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George J. Mitchell Oral History Project
- Between 2008 and 2011, the Bowdoin College Library conducted an oral history project to create a collection of spoken recollections and personal impressions from individuals who have known George J. Mitchell in a variety of ways. These oral histories document his life and career from early childhood onward, with particular emphasis on his public service to Maine and to the nation, and they complement his personal papers, which are also held by Bowdoin College. Interviewees include Senator Mitchell's Waterville (Maine) friends and acquaintances; family members; college classmates; Maine legislators; political associates and competitors; campaign supporters; U.S. Senate colleagues and staff members; public agency officials; foreign policy specialists; law practice associates; public policy advocates; board members of various affiliations; and friends. Because oral history recordings are intrinsically informal, spontaneous, and candid, they characterize events and personalities in ways that are otherwise silent in the historical record. In particular, they capture personal knowledge and institutional memory about people, occasions, and processes that are rarely documented elsewhere. Thus, these oral histories provide an invaluable resource in understanding both the recent past and how individuals have played essential roles in shaping the present. TRANSCRIPT GUIDELINES Every attempt has been made to create transcripts that reflect the recorded interviews accurately. Interviewees were given the opportunity to edit their transcripts to correct errors of transcription and fact (often, for example, a recollection might have included a misremembered date or place), or to enhance clarity of expression. Additions and minor deletions or changes are indicated in the transcript by closed brackets ([ ]); more substantive omissions are noted as: [p/o] (i.e. “[phrase omitted]”). ATTRIBUTION These recordings and transcripts are provided for educational use, private study, and research. Brief quotations for academic purposes and other uses that fall within “fair use” (Title 17, United States Code) require proper attribution customary to the discipline or community. All other uses not protected by “fair use,” including derivation, publication, and reproduction, require written permission from Bowdoin College. In citing these interviews, specify the interviewee, interviewer, and interview date following the style found in the example below: George J. Mitchell, interview by Andrea L’Hommedieu, 10 May 2011, George J. Mitchell Oral History Project, Bowdoin College Library, Brunswick, Maine.
Bowdoin College Catalogue (1941-1942)
Date: 1942-01-01
Access: Open access
- Bowdoin College Bulletin no. 260
Search for exclusive b→u semileptonic decays of B mesons
Date: 1993-01-01
Creator: A. Bean, J. Gronberg, R. Kutschke, S. Menary, R. J., Morrison, H. N. Nelson, J. D. Richman, H. Tajima, D. Schmidt, D. Sperka, M. S. Witherell, M. Procario, S. Yang, R. Ballest, M. Daoudi, W. T. Ford, D. R. Johnson, K. Lingel, M. Lohner, P. Rankin, J. G. Smith, J. P. Alexander, C. Bebek, K. Berkelman, D. Besson, T. E. Browder, D. G. Cassel, H. A. Cho, D. M. Coffman, P. S. Drell, R. Ehrlich
Access: Open access
- Using a sample of 935 000 BB̄ pairs collected with the CLEO-II detector at the Cornell Electron Storage Ring, we have obtained upper limits on the branching ratios for the b→ul-ν̄ processes B-→ωl- ν̄, B-→ρ0l-ν̄, and B̄0→ρ+l-ν̄. The combined result using the relationships among the widths for these three modes is B(B-→ρ0l-ν̄)<(1.6-2.7)×10-4 at 90% C.L., where the range of values is due to model dependence of the detection efficiencies. These measurements yield the limits Vub/Vcb<0.08-0.13. © 1993 The American Physical Society.
Differential neuropeptide modulation of premotor and motor neurons in the lobster cardiac ganglion
Date: 2020-10-01
Creator: Emily R. Oleisky, Meredith E. Stanhope, J. Joe Hull, Andrew E. Christie, Patsy S., Dickinson
Access: Open access
- The American lobster, Homarus americanus, cardiac neuromuscular system is controlled by the cardiac ganglion (CG), a central pattern generator consisting of four premotor and five motor neurons. Here, we show that the premotor and motor neurons can establish independent bursting patterns when decoupled by a physical ligature. We also show that mRNA encoding myosuppressin, a cardioactive neuropeptide, is produced within the CG. We thus asked whether myosuppressin modulates the decoupled premotor and motor neurons, and if so, how this modulation might underlie the role(s) that these neurons play in myosuppressin's effects on ganglionic output. Although myosuppressin exerted dose-dependent effects on burst frequency and duration in both premotor and motor neurons in the intact CG, its effects on the ligatured ganglion were more complex, with different effects and thresholds on the two types of neurons. These data suggest that the motor neurons are more important in determining the changes in frequency of the CG elicited by low concentrations of myosuppressin, whereas the premotor neurons have a greater impact on changes elicited in burst duration. A single putative myosuppressin receptor (MSR-I) was previously described from the Homarus nervous system. We identified four additional putative MSRs (MSR-II-V) and investigated their individual distributions in the CG premotor and motor neurons using RT-PCR. Transcripts for only three receptors (MSR-II-IV) were amplified from the CG. Potential differential distributions of the receptors were observed between the premotor and motor neurons; these differences may contribute to the distinct physiological responses of the two neuron types to myosuppressin. NEW & NOTEWORTHY Premotor and motor neurons of the Homarus americanus cardiac ganglion (CG) are normally electrically and chemically coupled, and generate rhythmic bursting that drives cardiac contractions; we show that they can establish independent bursting patterns when physically decoupled by a ligature. The neuropeptide myosuppressin modulates different aspects of the bursting pattern in these neuron types to determine the overall modulation of the intact CG. Differential distribution of myosuppressin receptors may underlie the observed responses to myosuppressin.
Natural variation in chromatin conformation among populations of Drosophila melanogaster
Date: 2021-01-01
Creator: Utku Ferah
Access: Open access
- The role of polymorphisms in protein-coding and non-coding regions of the genome during adaptive evolution has been a long-debated subject in evolutionary biology. Although the importance of coding-sequence polymorphisms during evolution has been well-documented, the influence of non-coding regions of the genome on phenotypic diversity and adaptive evolution remains less clear. Enhancers are cis-regulatory elements that dictate gene transcription rates, times, and locations; enhancers are located in noncoding regions and, when active, exhibit an open-chromatin conformation. In the current study, we identified putative enhancers that differ in chromatin conformation among three natural isolates of Drosophila melanogaster from different parts of the world. The genome-wide numbers of enhancers active in some natural isolates—but inactive in others—will provide insight into the amount of raw material available for evolution due to transcriptional regulatory variation.
Bowdoin College Catalogue (1972-1973)
Date: 1973-01-01
Access: Open access
- Bowdoin College Bulletin no. 386
Approximate initial data for binary black holes
Date: 2006-09-21
Creator: Kenneth A. Dennison, Thomas W. Baumgarte, Harald P. Pfeiffer
Access: Open access
- We construct approximate analytical solutions to the constraint equations of general relativity for binary black holes of arbitrary mass ratio in quasicircular orbit. We adopt the puncture method to solve the constraint equations in the transverse-traceless decomposition and consider perturbations of Schwarzschild black holes caused by boosts and the presence of a binary companion. A superposition of these two perturbations then yields approximate, but fully analytic binary black hole initial data that are accurate to first order in the inverse of the binary separation and the square of the black holes' momenta. © 2006 The American Physical Society.