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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.
101

Estudo anatômico do cerebelo do macaco Cebus apella / Anatomical study of the cerebellum of the Cebus apella monkey

Oliveira, Wilker Gléria de 20 December 2005 (has links)
O gênero Cebus, representado por quatro espécies e várias subspécies, encontra-se geograficamente distribuído desde a América Central até o sul da América do Sul. Entretanto, sua anatomia é ainda muito pouco conhecida. É de fácil adaptação, podendo sobreviver em pequenas matas e restingas, mas a contínua destruição de seu habitat vem ameaçando, de forma progressiva, sua sobrevivência, o que vem ressaltar a importância de estudos dessa natureza. Considerando-se ainda as importantes funções do cerebelo, no controle e manutenção do equilíbrio corporal e do tono muscular, bem como no estabelecimento da postura e da harmonia e coordenação de movimentos, o presente trabalho tem a proposta de analisar, no C. apella, macro e mesoscopicamente, a disposição das estruturas de seu cerebelo. Com isso, tem-se por objetivo o melhor conhecimento do cerebelo do C. apella, o que nos permitirá tecer ilações a respeito de suas potencialidades funcionais, em comparação a outros primatas não-humanos, a mamíferos domésticos e ao homem. Foram utilizados 20 animais, 16 para analise macroscópica e 4 para mesoscopia, fixados e conservados em formol 10%, pertencentes ao acervo de pesquisa do Prof. Dr. Zenon Silva, na Universidade Federal de Uberlândia, MG. Após conveniente preparo de cada peça, macroscopicamente foram observados os hemisférios cerebelares, que se mostram pouco desenvolvidos em relação ao verme. No corpo do cerebelo, foram identificadas três porções, os lobos anterior, posterior e flóculonodular, assim constituídos, respectivamente: língula, lóbulo central, bastante desenvolvido, assim como suas asas, cúlmen e lóbulo quadrangular anterior; declive, lóbulo, quadrangular posterior, folha do verme, lóbulos semilunares, bem caracterizados na região equatorial dos hemisférios, sendo um superior e um inferior, túber, pirâmide, tonsilas bem desenvolvidas, e lóbulo biventre também bem demarcado. São bem evidentes as fissuras primária (entre os lobos anterior e posterior), horizontal (entre os lóbulos semilunares superior e inferior), secundária (pós-piramidal) e a póstero-lateral (separando o nódulo e a úvula e os hemisférios do lobo floculonodular), intraculminal e pós-clival. Outras fissuras menos evidentes são a pré-central, pré-culminal, pré-piramidal e intra-biventre. Os cortes para análise dos aspectos morfológicos internos, foram efetuados segundo os planos sagital mediano e horizontal, com espessura de 2 a 3 mm, sendo corados pelas soluções de Mulligan. As estruturas evidenciadas são descritas com detalhes comparando-se os dados obtidos com os da literatura consultada. Os termos anatômicos foram referidos segundo a Terminologia Anatômica (Internacional), 1ª. Edição brasileira - 2001, Ed. Manole Ltda. / The gender Cebus, represented by four species and several subspecies, it\'s found geographically distributed since Central America up to the south of South America however, its anatomy is still little well-known. Its from easy adaptation and can survive in small forests and restingas, but the continuous destruction of its habitat has been threatening, in a progressive way, its survival, what point the importance of these kinds of study. Considering still the important cerebellum\'s function at the control and maintenance of body equilibrium and muscle tonus, as well as the estabilishement of posture, harmony and movements coordenating, the present work proposes to analyze, on C. apella, macro and mesoscopically, the disposition of structures at its cerebellum. This way the objective is to know better C. apella\'s cerebellum, what will allow us to weave related to its functional potentialities comparing to other no-human primates, domestic mammals and human. Its was used 20 animals, 16 to macroscopic analysis and 4 mesoscopic fixed and kept in of formaldehyde 10%, belonging to the research of Professor Dr. Zenon Silva, at Universidade Federal de Uberlândia, MG. After convenient prepare of each part, it was macroscopically observed the cerebellum hemispheres that seems little developed in relation to the worm. At cerebellum\'s body, it was identified three portions, the previous lobe, posterior and floculonodular, like this respectively constituted: língula, central lobule plenty developed, as well as its wings, cúlmen and previous quadrangular lobule, declive, posterior quadrangular lobule, worm\'s leaf, semilunar lobules well characterized at equatorial region of the hemispheres, being one above and one below, túber, pyramid, well developed tonsil and biventer lobule also well demarcated. Its very obvious the primary fissure (between the previous and posterior lobe), horizontal (between the superior and inferior lóbules semilunar) secundary (post-pyramidal) and the posterolateral (separating the nodule and the uvula and the hemisphere of lobe floculonodular), intraculminal and post-clival. Other less obvious fissures are the pré-central, pré-culminal and intra-biventer. The cuts to morfological internal analysis were effected according to the average and horizontal sagittal plans, with tickness from 2 to 3 mm, being colours by muligan\'s solutions. The obvious structures are described with details comparing the data obtained with the researched literature. The anatomic terms were refered according to the Anatomic Terminology (International), first Brazilian edition- 2001, Ed. Manole Ltda.
102

Avaliação de diluidores à base de gema de ovo e de lecitina de soja para a congelação de sêmen de Alouatta caraya /

Carvalho, Fernanda Maria de. January 2012 (has links)
Orientador: Jose Mauricio Barbanti Duarte / Coorientador: Rodrigo del Rio do Valle / Banca: Paulo Henrique Franceschini / Banca: Marcílio Nichi / Resumo: As alterações constantes do meio ambiente com diminuição do habitat natural dos primatas brasileiros têm estimulado o desenvolvimento de biotecnologias na área da reprodução, visando à preservação de espécies. Este estudo teve por objetivo avaliar, pela primeira vez, técnicas de criopreservação de sêmen de Alouatta caraya. Foram colhidas 26 amostras de sêmen de seis Alouatta caraya machos adultos e sadios, mantidos em cativeiro no Centro Nacional de Primatas (CENP), Ananindeua, PA. As amostras foram analisadas imediatamente após a colheita quanto aos parâmetros volume, pH, concentração, motilidade total e progressiva, integridade de membrana plasmática, integridade de acrossoma, atividade citoquímica mitocondrial, estresse oxidativo (TBARS) e fragmentação de DNA (SCSA). Após as análises iniciais, as amostras foram congeladas com quatro diluidores diferentes - Test-gema de ovo com glicerol 3 ou 4% e Test-lecitina de soja com glicerol 3 ou 4%, utilizando máquina de congelação automática TK 3000. As amostras foram descongeladas e analisadas aos 10, 40 e 80 minutos pós-descongelação. Diluidores à base de gema de ovo foram mais adequados para congelação de sêmen dessa espécie, quando comparados aos diluidores à base de lecitina de soja. Não houve diferença estatística quanto à concentração de glicerol, porém para o diluidor à base de gema de ovo, a concentração de 4% apresentou melhores resultados. Este trabalho trouxe informações inéditas a respeito de características seminais e aspectos da criopreservação de sêmen dessa espécie, todavia os protocolos de congelação testados não foram considerados adequados para a preservação das amostras estudadas / Abstract: The constant environmental changes with reduction of the natural habitat of the Brazilian primates require the development of assisted reproductive techniques (ARTs) for species conservation. The objective of this study was to evaluate, for the first time, cryopreservation techniques for Alouatta caraya semen. Twenty-six semen samples were collected from six captive adult Alouatta caraya from the National Primate Center, Ananindeua, PA - Brazil. Samples were analyzed immediately after collection for the following parameters: volume, pH, concentration, total and progressive motility, plasma membrane integrity, acrosome integrity, oxidative stress (TBARS), and DNA fragmentation (SCSA). After initial evaluation, samples were frozen in four different extenders - Test-egg yolk with 3 or 4% glycerol and Test-soy lecithin with 3 or 4% glycerol - using an automatic freezer TK 3000. Samples were thawed and analyzed for the same parameters at 10, 40 and 80 minutes post-thaw. Egg yolk-based extenders seemed better for cryopreservation of semen from this species when compared to soy lecithin-based extenders. Although there was no statistical difference between the different glycerol concentrations, for the egg yolk-based extenders, 4% glycerol had better results. This study brought novel information on semen characteristics and cryopreservation aspects for this species, although the protocols tested were not considered suitable for the cryopreservation of the samples studied / Mestre
103

The female's role in primate socio-sexual communication: a study of the vervet monkey (Cercopithecus adthiops pygarthrus) and the Chacma baboon (Papio ursimus)

Girolami, Letizia 05 February 2015 (has links)
A thesis submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, infulfilment of the requirements for the .degree Doctor of Philosophy Johannesburg ' 1989
104

Affective Responses to Inequity in Capuchin Monkeys

Fernandez, Danny 06 May 2012 (has links)
Many studies have documented adverse affects to inequitable situations in non-human primates. The behaviors that have predominantly been examined include food taking, collecting, giving, and refusals between the primate subjects and the experimenters. However, no studies had looked at the affective responses to inequity in primates. In a recent study, four-year old children who were rewarded inequitably accepted the reward, however they showed affective signs of dissatisfaction. For this study, we looked for affective displays in capuchins during inequitable exchange tasks. We predicted that the capuchins that were experiencing inequity would show more signs of agitation and aggression than those in equitable situations. We saw no increase in agitation or aggression when subjects were treated inequitably. There was higher aggression towards partners who received the lower reward in inequitable situations and less agitation seen by partners during frustration controls. Future studies may find our hypothesized results using different methodologies.
105

An Analogical Paradox for Nonhuman Primates: Bridging the Perceptual-Conceptual Gap

Flemming, Timothy M. 14 July 2010 (has links)
Over the past few decades, the dominant view by comparative psychologists of analogical reasoning in nonhuman primates was one of dichotomy between apes, including humans, and monkeys: the distinction between the analogical ape and paleological monkey (Thompson & Oden, 2000). Whereas evidence for analogy proper by representation reinterpretation in monkeys is sparse and debated, the gap between that which is analogic and paleologic has been narrowed by the studies presented here. Representation of relational concepts important for analogy proves difficult for rhesus and capuchin monkeys without the ability to rely on a greater amount of perceptual variability, implicating a perceptually-bound predisposition in problem-solving (Chapters 2-3). A shift in attention from perceptual features to abstract concepts for employment in relational matching is again difficult, but not impossible given cognitive incentive in the form of differential outcomes to refocus attention on conceptual properties (Chapter 4). Finally, chimpanzees unlike monkeys appear more apt to reason by analogy, perhaps due to a more default conceptual focus (Chapter 5). Taken together, these studies provide an account for the emergence of analogical reasoning skills throughout the primate lineage in contrast to views regarding analogy a hallmark of human intelligence.
106

Numerical Cognition in Rhesus Monkeys (Macaca mulatta)

Marr, Emily Harris 15 July 2008 (has links)
Over the past few decades, researchers have firmly established that a wide range of nonhuman animals exhibit some form of numerical competence. The focus of this research was to define further the extent of numerical ability in rhesus monkeys, and specifically to determine whether the animals possess a symbolic understanding of Arabic numerals. This required examining the stimulus attributes (e.g., number vs. hedonic value) represented by the numerals, as well as the precision (e.g., absolute vs. relative) and generality of those representations. In chapters 2 and 3, monkeys were required to compare and order numerals and were rewarded with either proportional or probabilistic rewards. The results indicated that monkeys were relying on the ordinal or absolute numerical values associated with each numeral and not hedonic value or learned 2-choice discriminations. The studies in chapters 4 and 5 indicated that monkeys can use numerals to symbolize an approximate number of sequential motor responses. The study in Chapter 6 tested the generality of the monkeys’ symbolic number concept using transfer tests. The results indicated that some monkeys are able to abstract number across presentation mode, but this ability is only exhibited under limited conditions. Collectively, these studies provide evidence that rhesus monkeys view Arabic numerals as more than sign-stimuli associated with specific response-reward histories, but that numerals do not have the same precise symbolic meaning as they do for humans.
107

EFFECTS OF DELTA-9#-TETRAHYDROCANNABINOL ON SQUIRREL MONKEY INCENTIVE COMPETITION BEHAVIOR

Jones, Byron Clarence, 1944- January 1975 (has links)
No description available.
108

The learning of patterned strings problems by squirrel monkeys

Cha, Jae-Ho, 1934- January 1967 (has links)
No description available.
109

Social behavior and dominance relations in squirrel monkeys during competitive pairwise and triad situations

Meyer, Marilyn Wooley, 1951- January 1975 (has links)
No description available.
110

Effect of contiguity between stimulus and reinforcer on speed of acquisition and transfer of learning-set in squirrel monkeys

Smith, Harriet Jane, 1951- January 1975 (has links)
No description available.

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