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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.
21

Autorização e angústia de influência em Winnicott / Authorization and the anxieties of influence in Winnicott

Franco, Wilson de Albuquerque Cavalcanti 30 November 2012 (has links)
O presente trabalho tem como objetivo abordar a forma como se constelaram as angústias de influência para que Winnicott se tornasse o autor que conhecemos em resumo, como se passou a autorização de Winnicott. Suponho que a obra escrita de um autor é a ponta visível de um processo que denominei autorização; a ideia é que todo autor lida, em alguma medida, com angústias associadas à significação que o escrever e/ou o ser-autor assumem para ele. Essa autorização conflui, do ponto de vista assumido aqui, com um reconhecimento e uma afirmação de si perante os pares e as figuras de autoridade que retomam, na chave do grupo de destino da escrita do autor, as questões que a criança tem na fase edípica; tal leitura remonta em muito ao tema da angústia de influência, trabalhada por Harold Bloom, e ao testemunho que Ronald Britton oferece da mesma problemática em relação ao meio psicanalítico. No caso singular de Winnicott, considero o processo de autorização como estando muito relacionado à busca por autenticidade; esta, por sua vez, é entendida como associada ao próprio reconhecimento da existência e da legitimação das formas singulares de afirmação do autor. À sua maneira, Winnicott parece colocar em novos termos a questão em torno da autoridade, na medida em que subverte a problemática da submissão a uma lei maior que funcionaria como tabu a questão passaria por criar uma via própria, singular, por equacionar os imperativos estabelecidos, mas, nesse mesmo gesto de reconhecimento, ele incute uma inovação. A formulação final a que chego, tendo em vista esses aspectos, é que a liberdade de leitura ou a incorporação criativa da tradição ocupam em Winnicott o lugar que a infelicidade cotidiana ou a aceitação da castração assumem em Harold Bloom; na autorização winnicottiana, a liberdade e a idiossincrasia parecem ocupar o lugar que, na triangulação edípica, compete ao pai formulação certamente paradoxal, mas que busca fazer justiça ao pensamento do autor / This work aims to discuss how influence anxieties constellate in the manner through which Winnicott became the author we know, and how we know him (or it) in brief, how Winnicott authorization proceeded. We believe the written oeuvre of an author is the distinguishable tip of the process we named authorization; we understand an author deals, somehow, which anxieties connected to the signification what writing and/or being an author assume to him. This authorization surmounts the process of recognition and self-standing among peers and authority figures, and bring forth in the process of writing for an audience the issues the child undertakes through its oedipical phase; this understanding owes much to the discussions on the anxiety of influence, established around Harold Bloom\'s publications, and to the testimony granted by Ronald Britton about the same topic in regard to his own experience in the psychoanalytical field. In Winnicott\'s case we alleged the authorization process is profoundly related to his search for authenticity, and authenticity, in its turn, has been associated with the recognition of existence and of singular means of existence. In his terms Winnicott seems to have subverted the problematic around the submission to a higher law established as a taboo the problem would be subverted into being that of the search and creation of a particular and singular path equating the manners involved; in that very constitution of the problem the subversion of the classical portrayal of the authorization amidst established and unquestionable authorities, a paradoxical revolution insinuates itself. We claim lastly that in Winnicott\'s work the freedom of thought and the creative incorporation of tradition occupy the place that formerly the everyday misery and the acceptance of castration assumed, e.g. in Harold Bloom\'s work. In Winnicott\'s authorization process freedom and idiosyncrasy occupy the place that, in the classical oedipical triangulation, the father occupies formulation undoubtedly paradoxical, but apparently appropriate to the author\'s theory
22

A criatividade de crianças asmáticas / The asthmatic childrens creativity

Brentan, Cristiane Cintra 14 November 2014 (has links)
A presente pesquisa avaliou a expressão da criatividade de crianças asmáticas, buscando relacioná-la a aspectos de sua personalidade. Existe uma suspeita de que alguns destes aspectos inibem a expressão da criatividade dessas crianças. A asma é um bom exemplo de doença psicossomática. Referências bibliográficas apontam para a observação de um funcionamento atípico do aparelho psíquico dos pacientes somáticos, caracterizado por uma carência funcional das atividades fantasmáticas ligadas à imaginação e à expressão simbólica. Neste contexto, o objetivo do estudo é compreender a relação existente entre a dinâmica da personalidade e a expressão da criatividade de crianças asmáticas. Utilizou-se um método de pesquisa qualitativa. A amostra foi composta de um grupo de quatro crianças, com faixa etária de 7 a 10 anos, portadoras de diagnóstico médico de asma brônquica moderada ou grave. A pesquisa foi realizada em crianças que estavam sendo atendidas no ambulatório de pneumologia pediátrica do Instituto da Criança do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Primeiramente, foi apresentado aos pais o termo de consentimento. Foi feita uma entrevista semiestruturada com os pais e realizados dois encontros com a criança, para a aplicação do Procedimento do Desenho-Estória e do Teste de Criatividade Figural Infantil, finalizando com uma entrevista devolutiva para os pais e para a criança e totalizando quatro encontros. Dois conceitos distintos de criatividade foram abordados na pesquisa: a criatividade a que se refere a teoria winnicottiana, teoria escolhida para fazer a leitura psicológica dos sujeitos de pesquisa, e a criatividade a que se refere o Teste de Criatividade Figural Infantil. Como resultado da pesquisa, percebeu-se que não foi possível encontrar um perfil psicológico da criança asmática, visto que as quatro crianças da amostra apresentaram aspectos da personalidade muito peculiares, havendo também peculiaridades nas expressões de suas criatividades. Por outro lado, foi possível perceber a relação individual da personalidade de cada criança com a expressão de sua criatividade, podendo-se fazer uma comparação entre elas. O estudo apontou que, em geral, a criança asmática consegue expressar sua criatividade, não corroborando estudos anteriores ligados à psicossomática. Além disto, a presente pesquisa deu indícios de que o indivíduo que consegue vivenciar o espaço potencial de maneira saudável pode apresentar um alinhamento percebido entre os dois conceitos de criatividade abordados no estudo / The present study has evaluated the creativity expression of children with asthma, seeking to relate it to aspects of their personality. There is a suspicion that some of these aspects inhibit the expression of these children creativity. Asthma is a good example of psychosomatic illness. References point to the observation of atypical functioning of somatic patients psychic apparatus, described as a functional deficiency of the ghostly activities related to imagination and symbolic expression. In this context, the studys goal is to understand the relationship between the personality dynamics and the asthmatic childrens creativity. There was adopted a qualitative research method. The sample consisted of a four children group, aged 7-10 years, with a diagnosis of moderate or severe bronchial asthma. The field research was performed with children who have been treated at the pediatric pulmonology department at Instituto da Criança do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. At first, there was submitted a consent form to the parents. Then, there were performed a semi-structured interview with the parents and two meetings with each child, dedicated to the Procedure of Drawing-Story and the Children\'s Creativity Figural Test, ending with a feedback interview with parents and child and totalizing four meetings with each research subject. Two distinct concepts of creativity were addressed in this study: creativity referred to Winnicott\'s theory, theory chosen to make the psychological reading of the research subjects, and creativity referred to Test of Creativity Figural Child. A result of the research is that it was not possible finding a psychological profile of the asthmatic children as the four children in the sample had very peculiar aspects of personality, with peculiarities in the expressions of their creativity as well. On the other hand, there was observed an individual relationship of each childs personality with the expression of their creativity, reasonably allowing making a comparison between them. The study found that, in general, asthmatic children can express their creativity, not confirming previous studies related to psychosomatic. Moreover, this research has hinted that an individual who healthily experiences the potential space could present a perceived alignment between both creativity concepts addressed in the study
23

Entre a forja e a bigorna: a escrita de singularização do psicanalista Gilberto Safra / Between the forge and the anvil: the singularization writing of psychoanalyst Gilberto Safra

Karina Schmidt Brancher 29 June 2012 (has links)
Ao longo da dissertação, para dar forma e legitimidade à intuição e à experiência emocional e intelectiva que a autora teve com a obra do psicanalista brasileiro Gilberto Safra, foi empreendido o esforço de fabricar uma interpretação que acontecesse como reposta a esta obra. Para tanto, propusemos uma leitura pormenorizada (o que inclui a leitura sistemática e a leitura próxima desconstrutiva) de dois livros de Safra: Momentos Mutativos em Psicanálise, sua tese de doutorado e A Face Estética do Self, sua tese de livre docência. Este recorte da obra se ancorou na hipótese de que haveria algo na construção do pensamento psicanalítico de Safra que se modificou consideravelmente entre estes dois momentos de sua trajetória pessoal, autoral e na sua formação como analista. Em resposta a estas questões, uma leitura entrelaçada das teses que compõem seu pensamento psicanalítico com suas condições de possibilidade nos levou a compreender que a escrita de Safra deixa entrever o tortuoso movimento de busca de um analista por sua morada conceitual, ética e estética. O que está em jogo é sempre o processo de singularização: do analista, do paciente e das possibilidades de se fazer teoria e clínica psicanalíticas nos tempos atuais / This dissertation, in order to shape and legitimize the authors intuition, and emotional and intellectual experience with the works of Brazilian psychoanalyst Gilberto Safra, strived to create an interpretation that could stand as answer to said works. As such, we proposed a detailed reading (which includes a systematic and then deconstructive reading) of two of Safras books: Mutative Moments in Psychoanalysis, his doctoral thesis, and The Aesthetic Face of the Self, his associate professorship thesis. This partial selection of his work is anchored on the hypothesis that there would be something in the construction of Safras psychoanalytical thinking which had been considerably altered between these two points in his personal and authorial trajectory, and his training as an analyst. In response to these questions, an interwoven reading of these theses which make up his psychoanalytical thought, with their conditions of possibility, led us to understand that Safras writing allows us to glimpse an analysts tortuous path in search of his conceptual, ethical and aesthetic references. Whats at stake is always the singularization process: of the analyst, the patient and the possibilities of creating psychoanalytical theory and doing psychoanalytical clinic work in current times
24

Autorização e angústia de influência em Winnicott / Authorization and the anxieties of influence in Winnicott

Wilson de Albuquerque Cavalcanti Franco 30 November 2012 (has links)
O presente trabalho tem como objetivo abordar a forma como se constelaram as angústias de influência para que Winnicott se tornasse o autor que conhecemos em resumo, como se passou a autorização de Winnicott. Suponho que a obra escrita de um autor é a ponta visível de um processo que denominei autorização; a ideia é que todo autor lida, em alguma medida, com angústias associadas à significação que o escrever e/ou o ser-autor assumem para ele. Essa autorização conflui, do ponto de vista assumido aqui, com um reconhecimento e uma afirmação de si perante os pares e as figuras de autoridade que retomam, na chave do grupo de destino da escrita do autor, as questões que a criança tem na fase edípica; tal leitura remonta em muito ao tema da angústia de influência, trabalhada por Harold Bloom, e ao testemunho que Ronald Britton oferece da mesma problemática em relação ao meio psicanalítico. No caso singular de Winnicott, considero o processo de autorização como estando muito relacionado à busca por autenticidade; esta, por sua vez, é entendida como associada ao próprio reconhecimento da existência e da legitimação das formas singulares de afirmação do autor. À sua maneira, Winnicott parece colocar em novos termos a questão em torno da autoridade, na medida em que subverte a problemática da submissão a uma lei maior que funcionaria como tabu a questão passaria por criar uma via própria, singular, por equacionar os imperativos estabelecidos, mas, nesse mesmo gesto de reconhecimento, ele incute uma inovação. A formulação final a que chego, tendo em vista esses aspectos, é que a liberdade de leitura ou a incorporação criativa da tradição ocupam em Winnicott o lugar que a infelicidade cotidiana ou a aceitação da castração assumem em Harold Bloom; na autorização winnicottiana, a liberdade e a idiossincrasia parecem ocupar o lugar que, na triangulação edípica, compete ao pai formulação certamente paradoxal, mas que busca fazer justiça ao pensamento do autor / This work aims to discuss how influence anxieties constellate in the manner through which Winnicott became the author we know, and how we know him (or it) in brief, how Winnicott authorization proceeded. We believe the written oeuvre of an author is the distinguishable tip of the process we named authorization; we understand an author deals, somehow, which anxieties connected to the signification what writing and/or being an author assume to him. This authorization surmounts the process of recognition and self-standing among peers and authority figures, and bring forth in the process of writing for an audience the issues the child undertakes through its oedipical phase; this understanding owes much to the discussions on the anxiety of influence, established around Harold Bloom\'s publications, and to the testimony granted by Ronald Britton about the same topic in regard to his own experience in the psychoanalytical field. In Winnicott\'s case we alleged the authorization process is profoundly related to his search for authenticity, and authenticity, in its turn, has been associated with the recognition of existence and of singular means of existence. In his terms Winnicott seems to have subverted the problematic around the submission to a higher law established as a taboo the problem would be subverted into being that of the search and creation of a particular and singular path equating the manners involved; in that very constitution of the problem the subversion of the classical portrayal of the authorization amidst established and unquestionable authorities, a paradoxical revolution insinuates itself. We claim lastly that in Winnicott\'s work the freedom of thought and the creative incorporation of tradition occupy the place that formerly the everyday misery and the acceptance of castration assumed, e.g. in Harold Bloom\'s work. In Winnicott\'s authorization process freedom and idiosyncrasy occupy the place that, in the classical oedipical triangulation, the father occupies formulation undoubtedly paradoxical, but apparently appropriate to the author\'s theory
25

A criatividade de crianças asmáticas / The asthmatic childrens creativity

Cristiane Cintra Brentan 14 November 2014 (has links)
A presente pesquisa avaliou a expressão da criatividade de crianças asmáticas, buscando relacioná-la a aspectos de sua personalidade. Existe uma suspeita de que alguns destes aspectos inibem a expressão da criatividade dessas crianças. A asma é um bom exemplo de doença psicossomática. Referências bibliográficas apontam para a observação de um funcionamento atípico do aparelho psíquico dos pacientes somáticos, caracterizado por uma carência funcional das atividades fantasmáticas ligadas à imaginação e à expressão simbólica. Neste contexto, o objetivo do estudo é compreender a relação existente entre a dinâmica da personalidade e a expressão da criatividade de crianças asmáticas. Utilizou-se um método de pesquisa qualitativa. A amostra foi composta de um grupo de quatro crianças, com faixa etária de 7 a 10 anos, portadoras de diagnóstico médico de asma brônquica moderada ou grave. A pesquisa foi realizada em crianças que estavam sendo atendidas no ambulatório de pneumologia pediátrica do Instituto da Criança do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. Primeiramente, foi apresentado aos pais o termo de consentimento. Foi feita uma entrevista semiestruturada com os pais e realizados dois encontros com a criança, para a aplicação do Procedimento do Desenho-Estória e do Teste de Criatividade Figural Infantil, finalizando com uma entrevista devolutiva para os pais e para a criança e totalizando quatro encontros. Dois conceitos distintos de criatividade foram abordados na pesquisa: a criatividade a que se refere a teoria winnicottiana, teoria escolhida para fazer a leitura psicológica dos sujeitos de pesquisa, e a criatividade a que se refere o Teste de Criatividade Figural Infantil. Como resultado da pesquisa, percebeu-se que não foi possível encontrar um perfil psicológico da criança asmática, visto que as quatro crianças da amostra apresentaram aspectos da personalidade muito peculiares, havendo também peculiaridades nas expressões de suas criatividades. Por outro lado, foi possível perceber a relação individual da personalidade de cada criança com a expressão de sua criatividade, podendo-se fazer uma comparação entre elas. O estudo apontou que, em geral, a criança asmática consegue expressar sua criatividade, não corroborando estudos anteriores ligados à psicossomática. Além disto, a presente pesquisa deu indícios de que o indivíduo que consegue vivenciar o espaço potencial de maneira saudável pode apresentar um alinhamento percebido entre os dois conceitos de criatividade abordados no estudo / The present study has evaluated the creativity expression of children with asthma, seeking to relate it to aspects of their personality. There is a suspicion that some of these aspects inhibit the expression of these children creativity. Asthma is a good example of psychosomatic illness. References point to the observation of atypical functioning of somatic patients psychic apparatus, described as a functional deficiency of the ghostly activities related to imagination and symbolic expression. In this context, the studys goal is to understand the relationship between the personality dynamics and the asthmatic childrens creativity. There was adopted a qualitative research method. The sample consisted of a four children group, aged 7-10 years, with a diagnosis of moderate or severe bronchial asthma. The field research was performed with children who have been treated at the pediatric pulmonology department at Instituto da Criança do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo. At first, there was submitted a consent form to the parents. Then, there were performed a semi-structured interview with the parents and two meetings with each child, dedicated to the Procedure of Drawing-Story and the Children\'s Creativity Figural Test, ending with a feedback interview with parents and child and totalizing four meetings with each research subject. Two distinct concepts of creativity were addressed in this study: creativity referred to Winnicott\'s theory, theory chosen to make the psychological reading of the research subjects, and creativity referred to Test of Creativity Figural Child. A result of the research is that it was not possible finding a psychological profile of the asthmatic children as the four children in the sample had very peculiar aspects of personality, with peculiarities in the expressions of their creativity as well. On the other hand, there was observed an individual relationship of each childs personality with the expression of their creativity, reasonably allowing making a comparison between them. The study found that, in general, asthmatic children can express their creativity, not confirming previous studies related to psychosomatic. Moreover, this research has hinted that an individual who healthily experiences the potential space could present a perceived alignment between both creativity concepts addressed in the study
26

Evaluation of transport relative to the tidal mixing front on Southern Georges Bank

Katrein, Jody M. (Jody Marie), 1977- January 2001 (has links)
Thesis (S.M.)--Joint Program in Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Ocean Engineering and the Woods Hole Oceanographic Institution), September 2001. / Includes bibliographical references (leaves 65-67). / As part of Phase III of the U.S. GLOBEC Georges Bank program, drogued drifters and dye tracer were released into the pycnocline on the southern flank of Georges Bank to measure advective and diffusive transport relative to the tidal mixing front in May 1999. Potential density measurements placed the tidal mixing front around the 50-55 m isobath on the southern flank. Drogued drifter movement relative to the front was on the order of the drifter's slip velocity and therefore did not support the existence of a mean, advective flow. No movement relative to the front of the dye patch center of mass also indicated a lack of advective flow. Diffusive transport did occur as the dye patch spread laterally both toward and away from the front much as would be predicted by the diffusion relationship of Okubo (1971), who summarized diffusion experiments in the surface ocean. The dye did not spread symmetrically, but was rather elongated along the isobaths. This can be attributed to vertical shear in the along-isobath current that was measured by the shipboard ADCP. / by Jody M. Katerin. / S.M.
27

Horizontal linear array sensor localization and preliminary coherence measurements from the 2001 ASIAEX South China Sea experiment / Horizontal linear array sensor localization and preliminary coherence measurements from the 2001 Asian Seas International Acoustic Experiment SCS experiment

Schroeder, Theodore Herbert, 1967- January 2002 (has links)
Thesis (S.M.)--Joint Program in Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Ocean Engineering and the Woods Hole Oceanographic Institution), 2002. / Includes bibliographical references (p. 105). / This thesis examines data collected in the South China Sea (SCS) component of the 2001 Asian Seas International Acoustic Experiment (ASIAEX), where a fixed Horizontal Linear Array (HLA) was deployed to study transverse array coherence in a coastal environment. Arrays obtain their gain and directivity by coherently adding the energy that impinges on them. Therefore, to maximize the efficiency of an array, the size of the aperture over which the signal remains coherent needs to be determined. Scattering of sound by the ocean environment, especially in coastal areas, reduces the coherence of acoustic signals, and thereby limits the useful aperture of an acoustic array. During ASIAEX, a horizontal linear array was deployed on the continental shelf of the South China Sea in order to directly measure the acoustic coherence in a coastal environment. 224 Hz and 400 Hz sources were placed on the continental slope to provide an up slope propagation path and a 400 Hz source was placed on the shelf to provide an along shelf propagation path. This thesis analyzes one day of transmissions from these three sources and gives the first look at coherence lengths of the HLA determined by sensor-to-sensor correlations. To achieve this, the thesis analyzes continuous time series data from the Long Base Line (LBL) navigation system and two days of light bulb drops to provide array sensor localization. Accurate sensor positions are needed to determine the correlation versus sensor separation distance and ultimately the array coherence length. / by Theodore Herbert Schroeder. / S.M.
28

Estimating Gulf of Maine zooplankton distributions using multiple frequency acoustic, video and environmental data

Warren, Joseph David January 2001 (has links)
Thesis (Ph.D.)--Joint Program in Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Ocean Engineering and the Woods Hole Oceanographic Institution), February 2001. / Includes bibliographical references (p. 211-219). / This thesis develops methods useful for estimating zooplankton distributions in the field by combining acoustic scattering models and an integrated set of field data. The accuracy of existing scattering models for fluid-like and elastic-shelled animals is determined by analysis of scattering data from individual animals in a laboratory tank. Results indicate that simple two-ray scattering models are accurate and allow predictions of size or orientation of an animal to be made for certain animal orientations. A scattering model for gas-bearing zooplankton is compared with in situ multiple frequency acoustic measurements from siphonophores. Estimates of the numerical density of these animals are made using echo integration data from a scientific echo-sounder. Multiple frequency acoustic scattering data from a survey of an internal wave are analyzed to determine the contributions from biological and physical sources. Net tow data provide information about biological scatterers while temperature and salinity profiles are used with a theoretical scattering model to predict contributions from physical sources. Results indicate that scattering from physical sources is comparable to that from biological sources in certain regions and that scattering spectra may be used to distinguish these sources. Improved estimates of biomass from acoustic scattering data were made by accounting for the scattering contributions from physical sources. This is the first work to quantify the scattering contributions from biological and physical sources of scattering in a field study. / by Joseph David Warren. / Ph.D.
29

Design considerations for engineering Autonomous Underwater Vehicles / Design considerations for engineering AUVs

Shah, Vikrant P. (Vikrant Pankaj) January 2007 (has links)
Thesis (S.M.)--Joint Program in Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Mechanical Engineering; and the Woods Hole Oceanographic Institution), 2007. / Includes bibliographical references (p. 85-89). / Autonomous Underwater Vehicles (AUVs) have been established as a viable tool for Oceanographic Sciences. Being untethered and independent, AUVs fill the gap in Ocean Exploration left by the existing manned submersible and remotely operated vehicles (ROV) technology. AUVs are attractive as cheaper and efficient alternatives to the older technologies and are breaking new ground in many applications. Designing an autonomous vehicle to work in the harsh environment of the deep ocean comes with its set of challenges. This paper discusses how the current engineering technologies can be adapted to the design of AUVs. Recently, as the AUV technology has matured, we see AUVs being used in a variety of applications ranging from sub-surface sensing to sea-floor mapping. The design of the AUV, with its tight constraints, is very sensitive to the target application. Keeping this in mind, the goal of this thesis is to understand how some of the major issues affect the design of the AUV. This paper also addresses the mechanical and materials issues, power system design, computer architecture, navigation and communication systems, sensor considerations and long term docking aspects that affect AUV design. With time, as the engineering sciences progress, the AUV design will have to change in order to optimize its performance. Thus, the fundamental issues discussed in this paper can assist in meeting the challenge of maintaining AUV design on par with modern technology. / by Vikrant P. Shah. / S.M.
30

Life cycle evolution and systematics of Campanulariid hydrozoans

Govindarajan, Annette Frese, 1970- January 2004 (has links)
Thesis (Ph. D.)--Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Biology; and, the Woods Hole Oceanographic Institution), 2004. / Includes bibliographical references. / The purpose of this thesis is to study campanulariid life cycle evolution and systematics. The Campanulariidae is a hydrozoan family with many life cycle variations, and provide an excellent model system to study life cycle evolution. Additionally, the unique campanulariid Obelia medusae may have been "re-invented" from ancestors without medusae. Chapter 1 reviews campanulariid life cycles and taxonomy. Chapter 2 presents a phylogeny based on 18S rDNA, calmodulin, 16S rDNA and cytochrome c oxidase I (COI). Ancestral life cycles are reconstructed using parsimony. Medusa loss is common, and Obelia may derive from ancestors with typical medusae. Taxonomic results are discussed in Chapter 3. Billardia, a nominal campanulariid, appears phylogenetically distant, while Bonneviella spp. (Bonneviellidae), are nested within the Campanulariidae. Campanulariid genera are not monophyletic. Orthopyxis integra and Clytia gracilis may represent cryptic species, while Obelia longissima may be cosmopolitan. Chapter 4 investigates Obelia geniculata phylogeography. Japanese and North Atlantic 16S rDNA and COI sequences are calibrated against the opening of the Bering Strait. Substitution rates are faster than in anthozoans and comparable to non-cnidarian invertebrates. Comparison of Pacific and Atlantic sequences suggests cryptic species exist. Finally, hydroids in New Brunswick, Canada and Iceland may have survived the last glaciation. / by Annette Frese Govindarajan. / Ph.D.

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