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Assessing the Nature of Science: Implications for Framing and Evaluation
Get PDFSteadfast across the competing science education reform efforts has been the call for accurate teaching and learning of the Nature of Science (NOS). However, which NOS ideas should be taught, to what depth, and what order has remained elusive. Study 1 of this dissertation examines the history of NOS assessment efforts to glean insight into the historical answers to the questions. The findings call for caution in the science education community as the foregrounding of particular NOS ideas may imply a soft, less certain perception of scientific knowledge and, thus, unwarranted skepticism. As the field of science education advances and curricular priorities are revisited, NOS advocates must carefully consider the ideas they foreground.
Promoting functional scientific literacy among the public, of which accurate NOS understanding is a component, is a consistent aim of science education. Scientific literacy encompasses knowledge, abilities, and values necessary to address science-related issues. This supports the selection of concepts and contexts relevant to everyday life. Study 2 of this dissertation investigates the vaccine hesitancy SSI to determine which NOS ideas are relevant in vaccine decision-making. While knowledge alone is not sufficient to change behavior, and the NOS is a body of knowledge, this study puts forward NOS ideas/issues that may impact justifications for vaccine hesitancy. The NOS ideas/issues most important for a selected SSI have implications for messaging surrounding that issue, but also for science education. The findings of the second study mark the beginning of a NOS curriculum with priorities justified by relevance to socioscientific decision-making.
SSI are complex issues with underlying sociocultural and emotive factors. Assessing the role of the NOS within these complex issues requires a research instrument capable of producing measures that permit valid and reliable inferences of NOS perceptions in large-scale studies. Study 3 of this dissertation developed and piloted a short pragmatic forced-choice item survey targeting a single NOS construct. This study provides a line of research necessary for these large-scale studies and for the empirical validation of SSI-NOS models like that proposed in Study 2
Understanding Spermiogenesis as a Biomolecular System: The Importance and Roles of Testis-Specific Actin-Related Proteins in Male Fertility
No full textSpermatid morphogenesis is a crucial phase in spermatogenesis that underpins male fertility. Despite the well-established roles of actin and actin-related proteins (ARPs) in somatic cellular processes, their specific involvement in spermatid development has remained enigmatic. This study delves into the roles of two testis-specific ARPs, ACTL7A and ACTL7B. Using knockout mouse models, transcriptomics, proteomics, mammalian cell cultures, and in silico models, we have uncovered their roles in cytoskeletal regulation, and their involvement in nucleosome remodeling and gene expression.
Both ACTL7A and ACTL7B are predominantly localized in the subacrosomal space of spermatids. Loss of either protein resulted in acrosomal detachment, with Actl7a knockout mice exhibiting a more severe acrosomal phenotype and ultimately being found responsible for the formation of the entire subacrosomal F-actin network. In contrast, ACTL7B relocated to the manchette during elongation, and its loss led to manchette detachment, hyperacetylation, and reduced association with HDAC6, a tubulin deacetylase.
Furthermore, both ACTL7A and ACTL7B were observed in the intranuclear space of spermatocytes and round spermatids. ACTL7B ablation caused various transcriptional changes, including an increase in genes related to protease inhibition, cell death, extracellular matrix regulation, and immune responses, along with changes in germline-specific transcription factors and a severe loss of ACTL7A expression. The loss of both ARPs also disrupted nuclear lysine acetylation and the intranuclear import of HDAC1 and HDAC3, critical regulators of gene repression and activation in the male germline. Lastly, this body of work employed and validated the accuracy of in silico models predicting ARP interactions with Helicase-SANT���associated (HSA) domains, uncovering further roles of ACTL7A and ACTL7B in nucleosome remodeling complexes. Both ARPs were found capable of binding to INO80 and SWI/SNF nucleosome remodelers, akin to nuclear actin and ACTL6A binding, implying potential germline-specific roles of these nucleosome remodelers. Ultimately, these studies delineate the multifaceted roles of ACTL7A and ACTL7B proving their indispensability for male fertility
Phantom Telemetry: Dynamics of Power and Transformation Beyond Earth
No full textThis creative project is a SF novel in a Victorian-era inspired world, exploring how the portrayal of the Other can be utilized as a representation of the alienation that comes with recognizing the power structures that run your life. The novel focuses on the viewpoint of a married woman named Octavia who travels to the planet Aneris, which has been colonized by humans who learned to bond with the insectoid symbiotes native to the area; as she tries to assimilate to the culture of Aneris, she is also attempting to investigate why her father was exiled from the planet in the first place. Throughout the book, Octavia struggles to reconcile her societal role as a married woman with her desire to pursue the mysteries of the symbiotes. The creative work uses the symbiote as a symbol of the Other in the sense of a metaphysical unknown, paralleled with Octavia���s status as the Other due to her marginalization. Theoretical lenses used in the construction of this creative artifact include Darko Suvin���s theory of cognitive estrangement and Edward Said���s theory of postcolonialism, and the novel employs the dual vision often seen in marginalized perspectives of the world to capture Octavia���s perspective
Calibration Measurements of Two Scientific Grade Astronomical Cameras
Get PDFWe present the results of a calibration analysis of two scientific grade cameras: a SBIG ST-8300 CCD and a APOGEE-ALTA F16M CCD. Sets of bias frames, dark frames, and flat fields were taken with both detectors. Analysis of images using Python suggests the two cameras are overall within design specifications. Calculations produce a gain factor, read noise, and dark current of 0.407 electrons/ADU, 53.9 ADU, and .0222 electrons/s for the SBIG detector and 1.58 electrons/ADU, 28.1 ADU, and .0805 electrons/s for the APOGEE detector. Inspections of linearity curves for both detectors reveal slight nonlinear responses, potentially requiring further investigation and future testing. Additionally, observations of Landolt standard star field SA101 were conducted with both cameras to determine the photometric zero point and a typical color term, providing a zero point of 4.686 for the SBIG ST-8300 and inconclusive results for the APOGEE-ALTA F16M. With the eventual completion of this work, these cameras may be used as part of future scientific equipment built by the Munnerlyn Instrumentation Lab
