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Political Functions of Slovene National Mythological Heroes with Regard to the Changing Socio-Political Circumstances and Needs
Get PDFThis article explores how the motif of an ordinary man who confronts a powerful antagonist endangering the community has been used to help achieve national political goals. In 1858, Slovenian writer Fran Levstik wrote the tale of Martin Krpan, a mighty hero who saves the Empire. The character was inspired by the folktale hero Peter Klepec, as well as the medieval knight Gašper Lambergar who saved the Holy Roman Emperor. In the twentieth century, writers retold the tale of Peter Klepec at significant historical moments—on the eve of the breakup of the Habsburg Empire and before and after World War II
Mechanistically Driven Development Of Rhodium-Catalyzed Asymmetric Allylic Amination For -Tertiary Amine Synthesis
No full textForging quaternary stereocenters has long been sought after in the realm of modern synthetic chemistry. Among the fundamental structural motifs in organic chemistry, the synthesis of -tertiary amines poses a surprisingly formidable challenge. Nonetheless, -tertiary amines are privileged structures present myriad of bioactive molecules. A highly effective diene-ligated rhodium catalyst was developed to catalyze the asymmetric allylic amination of tertiary allylic trichloroacetimidates with secondary aliphatic amine nucleophiles. This method offers precise control over regioselectivity and enantioselectivity to furnish -trisubstituted -tertiary amines. The synthetic utility is showcased by efficient preparation of -tertiary amines featuring pharmaceutically relevant secondary amine cores with good yields and excellent selectivities (branched:linear \u3e99:1, up to 99% enantiomeric excess). In depth mechanistic investigations were conducted using synergistic experimental and computational studies. DFT calculations and kinetic experiments showed that the rate of conversion of the less reactive -allyl intermediate to the more reactive isomer via -- interconversion was faster than the rate of nucleophilic attack onto the more reactive intermediate. These data imply that the Curtin-Hammett conditions are met in the amination reaction, thereby leading to dynamic kinetic asymmetric transformation. The thermodynamically more stable -allyl intermediate was found to be kinetically more reactive, leading to the major (S)-enantiomer of the product. Isotopic labeling experiments established that the nucleophilic addition occurs via an outersphere nucleophilic addition with an inversion of -allyl stereochemistry. The observation of complete branched selectivity is noteworthy and as corroborated by computations might be attributed to the hydrogen bonding interactions between -oxygen of allylic substrate and amine-NH that greatly assist the delivery of amine nucleophile onto more hindered internal carbon of the -allyl intermediate. In summary, a robust catalytic approach has been developed for asymmetric construction of tertiary amines that would otherwise be difficult to access under synthetically useful conditions. It is anticipated this protocol would provide an attractive synthetic tool for medicinal chemists to explore new chemical space and develop novel therapeutic drugs
Silk Fibroin - Hyaluronic Acid Nanofibers For Peripheral Nerve Regeneration
Get PDFPeripheral neuropathy is common and is a major source of pain that can lead to debilitating loss of function. Healing often requires medical intervention through autologous nerve grafts. However, autografting is not always successful and can lead to increased debilitation through donor site morbidity. Tissue engineering seeks to improve nerve injury treatment though the use of nerve conduits. Conduits made from functional biomaterials can be implanted into a nerve injury site encouraging and controlling axonal regrowth without causing additional harm to the patient. Both silk fibroin (SF) and hyaluronic acid (HA) have proven successful in the field of neural tissue engineering. SF has excellent mechanical properties and is attractive to cells. HA is familiar to cells and has proven successful in peripheral nerve regeneration. This study developed aligned combination SF-HA nanofibers through electrospinning that could be used within a nerve conduit. Both materials were also methacrylated to allow for photocrosslinking and additional control over material properties. SF-HA was tested alongside a material containing only HA that has already proven to be effective in literature. When characterizing the materials, it was found that through chemical methacrylation HA was substituted at 60% while SF reported a 30% substitution. Electrospun SF-HA nanofibers were found to have a greater diameter than HA fibers; however, SF-HA was found to be more aligned with greater surface hydrophobicity. Mechanically, it was found that both materials exceeded the properties of the native tissue, but SF-HA far exceeded HA in elasticity and overall fiber extension. Furthermore, human Schwann cells attached, proliferated, and released more pro-regenerative growth factors on SF-HA than HA. Dorsal root ganglia neurons also displayed a healthier cell morphology with longer neurite extensions on SF-HA fibers. Therefore, SF-HA nanofibers have potential as a nerve conduit material
A Phenomenological Study Of Black Journalists’ Communication Strategies When Posting About Contentious News Topics On Social Media
No full textIt is problematic to expect that professionals uniformly approach journalism or its daily routine of social media engagement. The events of Summer 2020 centered this issue for Black journalists as protests erupted around the world in protests against police brutality in the United States. This contentious time charted a path for research to explore what steers the decision-making of Black journalists considering participating in conversations on social media about those protests and their contiguous matters, such as race, politics, social justice, and gender. As disputes about social media policies continue to arise between news organizations and the Black journalists they employ, this research explores how they navigate occupying the spaces of race and profession.
Drawing on 31 in-depth interviews with Black journalists working in or near large U.S. cities, this project used co-cultural theory, the professional identity and ideology of journalists, and ventriloquism theory to understand what journalists consider when contemplating engaging in social media conversations about contentious topics. Participants described 11 social media posting strategies: yielding, avoidance, circumspection, moxie, grouping, strategic inquisition, modification, veiling, suppression, compliance, and expungement.
Black journalists invoked these strategies for various reasons, including holding space for marginalized voices; safeguarding their employment; demonstrating their right to post as an individual based on experience; leaning on plausible deniability when necessary; witnessing conversations taking place online without taking up the risks that come with participating in them; abiding by implicit and explicit rules of news organizations and the wider journalism industry; and avoiding the social media spotlight
Exploring Counseling Experiences Of Arab Americans: A Grounded Theory Study
No full textThis qualitative grounded research study explores the experiences of counseling among Arab American individuals, aiming to shed light on their unique perspectives, challenges, and coping strategies within the counseling process. Through in-depth interviews and thematic analysis, 11 individuals were interviewed. The study highlights the complexities of Arab American clients\u27 interactions with counselors, their perceptions of therapy, and the influence of cultural norms and values on help-seeking behaviors. Findings reveal multi-layered themes encompassing cultural identity negotiation, stigma associated with mental health, barriers to access and utilization of counseling services, as well as the importance of cultural competence and rapport-building in therapeutic relationships. The study contributes to the existing literature on multicultural counseling by amplifying the voices of Arab American individuals and elucidating the cultural nuances that impact their therapeutic journeys. The implications of this research extend to counseling practice, education, and policy development, and fostering greater awareness
Investigating Saudi Arabia Biology Teachers’ Perceptions Of Scientific Inquiry Abilities And Digital Learning Technologies Fluency
No full textAbstractThis mixed-methods study aimed to investigate the effectiveness of the technology-embedded scientific inquiry (TESI) model on teachers’ and students’ scientific inquiry abilities and digital learning technologies fluency to enhance science education learning outcomes. The TESI framework guided the construction and execution of this study. The quantitative design for this research is a pretest-posttest control group experimental research. A total of 40 teachers and 800 students from Tabuk high schools in Saudi Arabia over 12 weeks participated in the quantitative study. Twenty teachers and 400 students constituted each of the two experimental groups, control, and treatment groups. The intervention for this study was the two-week professional development workshop provided to biology teachers. Note that the researcher delivered the two-week intervention only for the experimental group of teachers (n=20). Further, students who received instruction from teachers that completed the two weeks intervention comprised the students’ segment of the experimental group (n=400). The researcher performed multivariate analysis of covariance (MANCOVA) and identified a statistically significant positive effect: using digital learning technologies in biology instruction to enhance teachers’ and students’ scientific inquiry abilities and digital learning technologies fluency. MANCOVA examines differences between participants of the experimental (N teachers=20, N students=400) and control group (teachers=N=20, students=N=400) concerning scientific inquiry abilities and digital learning technologies fluency. Results of the MANCOVA analyses (p\u3c0.001) indicated that the intervention significantly impacted students’ and teachers’ scientific inquiry ability and digital learning technologies fluency. The qualitative evidence gathered from in-depth interviews with the experimental group teachers supports the quantitative findings. Teachers’ excerpts from interviews demonstrated clear improvements in the experimental group teachers’ and students’ scientific inquiry abilities and digital learning tools fluency. The results imply that the TESI model improves science learning outcomes for teachers and students
Triumphantly Taking Tenure: Reflections Of Black Women Faculty In Higher Education
No full textThis qualitative study focuses on the tenure experiences of Black women faculty who have attained tenure at predominately White institutions of higher education. Black Feminist Theory, Endarkened Feminist Epistemology, and Identity Taxation create theoretical lenses and frameworks for this study. Methodologically, this study uses sister circles and analyzes data through narrative inquiry, looking at the experiences of Black women faculty across various disciplines while they were on the tenure track. This study aims to share the dueling stories of triumph, strength, and endurance while increasing awareness about the marginalization and multiple oppressions that Black women Faculty have withstood while pursuing the professoriate
Advances In Control Strategies For Cyberphysical Systems Incorporating Quantum Computing, High-Fidelity Simulation Methods, And Space Communication Concerns
Get PDFContinuing advances and new applications in manufacturing and the systems engineering field lead to increased demands on controllers, models, simulation tools, and computer systems. Utilizing these new technologies can have profound consequences on control of the physical system itself, and the interactions between these aspects will need to be understood to ensure economic efficiency, safety, and secure operation. It is not always clear how implementing new technologies will impact the control of a process, especially when the modes of operation of the technology or the process itself are unusual or unknown. To address this, the work presented in this thesis considers this topic from several aspects. We focus on describing new modeling and simulation techniques, the implementation of a new kind of computer technology (quantum computing), and control of manufacturing in novel areas (e.g., in space applications).
First, we look to modeling techniques to demonstrate how several high-fidelity simulation and test bed methods can be utilized to improve controller operation, understand processes at a deeper level, and predict the consequences of cyberattacks on the structural elements of the process. There are three simulated processes in this work. The first is a simulation of a steam methane reforming reactor, which produces hydrogen from mostly methane and water vapor; the second process is powder bed fusion, which is an additive manufacturing method that creates metal objects by melting successive layers in a bed of powder; and the third is a greenhouse supplemental lighting control system. With these simulations, we elucidate understanding of how to simulate new model-based control strategies relating to the physical structure of the process, how to utilize different software for accomplishing the simulation of controllers, how to represent unusual operation such as cyberattacks on controllers, and how to use such models for increasing knowledge of a process.
Secondly, given increased interest in quantum computers, we discuss the implementation of control algorithms on quantum devices. Quantum computers utilize concepts from quantum mechanics, such as superposition and entanglement, to perform operations in new and potentially useful ways. Because of the unique ways in which quantum computers operate, which may introduce effects such as non-determinism and rounding, we consider how the operation of a controller may need to be changed to ensure safe operation of a process. To study this, we perform a theoretical analysis to study rounding effects using Lyapunov-based economic model predictive control (LEMPC), which is an advanced model-based control strategy, as well as practical aspects such as ensuring safe operation given non-deterministic controller operation. Additionally, to gain any advantage on quantum computers, quantum algorithms will need to operate in fundamentally new ways. We discuss how a controller might be implemented, to demonstrate how a controller might be non-deterministic, and we discuss the use of a quantum amplitude amplification algorithm for solving the optimization problem in a model-based controller, utilizing a specific single-input single-output system as a case study.
Finally, the last topic discussed in this thesis relates to the control of space manufacturing. Given the lengthy distances in space, it is likely necessary to have on-site manufacturing capabilities to ensure the safety and flexibility of long-term missions. Given the ample computational power available on Earth, it may be desired to utilize these resources for performing advanced control computations involving modeling or optimization for a process located in space. In this case, the significant distances in space would also impact control operation. To address this, we perform a LEMPC theoretical analysis considering communication delay, which occurs in two directions, as well as a discussion of how controllers and processes might be modified to account for such delays. The final topic in this section discusses challenges in reducing communication time, specifically by looking at quantum entanglement. Through a series of proposed methods, we describe how the communication delay will not be overcome and will remain a challenge for space-based control
Surveilling Black Muliebrity At A Historically White Urban R1 Institution
No full textABSTRACT
This sequential explanatory study focuses on two forms of sight: Sankofa (hindsight) and Surveillance (close observation or monitoring (Foucault, 1995, 2000; Temple, 2010; Quarcoo 1972). These two ways of seeing can provide a unique perspective on Black women’s career experiences in historically white institutions. I focus on how European intellectual systems “sort” Black women via surveil-lance (Lyon, 2003; McKittrick, 2006). Through the lens of Plantation Politics— a theoretical framework that attempts to unpack the lived experiences of Black people whose ancestors were enslaved as part of the transatlantic slave trade—this study seeks to understand the interactions between Black women’s labor and the institution of higher education (Squire, 2021; Williams and Tuitt, 2021). Critical narrative inquiry guides this research as I use cookhouse conversations to glimpse into the professional lives of Black women working at historically white institutions. It is hoped that this insight will help guide more inclusive processes surrounding opportunities for career advancement such as hiring, internal promotions, mentoring programs
Mutual Recognitions Across Generations
Get PDF“Sovereignty,” Arendt says, “is contradictory to” the human condition. It is not, in any event, the kind of thing that can be shared across generations. Subsequent generations lack sovereignty to the precise degree that they are bound by the decisions of their predecessors. It is no answer to say that contemporary citizens participate in the sovereignty of a whole, transgenerational people. To paraphrase de Tocqueville, later generations are not free because they are not entirely equal, and they are not equal because they are not entirely free.
Where “sovereignty” is a metaphysical concept that transcends time, recognition is an act of the imagination that extends empathy diachronically in both directions. An earlier generation treats its successors with recognition and respect by bequeathing the best system it can manage and entrusting later generations to exercise the same freedom that it enjoyed. Democratic law can exist across generations only through negation. Later citizens may accept as valid the law made by their predecessors. But, in doing so, they implicitly affirm their right to alter, amend, or abolish what came before. Only by freely affirming the choices of their predecessors can current citizens participate in something approaching freedom