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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.
141

Unveiling her majesty's purposes Malory's Guinevere as structural center /

Mikahoff, Justine C. January 2008 (has links) (PDF)
Thesis (M.A.)--University of North Carolina Wilmington, 2008. / Title from PDF title page (viewed September 22, 2008) Includes bibliographical references (p. 87-89)
142

Low level hepatitis B virus carriers : its detection by polymerase chain reaction based assays and its clinical significance /

Chung, Hau-tim. January 1995 (has links)
Thesis (M.D.)--University of Hong Kong, 1996. / Includes bibliographical references (leaf 102-116).
143

A case study : the Queen Sirikit National Convention Center /

Pongcharoenkiat, Nongluk. January 1992 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 1992. / Typescript. Includes bibliographical references (81-82).
144

Low level hepatitis B virus carriers its detection by polymerase chain reaction based assays and its clinical significance /

Chung, Hau-tim. January 1995 (has links)
Thesis (M.D.)--University of Hong Kong, 1996. / Includes bibliographical references (leaf 102-116). Also available in print.
145

Redevelopment of Macpherson Playground and Queen Elizabeth II Youth Centre

Chan, Pan-hang, Marco. January 1997 (has links)
Thesis (M.Arch.)--University of Hong Kong, 1997. / Includes special report study entitled : Public routes and spatial design. Includes bibliographical references. Also available in print.
146

Configured Visibility in 'Elizabeth I as Europa': The Queen's Represented Body in Context of the Geographical Imagination

Parsons, Heather Marie January 2006 (has links) (PDF)
No description available.
147

The Regulation of Worker Reproduction in the Ant Aphaenogaster cockerelli

January 2011 (has links)
abstract: The repression of reproductive competition and the enforcement of altruism are key components to the success of animal societies. Eusocial insects are defined by having a reproductive division of labor, in which reproduction is relegated to one or few individuals while the rest of the group members maintain the colony and help raise offspring. However, workers have retained the ability to reproduce in most insect societies. In the social Hymenoptera, due to haplodiploidy, workers can lay unfertilized male destined eggs without mating. Potential conflict between workers and queens can arise over male production, and policing behaviors performed by nestmate workers and queens are a means of repressing worker reproduction. This work describes the means and results of the regulation of worker reproduction in the ant species Aphaenogaster cockerelli. Through manipulative laboratory studies on mature colonies, the lack of egg policing and the presence of physical policing by both workers and queens of this species are described. Through chemical analysis and artificial chemical treatments, the role of cuticular hydrocarbons as indicators of fertility status and the informational basis of policing in this species is demonstrated. An additional queen-specific chemical signal in the Dufour's gland is discovered to be used to direct nestmate aggression towards reproductive competitors. Finally, the level of actual worker-derived males in field colonies is measured. Together, these studies demonstrate the effectiveness of policing behaviors on the suppression of worker reproduction in a social insect species, and provide an example of how punishment and the threat of punishment is a powerful force in maintaining cooperative societies. / Dissertation/Thesis / Ph.D. Biology 2011
148

První recepční vlna Rukopisu Královédvorského a Rukopisu Zelenohorského v letech 1817-1852. / The first Wawe of Reception of Rukopis Královédvorský and Rukopis Zelenohorský in the peroid 1817-1852.

KONČELÍKOVÁ, Iveta January 2011 (has links)
The graduation thesis The first Wave of Reception of Rukopis Královédvorský and Rukopis Zelenohorský in the period 1817 - 1852 documents the first wave of reception of Rukopis Královédvorský and Rukopis Zelenohorský. Mostly we drew from materials from periodical references and also from contemporary literature. In the first part of this thesis we introduce RKZ closer, we bring chronological survey of RKZ?s publications and we interpret them. In separate chapter we present reaction to Germen professors J. H. Dambeck and J. G. Meinert to discovery RKZ. Also we acquaint with foreign language translations of RKZ. The conclusion summarizes we represent work of art, that are affected by the existence of manuscripts RKZ.
149

Biologia, organização social e ecologia comportamental de Mischocyttarus nomurae Richards, 1978 (Hymenoptera, Vespidae) / Biology, social organization and behavioral ecology of Mischocyttarus nomurae Richards, 1978 (Hymenoptera, Vespidae)

Rocha, Agda Alves da [UNESP] 13 March 2017 (has links)
Submitted by AGDA ALVES DA ROCHA null (rocha.agda@gmail.com) on 2017-11-28T19:58:09Z No. of bitstreams: 1 Rocha_Agda_2017.pdf: 3754795 bytes, checksum: 147e7d00c8330084beb9e117e77ac336 (MD5) / Approved for entry into archive by LUCIA SILVA PARRA null (lucia@ia.unesp.br) on 2017-11-29T16:34:46Z (GMT) No. of bitstreams: 1 rocha_aa_dr_rcla.pdf: 3754795 bytes, checksum: 147e7d00c8330084beb9e117e77ac336 (MD5) / Made available in DSpace on 2017-11-29T16:34:46Z (GMT). No. of bitstreams: 1 rocha_aa_dr_rcla.pdf: 3754795 bytes, checksum: 147e7d00c8330084beb9e117e77ac336 (MD5) Previous issue date: 2017-03-13 / A vespa social basal Mischocyttarus nomurae Richards tem ocorrência exclusiva no Brasil e foi registrada nos estados do Ceará, Bahia e Minas Gerais. Na Bahia, ocorre em três municípios da Chapada Diamantina: Lençóis, Mucugê e Rio de Contas. Nesta última, foram estudadas populações com relação à sua biologia básica, buscando responder perguntas relacionadas aos seguintes aspectos: morfologia externa dos imaturos, perfis comportamental, morfofisiológico e químico, substituição de rainhas, arquitetura de ninhos e hábitos de nidificação. Com relação à morfologia dos imaturos, a taxa média de crescimento da larva foi de 1,48. Com exceção da larva de 1o ínstar, que revelou-se menor do que o ovo, a espécie apresentou o padrão do grupo: presença de lobos, estes em número de dois e projetados para a frente, só totalmente desenvolvidos quando a larva atinge o 5o instar; as mandíbulas das larvas de 5o instar apresentam um único dente alongado e o primeiro espiráculo é mais do que duas (3,1) vezes maior em diâmetro que os demais. As cápsulas cefálicas da larva de 5º ínstar e da pré-pupa não diferiram significativamente. Após os estudos dos perfis morfofisiológico, químico e comportamental, foi verificado que as fêmeas de M. nomurae não apresentam distinção em sua morfologia externa, mas cinco tipos de desenvolvimento ovariano foram observados, três menos desenvolvidos (A1, A2 e B) e dois mais desenvolvidos (C e D). Foram detectados 34 compostos na sua cutícula, cujas cadeias variaram de 18 a 33 átomos de carbono. Os compostos consistiram em alcanos lineares (9%), alcanos ramificados (89%) e alcenos (2%). Foram identificados três grupos de fêmeas: Operária 1, Operária 2 e Rainha e a análise discriminante do perfil dos hidrocarbonetos cuticulares relacionada a esses grupos de fêmeas apresentou um p-valor significativo (Wilks' lambda= 0,135, F= 1.665, p = 0,0227). Após oito dias da remoção da fêmea dominante do ninho, em todas as colônias, exceto uma, a fêmea era anteriormente a fêmea β. Fêmeas com ovários não desenvolvidos podem realizar comportamentos de fêmea dominante, assim como uma fêmea com ovário desenvolvido comportouse como forrageadora típica. Houve diferença entre algumas atividades exercidas pelas fêmeas posicionadas em 2º lugar no ranking (fêmea β) e as demais fêmeas do ninho (3ª posição em diante), antes e após a remoção experimental da rainha. M. nomurae apresenta um sistema de gerontocracia flexível na sua substituição de rainhas e suas fêmeas sucessoras tornam-se mais agressivas que as rainhas originais, assumindo tarefas de dominantes, mesmo sem estarem inseminadas. Como algumas espécies do gênero, a maioria das colônias apresentou hábitos de nidificação relacionados a ambientes antrópicos. Destes, 61,2% das colônias utilizaram material de origem vegetal (madeira e palha). A altura média de construção do ninho com relação ao solo foi elevada, semelhante as das demais espécies do gênero (2,20 ± 0,83, 0,45 – 5,00m). A maioria dos ninhos foi construída com o favo voltado para baixo (70,15%) e em substrato horizontal (53,73%). O único favo do ninho pode ser arredondado ou elíptico, raramente retangular. O número de camadas de mecônio variou de zero a cinco e a espécie M. nomurae apresenta ninhos pequenos, com suas colônias apresentando um baixo número de adultos produzidos, embora haja uma alta taxa de reutilização de células. / The basal social wasp Mischocyttarus nomurae Richards occurs exclusively in Brazil, having been recorded there in the states of Ceará, Bahia, and Minas Gerais. It is known to occur in three municipalities in the Chapada Diamantina mountains of Bahia State: Lençóis, Mucugê, and Rio de Contas. Population studies were undertaken in the latter municipality to address questions related to the basic biology of M. nomurae: the external morphologies of the immatures; their behavior; their morpho-physiological and chemical profiles; queen substitutions; nest architecture, and nidification habits. In terms of the morphologies of the immatures, the mean larval growth rate was 1.48. With the exception of the 1st instar larvae, which are smaller than the eggs, the species demonstrated the standard developmental pattern for the group: the presence of lobes (two) projected forward, those only becoming fully developed in the 5th instar stage; mandibles in the 5th instar stage with a single elongated tooth, and the first spiracle with a diameter more than two (3.1) times greater than the others. The cephalic capsules of the 5th instar larvae and pre-pupae do not significantly differ. Studies of the morpho-physiological, chemical, and behavioral profiles of those wasps indicated that the females of M. nomurae do not have distinct external morphologies, although five different types of ovarian development were observed: three less-developed types (A1, A2 and B); and two more developed types (C and D). Thirty-four distinct chemical compounds were detected in the cuticle, with carbon chains varying from 18 to 33 atoms. Those carbon compounds consisted of linear alkanes (9%), branched alkanes (89%), and alkenes (2%). Three groups of females were identified: Workers 1, Workers 2, and Queens. Discriminant analyses of the cuticular hydrocarbons of those female groups demonstrated a significant p-value (Wilks' lambda= 0.135, F= 1.665, p = 0.0227). Eight days after the removal of the dominant female from the nest, female substitutions were observed all of the colonies (except one) assuming the condition of a new queen (from the ranks of the β females). Females with undeveloped ovaries do not perform behaviors associated with dominant females, nor do females with developed ovaries behave as typical foragers. There were differences between some of the activities performed by second-rank females (β females) and other females in the same nest (from the 3rd position down), both before and after experimentally removing the queen. M. nomurae demonstrates a flexible gerontocratic system in terms of queen substitutions, and the new queens become more aggressive than the original queens, assuming dominant roles even without being inseminated. As with many species of the same genus, most of the colonies nidify in anthropically modified environments. Of those colonies, 61.2% built nests using plant material (wood and leaves). The nests were constructed at reasonably high mean heights above ground level (2.20 ± 0.83 m; from 0.45 – 5.00 m), similar to other species of the genus. Most of the nests were affixed to horizontal substrates (53.73%) and constructed with the comb facing downward (70.15%). A nest comb can be rounded or elliptic, rarely rectangular. The numbers of meconium layers varied from zero to five. The nests of M. nomurae are generally small, with their colonies producing only small numbers of adults - although with high rates of comb cell reutilization.
150

Evolução dos sistemas de acasalamento em abelhas sem ferrão (Apidae, Meliponini) / Evolution of mating systems in stingless bees (Apidae, Meliponini)

Ayrton Vollet Neto 25 August 2016 (has links)
O sistema de acasalamentos das abelhas sociais é intrigante. As rainhas acasalam durante uma curta janela de tempo nas fases inicias de suas vidas, armazenando o esperma pelo resto de suas vidas. Enquanto as rainhas das abelhas sem ferrão (Meliponini) e de mamangavas (Bombini) se acasalam com um ou poucos machos (monândricas), as rainhas de espécies representantes do gênero Apis (Apini) acasalam-se com vários machos (poliândricas). Diversas hipóteses têm sido propostas para compreender os benefícios do comportamento extremamente promíscuo das rainhas do gênero Apis. Porém, pouco foi feito para entender as igualmente intrigantes pressões seletivas que mantém a monandria em um grupo tão diverso quanto o das abelhas sem ferrão. No presente estudo, investigamos como as forças seletivas causadas pelas produção de machos diploides (uma consequência natural do sistema de determinação sexual em Hymenoptera) podem afetar o sistema de acasalamento da abelha sem ferrão brasileira, Scaptotrigona depilis. Em particular, rainhas que realizam um acasalamento pareado para o locus sexual (i.e., acasalam com um macho que possui o mesmo alelo sexual) terão o seu fitness reduzido porque elas serão executadas em colônias com 50% de machos diploides entre sua cria diploide. Acasalar-se com mais de um macho aumentam as chances de um acasalamento pareado, mas reduz a proporção de machos diploides na cria. Por meio da manipulação dos favos de cria de colônias experimentais, nós testamos se a mortalidade de rainhas com proporções menores de machos diploides na cria terão taxas de mortalidade similares à de rainhas em colônias com 0% ou 50% de machos diploides na cria. Para isso, obtivemos rainhas produzindo machos diploides nesta espécie e estudamos alguns detalhes de sua biologia, em particular, a viabilidade e morfologia de seus espermatozoides e comportamento fora de suas colônias (Capítulo 1). Nós verificamos se a rainha morre na presença de machos diploides, como este comportamento é predominante na população, e quais os possíveis mecanismos que desencadeiam este comportamento (Capítulo 2). Finalmente, verificamos se a mortalidade de rainhas em colônias com proporções menores de machos diploides na cria (simulando acasalamentos múltiplos) é mais próxima da mortalidade de rainhas em colônias com 0 ou 50% de machos diploides (Capítulo 3). Verificamos que os machos diploides de S. depilis são viáveis e juntam-se a agregados reprodutivos. Seus espermatozoides possuem a mesma viabilidade que os dos machos haploides, porém possuem a cabeça e a cauda maiores. As rainhas são mortas na presença de cerca de 50% de machos diploides na cria e esse comportamento é muito difundido na população estudada, com 100% de morte das rainhas (n=20). O perfil químico de hidrocarbonetos cuticulares dos machos diploides é quantitativamente diferente dos machos haploides, sugerindo que pode conter informações para que a rainha seja executada. No entanto, por meio da contagem de espermatozoides na espermateca de rainhas recém acasaladas e com um ano de idade foi possível observar que o esgotamento de espermatozoides pode afetar a expectativa de vida das rainhas. Isso sugere que o sinal para execução da rainha também pode estar associado a uma quantidade grande de machos emergindo, como um sinal de esgotamento de espermatozoides da rainha, ao invés da ploidia dos machos. Rainhas em colônias com cerca de 25% de machos diploides emergindo foram mortas em proporções semelhantes à de rainhas em colônias com 50% de machos diploides. Isso indica que esse comportamento causa uma pressão seletiva contra os acasalamentos duplos nessa espécie, pois ao acasalar duas vezes a rainha dobra as chances de realizar um acasalamento pareado e a mortalidade é igual à de rainhas que se acasalam uma única vez. / The mating systems of social bees is intriguing. Queens mate within a narrow time window very early in their lives, storing male sperm for their entire lifespan. In bumblebees (Bombini) and stingless bees (Meliponini), queens usually mate with a single male (monandry), while the queens of Apis species (Apini) mate with several males (polyandry). Several hypothesis have been proposed to understand the benefits of the extreme polyandry of honey bees. However, very little have been done in order to understand the equally intriguing selective forces that make such a diverse group as stingless bees as monandrous. In the present study we investigate how the selective force imposed by the chances of producing diploid males (a natural consequence of sex determination system of Hymenoptera) can affect the mating system of the Brazilian stingless bee Scaptotrigona depilis. In particular, queens that make a matched mating for the sex locus (i.e., mating with a male with the same sex allele) will have reduced fitness because queens are executed when producing 50% of diploid males amongst her diploid offspring. Mating with more males increase the chances of a matched mating, but reduces the proportion of diploid males on their brood. By manipulating the brood combs of experimental colonies, we tested whether queens with smaller proportions of diploid males (25%) will have mortality rates similar to queens in colonies with 0% or 50% diploid males. For that, we obtained queens producing diploid males and studied details of diploid males biology, in particular their sperm viability and morphology, and their behaviour out of their mother colonies (Chapter 1). We verified how prevalent queen execution behaviour under diploid male production is on this species, and the possible proximate mechanisms that trigger this behaviour (Chapter 2). Finally, we verified whether queen mortality in colonies with lower proportion of diploid males (simulating multiple mating) is closer to colonies with 50% or 0% of diploid males (Chapter 3). We verified that diploid males of S. depilis are viable and can join reproductive aggregations. Their sperm cells have the same viability of haploid males, but have longer sperm head and tail cells. Queens are executed in the presence of 50% of diploid males, and this behaviour is very prevalent on the studied population, with 100% of queen death (n=20). The cuticular hydrocarbon chemical profile of diploid males is quantitatively different from haploid males, suggesting that workers could use it as a signal for queen execution. However, sperm count of newly mated queens and one-year-old queens showed that sperm depletion might affect queen lifespan. This suggests that the signal for queen execution could also be related to a high number of males emergence, as a signal of queen sperm depletion, instead of male ploidy. Queens mortality in colonies with 25% of diploid males was similar to queens in colonies with 50%. This indicates that double mating is selected against regarding this selective pressure, since mating twice will increase the chances of a matched mating and queen mortality will be the same as single mated queens.

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