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An Apple A Day: Have the Growing Conditions of Apples in Maine Changed Over the Past 20 Years
No full textClimate change is increasingly affecting the growing conditions that farmers face. This study focused on if and how the growing conditions of apples have changed over the past two decades. Apples are an economically, socially, and culturally important crop to Maine\u27s agriculture landscape. By production acreage, Maine is the second largest state in New England, with 2700 acres of land used to grow apples (USDA NASS CoA, 2022). A unique characteristic of agricultural production in Maine is that most farms are small-scale, run by families or small groups, making adverse changes to the growing conditions of a major crop in the region particularly harmful to people\u27s livelihoods.
This study aimed to identify change trends in climatic variables as these variables may influence what pests and pathogens will affect apple trees and the level of frost risk and damage apple blossoms and fruits face. I first identified the primary concern of apple growers in New England by interviewing farmers, orchardists, and cooperative extension agents across the region. I used answers from growers to identify what issues they experienced frequently and the level of damage these issues caused. I studied if Maine had experienced a change in average precipitation (mm). I also studied if the risk of frost exposure changed in the fall and spring. I assessed this by (a) measuring the frequency of freeze-thaw events during the fall and spring and (b) studying if the date of the first frost event in the fall and last frost event in the spring had shifted earlier or later (c) across 13 locations in Maine.
Using data from the Maine Pomological Society and NCEI-NOAA, I found that average precipitation was overall declining, but variability was present. For the entire state, the first day of fall frost has shifted 0.37 days later per year, and the last day of spring frost is inter-annually variable, as is the frequency of freeze-thaw cycles in the fall and spring. Overall, the growing conditions of apples in Maine experience many interannual variations, and the conditions growers face are unpredictable. This paper makes a few recommendations on how to preserve the productivity and fruit quality of orchards to deal with the observed interannual variability of growing conditions
The Relevance of Information on Effective Charitable Giving
No full textThe most effective charities are often more than a hundred times as effective as the average charity. However, top charities are not prioritized, and donation money is not used most effectively. To address this issue, it is crucial to understand why effective charitable giving is not prioritized. One factor identified in previous research is the limited access to cost-effectiveness information among donors. Our research explores whether providing individuals with different forms of information about charities leads to more effective donation decisions. Through an online RCT, individuals are separated into groups exposed to different types of information about two charities and asked to donate between the two. Specifically, we investigated whether people respond more strongly to information about overhead costs or to data on a charity’s effectiveness. We found that individuals donated more to charities with lower overhead costs but did not find statistically significant evidence that individuals donated differently when given information that a charity is more effectiv
Fair Play? Gender Equity, Title IX and Resource Allocation in College Athletics
No full textAmid a period of rapid transformation in college athletics, gender equity and Title IX remain underemphasized in the discourse. This study investigates disparities in athletic expenditure by gender, finding that in 2022, Division I institutions spent approximately 1.00 spent on women’s teams. While Title IX does not mandate equal spending, it does require that schools provide equitable experiences for male and female student-athletes. The persistence and magnitude of an expenditure gap call into question if schools are continuing to meet Title IX. This study identifies the characteristics of schools associated with less equal expenditure using data from the Equity in Athletics Database (EADA) and Integrated Postsecondary Education Data System (IPEDS) from 2014-2022. I find that the presence of a football program is associated with more equal spending both across the full sample and within Divisions I and III. Conversely, schools with higher acceptance rates, smaller athletic departments (as measured by the number of athletes), lower enrollments, lower tuition levels, and liberal arts colleges tend to be less equal in their expenditures
How does Cocaine Exposure Affect Early Gene Expression Changes in the Prefrontal Cortex (PFC) and Striatum?
No full textCocaine use disorder (CUD) remains a significant public health concern, yet the molecular mechanisms underlying individual susceptibility are poorly understood. This study investigates early transcriptional responses to acute cocaine exposure in two key brain regions implicated in addiction, the prefrontal cortex (PFC) and striatum, using genetically diverse Diversity Outbred (DO) mice. Paired tissue samples were collected following a standardized sensitization protocol and analyzed via bulk RNA sequencing. Differential expression analysis revealed 37 significantly differentially expressed genes in the striatum. These genes overlapped with gene sets associated with substance use, neurodevelopmental disorders, and immune signaling, implicating shared pathways in central nervous system homeostasis. Notably, Lbp, a regulator of TLR4/NF-κB–mediated neuroinflammation, was uniquely identified in a cocaine-specific context, suggesting a compensatory mechanism against cocaine-induced inflammatory signaling. Additionally, downregulation of Otx2, Msx1, and Cdkn1c in the dopaminergic neurogenesis pathway highlights a potential mechanism by which cocaine disrupts the development and maintenance of dopamine-producing neurons, thereby increasing addiction vulnerability. Together, these findings provide insight into early molecular adaptations to cocaine and identify neuroimmune and neurodevelopmental pathways as key contributors to individual differences in susceptibility to CUD
Full Issue - Spring 2023 - volume 110, issue 1
No full textSpring 2023, vol. 110 no. 1
04: From the Editor05: Table of Contents06. Downtown Colby14. Diagnosing Autism More Precisely16. An Inside Pitch22. Colby\u27s New Labs Address Critical Issues and Initiatives26. In Support of the Academic Mission28. A Building for Everybody36. Robust Financial Aid Program is Key to Colby\u27s Mission38. \u27Quite a Triumph\u2744. Class Notes66. Obituaries80. William R. Cotter, Colby\u27s Longest-Tenured Presiden
“Women who don’t know how to stay married”: The Poetic Afterlives of the 1927 Bristol Sessions
No full textThis project begins from the understanding that song lyrics can have lasting impacts on the poetic work that proceeds from them, and can and should, therefore, be read as literature. In the cultural context of Southern Appalachia, a historically underserved and academically underrepresented region, this understanding is intertwined with Audre Lorde’s idea that “For women...[poetry] is a vital necessity of our existence.” The women of Southern Appalachia, denied access to particular modes of expression as a result of external circumstances such as poverty and sexism, need poetry, according to Lorde, to take “tangible action” in their lives. What came before poetry in Southern Appalachia, a region rooted in oral tradition, however, was song. The most well-known collection of Southern Appalachian songs is the 1927 Bristol Sessions, though only a small percentage of these songs address Southern Appalachian women’s perspectives on marriage. Reading the Bristol Sessions lyrics as literature, this project examines Appalachian women poets’ resistance to heteronormative expectations for marriage over the last 100 years. If, as Lorde writes, poetry is as necessary as breathing for women and a way to incite change, then Appalachian women’s poetic reactions to heteronormativity are a powerful assertion of their right to exist and their right to have opinions about that existence. Ultimately, this project argues that the 1927 Bristol Sessions lyrics are the first life of the Appalachian counter-myth, which Appalachian women poets revived in an act of resistance. This act of resistance can be understood as the Bristol Sessions’ poetic afterlives
Prophets Instead of Priests: Diagonal Orientations & Coming-of-Age Queerness in Jane Eyre and Oranges Are Not the Only Fruit
No full textThis project asserts that the moment in which a girl leaves the trajectory of the expected in favor of the unknown in order to pursue her discovery of self is when her coming-of-age narrative becomes queer. This is demonstrated through Jane in Jane Eyre by Charlotte Brontë and Jeanette in Oranges Are Not the Only Fruit by Jeanette Winterson. Jane and Jeannette’s respective coming-of-age narratives–that is, them creating their fully embodied selves, the girl they believe and know themselves to be–happen off the expected life path in the liminal, in-between, undefined space of the queer oblique. There are moments in their narratives in which they must necessarily disorient themselves in order to grow. This project thus also asserts that queer depictions of girlhood are then inherently also depicting the forces of compulsory heterosexuality
The Value of a Vote: Vote Pivotality Information and Its Impact on Voter Willingness to Accept
No full textA variety of factors influence the decision to participate in a democratic election or not. This paper explores one of these factors: an individual’s perceived pivotality. I explore how people assess the value of their vote when they are informed about the likelihood that their vote will be pivotal. To do so, I conduct an online voting experiment where subjects participate in three different stylized elections: a marginal election, a landslide election, and an uninformed election (where the voter distribution is unclear to participants). I elicit participants’ vote valuations and compare them across election conditions and demographic groups using both mean and distributional measures. Results from the experiment indicate that participants as a whole value their vote more in marginal elections than in landslide elections. I also examine heterogeneous treatment effects by gender and race. In an election where the electorate distribution was unknown, men valued their vote as if they were in a marginal election, while women valued their vote as if they were in a landslide election. When uninformed about the electorate distribution, men behave as if their votes will be pivotal, while women behave as if their votes will not be pivotal. Heterogeneous treatment effects by race are inconclusive due to a small sample size, but preliminary results suggest similar differences to those of men and women
Local Limit Theorems on Finitely Generated Abelian Groups
No full textIn this thesis, we classify the pointwise behavior of finite-range random walks on finitely generated abelian groups in terms of local limit theorems. Random walks are central objects of research in probability theory, and the theory has found applications in statistics, physics, and even card shuffling. One significant topic in this line of study is random walks on finitely generated groups. Starting from the pioneering work of G. Pólya and H. Kesten, random walks on finitely generated groups have been studied extensively. However, many notable results on the subject (local limit theorems, for example) make assumptions about periodicity and irreducibility to avoid difficulties in analysis. In this thesis, we show that for finite-range random walks on finitely generated abelian groups, many such results can be stated in a form without such assumptions. Using tools from harmonic analysis, we formulate the local limit theorems in terms of a product of an attractor, which is in a uniform or Gaussian measure, and a prefactor (which we will refer to as a ``dance function ) that describes the periodic/reducible structure of the random walk. The result generalizes the classical results for random walks on an integer lattice and introduces a formalism of the local limit theorems without the aforementioned hypotheses. The results of this thesis will be presented in a forthcoming publication coauthored by the author and E. Randles
Microbial Degradation of Kelp-Derived Dissolved Organic Matter in the Context of Carbon Sequestration
No full textKelp, or brown algae, is an emerging form of ocean-based biological carbon dioxide removal, converting dissolved CO2 into organic molecules via photosynthesis. The export of detritus and dissolved organic carbon (DOC) from coastal beds to beyond the continental shelf contributes to carbon sequestration, especially through the microbial production of refractory DOC (RDOC). The influence of microbial degradation on kelp-derived DOC is not yet well understood, contributing to inconsistency in carbon sequestration estimates. This study utilizes dark bottle incubations of both blades and holdfasts from two farmed kelp species in the Gulf of Maine — Saccharina latissima and Saccharina angustissima — to examine the microbial processing of kelp-derived DOC over 90 days. The optical properties of chromophoric and fluorescent dissolved organic matter (CDOM and FDOM) were characterized using UV-VIS spectroscopy and excitation-emission matrix (EEMs) fluorescence spectroscopy. DOC and CDOM concentrations increased rapidly early in the experiment. While [DOC] proceeded to rapidly decrease, CDOM concentrations remained elevated through Day 90. Optical proxies for CDOM and FDOM suggest an upward trend in the humification of kelp-derived organic matter through Day 90 across all samples. Trends in average molecular weight and aromaticity varied by species and tissue type. EEMs red-shifts due to increased molecular complexity suggest the production of bio-recalcitrant DOC. Since changes in optical properties did not reach steady state by Day 90, definitive conclusions cannot be made on CDOM and FDOM contributions to carbon sequestration. However, these promising results encourage further work into the contribution of Maine-farmed kelp to biological CDR and carbon sequestration