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Host-virus Interaction Dynamics Using Sulfolobus Spindle-shaped Virus and Host Sulfolobales System
No full textThe Sulfolobus Spindle-shaped virus (SSV) is among the most studied archaeal viruses, particularly in extreme environments. This virus predominantly infects multiple Crenarchaea from the Sulfolobaceae family. These hosts thrive in extreme environmental conditions, such as sulfuric hot springs, with a pH of 2 to 4 and a temperature of 76-80˚C. Sulfolobales exhibit a wide geographical distribution across volcanic hot springs. The Sulfolobus Spindle-shaped Virus (SSV), encompassing strains such as SSV1 and SSV8, employs a non-lytic replication strategy in hosts belonging to the order Sulfolobales. The SSV-Sulfolobales system can be cultured in liquid and gellan gum solid media. A comprehensive study has been performed to determine the host range of a specific SSV type and identify the hosts susceptible to SSV infection. This study examines the multiple methods used in SSV titering and the impact of each virus particle count technique on the interactions between single viruses and single hosts (SVSH) across multiple sympatric and allopatric host-virus pairs. This involves conducting proteomic analysis, such as the regulation of heat shock proteins (HSP) of the host after each round of SVSH infection. This study focuses on two viruses: a low-virulence strain (SSV1) and a highly virulent strain (SSV8), which infect hosts of the Sulfolobales from various biogeographic regions. SSV infection in Sulfolobales hosts resulted in growth inhibition; hence, SSV infection may potentially serve as an environmental stressor on hosts and regulate Archaeal group II chaperonins (also known as Heat Shock Proteins). This study focuses on the transcriptomic and proteomic regulation of Heat Shock Proteins in the S. solfataricus P2 strain infected with SSVs (e.g., SSV1 and SSV8). It compares the outcomes with those of uninfected controls to explore whether viral infection induces sufficient stress to upregulate Heat Shock Proteins (HSPs). This dissertation elucidates how variations in elemental mass influence elemental stoichiometry, which, in turn, can either promote host growth or facilitate virus propagation by using the SVSH on S. islandicus (both natural and cured strain) infected with SSV1 and SSV8. This pivotal research will explore previously uncharted territories and a positive correlation between relative virulence and elemental stoichiometry in stably SSV-infected Sulfolobales. One of the future aspects of this study will be to complement the genomic and transcriptomic analysis of both the host and the virus, which may contribute to providing a definitive understanding of their differential interactions. Key Words: Sulfolobales, Sulfolobus Spindle-shaped Virus (SSV), Crenarchaea, SVSH, heat shock proteins, infection dynamics, relative virulence
Synthesis, Structural Characterization and Optical Studies of Silver-Indium-(Zinc)-Chalcogenide Fluorescent Quantum Dots
No full textDeveloping a non-toxic, high-performance fluorescent nanomaterial is crucial for overcoming the environmental and health restrictions of current cadmium, and lead based quantum dots (QDs), which limit the application of quantum dots in optoelectronics and bioimaging. In this thesis, we synthesized environmentally friendly AgInS2 QDs by a colloidal method, systematically altering the In/Ag precursor ratio from 2 to 6 to study the impact on their optical and photophysical properties. Our goals were to find the optimal stoichiometry for maximum quantum efficiency and stability. We also investigated further improving optical and photophysical properties through shelling with ZnS. The emission spectra appeared broad, but the full width at half maximum (FWHM) decreased from 173 nm to 124 nm when the In/Ag ratio increased from 2 to 6. The quantum yield reached a maximum of 48.57% at In/Ag = 4, beyond what had previously been reported for these QDs. Time-resolved PL revealed that this combination had a remarkably long fluorescence lifetime of 273.08 nm. Next, adding a shell of ZnS increased the QY to 69.6%, while the FWHM reduced to 118 nm. The non-radiative rate constant (knr) ranges from 1.98 × 106 s-1 to 5.03 × 106 s-1 , whereas the radiative rate constant (kr) ranges from 3.85 × 105 s-1 to 1.68 × 106 s-1. Furthermore, single particle fluorescence experiments demonstrated that the shelled QDs were stable, showing blinking significantly less than unshelled QDs. This study shows the importance of using the proper ratio of In/Ag to reduce non-radiative decay and further using a ZnS shell to optimize AgInS2 QDs. Fixing the In/Ag ratio at 4 and adding a shell resulted a high quantum yield of almost 70%, addressing the long-standing problem of low brightness in Cd-free QDs. The finding presents a reproducible technique for creating high efficiency luminescence without using harmful materials. While no device construction or modeling was done, improved stability, reduced blinking, and increased radiative efficiency clearly suggest that these QDs have the potential for future applications in environmentally friendly technologies such as bioimaging or light- emitting devices
Layered Redactions: An Arts Based Research and Self Study Handbook for Art Teachers Navigating Professional Learning Communities
No full textThis self-study contributes to the field of art education by examining the tensions and possibilities within Professional Learning Communities (PLCs) through an arts-based lens. Framed as both a love letter and a palimpsestic work, this thesis reimagines professional development as a layered, living practice, rooted in collective care and criticality. Using collage as both method and metaphor, the study interweaves Freire’s dialogic praxis, bell hooks’ radical tenderness, and the marginalia of a weathered PLC handbook—redacted, annotated, and reassembled with lived experience. Through deliberate redaction and reassembly, the research intentionally disrupts the normative invisibility of whiteness in educational structures, making visible how white-centered pedagogies both shape and constrain professional development frameworks. In the interstices of mandated compliance, the author traces the spectral presence of singleton art teachers navigating standardization amid histories of segregation and systemic inequity. Visual journals, sewn texts, and altered documents become data, resisting rubric-driven metrics in favor of relational, rhizomatic learning. The redactions illuminate rather than erase, exposing how authentic professional growth often emerges in the unrecorded, artful exchanges between educators. Through this creative-critical inquiry, the thesis reveals that the most vital learning lives in the crease between critique and creation—in shared materials, in whispered resistance, and in the courage to imagine otherwise
Evaporating Natural Parent Childcare Liberties Under New Parentage Laws
Get PDFThis Article explores the evaporating Due Process interests of natural childcare parents who are not unfit and who do not knowingly consent to diminished childcare liberties when the state recognizes new nonadoptive and nonbiological parents. Childcare liberty losses need not involve neglect or comparable bad acts rendering a parent unfit. They need not involve consent, actual or implied, by an adversely affected parent. On the new forms of nonadoptive and nonbiological childcare parents, the most recent UPAs and their state counterparts are illustrative. They recognize parentage in an individual who resides with and holds out a child as the individual’s own “for the first two years of the life of the child.” That individual can effectively replace a fit, existing, and nonconsenting parent by judicial decree. Comparably, the 2017 UPA recognizes that a de facto parent, without adoptive or biological ties, can then replace an existing fit parent. Further, nonadoptive and nonbiological parents can also effectively displace natural parents via new forms of voluntary parentage acknowledgments. This Article also explores Due Process liberty issues arising with the new forms of parentage under the United States Supreme Court decision in Lehr v. Robertson. There, as noted, the Court recognized that a “natural father [has] an opportunity that no other male possesses to develop a relationship with his offspring.”
This opportunity interest in childcare parentage has been extended to at least some “natural” mothers (i.e., egg donors who are not gestating parents). The new parentage forms can negate the parental opportunity liberty interests of some expecting natural parents, including sperm or egg providers. Upon reviewing the new parenthood forms and their current federal and state law limits, this Article concludes with reflections on the need for greater legal protections for existing and expecting natural childcare parents when new forms of nonadoptive and nonbiological childcare parenthood are undertaken. Further, this Article demonstrates how to better safeguard the childcare liberties of natural parents
The IDEA of Inclusivity: The Fallacy of School Choice
Get PDFAs calls for reform in public education grow, students with disabilities have become the poster children for a failing system that is not equipped to handle students’ varying needs. With the number of children receiving services for learning disabilities growing, some argue that the current system not only is failing to provide students with appropriate education but is actively causing harm. Issues gaining adequate funding, disparities in educational access to racial minorities, and failure to adhere to federal mandates have made it difficult for public schools to meet the individualized needs of all students, particularly students with disabilities. One example is the LEARNS Act in Arkansas, which expands access to vouchers including for students with disabilities. However, voucher programs often require families to waive rights under the Individuals with Disabilities Education Act (IDEA), including access to free, appropriate public education and the least restrictive environment. This Article will explore the potential federal claims that students with disabilities may have as well as legal arguments to compel states that have subsidized education to, at a minimum, guarantee students with disabilities their federal rights, including relevant legal history of the rights of students with disabilities under federal statutes, an overview of voucher programs and their challenges, and an evaluation of the LEARNS Act in Arkansas under the Constitution that students with disabilities could make to invalidate private schools’ discriminatory admission policies as well as the denial of their federally-guaranteed rights under the state-action doctrine
The Relationship Between Food Allergies and Intolerances and the Development of Disordered Eating Patterns
Get PDFFood allergies and food intolerances are becoming an increasingly more prevalent issue in the Unites States. To mitigate adverse reactions, these individuals often eliminate food or food groups from their diets and the ramifications of these lifestyle changes may result in disordered eating patterns. In regard to food allergies and intolerances and eating disorders, it is reasonable to suggest that the overlapping lifestyle choices and physical, social, and emotional ramifications may lead to a correlation between the two phenomena. This study explores the relationship between food allergic and food intolerant individuals and disordered eating habits among college students. Survey results from this study found a positive correlation between avoiding food and disordered eating patterns, which indicates a need to explore further relationships between diet elimination and disordered eating patterns among college students