Showing 5581 - 5590 of 5716 Items
Cosmological gravitational waves: Refining a general rule of thumb for reheating
Date: 2021-01-01
Creator: David Zhou
Access: Open access
- There are predictions for cosmological gravitational wave backgrounds from reheating based on various models. But, these predictions do not address the question of how an observed spectrum relates back to an unknown model or parameter. Given this problem, we have numerically and analytically investigated a variety of chaotic inflation models and their gravitational wave spectra. In doing so, we found a power law relation between gravitational wave peak frequency and an underlying chaotic inflation parameter. We found a two-class amplitude puzzle related to how strongly a matter producing field is coupled to the inflaton. We estimated the parameter describing how quadrupolar the gravitational wave source's energy density to good agreement with previous estimates.
Agent-Based Modeling of Asset Markets: A Study of Risks, Preferences, and Shocks This record is embargoed.
- Embargo End Date: 2026-05-18
Date: 2023-01-01
Creator: Evan Albers
Access: Embargoed
Service Beyond Bars: How Correctional Chaplains Mediate the Movement of Religion in Prisons and Jails This record is embargoed.
- Embargo End Date: 2028-05-18
Date: 2023-01-01
Creator: Lia F. Kornmehl
Access: Embargoed
"Proud Flesh and Blood": Phineas Fletcher, Gabriel Daniel, and Seventeenth-Century Theories of Embodiment
Date: 2022-01-01
Creator: Micaela Elanor Simeone
Access: Open access
- The human body was a site of discovery and redefinition in early modern Europe. This project traces the gradual arc from the mid-seventeenth century towards Cartesian notions of the body in the later part of the century through two fictions: Phineas Fletcher (1582-1650)’s The Purple Island (1633) and Gabriel Daniel (1649-1728)’s Voyage du Monde de Descartes (1690). This project views these two largely-overlooked texts as important literary works that represent the seventeenth century’s transformative debates about and explorations of the human body. I argue that Fletcher employs a dissective mode that embraces mind-body harmony while framing the human as both fragmented and whole. I then explore how Voyage du Monde de Descartes responds to an altogether different culture in the late seventeenth century, after Cartesian ideas extracted mind from body and no longer saw the body as a significant marker of humanity. I argue that Voyage ultimately reveals—through a captivating satirical fiction—how understanding Cartesian anatomy as the product of anxiety, uncertainty, and novelty helps us better see how we became motivated to transcend our bodies.
Searle’s Mind: Brains, Subjects, and Systems
Date: 2023-01-01
Creator: Saul Cuevas-Landeros
Access: Open access
- Throughout this project, I ‘step into the Chinese Room’ presented by philosopher John R. Searle and develop the areas where the Chinese Room Argument succeeds. I have aimed to pick out where Searle has succeeded with the Chinese Room Argument and introduce how it fits in with his school of biological naturalism, as it seems that he already had some conception of it when presenting the Argument. From here, I introduce some of the primary arguments against the Chinese Room Argument because they do not fit with Searle’s overarching theme of biological naturalism. Particularly, Searle’s conception of systems and system features is something he endorses for the biological but immediately labels as silly for the Chinese Room. Following the exposition of systems and system features, I expand on how there is a disconnect between Searle’s use of system features and his view of the Chinese Room Argument. What is so special about Searle’s conception of systems and the systems present in the Chinese Room Argument? Searle should claim that the Chinese Room is simply not the kind of thing that can think. Ultimately, Searle’s philosophy of mind leaves us with either a muddled philosophy or an invalid argument in the Chinese Room, but with much to learn and not forget to consider in the philosophy of mind, such as the important role of subjectivity in our conscious life.
Impacts of eelgrass (Zostera marina) on pore-water sulfide concentrations in intertidal sediments of Casco Bay, Maine
Date: 2016-05-01
Creator: Sabine Y Berzins
Access: Open access
- Eelgrass (Zostera marina) is a perennial seagrass that provides many vital ecosystem services including stabilizing sediments, maintaining water clarity, and providing complex habitat in the intertidal and shallow subtidal coastline. Historically, Maine supported dense eelgrass beds in shallow waters surrounding islands and along the coastal mainland. However, in 2012, high population densities of European green crabs (Carcinus maenas), which physically disturb and remove eelgrass as they forage, were correlated with widespread eelgrass declines. Over 55% of the area of eelgrass in Casco Bay was lost, mainly between 2012 and 2014. Eelgrass typically grows in low-oxygen sediments that produce a chemically reducing environment. Sulfate-reducing bacteria in these reduced sediments produce hydrogen sulfide, a toxin that can intrude into eelgrass tissues and impair the plants’ ability to photosynthesize. When eelgrass is not present, sulfide can build up in the pore-water. When eelgrass is present, it can oxygenate the sediments through its roots, thereby preventing the intrusion and buildup of toxic hydrogen sulfide. However, if the substrate is de-vegetated, oxygen levels drop as sedimentary organic matter is decomposed, and the accumulation of sulfides to harmful concentrations in the pore-water may make recolonization of eelgrass difficult or perhaps impossible even in the absence of green crabs. In an effort to monitor characteristics of Casco Bay eelgrass beds and determine spatially where eelgrass may be more likely to recover, four Casco Bay sites with varying degrees of vegetation loss were sampled in 2015 for pore-water sulfide concentration, sediment carbon and nitrogen content, and sediment grain size analysis. Measurements of sulfide concentrations showed correlations with the timing of eelgrass loss, such that vegetated sites had low pore-water sulfide concentrations and sites that had been de-vegetated for longer periods of time had high sulfide concentrations. Carbon and nitrogen content in the sediment was higher at de-vegetated sites, likely due to a higher percentage of finer sediments at those locations. Coarser sediments were more highly vegetated than finer sediments, perhaps displaying a preference of green crabs to forage in finer sediments. Catastrophic loss of eelgrass in Casco Bay has likely led to differences in sulfide levels, carbon and nitrogen content in the sediment, and grain size distribution, depending on degree of vegetation. Eelgrass restoration in Casco Bay will likely be limited by high pore-water sulfide concentrations.
Localizing Potential Messenger RNA Transport Protein Ips1 in Candida albicans Access to this record is restricted to members of the Bowdoin community. Log in here to view.
- Restriction End Date: 2027-06-01
Date: 2022-01-01
Creator: Yi Peng Wang
Access: Access restricted to the Bowdoin Community