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Oyster allometry: growth relationships vary across space
No full textOysters have unique life history strategies among molluscs and a long history in the fossil record. The Ostreid form, particularly species from the genus Crassostrea, facilitated the invasion into intertidal, estuarine habitats and reef formation. While there is general acknowledgement that oysters have highly variable growth, few studies have quantified variability in oyster allometry. This project aimed to (1) describe the proportional carbonate contributions from each valve and (2) examine length–weight relationships for shell and tissue across an estuarine gradient. We collected 1122 C. virginica from 48 reefs in eight tributaries and the main stem of the Virginia portion of the Chesapeake Bay. On average, the left valve was responsible for 56% of the total weight of the shell, which was relatively consistent across a size range (24.9–172 mm). Nonlinear mixed-effects models for oyster length–weight relationships suggest oysters exhibit allometric growth (b < 3) and substantial inter-reef variation, where upriver reefs in some tributaries appear to produce less shell and tissue biomass on average for a given size. We posit this variability may be due to differences in local conditions, particularly salinity, turbidity, and reef density. Allometric growth maximizes shell production and surface area for oyster settlement, both of which contribute to maintaining the underlying reef structure. Rapid growth and intraspecific plasticity in shell morphology enabled oysters to invade and establish reefs as estuaries moved in concert with changes in sea level over evolutionary time.Virginia Institute of Marine Scienc
Ecological Monitoring Program at VIMS ESL: Annual Report 2023
No full textAn Ecological Monitoring Program (EMP) has been established at the Virginia Institute of Marine Science Eastern Shore Laboratory (VIMS ESL) for the coastal environment near the Wachapreague lab. The goals of the initiative are to 1) provide status and trends information to scientists who study and regulators who manage Virginia’s marine resources, 2) provide a scientific context for short-term research and grant proposals 3) provide pedagogical enrichment for educators to use in their classes, and 4) build capacity in staff expertise and training of interns and students at VIMS ESL. The program formalizes and standardizes data collection for a long-term status and trends database as an asset of VIMS ESL in addition to our marine operations and shore support facilities. The EMP standard methods also provide visiting scientists and educators with protocols for consistent and comparable work and training. The EMP includes electronic water quality stations, oyster settlement and adult population dynamics, microbial biofilm growth, characterization of benthic communities in soft sediments and oyster reefs, sediment characteristics, and drone surveillance of salt marsh die back, Wachapreague Inlet dynamics and macroalgae distribution on mudflats. While this document focuses on these core areas of our monitoring activities, results of other VIMS ESL research on shellfish aquaculture, bay scallop restoration, and shorter-term grant supported research projects are reported elsewhere.Virginia Institute of Marine Scienc
Bats And Rockreation: Is Recreation A Vector Of Pseudogymnoascus Destructans At Devils Tower National Monument?
No full textWhite-nose syndrome (WNS) is a disease that causes mass mortality in North American hibernating bat species due to infection by a fungal pathogen, Pseudogymnoascus destructans (Pd). Subterranean recreation has been linked to the spread of WNS, but research has yet to assess if aboveground recreation (e.g., rock climbing or scrambling) influences transmission. Two bats were diagnosed with WNS in 2021 during WNS surveillance efforts at Devils Tower National Monument (DTNM), Wyoming, a popular outdoor recreation destination. Our objectives for this research were to: 1) assess presence and 2) seasonal variation of Pd in the environment at DTNM; 3) analyze relationships between bat and human use of rocky features at DTNM; and 4) determine if rock climbing or scrambling contribute to the spread of Pd. Environmental samples were collected and tested for the presence of Pd via PCR from climbing routes, the boulder field surrounding the Tower, and sandstone outcrops approximately half a mile from the foot of the Tower during 2022 (Spring N=122; Fall N=360 ) and 2023 (Spring N=505; Fall N=181). One boulder field site tested positive for Pd in both spring and fall of 2023. However, Pd was not present in detectable amounts in all other field samples. When Pd was placed on items (N=785) commonly used for aboveground outdoor recreation (e.g., shoes, ropes, specialized climbing protection) and exposed to environmental conditions typically experienced at DTNM (temperature and direct light), the fungus could persist and be viable, though this decreased over 16-hours of continuous exposure. Further, Pd spores can be transferred from one surface to another. We conclude that aboveground recreation has the capacity to carry and transfer Pd spores, but further research is still needed to assess the degree to which outdoor recreationists are initially exposed before considering wildlife protection and outdoor recreation plans.BiologyMaster of Science (M.Sc.
Significance of lysine acetylation in response regulator ArsR of Helicobacter pylori
No full textHelicobacter pylori is a gram-negative spiral-shaped bacterium that infects the gastric epithelium and can subsequently cause gastric carcinoma and peptic ulcer disease. H. pylori can survive and colonize the harsh environment of the stomach by utilizing an acid-sensing and response mechanism, the ArsRS two-component system (TCS). The histidine kinase ArsS auto-phosphorylates when exposed to an acidic pH. ArsS then phosphorylates the OmpR-related response regulator, ArsR, which when phosphorylated acts as a transcriptional regulator for a variety of genes. Prior research has shown that ArsR is an essential protein for H. pylori survival, as ΔarsR strains are not viable in the laboratory. A growing body of evidence has also shown that lysine acetylation at highly conserved lysine residues K87, K101, and K202 in OmpR-related response regulators modulates their function. This information led us to hypothesize that highly conserved lysine residues of ArsR are acetylated, affecting expression of ArsR-regulated genes. To test our hypothesis of lysine acetylation in ArsR, we conducted mass spectrometry of the ArsR-FLAG protein which confirmed the presence of lysine acetylation at lysine residue K87 in ArsR. To determine the effects of this acetylated lysine residue in ArsR, we created acetyl-mimic mutants for each of the three conserved lysine residues and quantified mRNA levels of a well-characterized ArsR up related gene, ureA at pH 7 and pH 5. We found that the mutation of these lysine residues results in an inability for ArsR to differentially regulate ureA in K87 and K101 residues in comparison to our control mutant 26695 in response to acidic conditions. Our findings along with the growing body of evidence regarding lysine acetylation in prokaryotes shows not only the evolutionary conservation of this modification but emphasizes the functional diversity prokaryotes utilize for complex cellular functions.BiologyBachelors of Science (BS
The Body in Pieces: Towards a Feminist Phenomenology of Violence
No full textThis article proposes that feminist phenomenology offers an essential set of conceptual tools for analysing forms of violence which destroy the body beyond the point of death. To illustrate the potential utility of this approach, I apply this lens to the 11 September 2001 attack on the World Trade Center in Manhattan, New York City. I identify several distinct modes of bodily transformation from the attack, grouped into three broad categories: vaporised bodies, intermingled remains, and hidden fragments. I describe how these transformations unsettled the relationships between bodies and contexts, and occasioned the formation of new relationships in ways that heightened and extended the violence of the attack. I end with a discussion of attempts to resettle and repair these relationships through the creation of fictive bodies. These fictive bodies aim to repair the specific harms caused by the derangement of bodily relations by re-establishing firm boundaries between heroic, national bodies, and the monstrous body of the attacker. Through rigorous engagement with this case, I illustrate the unique potential of feminist phenomenology to account for the relationships between bodies, objects, and spaces as the site of political meaning-making in the aftermath of violence.Governmen
From The Ground Up: Practical Gardens And Horticultural Knowledge In Early America
No full text“From the Ground Up: Practical Gardens and Horticultural Knowledge in Early America” argues that practical gardens and horticultural knowledge were important features of ordinary early Americans’ intellectual lives in the eighteenth and early nineteenth centuries. It reveals the intricacies of practical garden-keeping in New England and the Mid-Atlantic region, showing not only how horticultural knowledge was made by individuals and in households, but also how knowledge moved between households and into crystallizing scientific societies and texts during this period. Practical gardens contained produce to be consumed by the household, as sustenance, seasoning, or medicine. From grafting bits of fruit trees together to create an entirely new breed, to recording the effects of heavy rainfall or drought on one’s plants, to experimenting with fertilizer recipes, to sharing seeds and trading labors with neighbors, these gardens were manifestations of gardeners’ intense collaborative kinetic and intellectual work. “From the Ground Up” examines horticultural knowledge-labors from a variety of perspectives, pulling together a constellation of micro-experiences, tasks, and knowledges of gardens and gardening. Focusing on one household garden, it first examines how labors and knowledges combined within, and how gardeners’ statuses influenced their horticultural roles. It then shows how gardeners recorded their successes and struggles in the margins and interleaved pages of their almanacs. Almanacs’ form and content advised and facilitated the annotations within. Gardeners’ knowledge also moved beyond the bounds of their gardens and almanacs. Through exchanges of garden seeds, cuttings, and labors with neighbors, horticultural knowledge circulated in local communities. Finally, “From the Ground Up” demonstrates that as traveling naturalists observed practical gardens and learned from ordinary gardeners, gardeners’ horticultural knowledge and networks of horticultural circulation became the basis for emerging scientific canons and societies. In many ways, ordinary people’s horticultural knowledge and its circulation shaped the intellectual and physical landscapes of early America and beyond.HistoryDoctor of Philosophy (Ph.D.
Onboarding Campus-Based Sorority and Fraternity Professionals in Remote Work Environments
No full textThe COVID-19 pandemic presented challenges to offering robust onboarding experiences for new campus-based sorority and fraternity professionals. As higher education institutions continue to emerge from the pandemic, supervisors and professional associations should be concerned by what new professionals’ onboarding experiences means for ongoing supervision, professional development, and longevity in the field. This research provides insight into how new campus-based sorority and fraternity professionals and supervisors navigated early remote onboarding experiences. The findings illuminate a need to better understand supervisory relationships, communication styles, and socialization processes impact the perceptions of newcomers and how intentionality of supervisors can help mitigate anxiety and uncertainty of adjusting to a new role
Phytoplankton Biogeography: Where is My Home?
No full textGrades: 9-12. Subjects: Life Science | Biology | Environmental Science | Oceanography Conceptualizing the basics of biogeography through the generation, visualization, and interpretation of a phytoplankton dataset.Virginia Institute of Marine Scienc
Moving Pictures: Reassessing Art Outreach Exhibitions In The United States, 1900-1960
No full textThis dissertation examines art outreach exhibitions active in the United States between 1900 and 1960. I define outreach exhibitions as shows organized by museums, galleries, and other arts-focused organizations for schools, libraries, and other non-gallery spaces, to expand audiences. Despite their longevity as a community engagement method, outreach exhibitions have received limited critical attention from scholars or museum personnel, with museums historically relying on quantitative measures such as total visitor attendance or number of sites visited to ascertain effectiveness. By assessing outreach exhibitions as a historical form of collections engagement, my research examines how museums, galleries, and art centers have historically attempted to cultivate community relationships through collections access. I begin by examination of outreach exhibitions by tracing their origins to Progressive Era activism in public education, with art museums physically dispatching their collections to demonstrate the commitment to public service. I then analyze three case studies active from the Great Depression through the Cold War: the Metropolitan Museum of Art’s Neighborhood Circulating Exhibitions, active from 1933 to 1942; the federal community art center (CAC) initiative, one of the most ambitious arts access initiatives associated with the New Deal; and the Virginia Museum of Fine Arts’ Artmobile, active from 1953 to 1994 and revived in 2018. To analyze these case studies, I use an interdisciplinary method intersecting history, mobility studies, and archival theory. For each outreach program, I analyze their content, retrace their transit routes, identify which kinds of community organizations or host sites they engaged, and examine the tensions that arose between the organizers of outreach exhibitions and their hosting sites and community members. I also consider audience reactions to outreach exhibitions to complicate quantitative assessments of success and demonstrate that viewers were not monolithic regarding their familiarity with art or their expectations of the programs that visited them. I argue that outreach exhibitions active during the first half of the twentieth century, though intended to expand access to collections, reproduced the boundaries of their host institutions by replicating operations and expectations that first developed out of Progressive Era reforms. They did so by privileging collections preservation, focusing on schools and other public education sites to demonstrate educational relevance, envisioning their audiences as people who already supported or would support the conventions of museums, and privileging whiteness in their exhibition contents, institutional partners, visitation sites, and imagined audiences. Outreach exhibitions demonstrate how a lack of institutional self-awareness results in the uncritical replication of established museum practices and expectations.American StudiesDoctor of Philosophy (Ph.D.
“I’m Not Your Mom, I’m Your Sister”: A Normative Approach to Understand How National Panhellenic Council Sorority Leaders Handle Honest Conversations
No full textThis study used Goldsmith’s normative rhetorical theory to explore dilemmas in honest conversations between National Panhellenic Council (NPC) sorority members. Researchers interviewed 16 leaders from one NPC sorority across 14 chapters in the United States. A phronetic iterative analytic approach revealed two communication dilemmas: I have to have this honest conversation with you, but I do not want to and I have power, but I am your equal. To manage these dilemmas, two communicative strategies were identified: intentional planning and message delivery. Findings offer guidance on navigating honest conversations to foster belonging and maintaining a supportive social network