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Fatores biopsicossociais no envelhecimento e percepção da qualidade de vida do idoso / Biopsychosocial factors associated with ageing and elders perception of life qualityAlberte, Josiane Souza Pinto 14 August 2018 (has links)
Orientador: Maria Elena Guariento / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-14T03:48:42Z (GMT). No. of bitstreams: 1
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Previous issue date: 2009 / Resumo: Em vista da relevância que adquire o parâmetro qualidade de vida entre os indivíduos que estão envelhecendo, desenvolveu-se este trabalho que tem por objetivo avaliar e comparar os fatores que interferem na percepção da qualidade de vida (PQV) de dois grupos distintos de idosos que requerem um suporte institucional de duas instituições diferentes. Foram avaliados cento e seis pacientes entre sessenta e oitenta anos de ambos os sexos. Entre esses, 48 eram acompanhados no Ambulatório de Geriatria (AG) do Hospital de Clínicas da Faculdade de Ciências Médicas da UNICAMP. O outro grupo constituiu-se de 58 sujeitos do Grupo da Terceira Idade do Serviço Social do Comércio (SESC) de Campinas. Os instrumentos utilizados foram: ficha de avaliação de dados sócio-demográficos, prática de atividade física, doenças / estados mórbidos, número de medicamentos e fatores estressantes auto-relatados, bem como a percepção da qualidade de cada um dos ciclos de vida (infância, adolescência, idade adulta e velhice); International Neuropsychiatric Interview (MINI); questionário de qualidade de vida - WHOQOL-bref. Os resultados mostraram que a melhor percepção da qualidade de vida no domínio físico relacionou-se à prática de atividade física, ao não relato de dores, referência à boa infância e boa velhice, uso regular de menor quantidade de medicamentos. No domínio psicológico os idosos com melhor avaliação da qualidade de vida foram os que não apresentavam transtorno distímico, relatavam boa adolescência e velhice, usavam menor número de medicamentos e se consideravam felizes. No domínio social, a maior pontuação para qualidade de vida relacionou-se a: considerar-se feliz, não ter evidência de hipomania, negar solidão como evento estressante e referir boa adolescência. Quanto ao domínio ambiental, a referência à melhor qualidade de vida associou-se a: referir boa infância e velhice, maior nível de escolaridade e negar doença como evento estressante. Esses achados abrem para uma nova avaliação dos conceitos atuais sobre a velhice e processo de envelhecimento considerando-se os fatores que se associam a uma melhor percepção da qualidade de vida entre os idosos. Nesse estudo, verificou-se que a percepção da qualidade dos ciclos de vida, o uso de medicamentos, a prática de atividade física, a evidência de distimia e hipomania, o nível de escolaridade e a referência a dores, solidão e doença como eventos estressantes tinham interferência na percepção da qualidade de vida dos idosos avaliados / Abstract: Considering the relevance of life quality among aging individuals, this study has been developed with the aim to compare factors that interfere with the perception of lifequality (PLQ) between two distinct groups of elderly requiring the support of two different institutions. One hundred and six pacients have been assessed between ages sixty and eighty of both sexes. Among these, forty eight were followed closely by the Geriatric Ambulatory of the Hospital das Clínicas at the Faculty of Medical Sciences - UNICAMP. The other group consisted of fifty eight subjects from the group of elderly of the Serviço Social do Comércio (SESC) from Campinas. The instruments used were: a valuation card of sociodemographic data, ie, physical activity, diseases/morbid states, number of medicines taken, stress factors, as well as the perception of their life quality in each of the cycles of life, such as infancy, adolescence, adulthood and old age; The International Neuropsychiatric Interview (MINI); questionnaire on life quality - WHOQOL - BREF. The results showed that the best perception of quality of life in the physical domain were related to physical activity and absence of pain, a good activity and good age, regular minor use of medication. In the psychological area of the elderly, the best life quality valuation was of those who did not present distimic disorder, reported a happy adolescence and old age, used less medication, and considered themselves happy. In the social sphere the best valuation of life quality was related to considering oneself as happy, presenting an absence of hipomania, no stress on account of loneliness, a good adolescence. As for the environmental domain, the best quality of life was associated with a good childhood and old age, a higher level of education, no disease as stressful event. These findings lead to a new appraisal of the concepts on old age and the aging process, considering the possibilities associated with a better life quality for the elderly. In this study the perception of the life cycles'quality, the use of medication, physical activity, evidence of distimia and hipomania, level of education, reference to pains, solitude and disease as stressful events, interfered with the life quality of the valuated elderly / Doutorado / Saude Mental / Doutor em Ciências Médicas
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Docência em Artes Visuais: continuidades e descontinuidades na (re) construção da trajetória profissional. / Teaching Visual Arts: continuities and discontinuities in the (re) construction of the professional career.Biasoli, Carmen Lúcia Abadie 17 September 2009 (has links)
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Previous issue date: 2009-09-17 / The present research discusses the problematic of the teaching career in Visual Arts based on the study of professional life cycle, that is, the vital cycle through which the teachers face. Thus, it aimed at investigating the continuities and discontinuities in the (re) construction of teachers professional careers in Visual Arts, defending the idea that significant aspects of both personal and professional life and the teaching moment lived by the teachers interfere both in the construction of this career as well as in a better
understanding of the role of the teacher and, consequently, his / her teaching performance. In the field of Visual Arts teaching, this thesis equally reconstructs the history of institutions responsible for the teaching of Arts in our country, focusing more specifically the present situation of the Instituto de Artes e Design (Arts and Design Institute) from the Federal University of Pelotas (UFPel), which was opened back in 1949. The thesis is based in different researches about biographical data, including the ones
which concern the different teacher s career phases (centered in the years of professional experience), and the life cycles, indicating the personal dimension as
fundamental in the process by which the teachers build their careers and make their work dynamic, making it clear that the professional improvement is associated to the personal improvement, or is also part of it. Besides this, there are contributions from authors who investigate the teaching activity, specially the ones involved with the professionalization, the professional development and the teacher s knowledge, as well as investigators who analyze the school as a culture producer. The methodological approach is biographic-narrative, which enables the teachers to talk
about what they know and do, what they did or what they could or should do, that is, it makes possible to make explicit the past dimensions which have an influence on the
present situations and its projection into expected action forms. The teachers who participated in the research teach in city public schools in Pelotas in the area of Visual
Arts, all having graduated at IAD. The study takes a quanti-qualitative character, as it combines the questionnaire with interviews. The questionnaire involved 40 teachers and
enabled to know characteristics and expectations common to the people as a whole. The interviewed was made with 7 teachers, graduated in different phases of the teaching course (according to changes in the educational legislation) and with distinct teaching experience, permitting to understand aspects related to school history; the
choice of the career with their determinant factors and expectations; academic history and their influences; remembrances and teaching practical education; teaching career, within its initial years; whether the fact of being a man / woman affected his / her career; the teaching experience, previous and present. For a better understanding of the teaching career, biographical paths were created based on the analysis of the interviews, here so-called biopaths. Another element used to complement the interviews
and the analysis of the biographical data were Travelling Images of Art pieces asked by the teachers, chosen by them in order to express the present moment which they have been facing. For the elaboration of phases, the starting point was the principle that the years of career are meaningful to define the beginning of the first phase, called impact (1-6
years), but they were not standards for its end, because the events faced by the teachers, both at schools as well as in their personal lives, were significant for a change of phase. The closeness to the second phase, the personalization one (7-12 years), was justified because the teachers defined a personal teaching style to teach Visual Arts for groups of different levels and schools with different realities, which demands time and maturity, without discharging a faster change provoked by one or another type of event, a critical moment faced by the teacher. The phase of alternation (13-18 years) corresponded to a period in which the teaching experience enabled the teacher to better
understand the educational and the teaching system, what he / she can or cannot do, what he / she wants to do or not, the teacher gave him /herself the chance to choose.
Finally the fact of being close to the end of the career determined the so-called individualization phase (19-25 years), responsible for the distance between the teacher
and the educational problems and the search for personal satisfaction. Therefore, the teaching years are considered meaningful in the professional career, but they are not the ones which define the phases, as the narratives from the teachers prove that the phases constantly mix - or not and one does not place away nor eliminates the possibility of another. Finally, the modifications in the life phases of
teachers are caused by the conditions of determined time and places, having occurred due to the opportunities and limitations dealt by each one of them; the crisscrossing of
personal histories and the professional careers in these different moments and places configure a singularity in the teaching practice of these teachers. Although all have gone
through, in a general way, similar phases in their teaching careers, it was evident that each one have their own and unique life experience and professional career, each with
a specific subjective experience, each one of them is unique.
To end, it can be said that the understanding of the life cycles, through the phases of the teaching career, crisscrossing personal histories and professional careers in different places and moments of the teaching practice, enables thinking about alternatives and motivating innovation proposals for the initial and continuing teacher s education. / Esta pesquisa discute a problemática da profissão docente em Artes Visuais a partir do estudo do ciclo de vida profissional, ou seja, do ciclo vital pelo qual passam os professores. Assim, teve como objetivo investigar as continuidades e escontinuidades na (re) construção da trajetória profissional de docentes de Artes Visuais, defendendo a idéia de que aspectos significativos da vida pessoal e profissional e o momento docente em que se encontram os professores interferem tanto na construção dessa trajetória quanto para uma melhor compreensão da pessoa do professor e, como conseqüência, da sua atuação docente. No campo do ensino das Artes Visuais, esta tese igualmente reconstrói a história das instituições responsáveis pelo ensino da Arte em nosso país, enfocando mais precisamente o caso do atual Instituto de Artes e Design (IAD) da Universidade Federal de Pelotas (UFPel), cuja criação remonta a 1949. A tese está assentada em diferentes pesquisas sobre trajetórias biográficas, incluindo
as que abordam as fases da carreira do professor (centradas nos anos de experiência profissional), e os ciclos de vida, indicando a dimensão pessoal como fundamental no processo pelos quais os professores se constroem e dinamizam seu trabalho, deixando claro que o aperfeiçoamento profissional está associado ao desenvolvimento pessoal, ou faz parte dele. Ademais, são trazidas contribuições de autores que investigam o trabalho docente, especialmente os que tratam da profissionalização, do desenvolvimento profissional e dos saberes docentes, bem como de investigadores que analisam a escola como produtora de cultura. A abordagem metodológica é a biográfico-narrativa, que possibilita aos professores falarem sobre o que conhecem e fazem, o que faziam ou o que poderiam ou deveriam fazer, ou seja, permite a explicitação das dimensões do passado que pesam sobre as
situações atuais e sua projeção em formas desejáveis de ação. Os professores que participaram da pesquisa exercem a docência na rede municipal de Pelotas e atuam na
área de Artes Visuais, todos formados pelo IAD. O estudo assume um caráter quantiqualitativo, ao combinar questionário com entrevista. O questionário envolveu 40
professores e possibilitou conhecer características e expectativas formativas comuns no coletivo. A entrevista foi realizada com 7 professores, formados em diferentes etapas do
curso de formação docente (conforme as mudanças da legislação educacional) e com distintos tempos de atuação no magistério, permitindo compreender aspectos relativos
à escolarização; escolha da profissão com seus fatores determinantes e expectativas; trajetória acadêmica com suas influências; lembranças e formação prática de ensino;
carreira docente, com seus primeiros anos; se o fato de ser mulher/homem afetou a carreira; exercício da docência, anterior e atual. Para melhor compreensão da trajetória
docente, a partir da análise das entrevistas foram criados os caminhos biográficos, aqui denominados de biovias. Outro elemento usado para complementar as entrevistas e
análise de dados biográficos foram Imagens Viajantes de obras de Arte solicitadas aos professores, escolhidas por eles para significar o momento atual em que estão vivendo.
Para a elaboração das fases partiu-se do princípio de que os anos de carreira são significativos para definir o início da primeira fase, denominada de impacto (1-6 anos),
mas não foram balizadores do seu término, porque os acontecimentos vividos pelos professores, tanto na escola quanto na vida pessoal, foram determinantes para uma
mudança de fase. Já a aproximação da segunda fase, a de personalização (7-12 anos), justificou se porque os professores definiram um estilo pessoal de ensinar Artes
Visuais para turmas de níveis diversificados e escolas com realidades diferentes, o que requer tempo e maturidade, sem descartar uma mudança mais rápida provocada por um ou outro tipo de acontecimento, um momento crítico enfrentado pelo professor. A fase de alternância (13-18 anos) correspondeu a um período no qual o tempo de atuação possibilitou ao professor uma maior compreensão do sistema educacional e da docência, do que pode ou não, do que quer ou não fazer, o professor permitiu-se optar.
Já a proximidade com o final da carreira determinou a fase de individualização (19-25 anos), responsável pelo distanciamento do professor dos problemas educacionais e
pela busca de satisfação pessoal. Deste modo, os anos de docência são considerados significativos na trajetória
profissional, mas não são definidores das fases, pois as narrativas dos professores comprovam que as fases se mesclam constantemente - ou não - e uma não afasta nem
elimina a possibilidade de outra. Portanto, as modificações nas fases da vida dos professores são ocasionadas pelas condições de tempo e lugar determinados, ocorreram pelas oportunidades e limitações vividas por cada um deles; o
entrecruzamento das histórias pessoais e das trajetórias profissionais nesses diferentes espaços e tempos configuram uma singularidade na prática docente desses professores. Embora todos tenham passado, de um modo geral, por fases similares da carreira docente, ficou evidente que cada um tem uma história de vida e trajetória profissional singular, cada um tem uma trajetória subjetiva específica, cada um deles é
único. Por fim, pode-se dizer que a compreensão dos ciclos de vida, através das fases da carreira docente, entrecruzando histórias pessoais e trajetórias profissionais em diferentes espaços e tempos da prática docente, possibilita pensar alternativas e incentivar propostas de inovação para a formação docente inicial e continuada.
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An Agent-Based Model of Institutional Life-CyclesWäckerle, Manuel, Rengs, Bernhard, Radax, Wolfgang January 2014 (has links) (PDF)
We use an agent-based model to investigate the interdependent dynamics
between individual agency and emergent socioeconomic structure, leading to institutional
change in a generic way. Our model simulates the emergence and exit of institutional
units, understood as generic governed social structures. We show how endogenized trust
and exogenously given leader authority influences institutional change, i.e., diversity in
institutional life-cycles. It turns out that these governed institutions (de)structure in cyclical
patterns dependent on the overall evolution of trust in the artificial society, while at the same
time, influencing this evolution by supporting social learning. Simulation results indicate
three scenarios of institutional life-cycles. Institutions may, (1) build up very fast and
freeze the artificial society in a stable but fearful pattern (ordered system); (2) exist only for
a short time, leading to a very trusty society (highly fluctuating system); and (3) structure
in cyclical patterns over time and support social learning due to cumulative causation of
societal trust (complex system).
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Perheenlisäys isien kokemana – fenomenologinen tutkimusMesiäislehto-Soukka, H. (Helinä) 17 May 2005 (has links)
Abstract
The purpose of this research is to describe fathers' experiences in the context of family life after the birth of a baby. The approach to the topic is phenomenological. The data were collected in two stages from partners or husbands of women who had given birth to a child in a central hospital. First, 30 fathers were interviewed in 1999, three months after the child's birth. Three years later, in the spring and summer of 2002, 15 out of the 30 fathers were selected for a second interview on the basis of their ample talking and subsequent ability to express their experiences best. There were both first-timers and more experienced fathers among the informants. The open, conversational interviews yielded 650 pages of material, which was analyzed by the phenomenological method developed by Amadeo Giorgi and further developed by Juha Perttula in Finland.
The study produced 15 individual situational meaning structures concerning the fathers' experiences. These individual meaning structures were used to create a general situational meaning structure concerning the fathers' experiences of family life after the birth of a baby. The family life after the birth of a baby involved the meaning of obtaining and building a home. It produced joy, happiness, but also responsibility and concern. The wife's pregnancy, the delivery and the new child entailed growing as a father and developing as a man. It also called for adjusting to the changed situation. The fathers' experiences of family life after the birth of a baby were influenced by their own childhood experiences and upbringing, by their growth into fatherhood and by their actions as fathers. The atmosphere of the home was based on the relationship between the husband and wife. The fathers appreciated the professionals' way of meeting and caring for the expectant family, but felt that the approach was mother-oriented and ignored the fathers. / Tiivistelmä
Tutkimuksessa kuvaillaan isien kokemuksia perheenlisäyksen yhteydessä. Tutkimuksen lähestymistapa on fenomenologinen. Keräsin keskussairaalassa synnyttäneiden äitien avo- tai aviomiehiltä aineiston kahdessa eri vaiheessa: vuonna 1999 haastattelin kolmen kuukauden kuluttua synnytyksestä 30:tä perheenlisäyksen kokenutta isää ja kolmen vuoden kuluttua ensimmäisestä haastattelusta valitsin heidän keskuudestaan 15 isää, jotka puhuivat riittävästi ja ilmaisivat näin kokemuksiaan parhaiten. Nämä isät haastattelin kevään ja kesän 2002 aikana uudelleen. Isät olivat vaihtelevasti joko ensimmäisen lapsen isiä, tai joissakin perheissä oli useita lapsia. Tutkimusaineistona olivat isien avoimet keskustelunomaiset haastattelut, joita kertyi kaikkiaan 650 sivua. Analysoin aineiston Amadeo Giorgin kehittämällä ja Juha Perttulan edelleen kehittämällä analyysimenetelmällä.
Tämän tutkimuksen tuloksena muodostui 15 yksilökohtaista situationaalista merkitysrakennetta isien kokemuksista perheenlisäyksen yhteydessä. Niiden avulla tämän tutkimuksen tuloksena muodostettiin yleinen situationaalinen merkitysrakenne isien kokemuksista perheenlisäyksen yhteydessä. Koettu perheenlisäys merkitsi isille kodin rakentumista ja rakentamista. Se tuotti iloa, onnea ja myös vastuuta sekä huolta. Vaimon raskaus, synnytys ja uusi lapsi merkitsivät kasvamista isänä ja kehittymistä miehenä. Perheenlisäys merkitsi sopeutumista uuteen muuttuneeseen tilanteeseen. Isien kokemuksiin perheenlisäyksestä vaikuttivat lapsuuden kokemukset, isäksi kasvaminen, kasvatus ja isänä toimiminen. Miehen ja vaimon välinen parisuhde oli perusta kodin ilmapiirille. Odottavan perheen kohtaaminen ja hoito koettiin äitisuuntautuneeksi ja arvokkaaksi mutta isät ohittavaksi.
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Evolution des cycles de vie : modélisation et évolution expérimentale sur la levure Saccharomyces cerevisiae / Evolution of life cycles : modelling and experimental evolution using the yeast Saccharomyces cerevisiaeRescan, Marie 27 September 2016 (has links)
La reproduction sexuée conduit à l'alternance d'une phase haploïde et d'une phase diploïde, dont la durée relative est très variable entre taxons. La proportion du cycle de vie passée en phase haploïde et en phase diploïde a d'importantes conséquences sur de nombreux processus adaptatifs. Cette thèse combine des approches théoriques qui explorent l'effet de facteurs génétiques et écologiques sur l'évolution des cycles de vie, et un travail expérimental sur l'effet de la ploidy sur l'évolution de l'isolement reproducteur entre populations. La partie théorique a consisté à intégrer des composantes écologiques dans des modèles génétiques pour l'évolution des cycles de vie. En particulier, j'ai exploré l'interaction entre la différenciation de niche entre haploïdes et diploïdes (qui favorise le maintien de cycles biphasiques, impliquant le développement des deux phases) et l'effet d'allèles délétères (qui favorisent soit l'haploïdie, soit la diploïdie). Tandis que la différentiation de niche (ou plus simplement, une différence de valeur sélective intrinsèque entre phases) stabilise les cycles intermédiaires, la présence d'allèles délétères conduit souvent à un branchement évolutif, avec la coexistence stable d'allèles codant pour l'haploïdie et la diploïdie. Cependant, des fluctuations temporelles de l'habitat permettent d'empêcher ce branchement et de stabiliser les cycles biphasiques. La partie expérimentale a consisté à comparer la dynamique de l'isolement reproducteur entre petites populations de levure haploïdes et de diploïdes avec de taux de mutations élevés. Les résultats montrent que tandis que les hybrides haploïdes ont une valeur sélective plus faible que leurs parents, les hybrides diploïdes bénéficient du phénomène d'hétérosis en génération F1, et ont encore une valeur sélective plus élevée que leurs parents en génération F2. La variance de la valeur sélective des hybrides était cependant beaucoup plus élevée chez les haploïdes, avec la production de certains génotypes très performants. / Sexual reproduction leads to an alternation between haploid and diploid phases, whose relative length varies widely across taxa. The proportion of the life cycle spent in the haploid and diploid phase has important consequences on a number of adaptive processes. This thesis combines theoretical approaches exploring the effect of genetic and ecological factors on the evolution of life cycles, and experimental work on the effects of ploidy on the evolution of reproductive isolation between populations. The theoretical part consisted in integrating ecological components into genetic models for the evolution of life cycles. In particular, I explored the interplay between niche differentiation between haploids and diploids (known to favour the maintenance of biphasic life cycles, involving development in both phases) and the effect of deleterious alleles (known to favour either haploid or diploid life cycles). While niche differentiation (or more simply intrinsic fitness differences between phases) stabilizes biphasic cycles, the presence of deleterious alleles often lead to evolutionary branching and to the stable coexistence of alleles coding for haploid and diploid cycles. Branching is prevented, however, when temporal environmental fluctuations are included into the model. The experimental part consisted in comparing the dynamics of reproductive isolation between small populations of haploid and diploid yeasts with elevated mutation rate. The results show that while haploid hybrids tend to have a lower fitness than their parents, diploid hybrids benefit from heterosis in the F1 generation, and still have a higher fitness than the diploid homozygous parents in the F2 generation. However, the variance of hybrid fitness was much higher in haploids, with the production of some highly fit genotypes.
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Effects of an Insecticide on Competition in Anurans: Could Pesticide-Induced Competitive Exclusion be a Mechanism for Amphibian Declines?Distel, Christopher A. 02 August 2010 (has links)
No description available.
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The impacts of habitat characteristics on the conservation of a forest-associated amphibianWetsch, Olivia 26 July 2022 (has links)
No description available.
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Gene expression profiling of two fish helminths throughout their complex life cycles. Are parasite’s life stages genetically decoupled?Gramolini, Laura 15 July 2024 (has links)
Komplexe Lebenszyklen sind eine häufige, aber anspruchsvolle Lebensweise von Parasiten. Parasiten mit komplexen Lebenszyklen infizieren nacheinander mehrere Wirte und passen sich an verschiedene ökologische Nischen an. Werden in diesem Szenario dieselben Gene in allen Wirten einheitlich exprimiert? Die Hypothese der adaptiven Entkopplung besagt, dass verschiedene Stadien in einem komplexen Lebenszyklus genetisch und evolutionär unabhängig sind, was bedeutet, dass die Selektion auf Parasitenmerkmale in einem Wirt keine Auswirkungen auf Merkmale in anderen Wirten hat.
Wir haben diese Hypothese anhand von zwei Parasitenarten getestet: dem Bandwurm Schistocephalus solidus und dem Fadenwurm Camallanus lacustris. Die Transkriptomsequenzierung wurde an Proben während ihrer komplexen Lebenszyklen durchgeführt. Die Genexpressionsanalyse wurde durchgeführt, um Gene zu identifizieren, die zwischen den Wirten, zwischen den Funktionsstadien und zwischen den Bedingungen unterschiedlich exprimiert werden. Darüber hinaus wurde mit einer Analyse der Anreicherung von Gensätzen untersucht, ob ähnliche biologische Funktionen von ähnlichen Genen in verschiedenen Stadien kodiert werden.
Unsere Ergebnisse zeigen signifikante Unterschiede in der Genexpression zwischen den verschiedenen Stadien, wobei keine positive Korrelation zwischen Stadien mit derselben Aufgabe oder demselben Wirt beobachtet wurde. Gene, die in einem Stadium hochreguliert (oder herunterreguliert) werden, werden in anderen Stadien nicht in ähnlicher Weise exprimiert. Dies spricht für die Unabhängigkeit der einzelnen Stadien bei der Genexpression, die es den Parasiten ermöglicht, ihren Phänotyp als Reaktion auf unterschiedlichen Selektionsdruck zu modulieren. Diese Ergebnisse bestätigen die Hypothese der adaptiven Entkopplung bei parasitären Würmern und bieten Einblicke in den evolutionären Erfolg dieser Lebensweise. / Complex life cycles are a common but demanding lifestyle among parasites. Parasites with complex life cycles sequentially infect multiple hosts, adapting to various ecological niches using information encoded within a single genome. In this scenario, are the same genes expressed consistently across all hosts, as might occur when parasite stages perform similar functions? The adaptive decoupling hypothesis posits that different stages in a complex life cycle are genetically and evolutionarily independent, meaning selection on parasite traits in one host does not affect traits in other hosts.
We tested this hypothesis using two species of parasites: the tapeworm Schistocephalus solidus and the nematode Camallanus lacustris, both of which have three-host life cycles. Transcriptome sequencing was performed on samples throughout their complex life cycles, generating transcriptomes from 10 stages of S. solidus and 7 stages of C. lacustris. Gene expression analysis was conducted to identify genes differentially expressed between hosts, between functional stages, and between conditions. Additionally, gene set enrichment analysis assessed whether similar biological functions are encoded by similar genes across stages.
Our findings demonstrate significant differences in gene expression across stages, with no positive correlation observed between stages sharing the same task or host. The highest correlation occurred between stages sampled close in time.
In conclusion, the lack of positive correlation between different life cycle stages indicates that genes up-regulated (or down-regulated) in one stage are not similarly expressed in other stages. This evidence supports the independence of each stage in gene expression, enabling parasites to modulate their phenotype in response to different selective pressures. These findings corroborate the adaptive decoupling hypothesis in parasitic worms with complex life cycles, offering insights into the evolutionary success of this lifestyle.
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The role of congregational management in creating and maintaining a healthy churchMellody, Michael 16 September 2011 (has links)
This study considers the ways in which congregational management contributes to
maintaining the healthy church through the supporting role of supplying, monitoring
and controlling the human, physical, financial, and informational resources needed to
allow the pastors to lead the congregation-centred church to fulfil its mission. It was
found that congregational managers help to prevent their churches declining into illhealth
by helping the pastorate to retain current congregants and attract new ones
through charisma. This requires them to first study, analyze and classify the major parts
of the diverse congregation and surrounding community and then monitor them to
foresee and forestall problems. They play multiple roles in efficient administration, asset
management, targeted church adverting, human relations, risk management, project
management, professional standards auditing and maintenance, community relations
with all faiths, charity, mission, and, above all, customer relations. Recommendations
are made for enhancing congregational management’s role in the healthy church. / Practical Theology / M.Th. (Practical Theology)
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Monogeneans of the Southern Fiddler Ray, Trygonorrhina Fasciata (Rhinobatidae) in South Australia: an exceptional model to compare parasite life history traits, invasion strategies and host specificity.Glennon, Vanessa January 2008 (has links)
Trygonorrhina fasciata (Rhinobatidae) specimens naturally infected by three monogenean species were captured and maintained in marine aquaria to promote a continuous parasite load. Monogenean eggs recovered from aquaria provided larvae for descriptions and life history experiments. I describe the adult, larva and post-larval development of a new species of hexabothriid, Branchotenthes octohamatus, from the gills. This is the first monogenean larva described with only eight hooklets. This character may be useful to help resolve problematic relationships within the Hexabothriidae and offers insight into more general hypotheses about relationships within the Monogenea. I also redescribe the adult of Calicotyle australis (Monocotylidae) from the cloaca and describe the larva. The number and arrangement of larval ciliated epidermal cells and sensilla was revealed using silver nitrate. I redescribe Pseudoleptobothrium aptychotremae (Microbothriidae) adults from the skin of T. fasciata, representing a new host and locality record. Larval anatomy and post-larval development are also documented. The presence of six needle-like spicules in the larval haptor is confirmed, supporting an earlier theory that spicules are ancestral vestiges. My studies revealed three different egg hatching, host finding strategies and larval ‘types’. Branchotenthes octohamatus has a ‘sit-and-wait’ strategy, entirely dependent on mechanical disturbance to stimulate eggs to hatch. Larvae are unciliated, cannot swim, lack pigmented eyespots and show no photo-response but may survive for more than two days after hatching at 22ºC. In contrast, eggs of C. australis hatch spontaneously with a strong diurnal rhythm in the first few hours of daylight when exposed to a LD12:12 illumination regime. Larvae are ciliated and can swim, have pigmented eyespots, are photo-positive and can remain active and survive for up to 24 h after hatching at 22ºC. Eggs of P. aptychotremae may have a ‘bet-hedging’ strategy. Some eggs hatch spontaneously and rhythmically in an LD12:12 regime during the last few hours of daylight but their low hatching success rate suggests that other eggs may require a different cue provided by the host. Larvae are ciliated, can swim, lack pigmented eyespots, show no photo-response and remain active for only a few hours at 22ºC. Experiments using the fluorescent dye, 5(6)-carboxyfluorescein diacetate N-succinimidyl ester (CFSE) revealed B. octohamatus on gills of T. fasciata within 30 min of exposure to the host. This provides strong evidence that larvae invade the gills directly via the host’s inhalant respiratory current and do not migrate after initial attachment elsewhere. Five rhinobatid species (Aptychotrema vincentiana, T. fasciata, Trygonorrhina sp. A, A. rostrata and Rhinobatos typus), with overlapping distributions spanning west, south and east Australian coastal waters were surveyed for monogeneans at four locations between Fremantle, Western Australia and Stradbroke Island, Queensland. Genetic homogeneity, using the mitochrondrial gene Cytochrome b (cytb) and the nuclear marker, Elongation factor-1 alpha (EF1a), was observed for all Branchotenthes and Calicotyle specimens irrespective of collection locality or rhinobatid species. Genetic homogeneity was observed for Pseudoleptobothrium specimens collected in western and southern Australia. However, local genetic heterogeneity was apparent among Pseudoleptobothrium specimens collected from two sympatric host species in New South Wales. Analyses revealed a highly divergent clade, indicating a morphologically cryptic, ancestral species. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1323070 / Thesis (Ph.D.) -- University of Adelaide, School of Earth and Environmental Sciences, 2008
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