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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.
131

Stratégies diagnostiques et qualité de vie en oncologie bronchopulmonaire - Programme d'évaluation de la TEP dans l'inter-région Grand-Est / Diagnostic strategies and quality of life in pulmonary oncology an evaluation program of PET implantation in the Northeastern Regions of France

Lemonnier, Irawati 17 January 2011 (has links)
Introduction : L'installation de caméras de Tomographie à Emission de Positons (TEP) a eu lieu en 2003 dans l'inter région Grand-Est de la France. Plusieurs études ont montré ses performances diagnostiques et ses bénéfices en évitant: des interventions de chirurgie exploratrice devenue inutile (thoracotomie aux séquelles douloureuses, laparotomie exploratrice), et certains examens complémentaires d'imagerie ou d'exploration fonctionnelle inutile. Objectifs : 1) évaluer le changement des stratégies diagnostiques du Nodule Pulmonaire Isolé (NPI) et du Cancer du Poumon Non à Petites Cellules (CPNPC) induit par l'implantation de la TEP dans l'inter - région Grand - Est de la France ; 2) mesurer l'impact du changement sur la qualité de vie des patients atteints d'un NPI et d'un CPNPC ; et 3) étudier le rôle pronostique de la QV sur la survie des patients atteint d'un CPNPC.Méthodes : Etude prospective multicentrique constituant 2 cohortes « Avant (2001 - 2002) » et « Après (2004 - 2005) » de l'implantation de la TEP. Ont été recueillis : les caractéristiques sociodémographiques des patients, clinique du NPI et du CPNPC, les examens diagnostiques et traitements réalisés jusqu'à 6 mois après la fin du bilan. Deux auto-questionnaires de QV (SF36 et QLQ C-30) ont été distribués à 3 et 6 mois après la fin du bilan diagnostique.Résultats : 1) Nous avons observé une diminution du nombre d'examens réalisés au cours du bilan diagnostique d'un NPI de 4 examens en phase avant à 3 en moyenne en phase après. Néanmoins, la fréquence des examens invasifs jugés évitables a posteriori pratiqués chez les patients ayant un NPI bénin n'était pas différente (47% phase avant versus 49% phase après). Un an après son installation, la TEP a été utilisée chez 11% des patients. 2) Les patients atteints d'un NPI et quelque soit sa nature, maligne ou bénigne, ont eu un score moyen de QV plus bas (-8 à -32 points, p<0.001) que celui mesuré dans la population générale française indépendamment du sexe et de l'âge. Les scores QV des patients ayant un NPI bénin se révélaient être statistiquement plus élevés que ceux des patients ayant un NPI malin, notamment dans les dimensions « fonctionnement social », « rôle physique » et « rôle émotionnel » (+10, +14 et +18 points respectivement, p=0,02 à 0,04).3) Les bons scores en fonctionnement physique en SF-36 (HR=0.78 ; IC=0.68 - 0.90 ; p<0.001), et en la limitation due à l?état physique en QLQ-C30 (HR=0.53 ; IC=0.59 - 0.89 ; p=0.003) indiquant une bonne perception des patients sur leurs fonctionnement physique sont liés à une meilleure survie. Les symptômes élevés de constipation (HR=1.18 ; IC=1.005-1.38 ; p=0.04) en QLQ-C30, par contre, est lié à une mauvaise survie. Le sexe féminin est lié à une meilleure survie (HR=0.55 ; IC=0,33 - 0,94 ; p=0,04). Cependant, le stade III et IV du CPNPC est associé à une mauvaise probabilité de survie (HR=1,72 ; IC=1,16 - 2,57 ; p=0,007).Discussion/conclusion : Les stratégies diagnostiques du NPI ont changé. L'impact de cette maladie, mesuré de façon subjective par la qualité de vie (QV) des patients peut indiquer certains domaines essentiels à améliorer dans sa prise en charge car une meilleure QV en oncologie broncho-pulmonaire est associée à une meilleure survie / Background: The Positron Emission Tomography was installed in 2003 in the North-eastern region of France. Previous studies showed its diagnostic performance and its benefices in avoiding: surgical exploratory interventions proved to be unnecessary a posteriori (for example, thoracotomy or laparotomy with painful consequences), and certain complementary imaging tests or unnecessary functional explorations. Objectives : 1) to evaluate changes in diagnostic strategies of Solitary Pulmonary Nodule (SPN) and Non Small Cell Lung Cancer (NSCLC) induced by the implantation of PET in the Northeastern region of France ; 2) to mesure the impact of these changes on the health related quality of life (HRQoL) of patients with SPN and NSCLC; and 3) to study the prognostic role of the HRQoL on the survival of patients with NSCLC.Methodes: An observational, prospective, multi-center design was applied. Two cohorts « Before (2001 - 2002) - After (2004 - 2005) » the PET implantation in the regions were settled up. Data collected included: patients' socio-demographic and clinical characteristics, the diagnostic tests and then treatments that were carried out during 6 months after the end of the diagnostic process. Two HRQoL questionnaires (the generic questionnaire SF-36 and the cancer specific one QLQ-C30) were distributed at 3 and 6 months after the end of the diagnostic process.Results:1) The number of diagnostic tests of patients with SPN decreased significantly from a mean of 4 in the before-PET to 3 tests in the after-PET period. Meanwhile, there was not any difference of the frequency of invasive tests considered unnecessary aposteriori for patients with benign SPN (47% before-PET versus 49% after-PET period). One year after its installation, the PET was used in 11 % of diagnostic strategies. In 7.7% of cases it was used after the bronchoscopy. 2) A comparison of the QoL with that of the French general population revealed that patients with SPN, whatever the diagnosis, benign or malignant, had worse mean scores (-8 to -32 points, p<0.001) compared to the general population with similar age and sex. A difference of 24, 30 and 32 points were observed in the "physical functioning", "emotional role" and "physical role" (p<0.001). The scores of patients with benign nodule were higher than those of malignant, especially on "social functioning", "physical role", and "emotional role" (+10, +14 and +18 points respectively, p=0.02 to 0.04). 3) Good scores on "physical functioning" of SF-36 (HR=0.78; CI=0.68 - 0.90; p<0.001) as well as "role functioning" of QLQ-C30 (HR=0.53; CI=0.59 - 0.89; p=0.003) were related to a better survival. Higher symptoms of constipation (HR=1.18; CI=1.005-1.38; p=0.04) in QLQ-C30 were associated to a worse one. While being a woman was associated to a better survival (HR=0.55 ; CI=0,33 - 0,94 ; p=0,04), the stage III and IV of the NSCLC was related to a lower one (HR=1,72 ; CI=1,16 ? 2,57 ; p=0,007) .Conclusion: The diagnostic strategies of SPN changed after PET was available for medical practice. This study showed the negative impact of SPN to patients' HRQoL. It indicates the domains in which health practitioners could interfere in order to improve the management of these diseases, because this study confirmed previous studies in pulmonary oncology, that patients' QoL is related to the survival
132

A influ?ncia da paisagem na forma e no tamanho da asa de tr?s esp?cies de Euglossini (Hymenoptera; Apidae)

Ribeiro, Maril?a Gon?alves 17 March 2017 (has links)
Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2018-07-11T21:45:03Z No. of bitstreams: 1 disserta??o-defesa-1.pdf: 1721541 bytes, checksum: 58ddaafa9ef0b17a788f4c20418c261e (MD5) / Made available in DSpace on 2018-07-11T21:45:03Z (GMT). No. of bitstreams: 1 disserta??o-defesa-1.pdf: 1721541 bytes, checksum: 58ddaafa9ef0b17a788f4c20418c261e (MD5) Previous issue date: 2017-03-17 / Funda??o de Amparo ? Pesquisa do Estado da Bahia - FAPEB / This work has aimed to evaluate the size and shape of the wing of individuals of three Euglossini bee species (Euglossa cordata (Linnaeus, 1758), Euglossa ignita Smith, 1874 and Eulaema atleticana Nem?sio, 2009). For that, geometric morphometrics methods, as well as landscape metrics, were used for such evaluation. The analyzed specimens were collected in five areas, being four forest areas and one area of Agroforestry System (SAF). Morphometric analyzis were started with the right wing photograph of the individuals of each species and with the determination of anatomical landmarks and semilandmarks. Subsequently, the Cartesian coordinates obtained were used for analysis of variance of the shape and size of the wing of the populations. The results of the shape analysis were significant for the three species (p<0.05) and demonstrated that the individuals collected within the SAF area have had the greatest divergences in the shape of the wing. On the other hand, size differences were significant only for the populations of E. ignita (ANOVA: F = 5.923 and p = 0.00045). For E. cordata and El. Atleticana, there has been a significant correlation between morphometric data and landscape metrics (r<0.05), which shows a close relationship between these species and the forest cover. Thus, the present work underlines the importance of Euglossini bees in environmental quality monitoring studies, since morphometrics differences may reveal the existence of environmental stress. / Este trabalho teve como objetivo avaliar o tamanho e a forma da asa de indiv?duos de tr?s esp?cies de abelha Euglossini (Euglossa cordata (Linnaeus, 1758), Euglossa ignita Smith, 1874 e Eulaema atleticana Nem?sio, 2009) em resposta ? estrutura da paisagem. Assim, as abelhas foram coletadas em quatro fragmentos florestais com marcante influ?ncia antr?pica e numa ?rea de sistema agroflorestal(SAF). Para tal avalia??o, utilizou-se m?todos de morfometria geom?trica, bem como m?tricas da paisagem. As an?lises morfom?tricas iniciaram com a fotografia da asa direita dos indiv?duos de cada esp?cie e com a determina??o de marcos e semimarcos anat?micos. Posteriormente, as coordenadas cartesianas obtidas foram utilizadas para an?lise de vari?ncia da forma e do tamanho da asa das popula??es. Os resultados da an?lise de forma foram significativos (p<0.05) para as tr?s esp?cies e demonstraram que os indiv?duos coletados dentro da ?rea de SAF possuem as maiores diverg?ncias na forma da asa. Por sua vez, as diferen?as de tamanho foram significativas apenas para as popula??es de E. ignita (ANOVA: F= 4,557 e p= 0,001801. Para E. cordata e El. atleticana, houve correla??o significativa entre dados morfom?tricos e as m?tricas da paisagem (r<0.05), o que demonstra uma estreita rela??o destas esp?cies com a cobertura florestal. Assim, o presente trabalho salienta a import?ncia das abelhas Euglossini nos estudos de monitoramento de qualidade ambiental, uma vez que diferen?as morfom?tricas podem revelar a exist?ncia de stress ambiental.
133

Abelhas e vespas solitárias (Hymenoptera, Aculeata) ocupando ninhos-armadilha e recursos alimentares utilizados por Centris (Heterocentris) analis e Centris (Heterocentris) terminata (Hymenoptera, Centridini) em um fragmento de Mata A / Solitary bees and wasps (Hymenoptera, Aculeata) occupying trap-nests and food resources utilized by Centris (Heterocentris) analis and Centris (Heterocentris) terminata (Hymenoptera, Centridini) in an Atlantic forest fragment in the urban zone of Salvador, Bahia, Brazil.

Cruz, Reinanda Lima da 27 April 2016 (has links)
O objetivo do presente estudo foi inventariar a diversidade de espécies de abelhas e vespas solitárias que nidificam em cavidades preexistentes em um fragmento de Mata Atlântica, componente da paisagem urbana de Salvador, Bahia, ocupado pelo Parque Zoobotânico Getúlio Vargas (PZBGV) e pelo campus da Universidade Federal da Bahia (UFBA), Ondina. Além disso, foi feita a identificação dos recursos florais utilizados por duas espécies de abelhas, Centris (Heterocentris) analis e Centris (Heterocentris) terminata, para aprovisionamento das suas células de cria. A amostragem foi realizada durante o período de maio de 2014 a outubro de 2015, e os ninhos-armadilha utilizados consistiam de tubos de cartolina preta, blocos de madeira e gomos de bambu. Foram instalados no campo 1.192 ninhos-armadilha, distribuídos em oito suportes, sendo quatro colocados na área do Parque Zoobotânico e quatro colocados na área ocupada pelo campus da UFBA. As inspeções aos ninhos foram feitas mensalmente e os ninhos concluídos foram coletados e substituídos por novos ninhos-armadilha vazios. Os ninhos ocupados foram levados para o laboratório. No laboratório, os ninhos foram mantidos à temperatura ambiente e observados diariamente até a emergência dos adultos. Foram amostrados 409 ninhos pertencentes a sete espécies de vespas e cinco de abelhas, sendo 189 coletados no campus da UFBA e 220 no PZBGV. Do total de ninhos obtidos, 234 ninhos foram colonizados por cinco espécies de abelhas pertencentes a família Apidae: Centris analis, Centris terminata, Xylocopa frontalis, Euglossa sp. e Tetrapedia diversipes. As abelhas nidificaram com maior frequência no PZBGV (127 ninhos) do que no campus da UFBA (107 ninhos). Em relação às vespas, do total de 175 ninhos, 82 foram coletados na UFBA e 93 no PZBGV, tendo emergido indivíduos de sete espécies pertencentes a três famílias: Podium denticulatum e Podium sp. (Sphecidae); Auplopus pratens e Auplopus subaurarius (Pompilidae); Trypoxylon sp.1, Trypoxylon sp.2 e Trypoxylon lactitarse (Crabronidae). Entre as espécies de abelhas, C. analis foi a mais abundante, seguida por C. terminata. As espécies de vespas mais abundantes foram Trypoxylon sp.2 e P. denticulatum. As maiores frequências de atividade de nidificação das espécies de abelhas e vespas ocorreram nos meses com temperaturas elevadas e baixos índices pluviométricos (janeiro-março). Das espécies vii analisadas, apenas C. analis, P. denticulatum e Trypoxylon sp. 2 apresentaram diferenças significativas na razão sexual, as quais foram enviesadas para machos. A taxa de mortalidade para as espécies de abelhas e vespas foi maior na UFBA (55,08%) do que no PZBGV (44,92%). A mortalidade foi ocasionada, na grande maioria dos casos, por causas desconhecidas. Para identificação das fontes dos recursos florais utilizados por C. analis e C. terminata foi realizada a análise polínica a partir de 53 ninhos de C. analis e 20 ninhos de C. terminata fundados durante o período de maio de 2014 a abril de 2015. A análise do conteúdo polínico residual dos ninhos foi realizada pelo método de acetólise convencional. Foram identificados 12 tipos polínicos, pertencentes a sete famílias vegetais: Malpighiaceae, Bignoniaceae, Solanaceae, Fabaceae, Arecaceae, Polygalaceae e Sapindaceae. Destas famílias, Malpighiaceae foi a que teve os tipos polínicos mais frequentes nos ninhos de ambas as espécies de abelhas. Nos ninhos de C. analis foram encontrados 12 tipos polínicos e nos ninhos de C. terminata 8 tipos polínicos. Os tipos polínicos com as maiores frequências de utilização por C. analis e C. terminata foram: Malpighia emarginata, Byrsonima sericea, Stigmaphyllon cavernulosum e Aeschynomene paucifolia.Os resultados encontrados são de extrema relevância para o conhecimento das plantas fornecedoras de recursos florais utilizados para aprovisionamento larval, consumo e construção dos ninhos, elaboração de plano de manejo, conservação das abelhas do gênero Centris e das plantas visitadas pelas mesmas. Os resultados sugerem que a área estudada funciona como refúgio para espécies de abelhas e vespas solitárias. / The aim of this study was to inventory the diversity of species of solitary bees and wasps that nest in artificial cavities in an Atlantic Forest fragment in the urban landscape of Salvador, Bahia. This area is occupied by the campus of the Universidade Federal da Bahia (UFBA) and by the Parque Zoobotânico Getúlio Vargas (PZBGV). We also identified the food resources collected by Centris analis and Centris terminata females. The samples were collected from May 2014 to October 2015 using artificial cavities made of black cardboard, wooden blocks, and bamboo canes (trap-nests methodology). We installed 1.192 trap-nests in the field, distributed in eight stands, four for each area. Inspections were made monthly and occupied nests were removed and brought to the laboratory. The empty cavities were filled with new nests. In the laboratory, the nests were kept at room temperature and observed daily until adult emergence. We sampled seven wasp species and five bee species in the two areas of this study, in a total of 409 nests: 189 nests in UFBA and 220 in PZBGV. Of these, 234 nests were made by five bee species from four genera of Apidae family: Centris analis, Centris terminata, Xylocopa frontalis, Euglossa sp. and Tetrapedia diversipes. Bees nest more frequently in PZBGV (127 nests) than on the campus of UFBA (107 nests). In relation to the wasps, we collected 175 nests, 82 were collected in UFBA and 93 in PZBGV, and emerged individuals from seven species of three families: Podium denticulatum and Podium sp. (Sphecidae); Auplopus pratens and Auplopus subaurarius (Pompilidae); Trypoxylon sp.1, Trypoxylon sp.2 and T. lactitarse (Crabronidae). Among the bee species, C. analis was the most abundant, followed by C. terminata. The most abundant wasp species were Trypoxylon sp.2, followed by P. denticulatum. The highest frequency of nesting activity of the species of bees and wasps occurred in the months with high temperatures and low rainfall (January to March). Only C. analis, P. denticulatum and Trypoxylon sp. 2 showed significant differences in the sex ratio, which were male-bias. The mortality rate was higher in the UFBA (55.08%) than in the PZBGV (44.92%) for both, bees and wasps. Unknown causes were the main causes of mortality. To identify the pollen resource used by C. analis and C. terminata, we analyzed 53 C. analis nests and 20 C. terminata nests, collected from May 2014 to April 2015. We found 12 pollen types belonging to seven families: ix Malpighiaceae, Bignoniaceae, Solanaceae, Fabaceae, Arecaceae, Polygalaceae and Sapindaceae, where Malpighiaceae was the most common for both species. We found 12 pollen types for C. analis and 8 for C. terminata, and the highest frequency pollen species were Malpighia emarginata, Byrsonima sericea, Stigmaphyllon cavernulosum, Aeschynomene paucifolia for both species analyzed. The results are extremely important for the knowledge of supplier plants of food resources used for larval supply, consumption and construction of nests, preparation of management plan, conservation of the genus Centris bees and plants visited by them.The studied forest fragment serve as refuge for species of bees and solitary wasps.
134

Visual ecology of nocturnal bees: how light intensity affects foraging activity in cambuci, a neotropical Myrtaceae / Ecologia Visual de Abelhas Noturnas: como a intensidade de luz afeta a atividade de forrageio no cambuci, uma Myrtaceae neotropical

Rodolfo Liporoni Dias 02 May 2018 (has links)
The foraging activity of day-active bees often rely on flower availability, light intensity and temperature. However, some bees developed a nocturnal habit and fly during the dusk, dawn and night. We still do not know how these bees cope with environmental factors, especially dimmer light levels, to explore flower earlier than their diurnal relatives. Given that typical bee apposition compound eyes work better in brighter environments and function in their limits in dim-light conditions, we can expect a larger dependence of light intensity for nocturnal groups. Nocturnal and crepuscular bees are frequent visitors of cambuci (Campomanesia phaea, Myrtaceae) in southeastern Brazil. We aimed to investigate how light intensity affects flower visitation of cambuci by nocturnal and crepuscular bees, also controlling for other environmental factors. We counted visits per minute along 30 nights/twilights in 33 cambuci trees from a commercial orchard, measuring the following environmental variables: light intensity, flower availability, temperature, air relative humidity and wind speed. Light intensity is the only variable that explained flower visitation of nocturnal bees in cambuci, which peaks at intermediate light levels that occur around 30 minutes before sunrise. The minimum light intensity threshold to bees start flying is of 0.00024 cd/m2, the first recorded value for nocturnal and crepuscular bees finding flowers in an agro-forest context. Our results highlight for the first time how nocturnal bees rely on light to explore resources and show that the bees light-dependent foraging activity is not always linear, as postulated by previous theoretic models. This is the first step to understand how nocturnal bees react to environmental factors. Our findings also bring concerns about possible negative effects of light pollution at night for cambuci-crepuscular bees interaction / O forrageio de abelhas geralmente depende de disponibilidade de flores, intensidade de luz e temperatura. Contudo, algumas abelhas desenvolveram hábitos noturnos e voam durante os crepúsculos e a noite. Não se sabe como essas abelhas lidam com os fatores ambientais, especialmente os reduzidos níveis de luminosidade. Dado que os olhos compostos de aposição de abelhas funcionam melhor em maiores luminosidades, espera-se uma maior dependência da luz para os grupos noturnos. Abelhas noturnas e crepusculares são visitantes frequentes do cambuci (Campomanesia phaea, Myrtaceae) no sudeste do Brasil. Nosso objetivo foi investigar como a intensidade de luz afeta a visitação floral do cambuci por abelhas noturnas e crepusculares, controlada também por outros fatores ambientais. Para isso, contamos as visitas a cada minuto ao longo de 30 noites/crepúsculos em 33 árvores de cambuci em um pomar comercial, medindo as seguintes variáveis ambientais: intensidade de luz, disponibilidade de flores, temperatura, umidade e velocidade do vento. A intensidade de luz foi a única variável que explicou a visitação floral de abelhas noturnas no cambuci, a qual tem um pico em níveis intermediários de luz que ocorrem ao redor de 30 minutos antes do nascer do sol. O limiar mínimo de intensidade de luz para as abelhas começarem a voar foi de 0.00024 cd/m2, o primeiro valor registrado para abelhas noturnas e crepusculares procurando por flores em um contexto agroflorestal. Nossos resultados destacam pela primeira vez como as abelhas noturnas dependem da luz para explorar recursos e mostram que essa dependência, para abelhas em geral, não é sempre linear, como postulado por modelos teóricos prévios. Este é o primeiro passo para entender como abelhas noturnas reagem a fatores ambientais. Nossos dados também trazem alertas para possíveis efeitos negativos da poluição luminosa à noite para a interação entre cambuci e abelhas noturnas
135

The detection of thermal windows in fossorial rodents with varied sociality degree

VEJMĚLKA, František January 2018 (has links)
Eight rodent species with fossorial activity differing in a number of characteristics such as ecology, climatic conditions, geographical distribution, or kinship were studied using infrared thermography in order to describe their surface temperature and its patterns. An attempt to describe the relation between surface temperature and varied social organisation in burrowing rodents was made.
136

Abordagem comparativa da maturação cuticular em abelhas sociais e solitárias utilizando-se RNA-seq, quantificação de hidrocarbonetos e microscopia eletrônica / A comparative approach of cuticular maturation in social and solitary bees using RNAseq, hydrocarbons\' quantification, and electron microscopy

Lopes, Tiago Falcón 01 November 2016 (has links)
Diferenças no timing da melanização e esclerotização do exoesqueleto são evidentes quando se compara a morfologia externa de abelhas de hábitos sociais e as solitárias. A esta diferença convencionamos chamar de heterocronia da maturação cuticular, o termo heterocronia significando variações no tempo relativo, ou ritmo, de um evento ontogenético em relação ao ancestral ou entre taxons. Propusemos que as abelhas sociais, que após a ecdise permanecem na colônia por vários dias, alcançariam a maturidade de alguns sistemas orgânicos, entre eles o tegumento, muito mais tarde que as espécies de abelhas solitárias que ao emergir partem imediatamente para atividades extra-nidais. Neste contexto, o objetivo deste trabalho consistiu em testar esta hipótese utilizando o tegumento em maturação das espécies de abelhas sociais, Apis mellifera e Frieseomelitta varia, e da espécie solitária Centris analis, em estudos comparativos de expressão gênica, ultraestrutura e quantificação de hidrocarbonetos cuticulares (CHCs). Para isto utilizamos sequenciamento de mRNA (RNA-seq), microscopia eletrônica de transmissão (MET) e cromatografia de gás e espectrometria de massas (CG/MS). Os perfis de expressão de genes da via de melanização/esclerotização cuticular (ebony e tan) diferenciaram as espécies sociais da solitária, assim como a expressão de genes com função na via de metabolismo de quitina (Cda5, Idgf4 e chitooligosacchariodolytic-domain-like) e de genes codificadores de proteínas estruturais da cutícula (CPR14, CPR17, CPR18, CPR25, CPR23, CPR26, Apd-3 e Apd-like). Genes com função na regulação da maturação cuticular (FTZ-F1, E74, Hr46 e Hr4) se mostraram co-expressos nas espécies sociais e os perfis de expressão destes genes, exceto Hr46, e de outros reguladores (Ethr, Hr38, Rickets e Ptx-1) também diferenciaram as espécies sociais da solitária. Ressaltamos em nossas análises os genes do ciclo circadiano, cuja expressão tem relação com a deposição de quitina cuticular, além de genes de vias de pigmentação não melanínicas. As análises de MET, abrangendo outras três espécies de abelhas (Bombus brasilienses: primitivamente eussocial; Euglossa cordata: facultativamente social; Tetrapedia diversipes: solitária), mostraram diferenças consistentes entre a ultraestrutura e espessura das cutículas das espécies sociais e solitárias, o que reforçou nossos resultados de RNA-seq. A quantificação absoluta dos CHCs diferenciou as abelhas sociais da solitária, consistente com a hipótese de heterocronia da maturação cuticular e com os perfis de expressão de genes envolvidos na biossíntese de CHCs. Assim, além de desvendar transcriptomas de tegumento de três espécies de abelhas, a comparação da expressão gênica aliada à análise de ultraestrutura da cutícula e quantificação de CHCs levaram à caracterização de diferenças no processo de maturação cuticular entre as espécies sociais e solitárias / Differences in the timing of exoskeleton melanization and sclerotization processes are evident when comparing the external morphology of social and solitary bee species. Such differences may constitute a relevant example of cuticular maturation heterochrony, this term referring to a genetic change in timing of an ontogenetic process relative to an ancestor or between taxons. We proposed that social bees, which remain protected inside the colony for many days before initiating outside nest activities, would reach the maturity of some organic systems, such as the integument (epidermis and cuticle), later than solitary bees, which start such activities immediately after ecdysis. We tested this hypothesis in a comparative study of the developing integument of eusocial bees, Apis mellifera and Frieseomelitta varia, and the solitary bee Centris analis. Using RNA-seq, we verified that the expression profiles of genes involved in cuticular melanization and sclerotization (ebony and tan), chitin deposition and organization (Cda5, Idgf4, chitooligosacchariodolytic-domain-like), and cuticle formation (CPR14, CPR17, CPR18, CPR25, CPR23, CPE26, Apd-3, Apd-like) were positively, correlated between the two eusocial species, but not between the eusocial and the solitary species. Some of the genes with roles in regulating exoskeleton maturation (FTZ-F1, E74, Hr46, Hr4) were co-expressed only in the eusocial species. The expression profiles of these genes (except Hr46) and other regulatory genes (Ethr, Hr38, Rickets, Ptx-1) were also positively correlated exclusively in the eusocial bees. We also highlighted the expression of genes involved in non-melanin pigment production and the expression of circadian rhythm genes that could be related to chitin layers deposition. Transmission electron microscopy analysis of the integument of the two eusocial and the solitary bee species, in addition to other three bee species (the primitively eusocial Bombus brasilienses; the facultatively social Euglossa cordata; the solitary bee Tetrapedia diversipes), showed differences in cuticle ultrastructure and thickness, thus supporting the RNA-seq data. In agreement with our hypothesis, CHC quantifications were consistent with the expression levels of genes involved in CHC biosynthesis, thus differentiating the superficial cuticle layer of the eusocial and solitary species. Together, the integument transcriptomes, ultrastructure, and CHC quantification allowed us to characterize differences in the timing of cuticle maturation in social and solitary bees
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Visual ecology of nocturnal bees: how light intensity affects foraging activity in cambuci, a neotropical Myrtaceae / Ecologia Visual de Abelhas Noturnas: como a intensidade de luz afeta a atividade de forrageio no cambuci, uma Myrtaceae neotropical

Dias, Rodolfo Liporoni 02 May 2018 (has links)
The foraging activity of day-active bees often rely on flower availability, light intensity and temperature. However, some bees developed a nocturnal habit and fly during the dusk, dawn and night. We still do not know how these bees cope with environmental factors, especially dimmer light levels, to explore flower earlier than their diurnal relatives. Given that typical bee apposition compound eyes work better in brighter environments and function in their limits in dim-light conditions, we can expect a larger dependence of light intensity for nocturnal groups. Nocturnal and crepuscular bees are frequent visitors of cambuci (Campomanesia phaea, Myrtaceae) in southeastern Brazil. We aimed to investigate how light intensity affects flower visitation of cambuci by nocturnal and crepuscular bees, also controlling for other environmental factors. We counted visits per minute along 30 nights/twilights in 33 cambuci trees from a commercial orchard, measuring the following environmental variables: light intensity, flower availability, temperature, air relative humidity and wind speed. Light intensity is the only variable that explained flower visitation of nocturnal bees in cambuci, which peaks at intermediate light levels that occur around 30 minutes before sunrise. The minimum light intensity threshold to bees start flying is of 0.00024 cd/m2, the first recorded value for nocturnal and crepuscular bees finding flowers in an agro-forest context. Our results highlight for the first time how nocturnal bees rely on light to explore resources and show that the bees light-dependent foraging activity is not always linear, as postulated by previous theoretic models. This is the first step to understand how nocturnal bees react to environmental factors. Our findings also bring concerns about possible negative effects of light pollution at night for cambuci-crepuscular bees interaction / O forrageio de abelhas geralmente depende de disponibilidade de flores, intensidade de luz e temperatura. Contudo, algumas abelhas desenvolveram hábitos noturnos e voam durante os crepúsculos e a noite. Não se sabe como essas abelhas lidam com os fatores ambientais, especialmente os reduzidos níveis de luminosidade. Dado que os olhos compostos de aposição de abelhas funcionam melhor em maiores luminosidades, espera-se uma maior dependência da luz para os grupos noturnos. Abelhas noturnas e crepusculares são visitantes frequentes do cambuci (Campomanesia phaea, Myrtaceae) no sudeste do Brasil. Nosso objetivo foi investigar como a intensidade de luz afeta a visitação floral do cambuci por abelhas noturnas e crepusculares, controlada também por outros fatores ambientais. Para isso, contamos as visitas a cada minuto ao longo de 30 noites/crepúsculos em 33 árvores de cambuci em um pomar comercial, medindo as seguintes variáveis ambientais: intensidade de luz, disponibilidade de flores, temperatura, umidade e velocidade do vento. A intensidade de luz foi a única variável que explicou a visitação floral de abelhas noturnas no cambuci, a qual tem um pico em níveis intermediários de luz que ocorrem ao redor de 30 minutos antes do nascer do sol. O limiar mínimo de intensidade de luz para as abelhas começarem a voar foi de 0.00024 cd/m2, o primeiro valor registrado para abelhas noturnas e crepusculares procurando por flores em um contexto agroflorestal. Nossos resultados destacam pela primeira vez como as abelhas noturnas dependem da luz para explorar recursos e mostram que essa dependência, para abelhas em geral, não é sempre linear, como postulado por modelos teóricos prévios. Este é o primeiro passo para entender como abelhas noturnas reagem a fatores ambientais. Nossos dados também trazem alertas para possíveis efeitos negativos da poluição luminosa à noite para a interação entre cambuci e abelhas noturnas
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Coupled Solitary Waves in Optical Waveguides

Mak, William Chi Keung, Electrical Engineering & Telecommunications, Faculty of Engineering, UNSW January 1998 (has links)
Soliton states in three coupled optical waveguide systems were studied: two linearly coupled waveguides with quadratic nonlinearity, two linearly coupled waveguides with cubic nonlinearity and Bragg gratings, and a quadratic nonlinear waveguide with resonant gratings, which enable three-wave interaction. The methods adopted to tackle the problems were both analytical and numerical. The analytical method mainly made use of the variational approximation. Since no exact analytical method is available to find solutions for the waveguide systems under study, the variational approach was proved to be very useful to find accurate approximations. Numerically, the shooting method and the relaxation method were used. The numerical results verified the results obtained analytically. New asymmetric soliton states were discovered for the coupled quadratically nonlinear waveguides, and for the coupled waveguides with both cubic nonlinearity and Bragg gratings. Stability of the soliton states was studied numerically, using the Beam Propagation Method. Asymmetric couplers with quadratic nonlinearity were also studied. The bifurcation diagrams for the asymmetric couplers were those unfolded from the corresponding diagrams of the symmetric couplers. Novel stable two-soliton bound states due to three-wave interaction were discovered for a quadratically nonlinear waveguide equipped with resonant gratings. Since the coupled optical waveguide systems are controlled by a larger number of parameters than in the corresponding single waveguide, the coupled systems can find a much broader field of applications. This study provides useful background information to support these applications.
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Evolutionary ecology of Malpighiaceae pollination at the species and community levels

Cappellari, Simone Caroline 18 November 2013 (has links)
Plant-pollinator interactions figure as key elements promoting the natural regeneration of terrestrial vegetation, as most plants depend on animals to transfer their gametes between flowers and produce seeds. Bees are the most common pollinators of plants and their interactions with flowers have served as model systems for the study of specialized mutualisms since Darwin's time. While most plants offer nectar as a reward and attract a variety of floral visitors, others produce distinctive types of resources which are sought by particular groups of pollinators. Such associations may involve specialization at the morphological, behavioral, or physiological levels and are especially common in tropical habitats. The interactions between oil-producing flowers of Neotropical Malpighiaceae and oil-collecting bees are an example of a specialized mutualism in which plants offer lipids to attract pollinators that use the resource to build nest cells and feed their offspring. Although several studies have focused on specialized pollination at the species level, their effects on the organization of tropical communities remain largely unexplored. This dissertation aims to help fill this gap through an analysis of the mechanisms of pollinator partitioning in multi-species assemblages of specialists as well as a study of the organization of communities in which they occur. The motivation for pursuing the study of specialized interactions using Neotropical species of Malpighiaceae as a model system is outlined in the first chapter. In Chapter 2, I present an evaluation of the structural properties of a plant-pollinator community from the Cerrado, a seasonal ecosystem that hosts a large diversity of oil flowers. The third chapter analyzes pollinator partitioning and reproductive strategies promoting the coexistence of closely related Malpighiaceae. A possible outcome for the selective pressures imposed by the coexistence of specialists is presented in Chapter 4 by a case study providing evidence for a shift from specialized to generalized pollination in a Neotropical Malpighiaceae species. The last chapter includes reports of active floral oil foraging by males of Tetrapedia and a description of an oil storage structure without precedence among bees and unique to males of this genus suggesting that floral oils may also play a role in bees mating systems. / text
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Schwallwellen infolge der Bewegung einer Begrenzungsfläche

Röhner, Michael 29 September 2011 (has links) (PDF)
Restlöcher ausgekohlter Braunkohlentagebaue werden aus landeskulturellen und ökonomischen Gründen wasserwirtschaftlich als Speicher, Hochwasserrückhaltebecken, Klärteiche, Wassergewinnungsanlagen sowie zur Naherholung genutzt. Diese Restlöcher werden zum großen Teil von aus geschüttetem Abraum bestehenden Böschungen umschlossen. Bei Wasserspiegelschwankungen neigen diese unbefestigten Böschungen zum Rutschen. Als Folge dieser Böschungsrutschungen bilden sich auf der Wasseroberfläche Wellen, die eine beachtliche Größe erreichen können. Diese Schwallwellen übertreffen in ihren Ausmaßen die Windwellen in den Tagebaurestlöchern um ein Vielfaches. Um diese Erscheinungen vorausberechnen zu können, wurden im Hubert-Engels-Laboratorium der Sektion Wasserwesen Untersuchungen durchgeführt. Die Entwicklung einer allgemeingültigen Berechnungsmethode für die Schwallwelle bei der Bewegung eines Teiles der das Wasserbecken begrenzenden Böschung verlangt die Einführung erfassbarer Parameter wie der Breite der rutschenden Böschung, den zeitlichen Verlauf der Wasserverdrängung sowie Tiefen- und Lageverhältnisse des Beckens. Die dafür notwendigen Kennzahlen können nur näherungsweise bestimmt werden, so dass einfache Beckengeometrien, ein über die Rutschzeit gleich bleibender Verlauf der Wasserverdrängung und Erhaltung der Böschungskante einem Berechnungsverfahren zugrunde gelegt werden müssen. Für die Berechnung des Füllschwalles auf das ruhende Wasser sind einige Verfahren bekannt geworden, die auf eine gemeinsame Gleichung für die Berechnung der Schwallhöhe zurückzuführen sind. Für die ebene Ausbreitung des Füllschwalles über Ruhewasser ergeben sieh zwei prinzipielle Abflussmöglichkeiten: Auflösung in Wellen oder brandender Schwallkopf. Diese beiden Möglichkeiten sowie der Übergangsbereich werden durch FROUDE-zahlen festgelegt. Der Wellenkopf von Füllschwallwellen wird durch eine Einzelwelle gebildet. Die Rutschung einer Böschung wurde durch die gleichzeitige Horizontal- und Vertikalbewegung einer Platte nachgebildet. Die Bewegung der Platte, die entstehenden Wellen und die Kräfte auf Auflaufböschung wurden durch einen Oszillografen aufgezeichnet. Die Auswertung der Versuche ergab eine Übereinstimmung zwischen Messergebnissen und den Berechnungen nach den Gesetzen des Füllschwalls. Die sekundlich verdrängte Wassermenge pro Breiteneinheit und die Ruhewassertiefe bestimmen die entstehenden Schwallwellen. Ein Einfluss der vertikalen Bewegungskomponente ist im untersuchten Bereich nicht nachweisbar. Die dynamischen Kräfte auf die Abschlussböschung können durch den Impuls der Einzelwelle dargestellt werden. Die räumliche Ausbreitung der Schwallwellen wurde in einem Modell untersucht. Dabei wurde festgestellt, dass die größten Wellenhöhen in der Richtung der Bewegung der Platte auftreten, während die Wellenhöhen in seitlichen Ausbreitungsrichtungen kleiner sind. Berechnungsansätze für die maximale Wellenhöhe der front wurden ermittelt. Als Ergebnis wurde ein Berechnungsverfahren entwickelt, welches ausgehend von den Parametern dar Rutschung, die Eigenschaften der Schwallwellen einschließlich der durch sie hervorgerufenen Belastungen auf der Auflaufböschung ermöglicht. Mit diesem Berechnungsverfahren ist es möglich, Böschungen wirtschaftlich zu gestalten und schädliche Rückwirkungen auf das Staubecken durch Schwallwellen zu vermeiden. Bisher notwendige Kosten für eine sehr flache Gestaltung der Böschung können entfallen. Gleichzeitig bleibt ein größerer nutzbarer Stauraum erhalten. Die Digitalisierung der vorliegenden Arbeit durch die Sächsische Landesbibliothek - Staats- und Universitätsbibliothek Dresden (SLUB) wurde durch die Gesellschaft der Förderer des Hubert-Engels-Institutes für Wasserbau und Technische Hydromechanik an der Technischen Universität Dresden e.V. unterstützt.

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