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Coaching First-Grade Teachers On Differentiated Instructional Practices For Learners With Mathematical Promise: An Action Research Study
No full textThis action research study in a North Dakota public school addresses the need for effective professional development (PD) to enhance instruction and academic outcomes for mathematically promising learners. Despite annual PD investments, concerns persist regarding the limited efficacy of short-term workshops (Knight & Skrtic, 2021; Kraft et al., 2018). Instructional coaching offers promise in implementing research-based instructional methods (Johnson, 2016). However, empirical support for coaching in differentiated instruction for high ability learners remains scarce. This study examined coaching’s impact on first-grade teachers’ differentiation practices for mathematically promising learners. It was selected as despite teachers’ awareness of differentiation benefits, many struggle with implementation, necessitating targeted support (Gavin, Casa, Firmender, and Carroll, 2013; VanTassel-Baska et al., 2020; Yuen et al., 2018). Through a mixed-methods approach, data were collected via teacher surveys and learner achievement growth scores to assess changes in differentiation practices, effects on learner performance, and influence on a teacher’s sense of efficacy. Results indicated noticeable shifts in teacher practice and increased sense of efficacy, despite a lack of improvement in learner achievement outcomes. Coaching positively influenced teacher perceptions and confidence surrounding differentiation practices, but improving academic performance for high ability learners remains complex. This dissertation contributes to instructional coaching and differentiation literature, highlighting coaching’s potential to support educators in serving mathematically promising learners and informing the development of more effective PD initiatives.EducationDoctor of Education (Ed.D.
Biogeochemical Controls On Dissolved Organic Matter Reactivity In Surface Waters And Tidal Marsh Porewaters Along A Temperate Estuary
No full textEstuaries and tidal wetlands are among the most ecologically and economically important ecosystems on Earth. They are well-known for their roles in supporting biodiversity, providing habitats for commercially important fisheries, and protecting shorelines from storms and wave action. These ecosystems are also important components of the coastal carbon cycle due to their role in carbon processing and export. However, these functions are threatened by warming temperatures, landscape alteration, eutrophication, sea level rise, and altered weather patterns. Dissolved organic carbon (DOC) is the least characterized carbon pool but plays a critical role in the aquatic food web as the foundation of the microbial loop. However, characterizing the sources, composition, and fate of DOC is challenging due to its heterogeneity and dynamic behavior in the environment. To better understand DOC dynamics in estuaries and tidal wetlands, this dissertation examined the environmental controls on microbial DOC production and decomposition within surface waters and marsh porewaters along the York River Estuary (YRE), a temperate sub-estuary of the Chesapeake Bay in southeast Virginia, USA. Seasonal field campaigns and laboratory manipulation and incubation experiments of estuarine surface waters and tidal marsh porewaters were conducted under dark (and anoxic for porewater incubations) conditions. Environmental and biogeochemical conditions were also assessed for the estuarine (hydrology, DOC source and composition, nutrients) and tidal marsh (DOC source and composition, nutrients, soil characteristics, microbial communities) study systems. Along the YRE, surface water DOC reactivity was higher during low discharge periods when autochthonous, aquatic sources of DOC dominated. In comparison, DOC reactivity was lower when more allochthonous, terrestrial sources of DOC were more abundant during high discharge periods when precipitation in the Chesapeake Bay region was anomalously high. In tidal marshes along the YRE, spatial variation in salinity and porewater characteristics were related to differences in soil microbial communities primarily involved in methane, nitrogen, and sulfur cycling. These metabolic functions differed in magnitude but co-occurred regardless of location along the estuary, indicating that microbial metabolic processes were not limited based strictly on salinity and biogeochemical gradients. Results from marsh porewater incubations showed complex patterns in DOC loss and production. DOC loss coincided with time periods when labile DOC was more prevalent and sulfate reducers and nitrate-reducing taxa comprised a large proportion of the active microbial community. DOC production, potentially through chemolithoautotrophy, coincided with time periods when refractory CDOM was more prevalent and sulfide oxidizers comprised a large proportion of the active microbial community. Overall, this dissertation shows that DOC composition, hydrology, and microbial community dynamics are primary, interacting controls on the biological fate of DOC in estuaries and tidal marsh porewaters. Human activities and climate change will have profound impacts on the coastal carbon cycle by shifting the forms, magnitude, composition, and reactivity of DOC in estuaries and tidal wetlands. By considering the importance of these controls under a variety of environmental conditions, these results help to better characterize the role of DOC in the coastal carbon cycle as the biogeochemical functions of coastal ecosystems respond to future change.Virginia Institute of Marine ScienceDoctor of Philosophy (Ph.D.
International Education’s Academic Benefit: Potential for Community College Virtual International Exchange
No full textThis study focuses on the potential academic benefit of virtual international exchange for community colleges and the students they enroll through a comparison of virtual exchange and study abroad. Using data from two community colleges in the US Southeast, this study draws upon the notion of socioacademic integration. Specifically, this study theorizes that both virtual exchange and study abroad have a positive relationship with students’ academic outcomes given their potential to foster socioacademic integrative moments. How- ever, given the scalability of virtual international exchange, it was expected that these programs are associated with a greater relationship to students’ academic outcomes in the aggregate. This study’s results generally confirm these expectations, although findings for virtual exchange are less positive compared to study abroad. Results have implications for the establishment and success of both approaches to international education programming at community colleges. The potential for virtual international exchange to reach a larger group of students compared to study abroad, thus having a greater aggregate impact on students’ success and outcomes, has key policy implications particularly for community colleges, for which service to the community is an integral component of institutional mission.Educatio
Personality Pathways: Depression and Nonsuicidal Self-injury in College Students
No full textNonsuicidal self-injury (NSSI) is a prevalent form of behavioral dysregulation among adolescent populations, specifically those with depressive symptoms. This paper expands the study of NSSI and personality variables by testing a moderated-mediation model in which cognitive reappraisal and expressive suppression act as mediators within the relationship between depressive symptoms and NSSI and five impulsivity-like traits act as moderators of the link between depression and emotion regulation. Participants (n = 1,847) were college students from 5 universities across the United States, mostly female (60.5%), white (66.2%), and with a mean age of 19.57 (SD = 2.79). The analytic sample included those who responded yes/no to past-year NSSI, while the subsample consisted of those who endorsed one or more methods of NSSI in that time frame. Analyses were conducted via Hayes’ PROCESS v4.0 for SPSS. Within our models, depression showed significant direct effects on both NSSI engagement and NSSI severity, though emotion regulation factors did not significantly mediate these relationships. Exploratory mediation models for impulsivity-like traits revealed that negative urgency emerged as a key mediator in the link between depression and both NSSI engagement and severity. Within the subsample, positive urgency was also a significant mediator, such that positive urgency partly explains the link between higher depression and greater NSSI severity. These outcomes elucidate the relationships between impulsivity-like traits, emotion regulation, and self-injury. Findings suggest potential for preventative work in the clinical treatment of depression as it relates to NSSI.PsychologyBachelors of Arts (BA
Acetone Metabolism and the Acetone Carboxylase Operon in Helicobacter pylori
No full textHelicobacter pylori is a gram-negative pathogenic bacterium that infects the human stomach and is the leading cause of peptic ulcers and gastric cancer. This infection requires utilisation of two component systems to sense and respond to changes in the environment. Our lab established a novel regulon controlled by the CrdRS two component system (Allen, Bate, et al., 2023). Of these novel genes identified, we chose acxA to research further. acxA is part of the operon acxABC encoding the subunits of the enzyme acetone carboxylase which converts acetone into acetoacetate which is eventually converted to acetyl-coA for entry into the TCA cycle. The operon acxABC therefore may be essential for acetone metabolism and generating energy for H. pylori. Acetone, a ketone body, may be present in the human stomach especially during starvation conditions. Due to the ancient association between H. pylori and the human stomach, and the frequency of starvation during human evolution, we speculate that the ability of H. pylori to metabolize acetone as a source of carbon provided an advantage to the survival of this bacterium. We analysed the distribution of this operon across Helicobacter species using BLASTP and found acetone carboxylases to be mostly present in gastric species and less prevalent within enterohepatic species suggesting acetone metabolism may be adaptive in the gastric niche. The extensive regulation of acxA and increased colonization of murine stomachs due to acetone carboxylase, all documented in the literature, suggests the critical importance of acetone carboxylase to H. pylori. We evaluated the effect of nitric oxide (NO) on acxA mRNA expression and using RT-qPCR on H. pylori 26695 CrdR D53A and CrdS H173A phospho-incompetent mutants, we demonstrated that acxA mRNA expression is decreased by NO in a CrdRS dependent fashion. We next investigated the effect of acetone on acxA mRNA expression using various concentrations of acetone. The limited increase in acxA mRNA expression led us to culturing H. pylori in F-12 medium, a defined, minimal medium. We then investigated the effect of acetone supplementation on the growth of H. pylori 26695 in F-12 medium. Our data suggests that H. pylori derives a growth advantage in the presence of acetone, perhaps as an alternative source of carbon. To delineate the role of acetone carboxylase in this growth advantage, we created a H. pylori 26695 ΔacxA mutant which had decreased growth compared to the control strain in the presence of acetone but no defect in growth in the absence of acetone. This suggests a crucial role for acetone carboxylase in H. pylori metabolism. Definition of key energy sources such as acetone for this gastric pathogen are critical to the study of H. pylori colonization and may aid in developing novel therapeutics.BiologyBachelors of Science (BS
Words Have Meaning, Choose Them Carefully: Language And The Obfuscation Of Women’s Contributions To American Warfare
No full textMore Than “Camp Followers”: Camp Women During the American Revolution, Their Value to Effective Warfare, and Historiographical Depreciation Women were essential to the Continental Army during the American Revolution and in the army’s eventual victory. They worked for the army as laundress, seamstresses, sutlers, and nurses. Largely, these women have been referred to as “camp followers.” However, the anachronistic use of that derogatory nineteenth-century term does not accurately portray their relationship with the army and instead does them a disservice. Their support of fighting men through various services was instrumental in supplying the troops and bolstering their efficiency. This paper explores the history of these remarkable women. Specifically, it delves into the motivations of this under-acknowledged group, their roles in supporting the American fighting forces, and how they came to be denigrated over time. It also investigates the distinctly nineteenth-century origins, uses, and implications of the term “camp follower” and how it was used to devalue and demean these women. Ultimately, it complicates and works to question the use of and redefine our understanding of the term itself. My analysis highlights the significant contributions these women made to the success of the Continental Army and, ultimately, the entire war effort. “White, Negro, Other:” The “Indian Princess” and Native American Woman in the Liminal Space of a Racially Segregated Military in World War II While Native Americans have the highest per capita rate of military service of any minority group in the United States, Native American women are one of the most understudied groups of service members. During World War II, their service in a segregated military was characterized by their existence in a liminal space that defied the binary the military tried to force them into. While they were classified as white, integrated into white units, and afforded opportunities exclusive to white women as a result, their individual experiences were reflective of their uniquely Indigenous identities and perspectives. This paper examines how Native American women experienced their indigeneity in the military during World War II. It especially explores how both the military and society at large tried to simultaneously erase and celebrate that Indigenous heritage by forcing them into a black-white binary while still utilizing highly racialized discourse to discuss their service. In the end, it complicates ideas of race in women’s military service branches during World War II, by highlighting that while the military itself only had white and black units, it had more than just white and black women and their experiences cannot be accurately reflected or explored within that binary.HistoryMaster of Arts (M.A.
"Let's Go, Ghouls!": Spiritualism And The Advancement Of Women Through Mediumship Within The United States
No full textA historical gender norm that has continued to undergird the gender system in the United States is that a woman is to be below a man in all matters. The two essays bound to this thesis dissect the relationship between U.S. American women and the Spiritualism movement that began in the mid-nineteenth century. This movement created opportunities for some who participated within it to become economically and socially independent. The first essay, “Spirituality Sold: How Women Took Advantage of Spiritualism Within the United States in the Nineteenth and Early Twentieth Centuries,” examines how women utilized their roles in the Spiritualism movement in order to garner economic success as well as a public presence when prescriptive norms dictated they were to be confined to their homes. For many within Western countries during this period, the ideal role for a respectable woman was (and unfortunately still is in some instances) to tend to her husband and his children. In my thesis I argue that Spiritualism, or the belief that humans could commune with the dead, was the “soul sister” to the women’s rights movement that emerged in nineteenth century U.S. America. Within Spiritualism, practitioners and mediums exalted femininity. Some women used their ability (or claim thereof) to talk to the spirits of deceased loved ones to make not only a name for themselves and carve a place within the economic sphere of the United States. The most well-known of these women were respected not only as renowned psychic mediums but also free thinkers and speakers on important social issues, earthly and other-worldly. Such women knew what they were doing with mediumship, and for that, they must be commended However, the belief that psychic mediums were and still are true, authentic communicators with the “other side” was fairly short-lived during and became a subject of critique and intense scrutiny with many (especially men) attempting to debunk these women’s practices and self-proclaimed abilities. The second essay, “From Spiritualists to Swindlers: The Contradictory Transformation of Support for Spiritualism and Female Psychic Mediums in the United States Beginning in the Twentieth Century,” interrogates the scientific technologies and psychological break-throughs that prompted many within the American spiritual counter public to increasingly doubt the veracity and authenticity of female psychic mediums. Drawing on examples from the first essay, the second portion of this thesis aims to examine why mediumship has been called into question since the nineteenth century and why, despite these notions of falsehoods amongst self-proclaimed “mediums” and “psychics,” many people then and today still choose to seek out psychic help. No matter if one were to view Spiritualism today or yesterday, one question raises itself into consideration for this particular body of research: why do people even seek out communing with the deceased and/or answering questions about themselves from others?American StudiesMaster of Arts (M.A.
Transcriptional Dynamics During Rhodococcus erythropolis Infection with Phage WC1
No full textBackground Belonging to the Actinobacteria phylum, members of the Rhodococcus genus thrive in soil, water, and even intracellularly. While most species are non-pathogenic, several cause respiratory disease in animals and, more rarely, in humans. Over 100 phages that infect Rhodococcus species have been isolated but despite their importance for Rhodococcus ecology and biotechnology applications, little is known regarding the molecular genetic interactions between phage and host during infection. To address this need, we report RNA-Seq analysis of a novel Rhodococcus erythopolis phage, WC1, analyzing both the phage and host transcriptome at various stages throughout the infection process. Results By five minutes post-infection WC1 showed upregulation of a CAS-4 family exonuclease, putative immunity repressor, an anti-restriction protein, while the host showed strong upregulation of DNA replication, SOS repair, and ribosomal protein genes. By 30 min post-infection, WC1 DNA synthesis genes were strongly upregulated while the host showed increased expression of transcriptional and translational machinery and downregulation of genes involved in carbon, energy, and lipid metabolism pathways. By 60 min WC1 strongly upregulated structural genes while the host showed a dramatic disruption of metal ion homeostasis. There was significant expression of both host and phage non-coding genes at all time points. While host gene expression declined over the course of infection, our results indicate that phage may exert more selective control, preserving the host’s regulatory mechanisms to create an environment conducive for virion production. Conclusions The Rhodococcus genus is well recognized for its ability to synthesize valuable compounds, particularly steroids, as well as its capacity to degrade a wide range of harmful environmental pollutants. A detailed understanding of these phage-host interactions and gene expression is not only essential for understanding the ecology of this important genus, but will also facilitate development of phage-mediated strategies for bioremediation as well as biocontrol in industrial processes and biomedical applications. Given the current lack of detailed global gene expression studies on any Rhodococcus species, our study addresses a pressing need to identify tools and genes, such as F6 and rpf, that can enhance the capacity of Rhodococcus species for bioremediation, biosynthesis and pathogen control.Data Scienc
The Ballad of a Thin Man: The Birth of Rock Criticism Through Bob Dylan and the Press
No full textBob Dylan is frequently included in conversations of the greatest artists of the 20th century, and yet his influence goes far beyond his music. In this thesis, I examine the question "How did Bob Dylan's relationship with the press from 1960 to 1966 help shape the practice of music journalism?" with a specific focus on how Dylan going electric helped legitimize rock music and rock criticism before the concept was solidified after 1967. Though Dylan is hailed as a great artist in his own right, his influence on rock criticism and his relationship with the press were significant contributions to the creation of the rock countercultural community in the 1960s.American StudiesBachelors of Arts (BA
Experimental Studies Of Neutral Particles And The Isotope Effect In The Edge Of Tokamak Plasmas
No full textThe H-mode plasma edge is a region of steep gradients in density and temperature known as the “pedestal” which greatly increases energy confinement. The complex links between neutral-plasma interactions and both diffusive and convective transport in the pedestal must be understood to model, predict, and achieve the high performance required for a fusion power plant. This dissertation explores the effects of different hydrogenic isotope neutral particles and plasma transport from the edge pedestal region into the Scrape-Off Layer. Current experiments typically use deuterium (H with amu=2 or D), however future fusion power plants may startup with hydrogen (H), and eventually burn a mixture of deuterium and tritium (H with amu=3 or T). As isotope mass increases, energy confinement also increases in direct contradiction to the predicted scaling from diffusive theory, a phenomenon known as the “isotope effect”. Using a database of H and D pedestals on the DIII-D tokamak, we show indications that both species pedestals are in electron-dominant turbulence regimes, where increased outwards convection for hydrogen contributes to lower electron density pedestals consistent with gyrokinetic theory. However, this is complicated by indications of fueling differences between the isotopes. To isolate the effect of fueling, we conducted an experiment on DIII-D to match electron density (ne) and temperature (Te) profiles between hydrogen and deuterium, where neutral particle ionization profiles were measured with the newly available Lyman-α LLAMA diagnostic. On the High Field Side (HFS), neutral penetration lengths (λn0 ) across the pedestal are 40% longer for hydrogen compared to deuterium, consistent with the thermal velocity ratio between the isotopes (v_{H_{th}}/v_{D_{th}} = √2), while measurements on the Low Field Side (LFS) suggest a transport effect. The influence of neutral penetration on electron density pedestal width (∆ne) diminishes with increasing opaqueness (η ≡ ∆ne /λn0 ), shown by low opaqueness pedestals (η ∼ 0.9) in hydrogen being ∼ 40% wider than their deuterium counterparts. Higher opaqueness η ∼ 2 more effectively shields the pedestal from neutrals, as indicated by hydrogen and deuterium having nearly identical ∆ne . Moving across the separatrix into the Scrape-Off Layer, we conducted a diagnostic validation exercise using the ELZAR analysis method with stereoscopic fast cameras on MAST to detect field-aligned turbulent transport events known as “filaments”. Comparisons between the cameras show similar data in individual frames, inversion maps, and statistical distributions of located blobs. The two most important parameters for the framework connecting the statistics to SOL steady-state profiles are the lognormal distributions for filament radial position and major axis width which are within error between the cameras. The remaining distributions are unimportant to the statistical framework and we systematically attribute their differences to the experiment setup.PhysicsDoctor of Philosophy (Ph.D.