The Pollination Biology and Mating System of a Peripheral Population of Witheringia solanacea (Solanaceae)

Pollinator visitation rates over the life of a flower are determined by pollinator abundance and floral longevity. If flowers are not visited frequently enough, pollen limitation may occur, favoring the evolution of self-compatibility (SC). In plant species with varying SC levels, central populations often are self-incompatible (SI) and peripheral populations are SC. Witheringia solanacea (Solanaceae) is a species that follows this trend with the exception of one population in the Monteverde Cloud Forest Reserve, which is peripheral yet SI. I investigated this population using multiple techniques including floral bagging, pollinator observations, microsatellite analysis, and floral longevity manipulations. My results confirmed the self-incompatibility of the Monteverde population and indicated low but perhaps adequate rates of pollinator visitation per flower per hour. I found reduced genetic diversity at Monteverde and gene flow occurring unidirectionally from San Luis (a central population) to Monteverde. In the greenhouse, there was more of an effect of male than female function on floral longevity, but the largest differences were environmental. Flowers stayed open substantially longer when cool, cloudy weather was simulated and shorter when conditions were hot and sunny. The results indicate that the Monteverde population of W. solanacea is SI because 1) it is unable to maximize its fitness due to gene flow from San Luis and its relatively recent colonization of the area and 2) pollen limitation may not be severe because of supplemental pollinator availability from other Witheringia species in the area and increased floral longevities due to cool and cloudy conditions.

Cytotoxicity of Diepoxybutane and Epichlorohydrin in Relation to Stages of the Cell Cycle

Work conducted in the Millard Biochemistry Research Laboratory examines the dual nature of molecules as carcinogens and anti-tumor agents through the molecular mechanisms of duplex DNA damage by bifunctional alkylating agents. Diepoxybutane (DEB) and epichlorohydrin (ECH) are polar molecules that form covalent DNA interstrand lesions by cross-linking the N7 position of deoxyguanosine residues. A recent experiment indicated that ECH preferentially targets nuclear DNA over mitochondrial DNA, whereas DEB shows similar rates of lesion formation for both loci. It was concluded that preferential targeting of nuclear DNA results from relatively poor uptake of ECH across the mitochondrial membrane. The objective of my honors research was to determine if the cytotoxicities of DEB and ECH vary according to the presence of the nuclear envelope in 6C2 chicken erythro-progenitor cells. The cytotoxicity of DEB and ECH was compared between cells randomly distributed throughout the cell cycle (Go/G, and S » G2/M) and cells enriched in G2/M stages. Results indicated that ECH is more cytotoxic than DEB in both unsynchronized control 6C2 cells and synchronized 6C2 cells enriched in G2/M stages of the cell cycle. Treatment with either bifunctional alkylating agent induced greater cytotoxicity in 6C2 cells enriched in G2/M stages than in unsynchronized control 6C2 cells, suggesting that the presence of the nuclear envelope-or any plasma membrane-may inhibit the reactivity of DEB and ECH.

Syntheses of Cross-Linking Agents, Molecular Modeling of Oligonucleotides and Polypeptide-Ion Complexes

Each section of this thesis will be subdivided into three parts encompassing all of the research in which I have been involved during the past three years. These will be referred to under the headings "Syntheses:' "Molecular Modeling," and "Cross-linking Efficiencies." Each of these subdivisions may have divisions within them when necessary in order to fully detail the research.

Therapeutic Discourse and the American Public Philosophy: On American Liberalism's Troubled Relationship with Psychology

I explore the main currents of postwar American liberalism. One, sociological, emerged in response to the danger of mass movements. Articulated primarily by political sociologists and psychologists and ascendant from the mid-fifties till the mid-seventies, it heralded the "end of ideology." It emphasized stability, elitism, positive science and pluralism; it recast normatively sound politics as logrolling and hard bargaining. I argue that these normative features, attractive when considered in isolation, taken together led to a vicious ad hominem style in accounting for views outside the postwar consensus. It used pseudo-scientific literature in labeling populists, Progressives, Taft conservatives, Goldwaterites, the New Left and others "pathological," viz. mentally ill. Hence, "therapeutic discourse." I argue that philosophical liberalism, which reasserts the role of political theory in working out norms and adjudicating disagreement, is a more profitable way of thinking about and defending from critics liberalism. I take the philosopher John Rawls as the tradition's modern representative. This inquiry is important because the themes of sociological liberalism are making a comeback in American public discourse, and with them perhaps the baggage of therapeutic discourse. I present a cautionary tale.

Investigating the Effects of Mifepristone (RU486) in the Behavioral, Hormonal and Central Responses to Acute Stress

Depression is associated with glucocorticoid hypersecretion, due to dysfunction of the hypothalamo-pituitary-adrenocorticol axis (HPA-axis). Because excess glucocorticoids are associated with depressive-like features in humans, glucocorticoid receptor antagonists are currently being tested for antidepressant efficacy in clinical trials. In the current study the hypothesis that mifepristone (RU486), a glucocorticoid receptor antagonist, would decrease the neuroendocrine and central HPA-axis responses to an acute stressor and attentuate depressive like behavior in an animal model of behavioral helplessness (forced swim test) was tested. Adult male rats were treated with 10 mglkg RU486 (subcutaneous) for five days and then exposed to a IO-minute forced swim test (FST), conducted in Plexiglas cylinders. FST sessions were videotaped for later analysis of behavioral immobility. Plasma ACTH and corticosterone CORT were measured at 15min and 90min after FST cessation. Animals were perfused and brains were collected for immunocytochemical assessment of c-Fos expression in the medial prefrontal cortex (mPFC), a brain region implicated in both depression and central control of the HPA axis. RU486 significantly decreased peak ACTH and CORT concentrations following FST exposure. In addition, glucocorticoid negative feedback was at1enuated in RU486-treated animals exposed to the FST. Exposure to FST alone induced c-FOS expression in the mPFC, as measured by the number of c-Fos positive neurons. Treatment with RU486 significantly increased the number of rnPFC c-Fos positive cell following FST exposure. The behavioral data obtained from FST paradigm, demonstrated that RU486 decreased immobility in the FST illustrating the potential efficacy of this drug as an antidepressant. Collectively these data suggest that RU486 dampens HPA-axis responses to stress, possibly by enhancing the excitability of stress-inhibitory neurons in the mPFC. This is particularly exciting, given the fact that this neural region is associated with decreased neural activity during depression in humans.

The Effects of Eating Behaviors and Exercise Patterns on the Processing of Food and Exercise Related Stimuli

The effectiveness of Cognitive Behavioral Therapy (CBT) for eating disorders has established a link between cognitive processes and unhealthy eating behaviors. However, the relationship between individual differences in unhealthy eating behaviors that are not related to clinical eating disorders, such as overeating and restrained eating, and the processing of food related verbal stimuli remains undetermined. Furthermore, the cognitive processes that promote unhealthy and healthy exercise patterns remain virtually unexplored by previous research. The present study compared individual differences in attitudes and behaviors around eating and exercise to responses to food and exercise-related words using a Lexical Decision Task (LDT). Participants were recruited from Colby (n = 61) and the greater Waterville community (n = 16). The results indicate the following trends in the data: Individuals who scored high in “thin ideal” responded faster to food-related words than individuals with low “thin Ideal” scores did. Regarding the exercise-related data, individuals who engage in more “low intensity exercise” responded faster to exercise-related words than individuals who engage in less “low intensity exercise” did. These findings suggest that cognitive schemata about food and exercise might mediate individual’s eating and exercise patterns.

Hamiltonian constraint analysis of vector field theories with spontaneous Lorentz symmetry breaking

Recent investigations of various quantum-gravity theories have revealed a variety of possible mechanisms that lead to Lorentz violation. One of the more elegant of these mechanisms is known as Spontaneous Lorentz Symmetry Breaking (SLSB), where a vector or tensor field acquires a nonzero vacuum expectation value. As a consequence of this symmetry breaking, massless Nambu-Goldstone modes appear with properties similar to the photon in Electromagnetism. This thesis considers the most general class of vector field theories that exhibit spontaneous Lorentz violation-known as bumblebee models-and examines their candidacy as potential alternative explanations of E&M, offering the possibility that Einstein-Maxwell theory could emerge as a result of SLSB rather than of local U(1) gauge invariance. With this aim we employ Dirac's Hamiltonian Constraint Analysis procedure to examine the constraint structures and degrees of freedom inherent in three candidate bumblebee models, each with a different potential function, and compare these results to those of Electromagnetism. We find that none of these models share similar constraint structures to that of E&M, and that the number of degrees of freedom for each model exceeds that of Electromagnetism by at least two, pointing to the potential existence of massive modes or propagating ghost modes in the bumblebee theories.

Natural Theology: A Reevaluation of Christianity's Relationship to the Natural World

In this thesis I offer two separate arguments for the creation of an environmentally friendly Christian theology. These arguments, although interconnected, are roughly divided into the main chapters of the thesis. I will begin in Chapter Two by offering a negative argument against the assumption that the natural world is sinful. In their article Hauerwas and Berkman suggest that the suffering of animals is both an example of the sinful state of the environment and a justification for human separation from an unholy natural environment. In response to this view I will argue in the second chapter that the suffering of animals can be seen as part of God's intentions for our world. Suffering, in both the human and the larger world, is not evidence of a fundamental flaw in natural systems. Instead, the cycle of death and life found in the natural world can be profoundly spiritual.

Where did all these books come from? The Publishing Industry and American Intellectual Life

The American book publishing industry shapes the character of American intellectual life. While the newspaper and television industries have been accused of and investigated for bias and lowering America’s intellectual standards, book publishing has gone largely unexamined by scholars. The existing studies of the publishing industry have focused on finance, procedure and history. “There are few ‘theories’ of publishing – efforts to understand the ‘whys’ as well as the ‘hows.’ Few scholarly scientists have devoted significant scholarly attention to publishing” (Altbach and Hoshino, xiii). There are many possible reasons for this lacuna. First, there is a perception that books have always been around, that they are an “old” technology and therefore they don’t appear to have had as much of an impact on our society as television and other media (which were developed quickly and suddenly) seem to have had (Altbach and Hoshino, xiv). Also, despite books’ present and past popularity, television, radio, and now the internet reach more people more easily, and are therefore more topical points of study and observation. In studying the effects of mass media on everyday American life, television and the internet may be the most logical points of study. Regarding public intellectual life however, books play a much more important role. Public intellectual life has always been associated with independent thinkers publishing their work for the masses. For this reason, this I focus on trade publishing. Trade publishing produces fiction and non-fiction works for the general reading public, as opposed to technical manuals, textbooks, and other fiction and nonfiction books targeted to small and specific audiences. Although, quantitatively speaking, “the largest part of book publishing business is embodied in that great complex of companies and activities producing educational, business, scientific, technical, and reference books and materials,” (Tebbel 1987, 439) the trade industry publishes most of the books that most people read. It is the most public segment of the industry, and the most likely place to find public intellectualism. Trade publishing is not only the most public segment of the industry, but it is also the most susceptible to corruption and lowered intellectual standards. Unlike specialty publishing, which caters to a specific, known segment of society, trade publishers must compete with countless other publications, as well as with other forms of media, for the patronage of the general public. As John Tebbel (author of a widely referenced history of the publishing industry) puts it, “The textbook, scientific, or technical book is subjected to much more rigorous scrutiny by buyers and users, and in an intensively competitive market inferior products are quickly lost" (Tebbel 1987, xiv). Since the standards for trade publishing are not nearly as specific – trade books simply need to catch the attention of a significant number of readers, they don’t have to measure up to a given level of quality – the quality of trade books is much more variable. And yet, a successful trade publication can have a much greater impact on society than the most rigorously researched and edited textbook or scholarly study.

Impact of the 1980 election on ideological liberal organizations

Throughout this section, I sought to establish a nexus between interest group theory and empirical observations. This in turn, would provide the framework from which I would set forth a series of hypotheses concerning the impact of the deviating 1980 elections on ideological liberal organizations. What I found in fact, was not just a link but a near perfect correlation between theory and practice, each reinforcing the other and pointing to the same ineluctable conclusion: The upshot of the Reagan/New Right landslide of 1980 was a dramatic renaissance of American liberalism. A renaissance so pervasive that ideological liberal organizations stand to benefit tremendously in terms of sustaining membership and raising funds. Moreover, it promises to facilitate the formation of liberal lobbying coalitions and enhance their capacity to cultivate grass roots support.

The “Lunatic Fringe” -- Barry Goldwater and the Conservative Revolution of the 1960s --

How did conservatives, who had become effectively ostracized by their party following the Great Depression and the societal reforms of the New Deal, regain leverage within the GOP during the 1960s? My hypothesis is two-fold. First, I contend that a small group of conservative activists led by F. Clifton White, in spite of a dearth of resources and manpower, managed to infiltrate Republican infrastructure and “hijack” the delegate- selection process. The distinctly conservative and recalcitrant disposition of the Goldwater delegates demonstrates that these activists succeeded. Second, I argue that in addition to temporarily overpowering the national convention in 1964, conservatives thereafter retained control of the party insofar as subsequent GOP candidates were obliged to garner the support of conservative pockets of the country in order to win the presidential nomination. The resulting rightward shift of the Republican Party following the 1960s is a direct corollary of the conservative takeover outlined in this study.

Literary love making in Nicholas Sparks novels: Finding the balance between the writer’s life and the writer’s work in bestselling Romantic Literature

For almost a decade now Nicholas Sparks has been writing love stories. Not only has he been publishing his stories, but they have received high acclaim in each of their installments. Several of his novels have been made into major motion pictures and increased his popularity quite significantly. His status as a successful romantic fiction writer is undeniable, but the question is, why? What is it about Nicholas Sparks that makes his novels so engaging, and personally, what do I need to do as an aspiring novelist to try and acquire the same literary status? Sparks’s novels reach readers at a number of different levels, thus giving them appeal no matter the intellectual intent of the reader. Theoretically, Sparks engages reader response techniques as well as formalist processes such as “habitualization” and “defamiliarization,” while also developing engaging plot lines that represent many of the experiences from his own life. His writing is not only academically redeemable, but it is also creatively stimulating; between the two, Sparks represents the thunder and lightning combination all writers strive for while trying to achieve literary success. This project also offers a creative element in which I attempt to exemplify many of the traits discussed in the analytical sections of this document, by recreating them in a creative, fictitious fashion. Themes such as: motion versus stasis, life versus death, and the ordinary versus the extraordinary all exist within the narrative structure of my short story “Trip to Fall.” Besides these thematic elements, the creative section strives to represent the balance Sparks achieves between the experiences of his own life and the fictitious world he creates. Overall, this project delves into the life of Nicholas Sparks to better understand the inspiration for his writing at the level of form as well as content, while also paying tribute to Sparks’s style through a representation of his work in my own words.

Life and Death: The Religious, Philosophical and Moral Dilemmas in Medicine

Religious beliefs often play a major role in the decisions that are made in the home and the hospital concerning issues at the beginning and end of life. Only recently, however, due to rapidly advancing medical technology, have religious, moral, and philosophical beliefs taken such a controversial role. One of the major questions that has arisen from these various controversies is whether or not we have the right to posses control over the biological functions of our bodies. The answer is a difficult one, and it may be one that cannot be answered, but the attempt at an answer is what is at the heart of medical ethics.

Interactions of Electrons and Rydberg Atoms in Ultra-Cold Plasmas

This thesis discusses an experimental technique for investigating electron temperature control by Rydberg atoms in ultra-cold plasmas. The objective we set ourselves was twofold. Firstly, we sought to gain an insight into the processes whereby the creation of Rydberg atoms within the plasma lengthens the lifetime of the plasma. To this end, we created the plasma using a Littman dye laser and subsequently, at a variable time delay, we excited neutral atoms in the plasma to specific Rydberg states using a narrow bandwidth pulsed dye laser. Secondly, we employed radio-frequency (rf) electric fields to excite electron oscillations within the plasma in order to infer such information as plasma density and electron temperature. Although we found that the introduction of high angular momentum Rydberg states did lengthen the plasma lifetime we were not able to differentiate between the temperature moderation effect due to the Rydberg atoms cooling the plasma, and the binding effect due to an increased positive space charge within the plasma.

The Schwarmgeister: The Development of Ecclesiastical Doctrine Through Schismatic Movements

Throughout the Christian story, Church doctrine and ecclesiology have been shrouded in controversy. From the Council of Nicea in 325, when are early Church fathers debated about the Trinity of Christ all the way to the modern day with Vatican II theological controversies have been important in the molding of Christian doctrine on the structure, role, and function of the Church. What makes those controversies different from the ones I treat in my thesis is that the previously mentioned controversies did not lead to schismatic divisions in the Church. The Donatist controversy and Luther's theological battle with Karlstadt were major movements that endangered the unity of the Church. These controversies propagated crucial writings and teachings in two major areas. The first area is the spiritual power and validity of the sacraments. Second is the role, function, and ecclesiology of the Church, with particular attention to the authority of the ministry. I want to demonstrate that these controversies refined the Church's thinking on sacramental issues such as baptism and Eucharist, as well as address the question of who has the power in the Church? And to what extent do they have the power to press reforms?