplings of carbonyl containing functional groups and strategies for alkyne hydroarylation
Negotiating the memory of the dead in the community of Yehud.
No full textResearch in the material culture and texts of the Persian period Levant has provided greater understanding of the early second temple communities and identity formation. However, studies regarding mortuary practices and the role of the dead among these communities are limited. Through the lens of social memory theory, I examine the relationship between postexilic communities and their ancestral tombs. An analysis of the landscape for these communities, including the relationship between settlement and necroscape, provides a better understanding of the context within which burials are referenced in the biblical text.
Furthermore, by viewing postexilic burial references as sites of memory, we can gain a greater appreciation for the developing memory and identity of the respective communities behind the texts. These references are found in the Books of Kings, Ezekiel, Chronicles, and Nehemiah. The burial references indicate the importance of monarchic Jerusalem and its royal mortuary cult. Each book, however, demonstrates different approaches to the memory of the royal dead and distinct ways in which that memory influences (and is influenced by) the identity of that community. Ultimately, I argue that burial references in the postexilic biblical texts are sites of memory and reference the royal mortuary cult. The manner in which these sites of memory are incorporated in the text indicate deliberate literary choices influenced by the socialized, and idealized, memory of the monarchic era landscape as well as by the existing landscape of the authors, particularly the persistence and accessibility of nearby tombs
The language of early-stage entrepreneurship : strategic communication in venture evaluation contexts.
No full textEarly-stage ventures must persuade resource holders with limited information and brief interactions, making language a critical yet underexamined factor in entrepreneurial success. This dissertation examines how language complexity, adaptability, and alignment influence investor evaluations in venture competitions. Using computational text analysis and statistical modeling, the study assesses whether clarity improves perceived competence, whether entrepreneurs’ framing of the venture path and direction signals adaptability, and whether linguistic convergence with investors enhances funding outcomes. The findings show that simplified language, strategic narrative framing, and alignment with stakeholder discourse improve evaluations. Language emerges as a strategic asset used to signal legitimacy, reduce perceived risk, and mobilize support. The research offers scalable tools for analyzing entrepreneurial communication and provides a framework for understanding how founders craft messages to align with evaluators and secure early-stage resources
Take heed what ye hear : Shakespeare's "Measure for measure" and the Bible.
No full textThis dissertation explicates Shakespeare’s allusions to Christian Scripture in Measure for Measure, his most biblical play. It takes the play as Shakespeare’s sincere response to his new king and patron’s well-known aspiration to be a “good textuary” of the Bible. Working through a network of biblical texts connected to Jesus’ Sermon on the Mount and Paul’s letter to the Romans, the play questions the coherence of even a well-meaning Christianity backed by the power of “the sword.” As a surrogate for the playwright, the Duke of Vienna’s attempted figuration of Christ is compromised by his willingness to coerce a comic ending through surveillance and crime prevention.
Chapter Two places Measure for Measure in conversation with Othello, the play which immediately preceded it and with which it shares a source. It also argues that Shakespeare alters the plot of his source material in light of Jesus’ “Ye have heard it said…but I say unto you” sayings in the Sermon on the Mount. Chapter Three defers discussion of Matthew 7.1-2—commonly considered Measure for Measure’s titular verses—to consider the context of hypocrisy in the larger biblical paragraph (7.1-5) and its relevance to the play’s villain. Chapter ii Four examines the justice-oriented language of “measure,” not only in Matthew 7.1-2, but throughout the Bible, and how that language is deployed in the play. Chapter Five considers a network of Gospel texts connected to the play’s first and last conspicuous references to the Sermon on the Mount. Chapter Six thinks through allusions to Romans 7 (and its neighboring chapters) in Angelo’s conversations with Isabella and elsewhere. Chapter Seven looks at the play’s references to Romans 13’s “sword,” particularly its embodiment in Abhorson the executioner. And finally, Chapter Eight concludes the dissertation with a reading of the Duke as figuring Christ
Safe and robust neural architecture via limiting the activation potential of neurons with rectified linear units.
No full textThe widespread use of deep learning models in critical fields such as healthcare and autonomous transportation underlines the necessity for robust security against adversarial examples — inputs deliberately modified to mislead models. Despite superior performance in many tasks, these models are vulnerable to attacks that compromise safety. Previous defense strategies, including adversarial training and gradient masking, have proven either computationally intense or partially effective. This research targets the susceptibility inherent in the ReLU activation functions, proposing custom modifications intended to bolster model defense without affecting performance. Our evaluations across various datasets indicate improved robustness, showcasing the efficacy of these architectural enhancements in mitigating adversarial vulnerabilities
Exploring the community cultural wealth and persistence of Latino male students at a two-year Hispanic serving institution.
No full textLow educational outcomes for Latino males, measured through persistence and degree attainment rates at two-year Hispanic-Serving Institutions (HSIs), are a significant postsecondary educational, societal, and workforce issue. A variety of complex factors at the student and institutional levels contribute to these low rates, especially at two-year HSIs that often need to recognize and leverage Latino males' cultural strengths fully. As many traditional persistence models lack the cultural aspects for Latino students, I used an asset-based theoretical framework to explore persistence in this study. This qualitative single-case study explored how Latino males use their cultural wealth to persist at a single HSI community college in the Southwestern United States. I used Yosso's (2005) community cultural wealth model to understand the participants' persistence experiences. The community cultural wealth model has six forms of cultural capital: aspirational, linguistic, navigational, social, familial, and resistant. I collected data through participant questionnaires, semi-structured interviews, and documents from the research site. The data analysis revealed that participants used each form of cultural capital to support their persistence. Commitments to family, educational values, and career goals drove aspirational capital. Bilingual abilities helped them form supportive relationships and enhance their academic focus creating linguistic capital. Using academic support services and building relationships with mentors were components of their navigational capital. Involvement in college activities and on-campus employment developed social capital. Life lessons and various forms of support from their families formed familial capital. One Latino male used resistant capital in a self-advocacy situation to overcome discrimination. Key decision-makers, including HSI administrators, faculty, staff, families, and Latino male students, can use these findings to implement strategies that enhance Latino male persistence and degree attainment. While the Latino males in this study successfully persisted from their first year to their second year using their cultural wealth, the complexities of the persistence and degree attainment phenomena call for more research. I recommend further research to expand on these findings and explore the long-term effects of cultural capital on Latino male success across different postsecondary educational contexts
Depositional and post-depositional controls on reservoir quality and performance within the early Jurassic Nordegg Member, southern Alberta, Canada.
No full textThis study provides insight into the depositional and post depositional controls on Early Jurassic reservoir quality and distribution and how they relate to trends of hydrocarbon production across the northern portion of the Nordegg carbonate shelf of south-central Alberta, Canada. The Nordegg Member is unconformably overlain by an unidentified marine intertidal quartz sandstone (i.e., “unidentified” Jurassic sandstone) across the western portion of the platform. The Early Jurassic stratigraphic succession dips structurally westward and is truncated beneath an angular unconformity overlain by fluvial siliciclastics of the Early Cretaceous Lower Mannville Formation. Nordegg shelf carbonates beneath the unconformity surface within the eastern portion of the study area are extensively karst modified and consists of highly fractured collapse breccias admixed with Lower Mannville siliciclastics. The highest maximum daily and cumulative gas production values are associated with both the undifferentiated Jurassic sandstone in the west and karsted Nordegg shelf carbonates to the east
I've got a bad feeling about this : revolutions on the home screen.
No full textThe thesis covers mediated fictional revolutions in film and TV and how those revolutions shape and support neoliberalism. Specifically looking at The Hunger Games, Black Panther, and the TV show Andor the paper shows how neoliberal support, and opposition takes a multitude of forms in each that articulate how the American imaginary views revolutionary praxis. While some reconstitute neoliberal ideology there exists the potential for producers, directors, and screenwriters to create projects that meaningfully articulate revolutionary resistance. While the core focus of the paper is on figures who are outwardly revolutionaries, the larger task is to compare and contrast media about revolutions to test their revolutionary potential
Development of network-scale intercomparison techniques and sampling platforms for the black and brown carbon (BC2) aerosol optical network.
No full textCharacterization of aerosols as drivers of climate and air quality through ground-based measurements is exceedingly important, and filter-based absorption photometers are a widely accepted means of deriving the composition and concentration of absorbing aerosols. This study presents data from a collocation of 15 Tricolor Absorption Photometers (TAPs) from the BC2 monitoring network to validate comparability between instruments, while also providing practical considerations for field usage and detailing the development of the sampling infrastructure used for operation. TAPs were correlated via orthogonal regression with a modified goodness-of-fit measure, R2g. Analysis showed distinct "α" and "β" groups offset by a ~50% difference in sensitivity while conserving linearity (R2g = 0.90 - 1.00 in >90% of regressions), revealing a systemic manufacturing defect. Intercomparisons at multiple flow rates and transmittance ranges were consistent with previous studies. Data collected within this study highlights the need for further large-scale, single-instrument intercomparison studies across multiple production periods
Investigations into the roles of chemical receptors on the behavioral ecology of the yellow fever mosquito, Aedes aegypti.
No full textInsects are the most biodiverse class in Animalia and have a profound impact on the globe. Many insects engage in destructive behaviors, including crop destruction and disease transmission. These behaviors are primarily mediated via olfaction. Insect olfactory organs include the antennae, maxillary palps, and labella, which are coated with hair-like structures called sensilla. Each sensillum houses the dendrites of one or more olfactory sensory neurons, which are surrounded by sensillar lymph. Odorant Binding Proteins (OBPs) solubilize ligands and transport them to the dendrites. There, ligand-gated ion channels can detect ligands and open in response, leading to action potentials being sent to the antennal lobe for olfactory processing. Olfactory receptors fall into two broad categories: odorant receptors (ORs) and ionotropic receptors (IRs). Gustatory receptors (GRs), another class of chemoreceptors, primarily mediate contact perception, though they are occasionally involved in olfaction. While both chemoreceptor classes are ligand-gated ion channels, they differ in their structure, ligand selectivity, sensillar localization, and antennal lobe glomerular targets. IRs were discovered more recently than ORs, and the body of knowledge is rapidly growing. However, a need was identified for a thorough review that synthesizes the discoveries in Lepidopterans and Dipterans. We review carboxylic acid detection mediated by the IR75 in both insect orders. We also present updated annotations for the IR75 subfamily gene, as well as phylogenetic analysis and gene structure analysis. Next, we examined the role of chemoreceptor co-receptors in tuning receptor expression. Both IRs and ORs are comprised of one or more co-receptors and many tuning receptors. The co-receptors do not bind to ligands but form an essential part of the pore complex. We sought to understand the effects of co-receptor knockout on tuning receptor expression in Aedes aegypti. To this end, we analyzed the antennal transcriptomes of co-receptor knockout mutants. We found that co-receptor knockout results in significantly reduced expression of cognate tuning receptors. Finally, we present interesting data from an in-silico analysis of OBP expression in maxillary palps, postulating that the OBPs most highly expressed in this organ serve a non-olfactory function