Showing 3371 - 3380 of 5713 Items
William Zorach
Date: 1968-01-01
Creator: Christopher Huntington
Access: Open access
- "An exhibition made possible by the Maine State Commission on the Arts and the Humanities, together with the exhibiting institutions ... Coordinator of the exhibition - Christopher Huntington." Catalogue of an exhibition held at the Colby College Art Museum Aug. 14-Sept. 22, 1968; Bowdoin College Museum of Art Nov.1-25, 1968.
Tokyo Nightviews
Date: 1986-01-01
Creator: Yvonne Jacquette
Access: Open access
- Catalogue of an exhibition held Apr. 5-May 3, 1986, at Brooke Alexander, New York, and June 27-Aug. 24, 1986, at Bowdoin College Museum of Art, Brunswick, Maine
Genome-wide single-nucleotide polymorphism map for Candida albicans
Date: 2004-06-01
Creator: Anja Forche, P. T. Magee, B. B. Magee, Georgiana May
Access: Open access
- Single-nucleotide polymorphisms (SNPs) are essential tools for studying a variety of organismal properties and processes, such as recombination, chromosomal dynamics, and genome rearrangement. This paper describes the development of a genome-wide SNP map for Candida albicans to study mitotic recombination and chromosome loss. C. albicans is a diploid yeast which propagates primarily by clonal mitotic division. It is the leading fungal pathogen that causes infections in humans, ranging from mild superficial lesions in healthy individuals to severe, life-threatening diseases in patients with suppressed immune systems. The SNP map contains 150 marker sequences comprising 561 SNPs and 9 insertions-deletions. Of the 561 SNPs, 437 were transition events while 126 were transversion events, yielding a transition-to-transversion ratio of 3:1, as expected for a neutral accumulation of mutations. The average SNP frequency for our data set was 1 SNP per 83 bp. The map has one marker placed every 111 kb, on average, across the 16-Mb genome. For marker sequences located partially or completely within coding regions, most contained one or more nonsynonymous substitutions. Using the SNP markers, we identified a loss of heterozygosity over large chromosomal fragments in strains of C. albicans that are frequently used for gene manipulation experiments. The SNP map will be useful for understanding the role of heterozygosity and genome rearrangement in the response of C. albicans to host environments.
Vulnerability of eelgrass (Zostera marina) to green crab (Carcinus maenas) invasion
Date: 2014-08-01
Creator: Sabine Y Berzins
Access: Open access
- Eelgrass (Zostera marina) is a perennial seagrass that is widely distributed among the shallow subtidal and intertidal Atlantic coastline of the United States and Canada. A highly productive keystone species, eelgrass helps maintain healthy estuarine and ecosystem functions by stabilizing sediments, regulating water flow, absorbing nutrients, and providing critical habitat for animals including commercially important species like soft-shell clams, blue mussels, and migrating waterfowl. Loss of eelgrass beds can therefore result in degraded water quality, shoreline erosion, and reduced fish and wildlife populations. Historically, the Maine coast supported extensive eelgrass beds. However, between 2010 and 2013, eelgrass distribution in Casco Bay declined in area by over 55%. This decline in eelgrass distribution coincides with a regional population explosion of green crabs (Carcinus maenas), an invasive species that physically disturbs eelgrass while foraging for prey. This summer, I collaborated with several Casco Bay Eelgrass Partners including individuals from the Fish and Wildlife Service, Maine Department of Environmental Protection, and the Friends of Casco Bay. Led by U.S. Geological Survey biologist Dr. Hilary Neckles, this project identifies factors that make eelgrass more or less resilient to invasion by green crabs. In June, we established permanent eelgrass survey transects at five locations spanning eastern Casco Bay. Where possible, two transects were established in different types of sediment (fine or coarse/sandy). Most of the eelgrass loss observed over the past decade has been in fine sediments. The question remains; is eelgrass in coarse sediments prone to similar levels of damage? In addition to differences in substrate type, each site also exhibited varying degrees of eelgrass density, shoot height, green crab density and population structure, and other environmental stressors including light availability, temperature, nutrient availability, and natural physical disturbance. I made biweekly measurements of green crab densities at one site, Widgeon Cove in Harpswell. Crap trapping indicated few green crabs occurred near the Widgeon Cove transect, but traps at the other four Casco Bay sites collected as many as 300 crabs within a 24-hour period. Final measurements in the eelgrass transects will be taken in September and data collection will be completed in October. Data gathered this summer will provide information to help move forward with a plan to protect and potentially restore eelgrass in Casco Bay. Additionally, I identified patches of eelgrass in the Kennebec Estuary that might be viable sites for replanting next summer. I hope to continue working on this project next year, thinking about ways to restore eelgrass to the system while identifying ways to increase trapping pressure on green crabs such that their numbers might be reduced. Final Report of research funded by the Rusack Coastal Studies fellowship.
Making predictions in an uncertain world: Environmental structure and cognitive maps
Date: 1999-01-01
Creator: Eric Chown
Access: Open access
- This article examines the relationship between environmental and cognitive structure. One of the key tasks for any agent interacting in the real world is the management of uncertainty; because of this the cognitive structures which interact with real environments, such as would be used in navigation, must effectively cope with the uncertainty inherent in a constantly changing world. Despite this uncertainty, however, real environments usually afford structure that can be effectively exploited by organisms. The article examines environmental characteristics and structures that enable humans to survive and thrive in a wide range of real environments. The relationship between these characteristics and structures, uncertainty, and cognitive structure is explored in the context of PLAN, a proposed model of human cognitive mapping, and R-PLAN, a version of PLAN that has been instantiated on an actual mobile robot. An examination of these models helps to provide insight into environmental characteristics which impact human performance on tasks which require interaction with the world. Copyright 1999 International Society for Adaptive Behavior.
Accelerating change: The power of faculty change agents to promote diversity and inclusive teaching practices
Date: 2019-10-02
Creator: R. Heather Macdonald, Rachel J. Beane, Eric M.D. Baer, Pamela L. Eddy, Norlene R., Emerson, Jan Hodder, Ellen R. Iverson, John R. McDaris, Kristin O’Connell, Carol J. Ormand
Access: Open access
- Faculty play an important role in attracting students to the geosciences, helping them to thrive in geoscience programs, and preparing them for careers. Thus, faculty have the responsibility to work toward broadening participation in the geosciences by implementing equitable and inclusive practices in their teaching and their programs. Faculty professional development that promotes diversity and inclusion is one way to move evidence-based practices into wider use. The adoption of these practices may be accelerated through a professional development diffusion model that amplifies the impacts through the work of faculty change agents. An example of this approach is the SAGE 2YC professional development program, in which faculty change agents learn and practice strategies during workshop sessions, implement changes in their own teaching, and then work in teams to lead workshops in their region under the auspices of the national program. Although this example focuses on two-year colleges, the model is applicable to faculty professional development more broadly. The success of the model is due in large part to a suite of leader-developed workshop sessions and curated resources that change agent teams may select and adapt for the regional workshops they lead. Furthermore, change agents are trusted colleagues, which makes adoption of the evidence-based practices by regional workshop participants more likely. Increased adoption of a change agent approach to faculty development will support the creation and sharing of additional resources, leading to wider diffusion and implementation of inclusive teaching practices.
Reflections questionnaire response by Anonymous on April 1, 2021
Date: 2021-01-01
Creator: Anonymous
Access: Open access
- This is a response to the Documenting Bowdoin & COVID-19 Reflections Questionnaire. The questionnaire was created in March 2021 by staff of Bowdoin's George J. Mitchell Department of Special Collections & Archives. The author is from the class of 2022.
Green Icebergs Revisited
Date: 2019-02-01
Creator: Stephen G. Warren, Collin S. Roesler, Richard E. Brandt, Mark Curran
Access: Open access
- Ice crystals form in supercooled seawater beneath several Antarctic ice shelves; as they rise to the ice-shelf base they scavenge particles from the water and incorporate them into the growing basal ice. The resulting marine ice can be ~100 m thick; it differs from sea ice in that it is clear, desalinated, and bubble-free. Icebergs of marine ice vary in color from blue to green, depending on the nature and abundance of foreign constituents in the seawater that became trapped in the ice as it grew. A red or yellow material (i.e., one that absorbs blue light), in combination with the blue of ice, can shift the wavelength of minimum absorption to green. Previously, dissolved organic carbon (DOC) had been proposed to be responsible for the green color. Subsequent measurements of low DOC values in green icebergs, together with the recent finding of large concentrations of iron in marine ice from the Amery Ice Shelf, suggest that the color of green icebergs is caused more by iron-oxide minerals than by DOC. These icebergs travel great distances from their origin; when they melt they can deliver iron as a nutrient to the Southern Ocean.