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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

Identity and identification affirmative action in India and the United States /

Dudley-Jenkins, Laura. January 1900 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1998. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
102

Ontogenia da casta de soldados no cupim praga Heterotermoes tenuis (Isoptera, Rhinotermitidae) /

Laranjo, Lara Teixeira. January 2011 (has links)
Orientador: Ana Maria Costa Leonardo / Banca: Fabiana Elaine Casarin dos Santos / Banca: Alexandre Vasconcellos / Resumo: Heterotermes tenuis é uma espécie de cupim nativa da região Neotropical, conhecida como praga agrícola e urbana. Essa espécie causa sérios danos econômicos em culturas de cana-de-açúcar e ataca madeiras e derivados celulósicos em cidades. H. tenuis apresenta hábitos subterrâneos e indivíduos de pequeno porte, com soldados dimórficos. A diferenciação de castas nos cupins é um processo complexo ainda não totalmente esclarecido. Em vista disso, o objetivo do presente estudo foi entender a diferenciação de soldados no cupim H. tenuis a partir de agrupamentos de operários. Para isso, no Capítulo I, foram apresentados os resultados dos bioensaios desenvolvidos para observar a influência de fatores extrínsecos e intrínsecos, entre eles, número de operários agrupados, temperatura, fontes alimentares e ingestão de diferentes concentrações de piriproxifen, um análogo de hormônio juvenil. Agrupamentos com 50, 100, 200 e 300 operários formaram uma baixa proporção de soldados. O uso de piriproxifen originou pré-soldados e também intercastas, sendo que a formação de pré-soldados foi maior na concentração de 10 ppm. Já no Capítulo II, o foco do estudo foram as mudanças morfológicas externas e internas ocorridas durante o processo de diferenciação de soldados. Para isso, operários, pré-soldados, soldados e intercastas foram submetidos à análise biométrica e histológica. Além disso, foi realizada a identificação do sexo dos soldados e a determinação da duração do ínstar de pré-soldado. Este ínstar durou cerca de 15 dias em temperatura ambiente e os pré-soldados diferiram biometricamente dos soldados, principalmente, pelo comprimento da cápsula cefálica e do tórax. As intercastas obtidas foram do tipo operário-soldado. Soldados menores de H. tenuis foram todos machos enquanto os soldados maiores apresentaram uma proporção de aproximadamente... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Heterotermes tenuis is a native species of termite, known as an agricultural and urban pest. This species causes serious economic damages on crops of sugar cane and attacks wood and cellulosic derivatives in cities. H. tenuis has subterranean habits and small individuals, with dimorphic soldiers. Differentiation of castes in termites is a complex process not yet fully understood. In this study we aimed to understand the differentiation of H. tenuis soldiers, originated from groups of workers. In Chapter I, we presented the results of bioassays developed to observe the influence of extrinsic and intrinsic factors, including, number of grouped workers, temperature, food sources and ingestion by the workers of different concentrations of pyriproxyfen, a juvenile hormone analog. Groups of 50, 100, 200 and 300 workers originated a low proportion of soldiers. The use of pyriproxyfen induced presoldiers and also intercastes. Presoldiers were produced in a large number in a concentration of 10 ppm. In Chapter II, the focus of the study was the external and internal morphological changes occurred during the process of differentiation of soldiers. For that, workers, presoldiers, soldiers and intercastas were histologically and morphometrically analyzed. In addition, we performed the sex identification of the soldiers and determined the duration of the presoldier instar. This instar lasted about 15 days at a variable temperature and the presoldiers biometrically differed from soldiers mainly by the length of head capsule and thorax. The intercastes obtained were from the worker-soldier type. Minor soldiers of H. tenuis were all males while the major soldiers had a ratio of approximately 1:1 between males and females. The exocrine glands of the individuals studied were compared and the histology showed that workers had greater development of the salivary, mandibular and sternal glands... (Complete abstract click electronic access below) / Mestre
103

Market power : traders, farmers, and the politics of accumulation in Pakistani Punjab

Amirali, Asha January 2017 (has links)
This thesis examines traders' strategies of accumulation in agricultural commodity markets in Pakistani Punjab. It contributes to the literature on markets as social and political institutions as well as to broader debates on patronage, informality, urbanization, and class formation in South Asia. The principal aim of the thesis is to identify the institutions and ideologies facilitating exchange and study how they function in the market. It also aims to account for the increased political importance of traders, understood as members of Pakistan's intermediate classes, and reflect on the nature of their political participation. Non-programmatic, functional alignments are shown to be the norm and compatible with both military and democratic regimes. Through a close look at activities in one agricultural commodity market - or mandi, as it is known in Punjab - the present work explores the practices and linkages traders cultivate to bolster their economic and political power. Plunging into everyday mandi life in small-town Punjab, it illustrates how customary institutions articulate with the state and capital to co-regulate economic activity and create conditions for durable domination. Enmeshment in patron-client relations, links with the local state, associational activity, ownership and control of capital, and thick social ties are demonstrated to be key means by which wealth and power are accumulated. Class is shown to articulate closely with caste and kinship while being irreducible to them, and the role of dominant social institutions is demonstrated to be highly variable across the many processes ongoing in the market.
104

Contentious spaces : caste, commemorations and production of political community in South India

Damodaran, Karthikeyan January 2018 (has links)
In their struggle for equality in Tamil Nadu, Dalits (ex-untouchables) often challenge prevailing caste norms by appropriating practices and conventions of locally dominant groups. This study examines how the Dalit Pallars of Tamil Nadu engage in various forms of socio-cultural and political assertions to challenge their marginality. It looks at the performative aspects of such struggles by focusing on Guru Pujas; public performances undertaken to pay homage to late social and political icons/leaders. As annual events these pujas have enabled Thevars, the local dominant caste, to showcase their community’s strength and power through the appropriation of public space. However, the same mode of public performance, which was integral to the public production and consolidation of the dominant caste as a political community, has been replicated by historically marginalised castes. This is reflected tangibly through visual aesthetics during commemorations. Following the Thevars and Nadars, a section of the Pallars are engaged in proclaiming the historical past by asserting that they too form the royal lineage and are competing with Thevar iconography to challenge the cultural dominance of Thevars. As quotidian forms of oppression and violence mark the spatial relationship between these castes, these performances provide a micro-lens to understand the dynamics of how local power is generated and made visible through a politics inscribed in space. Recent decades have witnessed increased competition over public symbols and the strategic location of caste-specific cultural signifiers – including competition over style and performance – and a heightened contest over the occupation of public space. Thus, the study maps the Pallar assertion and the challenges posed by Thevar retaliation.
105

Essays in Growth and Development

January 2015 (has links)
abstract: The dissertation consists of three essays that deal with variations in economic growth and development across space and time. The essays in particular explore the importance of differences in occupational structures in various settings. The first chapter documents that intergenerational occupational persistence is significantly higher in poor countries even after controlling for cross-country differences in occupational structures. Based on this empirical fact, I posit that high occupational persistence in poor countries is symptomatic of underlying talent misallocation. Constraints on education financing force sons to choose fathers' occupations over the occupations of their comparative advantage. A version of Roy (1951) model of occupational choice is developed to quantify the impact of occupational misallocation on aggregate productivity. I find that output per worker reduces to a third of the benchmark US economy for the country with the highest level of occupational persistence. In the second chapter, I use occupational prestige as a proxy of social status to estimate intergenerational occupational mobility for 50 countries spanning the breadth of world's income distribution for both sons and daughters. I find that although relative mobility varies significantly across countries, the correlation between relative mobility and GDP per capita is only mildly positive for sons and is close to zero for daughters. I also consider two measures of absolute mobility: the propensity to move across quartiles and the propensity to move relative to father's occupational prestige. Similar to relative mobility, the first measure of absolute mobility is uncorrelated with GDP per capita. The second measure, however, is positively correlated with GDP per capita with correlations being significantly higher for sons compared to daughters. The third chapter analyses to what extent the growth in productivity witnessed by India during 1983--2004 can be explained by a better allocation of workers across occupations. I first document that the propensity to work in high-skilled occupations relative to high-caste men increased manifold for high-caste women, low-caste men and low-caste women during this period. Given that innate talent in these occupations is likely to be independent across groups, the chapter argues that the occupational distribution in the 1980s represented talent misallocation in which workers from many groups faced significant barriers to practice an occupation of their comparative advantage. I find that these barriers can explain 15--21\% of the observed growth in output per worker during the period from 1983--2004. / Dissertation/Thesis / Doctoral Dissertation Economics 2015
106

Variação morfofisiológica das castas da vespa enxameante neotropical Polybia (Trichothorax) ignobilis durante sua ontogenia colonial (Hymenoptera, Vespidae, Epiponini) /

Desuó, Ivan Cesar. January 2008 (has links)
Orientador: Sulene Noriko Shima / Banca: Sidnei Mateus / Banca: Fernando Barbosa Noll / Resumo: A família Vespidae é um grupo chave para o entendimento da origem do comportamento social nos Hymenoptera, pois inclui desde espécies solitárias que não apresentam qualquer grau de socialidade até espécies que são altamente sociais como os Epiponini (Hymenoptera:Vespidae). A separação em castas é uma das pedras fundamentais da evolução dos insetos sociais, pois a presença de uma grande diferenciação entre as castas indica um maior grau de socialidade. Neste contexto, as vespas neotropicais pertencentes à tribo Epiponini despertam grande interesse em estudos de evolução de castas, pois além de apresentarem colônias poligínicas pode se observar um grande espectro de variação ocorrendo desde espécies com castas morfologicamente incipientes até distintas. Além disso, para uma dada espécie, o perfil de diferenciação morfológica entre as castas pode variar ao longo do ciclo colonial, evidenciando uma grande flexibilidade adaptativa frente às diferentes situações enfrentadas pela colônia ao longo de seu desenvolvimento. Diferenças morfofisiológicas entre as castas de 6 colônias em diferentes fases do desenvolvimento colonial de Polybia (Trychothorax) ignobilis foram analisadas. Para determinar as diferenças morfológicas entre as castas, foram medidas 13 varíaveis corporais externas provenientes da cabeça, mesossoma, metassoma e asa. Os ovários foram fotografados e esquematizados, a inseminação, idade relativa, a quantidade de tecido gorduroso e a condição morfológica da glândula de Richards foram analisadas. As fêmeas apresentaram uma seqüência gradual no padrão de desenvolvimento ovariano, desde ovaríolos... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The Vespidae family is a key group in evolutionary studies of sociality in Hymenoptera due to the occurrence of every step of social organization including species whose do not present any degree of sociality until those which are highly social, such as the Epiponini (Hymenopter: Vespidae). The separation into castes is one of the most important features of social insects and the presence of a higher level of caste differentiation indicates a well defined reproductive division of labor and consequently a higher degree of sociality. Morphological studies of caste differentiation in Neotropical social wasps concentrate mainly in the Epiponini tribe, once it's ecologically abundant in Neotropics and presents a wide spectrum of variability of caste systems ranging from species with a slightly caste differentiation to those with conspicuous body differences. Besides, patterns of caste differentiation may vary according the colony cycle mainly in response to environmental changes which may affect the colony dynamics. Morphological and physiological differences between castes of 6 colonies of Polybia (Trychothorax) ignobilis were analyzed. Measurements were taken from 13 morphometric variables regarding the head, metasoma, mesosoma and wing... (Complete abstract click electronic access below) / Mestre
107

Ontogenia da casta de soldados no cupim praga Heterotermoes tenuis (Isoptera, Rhinotermitidae)

Laranjo, Lara Teixeira [UNESP] 03 June 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:14Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-06-03Bitstream added on 2014-06-13T20:40:01Z : No. of bitstreams: 1 laranjo_lt_me_rcla.pdf: 1444025 bytes, checksum: 5b1c2c601622479b8f8fb4e3845e2c28 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Heterotermes tenuis é uma espécie de cupim nativa da região Neotropical, conhecida como praga agrícola e urbana. Essa espécie causa sérios danos econômicos em culturas de cana-de-açúcar e ataca madeiras e derivados celulósicos em cidades. H. tenuis apresenta hábitos subterrâneos e indivíduos de pequeno porte, com soldados dimórficos. A diferenciação de castas nos cupins é um processo complexo ainda não totalmente esclarecido. Em vista disso, o objetivo do presente estudo foi entender a diferenciação de soldados no cupim H. tenuis a partir de agrupamentos de operários. Para isso, no Capítulo I, foram apresentados os resultados dos bioensaios desenvolvidos para observar a influência de fatores extrínsecos e intrínsecos, entre eles, número de operários agrupados, temperatura, fontes alimentares e ingestão de diferentes concentrações de piriproxifen, um análogo de hormônio juvenil. Agrupamentos com 50, 100, 200 e 300 operários formaram uma baixa proporção de soldados. O uso de piriproxifen originou pré-soldados e também intercastas, sendo que a formação de pré-soldados foi maior na concentração de 10 ppm. Já no Capítulo II, o foco do estudo foram as mudanças morfológicas externas e internas ocorridas durante o processo de diferenciação de soldados. Para isso, operários, pré-soldados, soldados e intercastas foram submetidos à análise biométrica e histológica. Além disso, foi realizada a identificação do sexo dos soldados e a determinação da duração do ínstar de pré-soldado. Este ínstar durou cerca de 15 dias em temperatura ambiente e os pré-soldados diferiram biometricamente dos soldados, principalmente, pelo comprimento da cápsula cefálica e do tórax. As intercastas obtidas foram do tipo operário-soldado. Soldados menores de H. tenuis foram todos machos enquanto os soldados maiores apresentaram uma proporção de aproximadamente... / Heterotermes tenuis is a native species of termite, known as an agricultural and urban pest. This species causes serious economic damages on crops of sugar cane and attacks wood and cellulosic derivatives in cities. H. tenuis has subterranean habits and small individuals, with dimorphic soldiers. Differentiation of castes in termites is a complex process not yet fully understood. In this study we aimed to understand the differentiation of H. tenuis soldiers, originated from groups of workers. In Chapter I, we presented the results of bioassays developed to observe the influence of extrinsic and intrinsic factors, including, number of grouped workers, temperature, food sources and ingestion by the workers of different concentrations of pyriproxyfen, a juvenile hormone analog. Groups of 50, 100, 200 and 300 workers originated a low proportion of soldiers. The use of pyriproxyfen induced presoldiers and also intercastes. Presoldiers were produced in a large number in a concentration of 10 ppm. In Chapter II, the focus of the study was the external and internal morphological changes occurred during the process of differentiation of soldiers. For that, workers, presoldiers, soldiers and intercastas were histologically and morphometrically analyzed. In addition, we performed the sex identification of the soldiers and determined the duration of the presoldier instar. This instar lasted about 15 days at a variable temperature and the presoldiers biometrically differed from soldiers mainly by the length of head capsule and thorax. The intercastes obtained were from the worker-soldier type. Minor soldiers of H. tenuis were all males while the major soldiers had a ratio of approximately 1:1 between males and females. The exocrine glands of the individuals studied were compared and the histology showed that workers had greater development of the salivary, mandibular and sternal glands... (Complete abstract click electronic access below)
108

Variação morfofisiológica das castas da vespa enxameante neotropical Polybia (Trichothorax) ignobilis durante sua ontogenia colonial (Hymenoptera, Vespidae, Epiponini)

Desuó, Ivan Cesar [UNESP] 17 December 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-12-17Bitstream added on 2014-06-13T20:40:04Z : No. of bitstreams: 1 desuo_ic_me_rcla.pdf: 959937 bytes, checksum: d107c29f203623584bfa1329d44dc149 (MD5) / Universidade Estadual Paulista (UNESP) / A família Vespidae é um grupo chave para o entendimento da origem do comportamento social nos Hymenoptera, pois inclui desde espécies solitárias que não apresentam qualquer grau de socialidade até espécies que são altamente sociais como os Epiponini (Hymenoptera:Vespidae). A separação em castas é uma das pedras fundamentais da evolução dos insetos sociais, pois a presença de uma grande diferenciação entre as castas indica um maior grau de socialidade. Neste contexto, as vespas neotropicais pertencentes à tribo Epiponini despertam grande interesse em estudos de evolução de castas, pois além de apresentarem colônias poligínicas pode se observar um grande espectro de variação ocorrendo desde espécies com castas morfologicamente incipientes até distintas. Além disso, para uma dada espécie, o perfil de diferenciação morfológica entre as castas pode variar ao longo do ciclo colonial, evidenciando uma grande flexibilidade adaptativa frente às diferentes situações enfrentadas pela colônia ao longo de seu desenvolvimento. Diferenças morfofisiológicas entre as castas de 6 colônias em diferentes fases do desenvolvimento colonial de Polybia (Trychothorax) ignobilis foram analisadas. Para determinar as diferenças morfológicas entre as castas, foram medidas 13 varíaveis corporais externas provenientes da cabeça, mesossoma, metassoma e asa. Os ovários foram fotografados e esquematizados, a inseminação, idade relativa, a quantidade de tecido gorduroso e a condição morfológica da glândula de Richards foram analisadas. As fêmeas apresentaram uma seqüência gradual no padrão de desenvolvimento ovariano, desde ovaríolos... / The Vespidae family is a key group in evolutionary studies of sociality in Hymenoptera due to the occurrence of every step of social organization including species whose do not present any degree of sociality until those which are highly social, such as the Epiponini (Hymenopter: Vespidae). The separation into castes is one of the most important features of social insects and the presence of a higher level of caste differentiation indicates a well defined reproductive division of labor and consequently a higher degree of sociality. Morphological studies of caste differentiation in Neotropical social wasps concentrate mainly in the Epiponini tribe, once it’s ecologically abundant in Neotropics and presents a wide spectrum of variability of caste systems ranging from species with a slightly caste differentiation to those with conspicuous body differences. Besides, patterns of caste differentiation may vary according the colony cycle mainly in response to environmental changes which may affect the colony dynamics. Morphological and physiological differences between castes of 6 colonies of Polybia (Trychothorax) ignobilis were analyzed. Measurements were taken from 13 morphometric variables regarding the head, metasoma, mesosoma and wing... (Complete abstract click electronic access below)
109

Phylogeography of Pogonomyrmex barbatus and P. rugosus Harvester Ants: A Complex Regional History of Ancient Vicariance and Recent Expansion in Arid- Adapted Insects, and Implications for the Success of Cryptic Hybrid Lineages with GCD

January 2012 (has links)
abstract: Here I present a phylogeographic study of at least six reproductively isolated lineages of harvester ants within the Pogonomyrmex barbatus and P. rugosus species group. The genetic and geographic relationships within this clade are complex: four of the identified lineages are divided into two pairs, and each pair has evolved under a mutualistic system that necessitates sympatry. These paired lineages are dependent upon one another because interlineage matings within each pair are the sole source of hybrid F1 workers; these workers build and sustain the colonies, facilitating the production of the reproductive caste, which results solely from intralineage fertilizations. This system of genetic caste determination (GCD) maintains genetic isolation among these closely related lineages, while simultaneously requiring co-expansion and emigration as their distributions have changed over time. Previous studies have also demonstrated that three of the four lineages displaying this unique genetic caste determination phenotype are of hybrid origin. Thus, reconstructing the phylogenetic and geographic history of this group allows us to evaluate past insights and plan future inquiries in a more complete historical biogeographic context. Using mitochondrial DNA sequences sampled across most of the morphospecies' ranges in the U.S. and Mexico, I employed several methods of phylogenetic and DNA sequence analysis, along with comparisons to geological, biogeographic, and phylogeographic studies throughout the sampled regions. These analyses on Pogonomyrmex harvester ants reveal a complex pattern of vicariance and dispersal that is largely concordant with models of late Miocene, Pliocene, and Pleistocene range shifts among various arid-adapted taxa in North America. / Dissertation/Thesis / M.S. Biology 2012
110

Recrutamento e marcação química de trilha em Atta sexdens rubropilosa (Hymenoptera: Formicidae) sob diferentes fontes de estímulos / Recruitment and chemical-marked trail in Atta sexdens rubropilosa (Hymenoptera: Formicidae) to different stimuli

Fernando Ribeiro Sujimoto 30 January 2014 (has links)
A formação, recrutamento e manutenção de trilhas em formigas cortadeiras do gênero Atta é controlada quimicamente e envolve a participação de diferentes castas. Todavia, são escassos os estudos sobre a dinâmica das castas sob diferentes fontes de estímulos para a colônia, e como isso interfere na deposição de trilhas químicas. O presente trabalho visou compreender a influência de diferentes fontes de estímulos no padrão químico de deposição das trilhas, bem como no comportamento de recrutamento, forrageamento e defesa das operárias em Atta sexdens rubropilosa (Hymenoptera: Formicidae). Os resultados indicaram que houve variação do perfil etológico e alocação de tarefas desempenhadas pelos indivíduos presentes na colônia, de acordo com a fonte de estímulo. Neste caso foram oferecidos uma fonte de estímulo atrativa (\"pétalas de rosas\") e outra de agressividade (\"rainha de outra colônia\"). Além disso, os perfis químicos observados nas trilhas variaram qualitativamente e quantitativamente de acordo com os estímulos oferecidos. Estes dados sugerem que as operárias de A. sexdens rubropilosa seriam capazes de manejar quimicamente seu feromônio de trilha para informar e alterar o comportamento de suas companheiras de ninho, de acordo com a fonte de estímulo em que foram expostas. / Formation, recruitment and maintenance of trail in Atta leaf-cutting ants are chemically controlled and involve participation of different castes. Nevertheless, studies on caste dynamic under different stimuli to the colony are scarce, and how it interferes in the chemical deposition of the trail. This investigation aimed to understand how different source of stimuli influence the chemical pattern of trail marking as well as the recruitment, foraging and defense behavior by workers in Atta sexdens rubropilosa (Hymenoptera: Formicidae). Results indicate variation in the ethological profile and task allocation performed by the colony individuals, according to the stimuli source. In this case, it was offered an attractive stimulus source (\"rose petals\") and an aggressive one (\"other colony queen\"). Moreover, the chemical profiles of the trail varied qualitatively and quantitatively in response to the stimuli they were exposed. These data suggest that A. sexdens rubropilosa workers would be able to chemically manipulate their trail pheromone with aim to inform and alter their nestmate behavior in response to the exposed stimuli source.

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