Showing 141 - 150 of 583 Items
Examining Functional Roles for Anthocyanins in Plant Leaves Access to this record is restricted to members of the Bowdoin community. Log in here to view.
Date: 2016-05-01
Creator: Benjamin M West
Access: Access restricted to the Bowdoin Community
Deciphering Policymaking—The Enigma of the 2003 Iraq War
Date: 2024-01-01
Creator: Chengkai Gu
Access: Open access
- This thesis examines the forces shaping the United States’ decision to initiate the 2003 Iraq War. It argues that while the Bush administration had vested interests in disarming Iraq to eliminate Saddam Hussein’s military threat and to secure stable global oil supplies, the decision-making process leading to the Iraq War was heavily influenced by domestic politics, such as bureaucratic bargaining, CIA intelligence collections, and interest group competition. In addition, individual-level factors, such as top officials’ personal beliefs and psychologies, also shaped the decision to intervene in Iraq. By explaining how strategic, domestic, and personal factors interacted to shape the decision to launch the Iraq War, my study underscores the impact of less obvious micro-level dynamics on international politics and the multi-layered nature of foreign policymaking.
Three Decades of Replicated Field Studies Reveal Eelgrass (Zostera marina) Inhibits Soft-shell Clam (Mya arenaria) Growth in Eastern Maine This record is embargoed.
- Embargo End Date: 2027-05-16
Date: 2024-01-01
Creator: Everett Horch
Access: Embargoed
Non-Naturalism and Naturalism in Mathematics, Morality, and Epistemology
Date: 2018-05-01
Creator: Nicholas DiStefano
Access: Open access
He Mauka Teitei, Ko Aoraki, The Loftiest of Mountains: The Names of Aotearoa’s Highest Peak and Beyond
Date: 2024-01-01
Creator: Joseph B. Lancia
Access: Open access
- My thesis discusses the cultural, political, and social dynamics of mountains with separate Indigenous and Western names and identities. Centering on Aoraki/Mount Cook—the highest peak in Aotearoa New Zealand—I integrate personal experiences as ethnographic data through narratives, mainly of my time hiking while studying abroad in New Zealand and during the two recent summers I spent exploring Rocky Mountain National Park in Colorado. Through its name, Aoraki/Mt. Cook maintains Indigenous Māori and Western perspectives: Aoraki being a Māori atua (god) and Captain James Cook being a significant colonial figure in the Pacific. The slash upholds both identities while ensuring that they exist together. These dynamics are explored in depth and extended to mountains in places including Colorado, Alaska, and Australia. While discussing Rocky I rely heavily on Oliver Toll’s Arapaho Names & Trails (2003) which contains a substantial collection of Arapaho knowledge of the area and I give strong attention to Nesótaieux (Longs Peak and Mount Meeker). Additionally, I look at Mount Blue Sky, Denali, and Uluru/Ayers Rock to discuss mountains that have had formal name changes and how legacies are maintained through toponyms. With discussing varying identities and perceptions of each example and the knowledge held in names I encourage readers to do research into local Indigenous knowledges to further their and others’ understandings of places. I emphasize the concepts of historical silences, the revealing of knowledge, and the importance of language to articulate that Indigenous knowledge might be difficult to find but is never truly lost.
Fall forward, spring back: Drivers of synchrony in the sea star crawl-bounce gait transition
Date: 2024-01-01
Creator: Brady R Nichols
Access: Open access
- The Froude number is the ratio of kinetic energy to gravitational potential energy used during locomotion and is often used to analyze gait transitions. Here, I compare and contrast the human walk-run gait transition, which occurs at a consistent Froude number of 1 because there exists a mechanical speed limit to walking, and the sea star crawl-bounce gait transition, which occurs around Froude numbers of 1*10^-3. In this thesis I investigate why sea stars exhibit two gaits despite lacking brains and moving at Froude numbers far below other known gait transitions, hypothesizing (1) that the crawl-bounce transition may be mechanical and thus still depends on the Froude number, and (2) that the crawl-bounce transition is best modeled gradually compared to the instantaneous human walk-run transition. Thirty sea stars were filmed and the resulting kinematic data is used here to inform thinking about the crawl-bounce transition. I first discuss damped driven harmonic motion of a single oscillator, but eventually turn to using coupled oscillators and deriving that a coupling constant between metronomes on a moving base is the Froude number, which is therefore relevant for the crawl-bounce transition. I lastly discuss a purely mathematical analogue of the crawl-bounce transition as a Hopf bifurcation in horizontal speed and vertical velocity phase space, which leads to a rough model with results qualitatively similar to observed kinematic data from films, and indicates that a gradual transition is in fact a good fit for the crawl-bounce transition.
Origin of Rhyolite from Magma Mush: Plutonic Lithics from the Ohakuri Ignimbrite, Taupō Volcanic Zone, New Zealand This record is embargoed.
- Embargo End Date: 2027-05-15
Date: 2024-01-01
Creator: Christine Reimer
Access: Embargoed
Policy Making, Decision Making, and Advocacy: The U.S. Asylum System Since 9/11
Date: 2024-01-01
Creator: Clara Jergins
Access: Open access
- Immigration justice advocates and immigration restrictionists alike are unhappy with the way that the U.S. asylum system functions. This project seeks to develop a better understanding of policy changes and the politicized influence of the president and executive authorities over the asylum system since 9/11—in particular, these individuals’ ability to implement their policy preferences through the hiring and instruction of Asylum Officers and Immigration Judges. Through case studies of nonprofit organizations, it identifies the key points in the asylum process where asylum has been restricted, and the ways in which these restrictions can be responded to. On the basis of these factors, this project identifies four key changes, made by Congress, through which the asylum system could be improved: the establishment of an Article I immigration court, encoded testimonial and credibility standards, universal representation, and an end to asylum seeker detention. These changes are asserted to depoliticize the asylum process and to create a stable asylum system in which those that should qualify for asylum do qualify.
DS-PSO: Particle Swarm Optimization with Dynamic and Static Topologies
Date: 2017-05-01
Creator: Dominick Sanchez
Access: Open access
- Particle Swarm Optimization (PSO) is often used for optimization problems due to its speed and relative simplicity. Unfortunately, like many optimization algorithms, PSO may potentially converge too early on local optima. Using multiple neighborhoods alleviates this problem to a certain extent, although premature convergence is still a concern. Using dynamic topologies, as opposed to static neighborhoods, can encourage exploration of the search space at the cost of exploitation. We propose a new version of PSO, Dynamic-Static PSO (DS-PSO) that assigns multiple neighborhoods to each particle. By using both dynamic and static topologies, DS-PSO encourages exploration, while also exploiting existing knowledge about the search space. While DS-PSO does not outperform other PSO variants on all benchmark functions we tested, its performance on several functions is substantially better than other variants.
Functional redundancy of a non-native foundation species (eelgrass, Zostera japonica) across intertidal stress gradients
Date: 2023-01-01
Creator: S. Maria Garcia
Access: Open access
- Non-native species foundation species can alter ecosystems in both positive and negative ways. The creation of habitat can be beneficial to native species when they provide a limiting resource or in a stressful environment. Yet this creation of habitat can also be detrimental by replacing native species and/or facilitating the presence of more non-native species. In Willapa Bay, WA, a non-native foundation species, Zostera japonica, co-exists with the native foundation species Zostera marina. Zostera japonica persists at the higher intertidal in monocultures, the two species overlap in the mid intertidal, and Z. marina persists in monocultures in the low intertidal. Epifaunal invertebrates, the organisms that live on eelgrass blades, connect eelgrass to higher trophic levels. Through a series of transplants and removals, I used this zonation pattern to ask if the two species can fulfill a similar functional role in respect to epifaunal invertebrates (functional redundancy), and if this was due to the identity of the foundation species or a response to the stress gradient of the intertidal. My results suggest that the epifaunal invertebrate community is responding more to the physiological stress gradient, and the functional redundancy of the two species depends on the location they are found. Z. japonica is expanding the range of vegetated habitat into to the physiologically stressful high zone, which supports a different community. This experiment highlights that the impacts of non- native species are highly localized and that abiotic and biotic factors are important to trophic interactions.