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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

GENETIC ANALYSIS AND EVOLUTIONARY HISTORY OF THE LOMAMI RIVER BLUE MONKEY, CERCOPITHECUS MITIS HEYMANSI, IN THE CENTRAL CONGO BASIN

Unknown Date (has links)
Cercopithecus mitis is a polytypic, pan-African guenon species with a complex evolutionary history. The Lomami River Blue Monkey, C. m. heymansi, occurs within the Tshuapa-Lomami-Lualaba (TL2) Conservation Landscape and exhibits high pelage variation. Previous studies have shown discordance between the mitochondrial and Ychromosome gene trees of C. m. heymansi. The objectives were to test the phylogenetic pattern found in the mtDNA tree using a larger sample size of C. m. heymansi, determine the genetic diversity of the population, and hypothesize methods of speciation. While many species within the C. mitis radiation depict paraphyly, I determined that C. m. heymansi forms highly supported monophyletic clades in both mtDNA and Ychromosome gene trees. These results suggest that C. m. heymansi is a distinct lineage within the C. mitis radiation. Future genomic analyses are important in resolving the evolutionary history of this population and discerning its taxonomic classification and conservation value. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection
132

Contributions of the hippocampus and related ventromedial temporal cortices to memory in the rhesus monkey

Beason-Held, Lori L. January 1994 (has links)
Thesis (Ph.D.)--Boston University / PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. / While memory function in primates depends on the integrity of the medial temporal lobe, the contribution of the hippocampal formation (HF) independent of the overlying ventromedial temporal cortices, particularly the entorhinal (ENT) and parahippocampal (PHG) cortices, remains unclear. To address this issue we have prepared groups of rhesus monkeys with ibotenic acid lesions of the HF or aspiration lesions of the ENT or PHG cortices. We then administered behavioral tasks to assess the effects of these lesions relative to normal controls. To test recognition memory, the Delayed Non-Matching to Sample (DNMS) task and the Delayed Recognition Span Task (DRST) were administered. On DNMS, all groups were impaired on both acquisition and 2 and 10 minute delays. The DRST, administered in Spatial, Color and Object conditions, yielded slightly different results. On the Spatial condition, all groups were impaired on both unique and repeated trials of the task. On the Color condition, all groups were impaired on unique trials while only the HF group was impaired on repeated trials. On the Object condition, ENT and PHG groups were only impaired on unique trials, while the HF group was unimpaired. To assess associative memory, two choice reversals were administered in Spatial (SR) and Object (OR) modalities. On the SR task, The HF group was impaired on acquisition and the first of three reversal phases. The ENT group was impaired on all three reversals, and the PHG group was impaired on only the last. On the OR task, HF animals were impaired on all reversals, while ENT animals were impaired on the initial reversal and PHG animals on the last two. These results indicate that damage to the HF alone causes impairments in recognition, spatial processing and object reversal learning. They also indicate that ENT and PHG regions make unique contributions to memory processes as seen in additional impairments on DRST and the inability to perform spatial reversals. Thus impairments previously attributed to hippocampal damage in studies where the ENT and PHG cortices were removed in conjunction with the HF need to be reevaluated in view of additional contributions provided by these cortical regions. / 2031-01-01
133

Flexible routing of information for decision making

Odean, Naomi N. January 2020 (has links)
Behaving in a complex world requires flexible mapping between sensory inputs and motor outputs. One must be able to make decisions about what actions to take based on a wide variety of inputs. This presents a routing problem: brain areas involved in decision making must receive information encoded by different sensory neurons in different situations. In this thesis I investigate this routing problem using two variations of the random dot motion task which require flexible routing. In the first, a single random dot motion task appears in different locations on different trials. Recording from the lateral intraparietal area (LIP) revealed several neural features which varied with stimulus location. A second task made it possible to disentangle routing from other signals, by separating the time of routing from the onset of motion and decision making. In this second task, a visual cue indicated the location at which relevant motion would appear. After the cue was extinguished, two random dot motion patches appeared. An informative patch appeared at the cued location, and an uninformative patch appeared at another location. Comparison of these two tasks revealed three location dependent signals at motion onset: a visual signal related to surround suppression, a second suppressive signal that may set the amount of evidence required for decision making, and a 12-20 hertz oscillation in firing rate. This oscillation appears to be a signature of flexible information routing. It appears at motion onset when the motion stimulus varies in location unpredictably; it appears at cue onset when a spatial cue indicates the location information must be routed from; and it does not appear when stimulus location is fixed and flexible routing is not required. Future work on this project will eventually require tools which are not well developed for use in rhesus macaques. The final chapter describes two projects which attempt to address this problem, one through the use of optogenetics in monkeys and the other by adapting an established monkey behavioral task for use in mice.
134

Auditory stimulation and control as sources of environmental enrichment for captive Rhesus monkeys.

Drewsen, Karla Hull 01 January 1985 (has links) (PDF)
No description available.
135

Evaluation of sperm functionality in non-human primates, focussing on sperm capacitation

Mabotha, Luke Allen January 2019 (has links)
Magister Scientiae (Medical Bioscience) - MSc(MBS) / The incidence of male infertility is increasing, with up to 50% of infertile males having “unexplained” (idiopathic) infertility. Newly developed molecular techniques have great value in detecting subtle causes of male infertility, as compared to idiopathic infertility which may be explained by standardizing and optimizing sperm functional and structural tests in non-human primate (NHP) sperm. The aim of the study was to evaluate sperm functionality utilizing the sperm of two NHP species, i.e.1) the rhesus monkey (Macaca mulatta) and 2) the vervet monkey (Chlorocebus aethiops), and further evaluate the effect of physiological media (including commonly used, and newly formulated sperm wash and sperm capacitating media) on NHP sperm functionality. Sperm functionality was evaluated by investigating the following sperm functions i.e.: sperm motility, vitality, acrosome reaction (AR), hyperactivation, and mitochondrial membrane potential (MMP). Sperm functional tests included computer-aided semen analysis (CASA), motility analysis, BrightVit staining for sperm vitality, flourescenin isothiocyanate (FITC)- conjugated peanut agglutinin (PNA) staining for sperm acrosome integrity, induction of hyperactivation by stimulants (sperm preparation media containing capacitating ingredients), and mitochondrial inhibitor (Oligomycin-A) for testing MMP. All functional and structural tests were investigated in both species, except for acrosome integrity, mitochondrial inhibition and functional tests compared over time that could not be successfully completed and investigated in the rhesus species. Motility analysis tests proved that within the vervet species, the use of different physiological media results in statistically significant differences in motility and kinematic parameters over a 1 hour time period. Hyperactivation tests proved that capacitating physiological media produced significantly higher percentages hyperactivation when compared to sperm wash media within the vervet species over a 1 hour time period. Furthermore, within both NHP species, sperm structural analysis (vitality and acrosome integrity) results showed that no significant differences are present when making use of different physiological media over a period of 1 hour incubation. The incubation of vervet sperm with different concentrations of mitochondrial inhibitor, Oligomycin-A (0 μM, 5 μM, and 25 μM), resulted in motility inhibition over a 1 hour incubation period. By the evaluation of these tests it was found that the use of different sperm wash [Human tubal fluid (HTF), Ham‟s F-10® and HD Sperm Wash Plus (HDSWP)] and sperm capacitation media [Human tubal fluid with added caffeine (HTFC) and HD Sperm Capacitating Plus (HDSCP)] resulted in significantly different results within sperm functional tests as compared to sperm structural tests. The study indicates that the composition of media, varying from simple to more complex, used for semen preparation plays an important role in determining NHP sperm functionality. Based on these findings further investigation in larger NHP sample groups and human sperm are required to evaluate the role of certain ingredients in the development of more cost-effective media producing satisfactory results in terms of sperm functionality for artificial reproductive technologies (ART).
136

Dental Microwear Analysis of Cercopithecoides Williamsi

Geissler, Elise 08 April 2013 (has links)
Cercopithecoides williamsi, a Plio-Pleistocene primate, is believed to have been a terrestrial colobine monkey. Dental microwear analysis of C. williamsi specimens from South African cave sites was employed to test these assumptions. Analysis of the features shows that although the microwear signature of C. williamsi is similar to that of folivorous primates, there are also similarities with terrestrial papionins. Overall, the dental microwear analysis demonstrates that C. williamsi could have indeed been a folivorous, terrestrial monkey. A high amount of puncture pits also points to a substantial amount of grit in the diet. Similarities between the microwear features of C. williamsi and Cebus apella indicate that fruit or hard objects could have been a supplemental food of C. williamsi. The consumption of underground storage organs covered in grit would explain the heavy pitting of C. williamsi teeth. Being terrestrial, C. williamsi would have been in direct competition with terrestrial papionins.
137

The roles of norepinephrine and neuropeptide Y in the control of the onset of puberty in female rhesus monkeys

Gore, Andrea C., January 1990 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1990. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 107-128).
138

Foraging ecology of the vervet monkey (chlorocebus aethiops) in mixed lowveld bushveld and sour lowveld bushveld of the blydeberg conservancy, Northern Province, South Africa

Barrett, Alan Sean 31 October 2005 (has links)
Vervet Monkeys (Chlorocebus aethiops) are versatile primates of the suborder HAPLORHINI, family CERCOPITHECIDAE, subfamily CERCOPITHECINAE, and genus Chlorocebus (Skinner & Smithers, 1990). They are a widely distributed species that adapt easily to a variety of environments, occurring throughout the Northern and Southern Savanna, from Senegal to Sudan and south to the tip of Southern Africa (Estes, 1992). According to Estes (1992), vervets are opportunistic omnivores. being predominantly vegetarians that live on wild fruits, flowers, leaves, buds, seeds, pods, sap, roots and tubers. Occasionally they will feed on invertebrates (grubs, termites, grasshoppers) and vertebrates (bird and reptile eggs and chicks) (Skinner & Smithers, 1990). Not much ecological research has been done on vervets outside the tropics to date, and it was thus considered necessary to determine how vervets cope with the effects of temperate area seasonality. The aim of this study was to describe the habitat structure of a vervet monkey troop's territory and then to investigate the effects of seasonality on differences in their diet (both overall and with respect to sex differences). activity patterns and habitat utilisation. / Agriculture Animal Health and Human Ecology / M.Tech. (Nature Conservation)
139

Foraging ecology of the vervet monkey (chlorocebus aethiops) in mixed lowveld bushveld and sour lowveld bushveld of the blydeberg conservancy, Northern Province, South Africa

Barrett, Alan Sean 31 October 2005 (has links)
Vervet Monkeys (Chlorocebus aethiops) are versatile primates of the suborder HAPLORHINI, family CERCOPITHECIDAE, subfamily CERCOPITHECINAE, and genus Chlorocebus (Skinner & Smithers, 1990). They are a widely distributed species that adapt easily to a variety of environments, occurring throughout the Northern and Southern Savanna, from Senegal to Sudan and south to the tip of Southern Africa (Estes, 1992). According to Estes (1992), vervets are opportunistic omnivores. being predominantly vegetarians that live on wild fruits, flowers, leaves, buds, seeds, pods, sap, roots and tubers. Occasionally they will feed on invertebrates (grubs, termites, grasshoppers) and vertebrates (bird and reptile eggs and chicks) (Skinner & Smithers, 1990). Not much ecological research has been done on vervets outside the tropics to date, and it was thus considered necessary to determine how vervets cope with the effects of temperate area seasonality. The aim of this study was to describe the habitat structure of a vervet monkey troop's territory and then to investigate the effects of seasonality on differences in their diet (both overall and with respect to sex differences). activity patterns and habitat utilisation. / Agriculture Animal Health and Human Ecology / M.Tech. (Nature Conservation)
140

Reproductive aging & long-term hormone replacement therapy in the rhesus macaque

Naugle, Michelle Marie 22 September 2014 (has links)
Menopause is a natural transition heralded by the cessation of menstrual cycles and ovulation, and it occurs in all women at an average of about 50 years of age. While not a disease, menopause is often accompanied by symptoms that interfere with the quality of life and these symptoms are due to the relatively abrupt deprivation of E2 and P4 experienced during reproductive aging. Reproductive aging consists of changes in the synthesis and release of hormones from the hypothalamus, pituitary and gonad, which make up the HPG axis. Because gonadal hormones play critical roles in many systems throughout the body and brain, not just reproduction, treatment of menopausal symptoms to date largely involves hormone replacement therapy (HRT) with E2, P4 or their combination. While not intended to treat other neurobiological symptoms beyond hot flushes, HRT has the potential to exert widespread actions due to the abundance of hormone receptors throughout the nervous system. Thus, a fuller understanding of the neurobiology of menopause is badly needed. Although much of the research into the mechanisms that underlie reproductive aging focuses on ovarian failure and follicular atresia (cell death), there is evidence that there are significant alterations in the function of the neuroendocrine levels - the hypothalamus and pituitary - that also contribute to this process. As the mean age of the population increases, the number of post-menopausal women continues to grow with broad economic, healthcare and social costs. It is increasingly important to understand the complex mechanisms underlying reproductive aging and the effects of HRT. In this dissertation, I focus on the question of how the female non-human primate hypothalamus changes both with aging and in response to steroid hormone treatments. / text

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