Showing 301 - 310 of 583 Items
Mitochondrial adaptation in the green crab hybrid zone of the Gulf of Maine
Date: 2024-01-01
Creator: Jared Lynch
Access: Open access
- The mitochondrial genome has historically been relegated to a neutral genetic marker, but new evidence suggests mitochondrial DNA to be a target for adaptation to environmental stress. The invasive European green crab (Carcinus maenas) exemplifies this in the Gulf of Maine’s hybrid zone, where interbreeding populations exhibit thermal tolerances influenced by mitochondrial genotype. To better understand the mechanism behind this phenomenon, the effect of mitochondrial genotype on mitochondrial activity was tested by measuring mtDNA copy number (mtCN) and the activity of complex I, II, and IV of the electron transport system via high-resolution respirometry. Mitochondria isolated from frozen heart tissue were measured at three temperature points—5°C, 25°C, and 37°C—to represent thermal stresses and a control. It was predicted that cold-adapted haplogroups would exhibit both higher mtCN and increased activity for each complex, either across all temperatures or exclusively at 5°C compared to a warm-adapted haplogroup. Initial comparisons of mitochondria from fresh and frozen tissue at 25°C found lower activity for complex II and IV in frozen extracts, but they continued to be used for convenience. No differences were observed across haplogroups for mtCN or high-resolution respirometry, suggesting that mitochondrial activity does not underlie differences in thermal tolerance. However, temperature greatly influenced activity measurements with complex II and IV exhibiting the highest rates at 37°C while complex I exhibited optimal activity at 25°C. This study represents the first of its kind for C. maenas, providing a foundation for future experiments to continue exploring mitochondria in the context of adaptive evolution.
Salud Callejera: Mobilizing Cuidado at the Margins of Neoliberalism; Reimagining Care for People Experiencing Homelessness in Buenos Aires
Date: 2019-05-01
Creator: Brandon Morande
Access: Open access
- On any given night, thousands of individuals sleep on the streets of the Ciudad Autónoma de Buenos Aires. Without secure housing, people in situación de calle (experiencing homelessness) suffer elevated rates of physical trauma, transmissible and chronic diseases, and symptoms of depression. Nevertheless, two-thirds of this population do not receive annual health consultations, with the majority solely accessing the emergency department when their conditions severely worsen. This study finds that municipal services and, to a lesser extent, the public health system render individuals responsible for housing insecurity by adopting a neoliberal subjectivity of homo economicus, medicalizing poverty as a symptom of psychosocial illness potentially curable through economic and social rehabilitation. Those who do not conform with such pathologization or other employment-based demands confront heightened criminalization and exclusion from care services. As an alternative response, this project investigates the actions of civil society networks, which employ a contrary notion of homo politicus, reimagining care as a collective right and site of political mobilization. This thesis draws upon interviews with people experiencing or at risk of homelessness, members of civil society organizations, public health providers, and municipal social workers, as well as observations from street-outreach.
This is What You Want: Stories
Date: 2017-05-01
Creator: Savannah Blake Horton
Access: Open access
- This is What You Want: Stories is a collection of nine stories exploring the role of humor in dark situations. It is a work of fiction.
Virtual Reality Accessibility with Predictive Trails
Date: 2020-01-01
Creator: Dani Paul Hove
Access: Open access
- Comfortable locomotion in VR is an evolving problem. Given the high probability of vestibular-visual disconnect, and subsequent simulator sickness, new users face an uphill battle in adjusting to the technology. While natural locomotion offers the least chance of simulator sickness, the space, economic and accessibility barriers to it limit its effectiveness for a wider audience. Software-enabled locomotion circumvents much of these barriers, but has the greatest need for simulator sickness mitigation. This is especially true for standing VR experiences, where sex-biased differences in mitigation effectiveness are amplified (postural instability due to vection disproportionately affects women). Predictive trails were developed as a shareable Unity module in order to combat some of the gaps in current mitigation methods. Predictive trails use navigation meshes and path finding to plot the user’s available path according to their direction of vection. Some of the more prominent software methods each face distinct problems. Vignetting, while largely effective, restricts user field-of-vision (FoV), which in prolonged scenarios, has been shown to disproportionately lower women’s navigational ability. Virtual noses, while effective without introducing FoV restrictions, requires commercial licensing for use. Early testing of predictive trails proved effective on the principal investigator, but a wider user study - while approved - was unable to be carried out due to circumstances of the global health crisis. While the user study was planned around a seated experience, further study is required into the respective sex-biased effect on a standing VR experience. Additional investigation into performance is also required.
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Photochemistry of Cyano-Substituted 8-Amino-2-Naphthol This record is embargoed.
- Embargo End Date: 2026-05-20
Date: 2021-01-01
Creator: Jialin Xie
Access: Embargoed

Freezing temperatures drive functional trait clustering more than habitat structure in eelgrass communities in the Gulf of Maine This record is embargoed.
- Embargo End Date: 2026-05-18
Date: 2023-01-01
Creator: Bridget Marjorie Patterson
Access: Embargoed

Accounting for Gender Differences in Cultural Industries: Evidence from Film and the Fine Arts Access to this record is restricted to members of the Bowdoin community. Log in here to view.
Date: 2020-01-01
Creator: Madeleine Rose Dupré
Access: Access restricted to the Bowdoin Community
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Egg Size, Breeding Phenology, and Parental Investment in Leach’s Storm Petrels Access to this record is restricted to members of the Bowdoin community. Log in here to view.
Date: 2020-01-01
Creator: James L. O'Shea
Access: Access restricted to the Bowdoin Community
Brutal Encounters: Primitivity, Politics, and the Postmodern Revolution
Date: 2021-01-01
Creator: Archer Thomas
Access: Open access
- The switch from late modernism to postmodernism in Western aesthetic theory and criticism took place in the mid-to-late 20th century, radically changing the face of cultural criticism. Much has been written on how postmodernism broke from modernism, but what factors paved its way in the decades following the Second World War? This paper argues that postmodernism represents both a reaction to and a necessary evolution of late modernism, specifically as it manifests in architecture, politics, and the politics of architecture. It focuses on the crisis of confidence among Western left-wing circles following the upheaval of the Second World War and posits that, because of this upheaval, primitivism came to dominate the epistemology of a renewed modernism led by figures such as Clement Greenberg, Reyner Banham, and the practitioners of “the New Brutalism.” The paper then explores how the Western left-wing reaction to developments like decolonization and postwar modernization challenged primitivity’s newfound importance, resulting in a shift towards a “postmodern populism” in aesthetics and politics by the 1960s as described by Jean Baudrillard, Fredric Jameson, Robert Venturi, and Reyner Banham.
How do long-term above-ground biomass dynamics vary between different forest stand types at Harvard Forest?
Date: 2023-01-01
Creator: Maya Y. Chandar-Kouba
Access: Open access
- Monitoring forest carbon storage is necessary in accurately modelling the global carbon cycle. In the Northeast, terrestrial forests represent a major carbon sink with above-ground biomass (AGB) accounting for 40% of stored forest carbon. Therefore, understanding how AGB varies spatiotemporally is essential in predicting future carbon storage. Repeated measurements in permanent, long-term plots provide an opportunity to examine how carbon stored in AGB is changing over time. I used 29 years of data from the Harvard Forest Environmental Monitoring Systems (HF EMS) Site to determine how stand composition, intrinsic factors, and extrinsic environmental factors influenced rates of carbon storage in AGB over time. Using a partition around medoids (PAM) clustering method, I separated the 34 ground plots at the EMS stand into their respective stand types. I found that each stand type at the HF EMS plots accumulates carbon at consistent rates throughout the study period, although rates of carbon accumulation between stands were significantly different. Red Pine stands experience a rapid decline in biomass in 2018 due to the introduction of the Southern Pine Beetle. Across all stand types, sporadic mortality events determine variations in yearly rates of carbon accumulation, although this has little significant influence on total AGB accumulation. Leaf area index (LAI) and foliar N contents have no effect on growth increments. Extrinsic environmental variables had mixed effects on growth and mortality, highlighting the complexities of predicting forest carbon storage under changing climate conditions.