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An open source syringe pump controller for fluid delivery of multiple volumes
No full textAuthor manuscript. Published in final form in: eNuero, Vol. 6, Issue 5, ENEURO.0240-19.2019.Syringe pumps are a necessary piece of laboratory equipment that are used for fluid delivery in behavioral neuroscience laboratories. Many experiments provide rodents and primates with fluid rewards such as juice, water, or liquid sucrose. Current commercialized syringe pumps are not customizable and do not have the ability to deliver multiple volumes of fluid based on different inputs to the pump. Additionally, many syringe pumps are expensive and cannot be used in experiments with paired neurophysiological recordings due to electrical noise. We developed an open source syringe pump controller using commonly available parts. The controller adjusts the acceleration and speed of the motor to deliver three different volumes of fluid reward within one common time epoch. This syringe pump controller is cost effective and has been successfully implemented in rodent behavioral experiments with paired neurophysiological recordings in the rat frontal cortex while rats lick for different volumes of liquid sucrose rewards. Our syringe pump controller will enable new experiments to address the potential confound of temporal information in studies of reward signaling by fluid magnitude
Nutritional associations among fauna at hydrocarbon seep communities in the Gulf of Mexico
No full textPublished in: Marine Ecology Progress Series, 2005, Vol. 292, pp. 51-60.The Gulf of Mexico supports dense aggregations of megafauna associated with hydro-
carbon seeps on the Louisiana Slope. The visually dominant megafauna at the seeps — mussels and
tube worms — derive their nutrition from symbiotic relationships with sulfide or methane-oxidizing
bacteria. The structure of the tube worm aggregations provide biogenic habitat for numerous species
of heterotrophic animals. Carbon, nitrogen and sulfur stable isotope analyses of heterotrophic fauna
collected with tube worm aggregations in the Green Canyon Lease area (GC 185) indicate that most
of these species derive the bulk of their nutrition from chemoautolithotrophic sources. The isotope
analyses also indicate that although 2 species may be deriving significant nutritional input from the
bivalves, none of the species analyzed were feeding directly on the tube worms. Grazing gastropods
and deposit-feeding sipunculids were used to estimate the isotopic value of the free-living chemoau-
tolithotrophic bacteria associated with the tube worms (δ13C –32 to –20‰; δ15N 0 to 7‰; δ34S –14 to
–1‰). The use of tissue δ34S analyses in conjunction with tissue δ13C and δ15N led to several insights
into the trophic biology of the communities that would not have been evident from tissue stable C and
N analyses alone
Creating a New Cultural Unity: Images of Pre-Columbian Mexico in the Artwork of Diego Rivera and Frida Kahlo
No full textResearch paper submitted to American University in partial fulfillment of the Degree of Master of Arts; approved as non-thesis optio
Records of a Woman's Inner Conflict; Marie Bracquemond's Paintings of Women in Her Garden
No full textResearch paper submitted to American University in partial fulfillment of the Degree of Master of Arts; approved as non-thesis optio
Marcel Duchamp and/as Arose Selavy: Gender and the Ideological Conditions of Art after World War I
No full textResearch paper submitted to American University in partial fulfillment of the Degree of Master of Arts; approved as thesis optio
The effects of conditioned taste aversions on the acquisition and maintenance of schedule-induced polydipsia
No full textPublished in: Animal Learning & Behavior, 1979, 7 (1), 3-12.Conditioned taste aversions produced a moderate, but transient, suppression of schedule-
induced polydipsia. This suppression was greater and longer lasting when rats were offered
a choice between water and the previously poisoned solution on the polydipsia baseline. A
final experiment demonstrated that taste aversions were more effective in suppressing schedule-
induced consumption when superimposed on a developing schedule-induced drinking baseline
as opposed to a stable pattern of schedule-induced drinking. It was suggested that schedule-
induced polydipsia is insensitive to conditioned taste aversions. This conclusion was discussed
in terms of schedule-induced alcohol consumption and its potential as an animal model of
alcoholism
The effect of morphine preexposure on the acquisition of morphine-induced taste aversions: A nonassociative effect
No full textPublished in: Animal Learning & Behavior, 1984, 12 (2), 157-162.In Experiment 1, the amount of time rats spent engaged in a range of behaviors was recorded
immediately prior to and following the intraperitoneal administration of morphine sulfate
(6 mglkg) or distilled water. No behavioral differences were observed between these groups. In
Experiment 2, preexposure to this low dose of morphine attenuated the subsequent acquisition
of a morphine-induced taste aversion independent of the similarity of the preexposure and con-
ditioning environments. These results with a dose of morphine that does not produce any be-
havioral effects, which in turn could potentially mask associative conditioning during preex-
posure, confirm that the attenuating effects of morphine preexposure on taste aversion learning
are nonassociative
Like chimpanzees (Pan troglodytes), pigeons (Columba livia domestica) match and Nash equilibrate where humans (Homo sapiens) do not
No full textAuthor manuscript. Published in final form in: J Comp Psychol., 2019 May, 133(2), 197-206.Martin, Bhui, Bossaerts, Matsuzawa, and Camerer (2014) found that chimpanzee pairs competing in matching-pennies games achieved the Nash equilibrium whereas human pairs did not. They hypothesized this outcome may be due to (a) chimpanzee ecology producing evolutionary changes that give them a cognitive advantage over humans in these games, and (b) humans being disadvantaged because the cognition necessary for optimal game play was traded off in evolution to support language. We provide data relevant to their hypotheses by exposing pairs of pigeons to the same games. Pigeons also achieved the Nash equilibrium, but did so while also conforming with the matching law prediction on concurrent schedules where choice ratios covary with reinforcer ratios. The cumulative effects model, which produces matching on concurrent schedules, also achieved the Nash equilibrium when it was simulated on matching-pennies games. The empirical and simulated compatibility between matching law and Nash equilibrium predictions can be explained in two ways. Choice to concurrent schedules, where matching obtains, and choice in game play, where the Nash equilibrium is achieved, may reflect the operation of a common process in choice (e.g., reinforcer maximization) for which matching and achieving the Nash equilibrium are derivative. Alternatively, if matching in choice is innate as some accounts argue, then achieving the Nash equilibrium may be an epiphenomenon of matching. Regardless, the wide species generality of matching relations in nonhuman choice suggests game play in chimpanzees would not prove advantaged relative to most species in the animal kingdom
Project Tahoga: an exploration of the environment and sustainability of the greater Washington, D.C., region
No full textThis book was written as a way to discover and investigate the environment and
sustainable development of the Greater Washington, D.C. region. The purpose was to
expand and deepen each student’s understanding of environmental science and its
relevance to today’s issues, including its economic and social aspects. The book was
written as a collaborative effort by students at American University for the course titled
Senior Capstone in Environmental Studies. Each of thirteen students contributed one
chapter of this book, and sections such as the Introduction and Conclusion were written
collectively by small groups of students in the class
Portrait of Marie-Antoinette - An Analysis of Identity Construction, Presentation and Reception
No full textResearch paper submitted to American University in partial fulfillment of the Degree of Master of Arts; approved as non-thesis optio