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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.
41

Sistemática de Pyrgotidae do Novo Mundo (Diptera, Schizophora) / Sistematic of Pyrgotidae of the New World (Diptera, Schizophora)

Ramon José Correa Luciano de Mello 01 July 2011 (has links)
Neste trabalho, é apresentada a revisão taxonômica dos Pyrgotidae pertencentes à fauna do Novo Mundo, atualmente composta por 66 nomes válidos de espécies distribuídas em 15 gêneros. A revisão taxonômica resultou na descrição de dois novos gêneros e de duas novas espécies e na sinonímia de quatro gêneros e 18 espécies e uma espécie foi revalidada. De acordo com esses resultados a fauna de Pyrgotidae do Novo Mundo possui 51 espécies válidas dispostas em 12 gêneros. Análises filogenéticas foram processadas com o intuito de testar o monofiletismo dos gêneros e estabelecer o relacionamento entre suas espécies, além de testar o desempenho dos caracteres contínuos na filogenia de Pyrgotidae. Com este propósito foram levantados 54 caracteres morfológicos dos adultos, sendo 14 contínuos e 40 discretos. Os caracteres contínuos e discretos foram analisados separadamente e em evidência total. As análises em que se utilizaram apenas caracteres discretos e as que utilizaram os caracteres em evidência total, resultaram em topologias muito semelhantes entre si, divergindo apenas nas posições entre três terminais. Na topologia obtida em evidência total, o suporte dos ramos aumentou na maioria dos ramos o que demonstra que os caracteres contínuos são filogeneticamente informativos para serem utilizados em Pyrgotidae. / This work presents a taxonomic revision of New World Pyrgotidae, currently composed of 66 valid species names distributed in 15 genera. The taxonomic revision resulted in the description of two new genera and two species, synonymy of four genera and 18 species and revalidation of 1 species. According to these results, the Pyrgotidae of the New World contains 51 valid species arranged in 12 genera. Phylogenetic analyses were conducted to test the monophyly of the genera, establish the relationships among their species, and test the performance of continuous characters in the phylogeny of Pyrgotidae. Fifty-four morphological characters of adults were coded and divided as: 14 continuous and 40 discrete. Continuous and discrete characters were analyzed separately and under total evidence. The analyses using only discrete characters and in total evidence each resulted in one tree, which were very similar, diverging only in the positions of three terminals. In the tree obtained using total evidence, the branch support increased in more branches, which demonstrates that continuous characters are phylogenetically informative for use in analyses of the Pyrgotidae.
42

Estudo genético dos pigmentos visuais em primatas do Novo Mundo / Genetic study of visual pigments in the New World monkeys

Viviani Mantovani Amador 22 February 2016 (has links)
A visão de cores em vertebrados necessita de pelo menos duas classes de cones, (fotorreceptores presentes na retina) e a existência de um substrato neural para que os fótons de luz sejam comparados, processados e posteriormente resultar na sensação da cor. Primatas do Velho Mundo, incluindo humanos, apresentam visão de cor tricromata, enquanto que primatas do Novo Mundo apresentam um polimorfismo nos genes dos pigmentos visuais e, entre os primatas, são os únicos que podem apresentar indivíduos com visão dicromata ou tricromata. O polimorfismo encontrado em primatas do Novo Mundo ocorre devido à variabilidade dos genes que expressam as opsinas responsáveis por absorver comprimentos de onda médios ou longos. Os estudos genéticos das opsinas são essenciais para compreensão do processamento e da sensação de cores nesses animais, e podem ajudar a entender a evolução da visão de cores nos Primatas. O objetivo deste trabalho é caracterizar a diversidade dos pigmentos visuais (LWS/MWS e SWS1) das espécies de primatas do Novo Mundo através de análises genéticas e descrever a sequência de aminoácidos observados para estimar o pico de sensibilidade espectral das opsinas. Foram coletadas amostras de sangue, fezes e/ou pelo de seis gêneros de primatas provenientes de diferentes regiões do Brasil (Pará, Rio de Janeiro, Rio Grande do Norte e São Paulo) e pertencentes às espécies Cebus apella, Callithrix jacchus, Alouatta clamitans, Alouatta caraya, Lagothrix lagothricha, Ateles belzebuth e Brachyteles arachnoides e posteriormente foram analisados os genes que expressam as opsinas nesses indivíduos. As sequências de aminoácidos encontradas nas posições importantes do gene SWS1 (52, 86, 93, 114 e 118) foram diferentes para algumas espécies. No gene SWS1 as espécies C. apella, L. lagotricha, A. belzebuth e B. arachnoides apresentam a sequência de aminoácidos LLPAT e as espécies C. jacchus, A. caraya e A. clamitans apresentaram a sequência de aminoácidos LLPGT. Foi descoberto que variações de aminoácidos na posição 50 do gene SWS1 em primatas do Novo Mundo podem ser importantes na determinação do pico de absorção espectral dos pigmentos expressos por este gene. Os genes LWS e MWS de indivíduos da espécie C. jacchus foram estudados e os aminoácidos localizados nas posições 180, 277 e 285 das opsinas foram identificados. Os resultados dos alelos encontrados nesses grupos tiveram cinco combinações diferentes (SFT, SYA, SYT, AYA e AYT), os alelos AYA e SYA foram descritos pela primeira vez neste grupo e a partir do resultado genético foi inferido o pico de absorção espectral da opsina. Este trabalho preencheu algumas lacunas da bibliografia e trouxe novas informações a respeito da diversidade genética dos pigmentos visuais em primatas do Novo Mundo / Color vision in vertebrates requires the presence of at least two different classes of cones in the retina, and a neural substrate capable to compare the activation of the different photoreceptors, which ultimately leads to color perception. Old World Monkeys (OWM), including humans, have trichromatic color vision, whereas New World Monkeys (NWM) have visual pigment genes polymorphism and among primates, are the only group with dichromatic or trichromatic individuals in the same species. This polymorphism in NWM occurs due to the variability of genes that express the opsins responsible for absorbing medium or long wavelengths. The genetic studies of color vision are fundamental for the comprehension of color perception in these animals and it could help to understand the color vision evolution in Primates. The aim of this work is to characterize the visual pigment diversity (LWS/MWS and SWS1) in NWM species by genetic analysis and estimate the opsin spectral absorption peak, based on the amino acid sequence. Blood, feces and hair were collected from six primate genres from different regions of Brazil (Pará, Rio de Janeiro, Rio Grande do Norte and São Paulo): Cebus apella, Callithrix jacchus, Alouatta clamitans, Alouatta caraya, Lagothrix lagothricha, Ateles belzebuth and Brachyteles arachnoides. The amino acid sequences found in important positions of the SWS1 gene (52, 86, 93, 114 and 118) were different among some species. In C. apella, L. lagotricha, A. belzebuth and B. arachnoides was found the amino acid sequence LLPAT. In C. jacchus, A. caraya and A. clamitans the amino acid sequence was LLPGT. It was observed in previous studies that residue 50 of the SWS1 gene in the New World primates is important to determining the spectral absorption peak of the visual pigments expressed by this gene. The LWS and MWS genes of C. jacchus have been studied and the amino acids located at positions 180, 277 and 285 have been identified. Five different combinations were found among the individuals analyzed: SFT, SYA, SYT, AYA and AYT. Two alleles, AYA and SYA, were described for the first time in this species. The present study filled some gaps in the literature and brought new information on the genetic diversity of visual pigments in New World primates
43

Finanční analýza společnosti New World Resources Plc / Financial analysis of the company New World Resources Plc

Valík, Lukáš January 2013 (has links)
This diploma thesis titled "Financial analysis of the company New World Resources Plc" is structured into three main parts. The first chapter lays down the theoretical framework of the financial analysis including the definitions of the fundamental terms, introduces the main groups of users and presents mostly applied tools. The second part aims to present relevant information about the NWR group, i.e. among others the major shareholders and controlled subsidiaries. Moreover, the substantial part of the chapter dedicates to the market development and recent news and problems related to the company. The key third part, in the help of the tools of the financial analysis, intends to interpret the causes and reasons of the development of the corporate finance of the company. The objective of the final chapter is to determine the extent of the financial health of the enterprise as well as potential risks of its future outlook.
44

The Peopling of the Bahamas: A Phylogeographical Perspective

Simms, Tanya M. 30 March 2011 (has links)
During the past 500 years, the Bahamas has been influenced by a wide array of settlers, including but not limited to, the Arawak Indians, Eleutherian Adventurers, British Loyalists, Creole slaves, liberated Africans as well as Chinese, Greek, Jewish, Lebanese, Jamaican and Haitian migrants. To date, however, only a few reports analyzing the genetic makeup and population dynamics of the Bahamas have been published, making this work pivotal in the endeavor to ascertain the genetic ancestry of these groups. As such, the current investigation was undertaken to genetically characterize six of the more densely populated islands throughout the Northwest (Grand Bahama and Abaco) and Central (Eleuthera, Exuma, Long Island and New Providence) Bahamas using different forensic marker systems. When autosomal STR markers are employed, the Bahamian collections were all found to receive differential contributions from the African, European, East Asian and Native American collections utilized in the analyses. Similar findings were also observed for two other Afro-Caribbean populations, Haiti and Jamaica, although the latter populace was found to share a greater proportion of its autosomal component with non-African sources than the former. On the contrary, analysis of the six Bahamian collections using high-resolution Y-chromosome markers identifies genetic signals emanating exclusively from Africans and Europeans, but this is likely the result of smaller sample sizes collected from each island and/or sex-biased gene flow from East Asian and Native American groups.
45

Geographic Patterns of Early Holocene New World Dental Morphological Variation

Stojanowski, Christopher, Johnson, Kent, Duncan, William N. 01 July 2013 (has links)
Dental anthropology played a seminal role in early studies of the peopling of the New World, and was a foundation of the early three wave model proposed by Greenberg, Turner and Zegura. In recent years, however, developments in anthropological genetics, craniometry, and archaeological discoveries have largely omit-ted dental anthropology from debates regarding Native American origins. Here we consider this situation and reassert dental anthropology's relevance to the topic by presenting an inter-individual analysis of Paleoindian and Paleoamerican dentitions. A small set of dental morphological variables was used to estimate Gower similarity coefficients between individual specimens. The resulting similarity matrix was ordinated using multidimensional scaling; all analyses were per-formed in Clustan v. 7.05. While results should be considered preliminary, patterns of variation suggest morphological similarity along both coasts of North and South America with a somewhat distinct grouping of North American Paleoindians deriving from more inland portions of the continent. This pattern is consistent with recent genetic scenarios, notably the bicoastal model presented by O'Rourke and Raff (2010), which indicates that Paleoindians may have taken multiple migration routes from Beringia, moving along both coasts as well as through the ice free corridor. Future studies may build on this work to reintegrate dental data and analysis into research concerning the peopling of the New World.
46

The portrayal of subjectivity in selected dystopian novels

Naudé, Bernard January 2015 (has links)
In his Truth and Method, Gadamer explains that subjectivity is the everyday understanding that allows us to engage with the world. Gadamer identifies three main aspects that effect our understanding, namely history, language and dialogue. Dystopian fiction is in a unique position to portray how systems of societal control affect and effect understanding, and thus subjectivity, because dystopian fiction primarily explores societies rather than only individuals. This dissertation applies Gadamer’s framework of subjectivity to George Orwell’s Nineteen Eighty-Four and Aldous Huxley’s Brave New World to analyse their portrayals of subjectivity critically. Huxley’s imagined world of test-tube births, rampant consumerism, feelies and orgy-porgies depicts a subjectivity that is nearly completely controlled through the manipulation of history, language and dialogue, with the exception of a few rebellious characters. But Orwell’s Oceania is far grimmer, and the systems of control in place to manipulate history, language and dialogue create a harsh environment in which Winston Smith, the protagonist, struggles to assert his individuality, his own subjectivity, until the liberating sexual relationship he has with Julia. Although both novels depict stringent measures of control, the possibility of rebellion is present in the worlds depicted in both novels, suggesting that despite the manipulation around subjectivity’s three main pillars, as identified by Gadamer, something else provides the impetus for the characters’ understanding of rebellion. Therefore, the study also analyses the characters’ pre-understandings, as explained by Nietzsche and Heidegger, as sources for a wider framework. Through the novels’ portrayals of rebellion, these pre-understandings are shown to complement and inform Gadamer’s framework of subjectivity. / Dissertation (MA)--University of Pretoria, 2015. / English / MA (English) / Unrestricted
47

Mosaic Landscape Use by a Primate Community of Northeastern Peru, with Particular Focus on Red Uakaris (Cacajao calvus ucayalii)

Hores, Rose M. 01 December 2018 (has links) (PDF)
Understanding spatial and temporal diversity and distribution patterns of species along with the drivers of these patterns has long been a theme of community ecology. Primates, a very species-rich taxonomic group, able to occupy various habitat types, are known for their broad behavioral repertoire and flexibility. This, in turn, allows them to adapt quickly to different ecological conditions. Therefore, they represent an ideal group for examining aspects of community ecology such as species diversity and co-occurrence, distribution patterns, and the ecological determinants of such factors. This dissertation investigates the ways in which members of a multispecies primate community inhabiting a mosaic landscape comprised of flooded and non-flooded forests in northeastern Peru (western Amazonia) distributes themselves across time and space. The main objectives of this study are threefold: 1) to categorize, confirm, and differentiate previously identified habitat types across a mosaic landscape; 2) to examine the diversity and distribution patterns (spatial and temporal) of a large multispecies primate community, and 3) to combine the habitat data with the primate data in order to determine which habitats are occupied by which species and to suggest ways in which the primates share and utilize the landscape throughout an annual cycle. However, special attention is paid to one particular species, the red uakari (Cacajao calvus ucayalii), because of its unusually large home and day ranges and its fluid social system known to change in size and composition daily and even hourly. One of the least studied primates to date, red uakaris, are investigated in order to determine whether or not their behavior varies across habitat types, seasons, and when other primates are present as they navigate a mosaic landscape. By identifying the ways in which uakaris modify their behaviors as they traverse multiple habitats throughout the year, determining both habitat-typical behaviors and seasonal behaviors exhibited by uakaris becomes possible. Moreover, shedding light on the community structure and habitat requirements of one of the least known primates has conservation implications. Research was conducted at the Tahuayo River Amazon Research Center (TRARC), located in northeastern Peru. Systematic data collection on primates and the environment occurred between September 2012 and February 2014, except April 2013. Sampling methods for primates consisted of two parts—a combination of line transect and reconnaissance (recce) surveys in order to determine encounter rates for each species across habitat types and 10-minute interval scan sampling during uakari follows in order to determine the effect that environmental and social factors have on their behavior as they traverse multiple habitats. Environmental sampling occurred in thirty plots established throughout the various habitat types. All trees within the test plots with a diameter breast height (DBH) > 10 cm were marked and the following parameters were recorded: DBH, height, and taxonomic classification. Additionally, plots were monitored monthly to record flooding data in order to determine variation in flooding patterns across habitat types. Plots allowed for the determination of which floristic variables and flood patterns are suitable to differentiate the habitat types described at the TRARC. Results indicate flood duration, average tree height, and (Importance Value Indices [IVIs] at the family, genus, and species levels) are suitable measures for defining and differentiating the five previously identified habitat types at the TRARC. Analysis of the entire primate community showed that the occurrence of species and patterns of distribution across a mosaic landscape vary throughout the year. Distribution patterns are more dependent on forest structure (habitat type) than on rainfall seasonality. While a few primates showed preferences for particular habitats (e.g., Lagothrix) or for certain seasons (e.g. Saimiri), the majority of primates demonstrated more generalized modes of ranging and foraging, with relatively equal encounter rates in all habitats across both wet and dry seasons. Results of the uakari data revealed that habitat and season had an effect on their behavior. There were meaningful differences in the behavioral categories of vocalizing, resting, moving, feeding, infant clinging, and being in polyspecific associations (PSAs) between flooded and non-flooded habitat types. Seasonal differences were seen for vocalizing, traveling, resting, and time spent in PSAs. Although results revealed that red uakaris spent the majority of the time alone (71.86%), when they were in PSAs with one other primate species, squirrel monkeys (Saimiri sciureus) were the most common monkeys. When uakaris were in PSAs with two other species, squirrel monkeys were always present, but woolly monkeys (Lagothrix lagotricha poeppigii) were the second most frequent species. In general, uakaris demonstrated behavioral differences across habitats and seasons. However, some behavioral consistencies across seasons were evident (e.g., moving, feeding, infant clinging), suggesting ecological flexibility in the species. Results of this dissertation provide a basis for understanding ecological parameters best suited for characterizing and differentiating habitat types in upper Amazonia and describe the diversity and distribution patterns of a multispecies community of primates occurring across a mosaic landscape, reinforcing the view that New World primates are largely ecological generalists within forest environments. Understanding the spatio-temporal relationships between species and their environments can aid in predictions of species occurrence/abundance and contribute to better management strategies and conservation prioritization.
48

Physical Mapping of Ribosomal Genes in New World Members of the Genus Chenopodium Using Fluorescence in Situ Hybridization

Sederberg, Maria C. 27 October 2008 (has links) (PDF)
The genus Chenopodium contains many economically important species in the New World, but is relatively understudied and poorly understood, especially in terms of evolutionary relationships. A better understanding of the structure of this genus could significantly help in breeding efforts on its cultivated members, notably the tetraploid C. quinoa and also certain varieties of C. berlandieri, also tetraploid. Of special concern is determining which diploid weed species are the most likely ancestors for C. quinoa, C. berlandieri, and the other tetraploid members of subsection Cellulata. The phylogeny can be understood in part by examining the ribosomal RNA loci and observing how many copies of the 5S and 45S loci each New World species contains. In this work, the 5S and 45S ribosomal RNA loci are characterized by means of fluorescence in situ hybridization in 23 Chenopodium species collected in the New World, with the 5S locus labeled red and the 45S locus labeled green. Based on these results, the pool of most likely candidate ancestor species for C. quinoa and C. berlandieri includes C. fremontii, C. incanum, C. neomexicanum, and C. watsonii.
49

The Tree of Life Symbol; Its Significance in Ancient American Religion

Briggs (Woodford), Irene M. 01 June 1950 (has links) (PDF)
Not too much is known today about religion of ancient Mesoamerica, and it will only be through an intensive comparative study of the various deities as presented in the heiroglyphic manuscripts and native writings, and of the symbolic religious art in the architectural and sculptural remains, that greater knowledge of the subject will be gained. The "Tree of Life," one of the most striking religious symbols of the area, may be one key to such knowledge.
50

Practicas Escriturales Femeninas: Espacialidad e Identidad en Epistolas en la Colonia (Rio de la Plata, Siglos XVI-XVII)

Silva, Yamile 13 May 2011 (has links)
The importance of the letter as a means for social, personal and intellectual expression for humanists has been highlighted in various studies. For those studies, its value resides in its effectiveness in responding more directly to the presence of a new pool of readers giving rise to a new cultural type, transforming it into the emblematic genre of the humanists. I am interested in considering the influence of epistolary models in the New World, because, as these models were transferred to a new context, they acquired new forms that responded to the needs of communication, representation, symbolization and, finally, a new rhetoric. For the purposes of this dissertation, I will depart from the conception of the letter in the New World as a “polysynthetic” genre; that is to say, inasmuch as I wish to respond to the plurality of communicative needs that arose from the new contexts that were unforeseen by the humanist rhetoric, I will consider the letters from the New World as emerging from and forming part of other genres: accounts, petitions, diaries, among others. The starting point for this dissertation is the thorough reading and analysis of eleven unpublished letters, all written by women, currently located at the Archivo General de Indias in Seville and sent from the Rio de la Plata during the XVI and XVII centuries. In my investigation, I intend to demonstrate how the authors used the writing of such documents as an empowering practice. Secondly, I will prove that these first epistles, written from America, do not necessarily belong to the ars epistolandi, but to the ars dictaminis. Furthermore, this change in disctinction requires a critical review of the current state of classical letters. Finally, I maintain that these letters provide a space for the emergence of the authors‟ identity. In other words, I understand and ground the conclusions of this work on the fact that space culturally shapes gender, but that gender acts in the production of such spaces as well. The participation of female authors by means of these letters merges them with that spatiality in a process both of production and reproduction, since, as a conscience building act, the “I” is turned into text in order to discuss on/about the space.

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