Showing 2231 - 2240 of 5708 Items
Creating Enantioselective Peptoid Catalysts with 2-Picolylamine and 2-Picolinic Acid Catalytic Sites Access to this record is restricted to members of the Bowdoin community. Log in here to view.
Date: 2024-01-01
Creator: Devin Kathleen O’Loughlin
Access: Access restricted to the Bowdoin Community
Bamboo Corals as Climate Archives: Radiocarbon-based Chronologies and Evaluation of Mg/Li as a Temperature Proxy Access to this record is restricted to members of the Bowdoin community. Log in here to view.
Date: 2016-05-01
Creator: Megan M Freiberger
Access: Access restricted to the Bowdoin Community
Physiological responses of the American lobster cardiovascular system to neuropeptide SGRNFLRFamide (SGRN)
Date: 2024-01-01
Creator: Andre Eden
Access: Open access
- During every second of a human’s life, the cardiovascular system is modulated by factors both intrinsic and extrinsic to the physiology of the heart. We can uncover new insights regarding the nature of our system through investigations of similar systems in other model species. One example materializes itself in the form of the American Lobster (Homarus americanus) whose single-chambered heart finds resemblance to the function and anatomy to that of humans. The lobster heart is powered by the cardiac ganglion (CG), a group of neurons that drive contractions of surrounding heart muscles, known as the myocardium. Both the CG and myocardium work in a feedback loop, with both intrinsic (afterload and preload) and extrinsic (temperature and neuropeptides) factors affecting cardiac output (CO) or the overall ability of the heart to carry out its primary function of nutrient distribution. In this paper, we examine how the addition of these factors into in vitro whole heart preparations affect CO and other associated variables. From experimentation, we conclude that the neuropeptide SGRNFLRFamide (SGRN) increases the heartbeat frequency and the active force exerted by the heart. We also conclude that increases in temperature decrease CO as higher temperatures decrease heartbeat frequency and the active force exerted by the heart. Lastly, we conclude that the effect of preload and afterload combined produce more robust effects on the CO and active force of the heart, potentially painting a better picture of what may happen in vivo.
Mitigation of Negative Effects of Ocean Change on Oysters by Eelgrass and its Implications for Aquaculture in Midcoast Maine
Date: 2022-01-01
Creator: Fiona G Ralph
Access: Open access
- Species interactions are important to organisms and to the ecosystems they inhabit. These interactions, sometimes facilitations, can result in increased resiliency for both species. When facilitation occurs, organisms co-assist with physiological and environmental stressors. As anthropogenic impacts become more stressful for modern organisms, these interactions could offer a solution for many species. Ocean acidification has been shown to be detrimental to many calcifying organisms including oysters. More acidic conditions can slow the process of shell calcification, which can slow growth rates. This effect could directly impact the robust oyster farming business in Midcoast Maine. Because of its possible importance to oyster crops, we assessed the potential of Zostera marina, or eelgrass, to ameliorate the stresses of ocean acidification on farmed Eastern Oysters (Crassotrea virginica). Photosynthesizing organisms such as seagrasses have been shown to locally raise pH, which could create growth refugia for calcifying organisms. While eelgrass has the potential to enhance oyster growth rates, its meadows could also be influencing food availability. To better understand these dynamics, we grew C. virginica in two locations in Harpswell, ME. Crassostrea virginica were split into three habitats at each location: seagrass, fringe, and mudflat, and placed on surface or benthic arrays. We found that seagrass presence and depth interacted to increase shell growth rate. Similarly, Z. marina improved condition index of C. virginica. As ocean acidification worsens, oyster farmers might have to turn to mitigation strategies to ensure profit yield from their labors. Zostera marina could be the solution to their future problems.
A Time for Every Purpose: Race, Medical Professionalism, and the Physicians’ Dilemma
Date: 2022-01-01
Creator: Reuben Mindlin Schafir
Access: Open access
- This thesis examines the intersection of race and professionalism in healthcare as they relate specifically to the debate over universal healthcare. It begins with the National Medical Association (NMA), a professional organization for Black physicians founded in 1895. The first two chapters follow the NMA as they attempt to navigate the two allegiances they have: one to be "race men," and work for racial equity in healthcare, and one to be professionals, and work towards affirming their professional sovereignty. The narrative begins in 1945, when President Harry Truman backed the first substantial proposal for a system of nationalized healthcare. Chapter two discusses the 1960s and how the confluence of the Great Society and the civil rights movement provided Black doctors with an opportunity to successfully serve both aspects of their identities. The third chapters explores the 1970s and the events following the passage of Medicare and Medicaid. The NMA began to align itself more closely with the American Medical Association (AMA), which had long-embodied the medical establishment. When this alignment occurred, the Black Panther party offered an alternative method of addressing racial health inequities that rejected not only the notion of healthcare as a commodity, but the entire national identity associated with the free market within which physicians sold care. This thesis considers how the interests of patients and the interests of doctors do and do not align, using race to bring this tension into high relief.
Binding Energy Determination of CO2 Adsorption in MOF-74 with Diffusion Monte Carlo This record is embargoed.
- Embargo End Date: 2027-05-19
Date: 2022-01-01
Creator: Yucheng Hua
Access: Embargoed
Music and Autism: Cross-Disciplinary Dialogues Access to this record is restricted to members of the Bowdoin community. Log in here to view.
Date: 2021-01-01
Creator: Daniel Rohan Mayer
Access: Access restricted to the Bowdoin Community