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Spill the Tea
No full textRococo woman sipping the tea with big eyes as she listens to what seems to be a juicy gossip. She is the listener
Effects of ocean warming and acidification on the rates of suspension feeding for two reef invertebrates in the northern Gulf of Mexico
No full textOcean acidification and warming often have species-specific consequences on organismal behavior and physiology that in turn can scale to influence ecosystem processes. Suspension-feeding invertebrates couple benthic and pelagic processes and are prominent taxa at artificial reefs throughout the northern Gulf of Mexico (nGoM) - a region where effects of global ocean change are relatively understudied. Our purpose was to evaluate whether predicted ocean changes will impact the feeding rates of two suspension-feeding invertebrates abundant on nGoM reefs, the Leafy jewel box clam (Chama macerophylla) and Titan acorn barnacle (Megabalanus coccopoma). In a laboratory mesocosm, organisms were exposed to single- and multi-stressor treatments. Treatments mimicked current conditions as well as modest and extreme scenarios of warming and acidification predicted for the end of the 21st century. Feeding rates were measured within isolated chambers. Organisms were fed algae and the remaining algae were assessed at set time intervals (5, 20, 40, and 80 minutes) using images slides, analyzed with image-J. Bivalve feeding appeared unaffected yet, barnacles kept at the more extreme acidification scenario (corresponding to pHT of 7.5) had significantly increased feeding rates (p \u3c 0.001) compared to other conditions(pHT of 8.1 and 7.8). This effect, however, was not observed in multi-stressor treatments. Therefore, barnacles may only be able to compensate for moderate stress by taking up more energy. This interpretation is consistent with survivorship measured in the same study and is concerning given suspension feeders improve water clarity and serve to transfer primary productivity from the water column into secondary fish production
Photocatalytic Degradation of Organic Dyes using TiO2@Hexaniobate Nanopeapod
No full textTitanium dioxide (TiO2) nanoparticles (NPs) and hexaniobate (HNB) nanoscrolls (NScs) are both well-known photocatalysts. The combination of TiO2 NPs with HNB NScs, in the form of TiO2@HNB nanopeapods (NPPs), leads to a new nanocomposite material with enhanced photocatalytic activity. Solvothermal processing is effective in the synthesis of TiO2@HNB NPPs where TiO2 NPs and surfactant are combined with dispersed HNB nanosheets to achieve the NPP composite structure. Surface modification of the NPPs, for greater dispersibility in an aqueous medium, can then be carried via methylation. The NPP morphology where NPs are encapsulated in NScs was confirmed by transmission electron microscopy (TEM). Photocatalytic activity of the NPPs was investigated through the degradation of different dyes (methylene blue, brilliant green, and rhodamine B) under an in-house 460 nm LED reactor. UV-Vis spectroscopy was used to monitor the disappearance of the dyes. Dye degradation was found to be significantly faster in the presence of TiO2@HNB nanopeapods than with either TiO2 NPs or HNB nanoscrolls
Ammonia for Renewable Energy Storage: Novel Heterogeneous Catalysts for NH3 Decomposition
No full textTo enable widespread usage of renewable energy, which is generated both intermittently and distant from its point of use, energy must be stored either in a battery or as a fuel. Hydrogen is difficult to store and transfer due to its low density. In contrast, ammonia can be liquefied at 9.2 bar pressure at room temperature. Ammonia has a very high, 17.6%, hydrogen content. The most efficient catalyst for NH decomposition, ruthenium (Ru) metal, is expensive. A series of mixed metal oxides with perovskite structure, e. g. LaCrO , LaMnO , LaFeO , LaCoO , and LaNiO , were studied as catalysts for ammonia decomposition. The results indicate that they are all either reduced to metal or transformed to metal nitride and lanthanum oxide. This study shows that perovskites have negligible activity toward ammonia decomposition reaction. However, after the reduction in ammonia, they are transformed into highly active catalysts. We have discovered that cobalt metal on lanthanum oxide (La2O3) support demonstrates 4 times higher activity at 450°C than on other supports. In our study, the activity of new heterogeneous catalysts for ammonia decomposition (cobalt and nickel alloys on lanthanum oxide support) was determined in the range of temperatures using a fixed bed flow reactor. Co Ni with x = 0.05 is five-times more active than pure cobalt at 400°C. The low cost and, potentially, the high catalytic activity of these alloys will enable cost-effective NH3 to H2 conversion
Archaeology and Descendant Communities: A Case Study of St. Rosalie Plantation (16PL107)
Get PDFThe St. Rosalie Plantation (16PL107) is an Antebellum-era sugar plantation site located on the western bank of the Mississippi River in Plaquemines Parish, Louisiana. From 2019-2020, an environmental and cultural resources company conducted a Phase II investigation of the site to determine its NRHP eligibility and uncover the locations of cemeteries known to exist on site. Their determinations made from the fieldwork and artifacts fell short of the reality that existed underneath the surface. With my reanalysis of this project’s artifact inventory, I hoped to reveal what I believe is actually represented through the assemblage and what this could mean for the site. An examination of problems associated with CRM/archaeological practices involving descendant communities is also discussed, the project serves as a prime example of why archaeologists need to focus on the social impacts of their work. St. Rosalie holds information pertaining to post-Emancipation communities at the site, and nearby descendant communities should be involved in every aspect of archaeological research in order to gain knowledge of their ancestors and heritage
Community in the Cell: Queer Women’s Space and Place in New Orleans
Get PDFThis thesis examines queer women’s history and space/places of community in New Orleans using spatial analysis and feminist theory to fill the silences. The Special Citizens Committee for the Vieux Carré laid the foundation for regulating queer women and transmasculine people starting in the 1950s. Even after the committee ended, New Orleans Police Department and the Vice Squad had the power to invade and harass places of community for queer women and transmasculine people. Despite this hostility, queer women and transmasculine people resisted and made a place for themselves in New Orleans. As a result of their persistence through visibility in New Orleans, many queer women and transmasculine people shared the experience of being arrested and placed in jail. This paper aims to show that queer women\u27s resistance continued into the various spaces of incarceration in New Orleans
Childcare Organizations: A Qualitative Study on Childcare Leaders’ Perceptions of the Elements that Promote the Work They Do in the Childcare Industry
Get PDFResearch has often highlighted the positive effects of high-quality early care and education on children\u27s development and the economy. However, the challenge of ensuring access to quality care for all children and understanding the perspectives of leaders doing crucial work on the ground remains. Given the strong associations between high-quality early childhood education, brain development, and positive economic outcomes for those who access high-quality care, my paper introduces a theory of change. This theory outlines a pathway from understanding the determinants of quality in childcare centers, as seen through the eyes of industry leaders, to the implementation of policy changes. I focus on how leaders within the industry describe themselves, their centers, the world, and their values. The evidence presented in this paper showcases strategies that leaders employ to uphold their status as pioneers in early childhood education