Дисертації: "Mutualiste"

1

Combes, Victor. "Management mutualiste : la fin d'un oxymore ?" Thesis, Paris, HESAM, 2022. http://www.theses.fr/2022HESAC005.

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Les organisations mutualistes font partie de l’Economie Sociale et Solidaire, qui porte l’ambition d’une alternative face au modèle capitaliste dominant, malgré des pratiques hétérogènes et une banalisation galopante. Le management mutualiste, encore peu conceptualisé, est l’objet d’une thèse CIFRE au sein d’un groupe mutualiste français. Dans le cadre d’un positionnement épistémologique interprétativiste, notre travail empirique, sous-tendu par trois méthodes de collecte de données, s’est focalisé sur le suivi et l’analyse des effets d’un dispositif fondé sur le codéveloppement et proposé aux managers de ce groupe mutualiste. Il révèle un isomorphisme managérial en décalage avec la dynamique de l’alter souhaitée et prônée par les organisations mutualistes. Ce travail fait émerger : un apport conceptuel autour de l’intelligence relationnelle, des recommandations autour d’un management mutualiste, et la proposition d’un nouveau dispositif au service d’une culture mutualiste repensée
Mutualist organizations are part of the Social and Solidarity Economy, which carries the ambition of an alternative to the dominant capitalist model, despite heterogeneous practices and galloping trivialization. Mutualist management, still little conceptualized, is the subject of a CIFRE thesis within a French mutualist group. Within the framework of an interpretative epistemological position, our empirical work, underpinned by three data collection methods, focused on the monitoring and analysis of the effects of a system based on co-development and proposed to managers from this mutualist group. It reveals a managerial isomorphism that is out of step with the dynamics of the alter desired and advocated by mutual organizations. This work brings out: a conceptual contribution around relational intelligence, recommendations around a mutualist management, and the proposal of a new device for a redesigned mutualist culture

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2

Lapoutte, Alexandrine. "Gouvernance et légitimité : le modèle mutualiste." Thesis, Brest, 2013. http://www.theses.fr/2013BRES0071/document.

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Ce travail porte sur la gouvernance mutualiste. A partir d’un cadre d’analyse fondé sur la légitimité, nous avons cherché à comprendre comment s’exprime la légitimité en contexte mutualiste aujourd’hui. La proposition faite est qu’il existe nécessairement un gap entre la légitimité construite par les dirigeants et la légitimité perçue par les parties prenantes. Les dirigeants déploient alors des stratégies de légitimation par une communication mutualiste. Le modèle mutualiste deviendrait un outil de gestion des parties prenantes. Dans une phase de recherche quantitative auprès des parties prenantes impliquées, nous identifions un socle commun partagé ainsi qu’un gap mutualiste, qui porte sur la perception que l’entreprise maîtrise son projet et contribue au territoire. Une typologie des parties prenantes est dressée autour d’un clivage horizontal. L’analyse qualitative de discours révèle des systèmes de références sensiblement différents selon les entreprises. Nous distinguons trois approches dans la gestion de la légitimité en contexte mutualiste : communicationnelle, politique et managériale
This work concerns the mutualist governance. From a frame of analysis based on legitimacy theory, we tried to understand how appears legitimacy in mutual organisation context today. The proposal is that it exists inevitably a gap between the legitimacy built by managers and the legitimacy perceived by the stakeholders. Managers display then strategies of legitimization by a communication based on mutualist references. The mutualist model would become a management tool. In a phase of quantitative research with the involved stakeholders, we identify a common base shared between stakeholders, as well as a mutualist gap, which concerns the perception that the company masters its projet and contributes to the territory. A typology of the stakeholders is drawn up around a horizontal split. The qualitative analysis of speech reveals different patterns, based on communication, politics and management

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3

Baumard, Nicolas. "Une théorie naturaliste et mutualiste de la morale." Paris, EHESS, 2008. http://www.theses.fr/2008EHES0033.

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Ce travail cherche à répondre à la question : pourquoi sommes-nous moraux ? Il s'appuie sur deux approches. La première, naturaliste, reprend la tradition du sens moral (Shaftesbury, Hutcheson, et Adam Smith) et cherche à expliquer la morale à l'aide des outils des sciences naturelles (en particulier la théorie de l'évolution et la psychologie cognitive). La seconde, mutualiste, correspond à la tradition du contrat social (Hobbes, Rousseau ou Rawls) et considère les rapports moraux comme des rapports mutuellement avantageux. Ce travail se démarque donc à la fois des théories non naturalistes (comme les théories culturalistes ou les théories du choix rationnel) et des théories naturalistes non mutualistes (comme les théories de la sélection de groupe ou les théories basées sur les sentiments). Il montre comment, dans un grand nombre de situations morales (justice, assistance mutuelle, dilemme moral, jeux économiques, faute sans victime, limites de la communauté morale), les jugements comme les comportements s'expliquent mieux dans un cadre naturaliste et mutualiste
Why are we moral? This work relies on two approaches. The naturalist approach comes from the tradition of moral sense (Shaftesbury, Hutcheson, Adam Smith) and aims at explaining morality with the help of tools coming from natural sciences (evolutionary theory, cognitive psychology). The mutualist approach comes from the social contract tradition (Hobbes, Rousseau and Rawls) et see moral relationships as mutually advantageous interactions. Thus, this work distances oneself from non naturalist theories of morality ( culturalist theories, rational choice theories) and fron non mutualist theories (group selection or altruistic theories, sentimentalist or continuiste theories). This works shows that numerous moral situations (justice, solidarity, moral dilemmas, economic games, crimes without victim) are better explained in a naturalist and mutualist framework

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4

Storelli, Gilles. "Caractérisation de l’interaction mutualiste liant Drosophila melanogaster à son symbionte Lactobacillus plantarum." Thesis, Lyon, École normale supérieure, 2015. http://www.theses.fr/2015ENSL1041.

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Le microbiote a un impact majeur sur la physiologie de son hôte, cependant notre compréhension des mécanismes régulant la relation hôte/microbiote reste limitée. Nous utilisons un hôte modèle simple, la Drosophile, afin de répondre à ces questions. Durant mon doctorat, je me suis attaché à une étape particulière du cycle de vie de la Drosophile, sa phase larvaire. Celle-ci constitue sa phase de croissance et est influencée par le contexte nutritionnel. Le microbiote influence également cette étape: l’association avec la bactérie Lactobacillus plantarum tempère les effets de la carence alimentaire en soutenant un taux de croissance élevé et une maturation rapide, en modulant chez l’hôte l’activité de l’hormone Ecdysone et de l’insuline. En retour, L.plantarum bénéficie de l’association, les larvesassurant sa persistance dans la niche (la niche étant le substrat nutritif, les larves et les bactéries associées). Pour caractériser les mécanismes mis en jeu dans ce mutualisme nous avons décrit les réponses transcriptomiques et métaboliques de la larve et avons également étudié les perturbations métaboliques de la niche. Nos résultats mettent en avant l’optimisation de l’extraction des acides aminés du substrat comme facteur clef du mutualisme. L.plantarum active l’expression des protéases intestinales de l’hôte via la voie IMD/NF-κB, et bénéficierait en retour d’une quantité d’acides aminés plus importante assurant sa persistance. Ainsi, nos travaux contribuent à l’effort de compréhension desmécanismes régulant l’interaction hôte/microbiote et pourraient conduire à de nombreuses applications thérapeutiques, notamment dans le cadre de déséquilibres nutritionnels
Symbiotic bacterial populations (also called the “microbiota”) have a dramatic impact on their host’s physiology. However, our understanding of the mechanisms shaping host/microbes mutualism remains limited. We took advantage of Drosophila tractability to characterize the host’s and the microbial factors engaged in mutualism. During my PhD, I focused on the impact of the microbiota during the Drosophila larval phase, which constitutes its juvenile growth period. Drosophila larval phase is influenced by nutrition, but also by symbiotic microbes: specific association with the bacterium Lactobacillus plantarum buffers the deleterious effects of nutrient scarcity on the host’s juvenile growth, by sustaining greater growth rates and hastening maturation. L.plantarum mediate these effects by modulating the activity of the steroid hormone Ecdysone and the Insulin/Insulin-like Signaling pathway in its host. In return, L.plantarum benefits from Drosophila presence, as larvae ensure its long-term persistence in the niche (the niche being the nutritive substrate, the larvae and the bacteria dwelling on it). To characterize the mechanisms engaged in this mutualistic relationship, we described the host’s transcriptomic and metabolic responses to L.plantarum presence and characterized the metabolic perturbations occurring in the niche. Our results put forward the optimization of amino-acids extraction from the nutritive substrate as a cornerstone of mutualism. L.plantarum activates the expression of the host’s digestive proteases via IMD/NF-κB signaling and would benefit in return from an enhanced AA availability, which would help sustaining its long-term persistence. Altogether, our studies contribute to the understanding of the mechanisms regulating host/microbiota interaction and could lead to numerous therapeutic applications, notably aiming at counteracting the deleterious effects of nutritional imbalances

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5

Alburaki, Salam. "L'influence du statut mutualiste et coopératif sur la gouvernance d'entreprise : cas du secteur financier." Bordeaux 4, 2009. http://www.theses.fr/2009BOR40042.

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Les valeurs coopératives s'impriment dans la gouvernance des banques mutuelles. Le sociétaire est la pierre angulaire autour duquel tourne le système de gouvernance de ces banques affectées par la proximité, la responsabilité et la solidarité comme mode d'action et d'enracinement dans leur territoire et leur société locale. Le principe de base étant "un homme-une voix", la gouvernance coopérative est caractérisée par son aspect démocratique où le vote est le processus par lequel le sociétariat s'exprime. C'est une gouvernance souple et consensuelle. L'étude de deux cas de banques régionales en Aquitaine a démontré l'effet positif des valeurs coopératives dans la construction d'une relation de confiance mutuelle entre banque et client-sociétaire et l'effet positif de ces valeurs sur la performance, qui dépasse son aspect financier pour s'étendre à des aspects économique et social. Le modèle coopératif affiche, malgré les crises successives, une vitalité et une capacité d'adaptation qui assure sa pérennité
Values affect mutual Banks corporate governance. Member is the angular stone of governance system of these banks, for whose proximity, responsability and solidarity are guides for action and entrenchment in their territory and local society. Basic principal is "one voice-one vote", so mutual governance is characterised by its democratic aspect where voting is main process of claiming by membership. Mutual governance is soft and consensual. Case study of tow regional banks in Aquitaine reveals a positive effect of cooperative values on building trust relationship between mutual bank and client-member, and a positive effect of values on performance, beyond its financial aspect to cover economic and social aspects. Mutual banking presents, although successive crises, vitality and adaptation whose guaranted is continuity

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6

Lorenzi, Ange. "Analyse fonctionnelle d’une symbiose mutualiste : mécanismes de production du polydnavirus associé au parasitoïde ichneumonide Hyposoter didymator." Thesis, Montpellier, 2019. http://www.theses.fr/2019MONTG047.

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Les PDVs sont des virus à ADN associés à des dizaines de milliers d'espèces d'hyménoptères parasitoïdes. Ils sont divisés en deux taxa, les Bracovirus (BVs) et les Ichnovirus (IVs) associés respectivement aux sous-familles des Braconidae et Ichneumonidae. Les PDVs sont produits dans un tissu spécialisé du tractus génital (le calyx) de la femelle parasitoïde. Ils sont ensuite injectés lors de la ponte dans une chenille hôte, altérant les fonctions physiologiques et assurant un environnement favorable au développement de la progéniture du parasitoïde. Le génome des PDVs est intégré au génome des guêpes et est constitué de deux composants fonctionnels, avec d'une part des séquences impliquées dans la virulence chez l'hôte qui sont les seules à être encapsidées, et d'autre part des régions portant des clusters de gènes responsables de la production des particules virales. Ces gènes organisés en clusters arborent des caractéristiques de gènes viraux et sont exprimés spécifiquement dans le tissu réplicatif, le calyx. Ils dérivent de l’ancêtre viral des IVs actuels, mais ne présentent aucune homologie de séquence avec des gènes viraux connus ; en conséquence, la nature du virus ancêtre et la fonction des gènes qui en proviennent restent inconnues.Les régions portant ces groupes de gènes ont été nommées "Ichnovirus Structural Protein Encoding Regions (IVSPERs)". Cette thèse s'inscrit dans une démarche fondamentale visant à étudier la fonction des gènes IVSPERs afin de confirmer leur implication dans la production des particules virales d’IVs et de vérifier s’ils ont conservé ou non une fonction similaire à celle de leur ancêtre viral. Le modèle étudié a été celui de l'Ichnovirus associé à la guêpe parasitoïde Hyposoter didymator (HdIV).Pour répondre à la question de la fonction des gènes IVSPERs au cours de la production de HdIV, nous avons eu recours à la technologie de l'ARN interférence (ARNi) couplée à des approches de microscopie électronique. Nos travaux nous ont ainsi permis d’identifier des gènes IVSPERs impliqués dans différentes étapes clés du cycle de réplication des IVs. D’une part, nous avons mis en lumière au moins 6 protéines structurales intervenant dans l'assemblage et le trafic des particules virales dans les cellules du calyx. D’autre part, nous avons identifié un set de gènes IVSPERs qui jouent sur les niveaux de transcription des autres gènes viraux et qui pourraient vraisemblablement être impliqués dans la machinerie réplicative des IVs.L’ensemble des résultats obtenus ont permis de montrer l'efficacité de la technique de l'ARNi dans le but d'étudier la fonction des gènes viraux associés à ces guêpes parasitoïdes. D'autre part, les résultats présentés dans cette thèse constitue la première validation fonctionnelle de gènes impliqués dans la morphogénèse des IVs, mettant en évidence que ces protéines ont des fonctions similaires à celles de protéines virales "classiques", attestant de l'origine virale plus que probable des gènes contenus dans les clusters IVSPERs
PDVs are DNA viruses associated with tens of thousands of parasitoid hymenopteran species. They are divided into two taxa, the Bracoviruses (BVs) and the Ichnoviruses (IVs) associated respectively with the subfamilies of Braconidae and Ichneumonidae. PDVs are produced in a specialized tissue of the genital tract (calyx) of the female parasitoid. They are then injected during oviposition in a host caterpillar, altering its physiological functions and ensuring a favorable environment for the development of parasitoid offspring. The PDV genome is integrated into the genome of the wasps and consists of two functional components: firstly, sequences involved in virulence in the host that are the only ones to be packaged, and secondly regions with clusters of genes that are responsible for the production of viral particles. These clustered genes display viral gene characteristics and are specifically expressed in the replicative tissue, the calyx. They derive from the viral ancestor of current IVs, but show no sequence homology with known viral genes; as a result, the nature of the ancestral virus and the function of the genes that derivee from it remain unknown.Regions bearing these gene clusters have been named "Ichnovirus Structural Protein Encoding Re-gions (IVSPERs)". This thesis is part of a fundamental approach aimed at studying the function of IVSPERs genes in order to confirm their involvement in the production of IV particles and to verify whether they have retained or not a function similar to that of their viral ancestor. The model stud-ied was that of the Ichnovirus associated with the parasitoid wasp Hyposoter didymator (HdIV).To answer the question of IVSPERs gene function during HdIV production, we used RNA interference technology (RNAi) coupled with electron microscopy approaches. Our work has allowed us to identify IVSPER genes involved in different key steps of the IV replication cycle. On the one hand, we have highlighted at least 6 structural proteins involved in the assembly and trafficking of viral particles in calyx cells. On the other hand, we have identified a set of IVSPER genes that affect transcription levels of other viral genes and that could possibly be involved in the IVs replicative machinery.All the results obtained during this thesis made it possible to show the efficiency of the RNAi tech-nique to study the function of the viral genes associated with parasitoid wasps. On the other hand, the results presented here constitute the first functional validation of genes involved in the morphogenesis of IVs, highlighting that these proteins have functions similar to those of "classical" viral proteins, attesting to the more than likely viral origin of the genes contained in IVSPERs

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7

RABOTEAU, DOMINIQUE. "L'echelon local de la mutualite sociale agricole ou le mutualisme au quotidien." Angers, 1993. http://www.theses.fr/1993ANGE0008.

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La mutualite sociale agricole est un organisme prive charge de la gestion du service public que constitue l'application de la legislation sociale aux exploitants et aux salaries agricoles. Elle est sans doute l'un des organismes de protection les plus originaux tant par sa structure que par son activite; son histoire et son developpement est bati sur une philosophie le mutualisme, dont l'impact en milieu agricole a ete considerable. Le souci de concretion, les notions de solidarite et de participation a conduit la msa a adopter une organisation decentralisee dont l'echelon local est sans doute le plus important car c'est de lui qu'emane la plus large part du dynamisme et de la force de l'institution. L'histoire et les realisation de cet echelon local sont relates tout au long de ce document mais aussi les difficultes de maintenir un tel systeme et les possibilites de redynamisation
The "mutualite agricole" social affairs branch (m. S. A. Group), is a private organization, which ensures that legislation providing social protection is adequately applied to farm employees ans farmers. The "m. S. A. Group" can be considered unquestionably as the most original social welfare association as mush in the structures as in the activites. The growth and history of the "m. S. A. Group" are both based on a philosophy called mutualism which has a significant influence over the whole farming community. One of the major concern of the "m. S. S. Group" has been to put both abstract notions of solidarity and participation in concrete form. As a consequence, the group had been induced to adopt a tree fold decentralized structure. Out of these three operating stages, the volume of the local network operations appears to be the most significant since it makes a handsome contribution to the vitality and the strength of the institution. The history ans realizations of the local network are related along this document, but also the difficulties to maintain such a system and his future possibilities

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Durand, Lucile. "Étude de la diversité des peuplements épibiontes associés au tractus digestif de la crevette hydrothermale Rimicaris exoculata : une possible association mutualiste." Brest, 2010. http://www.theses.fr/2010BRES2004.

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Dans les écosystèmes hydrothermaux profonds, la chimiosynthèse microbienne est à la base des réseaux trophiques. Les symbioses entre des invertébrés et des micro-organismes sont fréquentes et peuvent être de différente nature et jouer différents rôles. La crevette Rimicaris exoculata est une espèce endémique des sites hydrothermaux de la Ride medio-Atlantique (MAR) et représente l’espèce majoritaire de la macrofaune de certains d’entre eux. Elle présente deux zones de colonisation microbienne, au niveau du céphalothorax et du tube digestif, mais leur rôle n’est pas encore établi. Ce travail a mis en évidence par approche moléculaire la présence de différentes communautés microbiennes dont une partie serait résidente, spécifique à R. Exoculata et représentée par des Deferribacteres, des Mollicutes et des Epsilonproteobacteria. Les approches microscopiques montrent la dominance d’épibiontes filamenteux étroitement associés à l’épithélium intestinal dont la croissance et l’installation semblent être contrôlées par l’hôte. Les approches moléculaires ont montré que: (1) les épibiontes du site hydrothermal Rainbow présentent une originalité taxinomique supposant une histoire évolutive ancienne tandis que les sites hydrothermaux Logatche et Ashadzé semblent avoir été colonisés plus récemment, (2) les épibiontes, non retrouvés dans le milieux extérieur et monophylétiques le long de la MAR pourraient être transmis verticalement et (3) il s’agirait d’une association mutualiste à caractère obligatoire. Ce travail de recherche a donc permis de poser les bases dans la compréhension du modèle symbiotique digestif R. Exoculata
In the deep-sea hydrothermal vents ecosystems, the driving energy comes from the microbial chemosynthesis. Symbioses between invertebrates and micro-organisms are common. They could be associations such as parasitism, commensalism or mutualism or even obligate symbioses and they could play distinct roles. The caridean shrimp Rimicaris exoculata is an endemic species of the Mid-Atlantic Ridge (MAR) hydrothermal sites. It is the main specie of the megafauna of some MAR sites. This crustacean harbors two microbial colonization regions, in the gill chamber and in the gut, but their roles are still unknown. Using various approaches, this work showed that there were distinct microbial communities among which a part would be resident and specific to R. Exoculata. This community is composed of Deferribacteres, Mollicutes and Epsilonproteobacteria. The microscopic approaches revealed the dominance of a single filamentous morphotype closely associated with the gut epithelium. Its settlement and growth seemed to be managed by the host. The molecular approaches showed that: (1) the Rainbow site epibionts harbored a phylogenetic particularity suggesting an ancient evolutionnary history whereas the Logatchev and Ashadzé seemed to have been colonized more recently by the association host-epibionts, (2) the epibionts, not retrieved in the surrounding environment and clustering i a monophyletic group along the MAR, could be vertically-transmitted, and (3) the association between R. Exoculata and the epibionts could be mutualistic and obligate. So, this research study gave the bases to understand the R. Exoculata symbiotic model

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Kawaye, Saadallah. "Les adénocarcinomes de l'ovaire : pronostic, moyens thérapeutiques : à propos de 104 cas suivis et traités à la Clinique mutualiste de la Digonnière, Saint-Étienne." Saint-Etienne, 1994. http://www.theses.fr/1994STET6210.

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Santos, Dina Maria Serrano. "Do mutualismo ao mercado. A banca mutualista em Portugal. Estudo de caso: o Crédito Agrícola Mútuo." Master's thesis, Faculdade de Ciêncais Sociais e Humanas, Universidade Nova de Lisboa, 2012. http://hdl.handle.net/10362/7355.

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Dissertação apresentada para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Sociologia, na especialidade de Sociologia Económica e das Organizações
Num mercado onde dominam os grandes grupos financeiros e onde existem estratégias agressivas de concorrência, o Crédito Agrícola, enquanto sistema cooperativo e mutualista bancário criado em 1911, tem conseguido não só sobreviver como obter sucesso. Este trabalho descreve o percurso do Crédito Agrícola desde a sua génese como projecto político, claramente alternativo à banca comercial, e a criação da legislação que o concebe de forma institucional até aos nossos dias, e procura compreender o seu crescimento e a sua readequação ao mercado e às instituições envolventes, também elas a sofrer uma enorme evolução. O capital social concretizado na sua origem, as alterações tecnológicas e organizacionais, a contenção e gestão do risco, a formação dos colaboradores e a standardização de procedimentos, são os principais factores analisados ao longo deste trabalho. As conclusões revelam a coalescência de círculos sociais diversos e de organizações de interesse na sua origem e em momentos chave de transformação institucional; um processo recente de isomorfismo institucional, a nível interno e externo, tendente a aproximar a instituição de crédito mutualista aos padrões de legitimidade vigentes no mercado financeiro; e evidenciam um trabalho simbólico de justificação discursiva visando resolver tensões valorativas causadas por esse isomorfismo, tornando os valores mercantis comensuráveis com os valores identitários da instituição mutualista.

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GIRAUD, FRANCK. "Une organisation charniere : la mutualite francaise." Paris, CNAM, 2000. http://www.theses.fr/2001CNAM0371.

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Toutes les questions posees a la mutualite francaise aujourd'hui ramenent toujours a une problematique de definition. Nous montrons que definir cette organisation mutualiste revient a decrire un processus d'organisation dans lequel sont liees les dimensions contextuelles, systemiques et individuelles. Nous tentons d'apporter un nouvel eclairage theorique sur la nature mixte et ambivalente d'une organisation mediatrice centrale, ni politique, ni economique, ni etatique, ni capitaliste, mais tout a la fois, liee a un contexte spatio-temporel et un positionnement particulier. A la charniere des organisations constituant le systeme de protection sociale, la mutualite emerge des conflits qu'elle articule entre des conceptions historiquement divergentes de l'organisation de la societe. Ses proprietes de mediation et de transition s'expliquent par une etonnante capacite de realignement. L'action d'une minorite active mutualiste joue un role essentiel dans cette dynamique du changement. En fonction de la grille de lecture elaboree, nous decryptons la situation actuelle de la mutualite, confrontee a de profonds changements contextuels, structurels et humains. Elle est toujours en mouvement, mais, atteinte dans ses valeurs, son modele et ses acteurs, elle a peut-etre perdu sa propriete de charniere. Le phenomene de deformation en cours de l'organisation risque cette fois de se muer en transformation. Les mutualistes ont identifies ce risque sous le terme de banalisation. La mutualite conserve toutefois un positionnement particulier. Elle demeure un enjeu dans un contexte ou la santes'identifie de plus en plus etroitement au social et devient un theme politique majeur du xxie siecle. Elle saura exploiter cet avantage strategique si elle reussit a integrer et conserver les hommes necessaires a sa reproduction, a instaurer au sein de son organisation une relation nouvelle entre espace de production et espace de representation, entre ses salaries et ses citoyens elus.

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Carrer, Moga Leslie-Anne. "Les ancres de Schein comme facteur explicatif du plafonnement de carrière volontaire des personnels vieillissants au sein des marches internes structurés - le cas d'une banque du réseau mutualiste -." Phd thesis, Université de la Méditerranée - Aix-Marseille II, 2010. http://tel.archives-ouvertes.fr/tel-00547529.

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De nombreuses études et écrits ont été réalisés sur le thème du plafonnement de carrière au cours de ces trente dernières années. Cependant, peu se sont penchés sur le degré de volonté qu'une personne peut avoir dans la construction d'un plafonnement de carrière, dès lors que celui-ci apparaît, non pas comme la conséquence de caractéristiques personnelles ou structurelles, mais comme un moyen d'atteindre un objectif précis. Existe-t-il des personnes qui peuvent accepter une situation de plafonnement de carrière ? Y a-t-il des raisons qui les amènent à rechercher une telle situation ? C'est au travers de l'analyse de personnes en situation de plafonnement au sein d'une banque française, que ces questions seront abordées. Les résultats de notre recherche font ressortir une idée maîtresse : l'impact de la présence d'une ou plusieurs ancres de Schein sur les attentes vis-à-vis de la carrière et la volonté d'être en situation de plafonnement. Ces résultats permettent ainsi de proposer un modèle du plafonnement volontaire.

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Moga, Leslie-Anne. "Les ancres de Schein comme facteur explicatif du plafonnement de carrière volontaire de personnels vieillissants au sein des marchés internes structurés : le cas d'une banque du réseau mutualiste." Thesis, Aix-Marseille 2, 2010. http://www.theses.fr/2010AIX24009/document.

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De nombreuses études et écrits ont été réalisés sur le thème du plafonnement de carrière au cours de ces trente dernières années. Cependant, peu se sont penchés sur le degré de volonté qu’une personne peut avoir dans la construction d’un plafonnement de carrière, dès lors que celui-ci apparaît, non pas comme la conséquence de caractéristiques personnelles ou structurelles, mais comme un moyen d’atteindre un objectif précis. Existe-t-il des personnes qui peuvent accepter une situation de plafonnement de carrière ? Y a-t-il des raisons qui les amènent à rechercher une telle situation ? C’est au travers de l’analyse de personnes en situation de plafonnement au sein d’une banque française, que ces questions seront abordées. Les résultats de notre recherche font ressortir une idée maîtresse : l’impact de la présence d’une ou plusieurs ancres de Schein sur les attentes vis-à-vis de la carrière et la volonté d’être en situation de plafonnement. Ces résultats permettent ainsi de proposer un modèle du plafonnement volontaire
Many studies and writings have been made on the them of plateauing career over the last thirty years. However, few have examined the degree of commitment a person can have in builgind a plateauing career, since it appears, not as the result of personal characteristics or structural, but as means achieve a specific objective. Are there peopel who can accept a situation of plateauing career ? Are there reasons that lead them to seek such a situation ? Is it through the analysis of people suffering in plateauing career in a French Bank, that these question will be addressed. The results or our research reveal a key insight : the impact of the presence of one or more Schein anchor’s expectations to the career and will be a plateauing. These results thus suggest a model of voluntary plateau

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Ndiaye, Diarra. "Analyse communicationnelle des systèmes d'information dans le secteur de la santé (2000-2012) : l'exemple de l'implantation de deux logiciels dans les pratiques de la clinique mutualiste La Sagesse de Rennes." Phd thesis, Université Rennes 2, 2013. http://tel.archives-ouvertes.fr/tel-00818188.

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Nous présenterons dans le cadre de cette thèse les résultats d'une étude qualitative basée sur deux logiciels (HôpitalManager et CURSUS 3), implantés à la clinique La Sagesse de Rennes ; étude qui a pour objectif, de souligner les enjeuxcommunicationnels que pose ces outils dans les pratiques cliniques. Ces outils sont considérés aujourd'hui comme des dispositifs de modernisation, de rationalisation, de changementdes pratiques, et des interactions entre le patient, le médecin et les dispensateurs de soins. Ainsi, notre objectif est donc demontrer qu'en plus des enjeux techniques, managériaux, politiques et économiques qui sont identifiés par de nombreuxchercheurs, il existe des défis en termes de communication.Les interrogations que nous soulèverons du point de vue de la recherche en Science de l'Information et de la Communication, autour de ces processus de rationalisation, s'inscriront dans une problématique de changementorganisationnel, de circulation d'information ou encore de normalisation des pratiques professionnelles. Dans cespréoccupations, la technologie déduit tout son raisonnement à partir d'une seule prémisse, celle de la performativité dans les organisations. Ce que nous retenons des travaux d'Orlikowski, réside dans le fait que ce qui compte pour évaluer l'efficacité et la performance d'une technologie n'est pas l'artefact technologique, mais c'est la technologie en pratique(Orlikowski, 2000). Ainsi, notre objectif est de montrer que le discours médico-intégratif, est un énoncé performatif quirepose sur des modalités de communication

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Daguerre, Yohann. "Analyse fonctionnelle d'effecteurs fongiques impliqués dans le développement de la symbiose ectomycorhizienne Laccaria bicolor-Populus trichocarpa." Thesis, Université de Lorraine, 2013. http://www.theses.fr/2013LORR0167/document.

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Les racines de la plupart des arbres forment des symbioses ectomycorhiziennes avec les champignons mutualistes du sol. Le basidiomycète L. bicolor (Maire) P.D. Orton secrète de petites protéines effectrices (MiSSP) afin d'établir les structures symbiotiques. Toutefois, les protéines de l'hôte ciblées par les MiSSPs ne sont pas connues. Dans notre étude, nous démontrons, à l'aide du système double hybride chez la levure (Y2H), que la protéine MiSSP7 interagit avec les co-récepteurs de l'acide jasmonique (AJ) JAZ5 et JAZ6 de P. trichocarpa. Cette interaction entraine un blocage de la voie de signalisation de l'AJ et favorise le développement symbiotique. Des transformants de L. bicolor, dont l'expression de MiSSP7 est fortement réduite, ne sont plus capables de mycorhizer les racines du peuplier. Une variation transgénique de la transcription de PtJAZ6 ou l'inhibition de la voie de signalisation de l'AJ complémente ce phénotype. Nous avons également montré que la protéine PtJAZ6 interagit avec une protéine de type 14-3-3 et un facteur de transcription de type MYC, formant un complexe de régulation. Deux autres protéines effectrices, MiSSP8 et MiSSP17, sont sécrétées et essentielles au développement symbiotique. Les résultats des analyses Y2H suggèrent que MiSSP8 et MiSSP17 pourraient aider au contournement des réactions de défense de la plante-hôte. Au cours du développement symbiotique, le champignon est le siège d'une reprogrammation génétique importante. Les facteurs de transcription (TFs) sont les principaux acteurs de ces changements génétiques. Nous avons donc étudié les TFs de L. bicolor afin d'obtenir un inventaire complet des TFs régulés par la mycorhization
Roots of most trees form symbiosis with mutualistic soil-borne fungi. The ectomycorrhizal basidiomycete L. bicolor (Maire) P.D. Orton relies on mycorrhizal-induced small secreted proteins (MiSSP) to establish symbiotic tissues in the host-plant. The host proteins targeted by these fungal effectors are yet unknown. In the present study, we used the binary yeast two-hybrid (Y2H) system to determine direct interactions between MiSSP7 and the plant proteins in the L. bicolor-P. trichocarpa ectomycorrhizae. We showed that MiSSP7 interact with the jasmonic acid (JA) co-receptors JAZ5 and JAZ6 of P. trichocarpa, blocking JA signaling and promoting mutualism. L. bicolor transformants with severely reduced expression of MiSSP7 did not enter into symbiosis with poplar roots, a phenotype that could be complemented by transgenically varying the transcription of PtJAZ6 or through inhibiting JA signalling. Additional Y2H assays showed that PtJAZ6 protein form a regulatory complex involving 14-3-3 protein(s) and MYC transcriptional factors. Two others L. bicolor effector-like proteins, MiSSP8 and MiSSP17, are secreted and are essential for the symbiosis development. Y2H assays suggested that these MiSSPs interact with plant proteins involved in plant defence signalling pathways. During symbiosis development, L. bicolor experiences important genetic reprogramming required for root colonization. Transcription factors (TFs) are key players of these genetic changes. Here, we developed high throughput analysis of TFs in L. bicolor to obtain a comprehensive inventory of significantly regulated transcription factors in ECM

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Miyashira, Carlos Henrique. "Influência da cafeína na sobrevivência de saúvas Atta sexdens rubropilosa (hymenoptera: Formicidae) e no crescimento in vitro de seu fungo mutualista." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/41/41132/tde-27032008-154811/.

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As formigas cortadeiras (Hymenoptera-Formicidae) estão distribuídas desde o sul dos Estados Unidos até a Argentina. São herbívoros comuns de florestas que coletam material vegetal para cultivar um fungo mutualista específico. São conhecidas pelo seu papel ecológico na aeração do solo, na infiltração da água e na ciclagem de nutrientes. Atividades humanas, como o desmatamento e a agricultura, afetam o ambiente, alterando também o comportamento das saúvas, que acabam atacando os espécimes cultivados. Devido aos prejuízos causados à agricultura, novos inseticidas específicos são necessários. Muitos trabalhos têm sido desenvolvidos usando metabólitos secundários para essa finalidade. Este trabalho tem como objetivo avaliar o efeito da cafeína na mortalidade de Atta sexdens rubropilosa (Forel, 1908) e no crescimento in vitro de seu fungo mutualístico Leucoagaricus gongylophorus (Möller) Singer (Leucocoprineae: Agaricaceae), obtidos de sauveiros mantidos em laboratório. Foram utilizadas quatro concentrações de cafeína, 0,01%, 0,05%, 0,10% e 0,50%. Mortalidade das formigas foi avaliada pelo ensaio de ingestão, acrescentando a cafeína a dietas artificiais sólidas. A cafeína foi incorporada ao meio de cultura para medir a sua influência no crescimento in vitro. Independente das concentrações de cafeína, esse metabólito parece atuar como repelente para a saúvas. A respeito do fungo, quanto maior a concentração de cafeína, menor o crescimento in vitro. Inibição do crescimento foi observada em 0,10% e 0,50% e morte do fungo foi observada em algumas amostras Em conclusão, os resultados sugerem que a cafeína pode ser usada como fungicida, sendo adicionada a iscas que serão coletadas pelas formigas e carregada aos ninhos, causando a redução do fungo e/ou a morte e consequentemente, a morte das formigas.
The leaf-cutting ants (Hymenoptera-Formicidae) are found from south of United States to Argentina. They are common florest herbivorous which collect plant material to feed a specific mutualist fungus. These insects are known by their ecological role at soil aeration, water permeation and nutrient cycling. Human activities, like deforestation and agriculture, affect the environment, affecting the behavior of leaf-cutting ants, which start to attack the crops. Due to crops lost, new specific pesticides are needed. Several researches have been developed using secondary metabolites for this purpose. The present work aimed to evaluate the effect of caffeine at Atta sexdens rubropilosa (Forel, 1908) mortality, and at in vitro growth of the mutualist fungus Leucoagaricus gongylophorus (Möller) Singer (Leucocoprineae: Agaricaceae), collected from laboratory nests. Four caffeine concentrations were tested: 0.01%, 0.05%, 0.10% and 0.50%. Ant\'s mortality was evaluated by ingestion assay, adding caffeine to artificial diets. Caffeine was added to culture medium, to measure its influence on in vitro fungus growth. Despite caffeine concentrations, this compound seems to act as repellent to ants. Concerning to the fungus, the higher the caffeine concentration, the lower the in vitro fungus growth. Growth inhibition was observed at both 0.10% and 0.50% concentrations and death of fungus was observed in some samples. In conclusion, the results suggest that caffeine could be used as fungicide, being added to baits which could be collected by ants and carried to the nests, causing fungus reduction and/or death and consequently, the death of the nests.

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Leite, Douglas Guimarães. "\"Mutualistas, graças a Deus\": identidade de cor, tradições e transformações do mutualismo popular na Bahia do século XIX (1831-1869)." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/8/8138/tde-25102017-161752/.

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No amplo domínio da discussão historiográfica que cobre o tema da população livre de cor ou dos pobres livres, o trabalho se propõe a discutir a inserção social de indivíduos oriundos de setores populares na primeira metade do século XIX na Bahia, debruçando-se especialmente sobre a experiência de homens e mulheres de cor preta, livres ou libertos, nascidos na América, responsáveis por fundar e transformar experiências de mutualismo popular na Bahia do século XIX. A investigação se concentra nas conexões entre as tradições religiosa e secular da ajuda mútua popular promovida por negros no Brasil, por meio da ênfase no estudo das decisões e dos modelos institucionais adotados por integrantes de uma irmandade de pretos fundada em 1832 e de uma sociedade mutual de cor (1851). Saída de uma dissidência entre os irmãos, a Sociedade Protetora dos Desvalidos foi, até onde se sabe, a única mutual autorizada a funcionar oficialmente como uma sociedade de cor, num período de não reconhecimento, e de repressão, da identidade racial de pretos pelo Estado brasileiro.
This thesis aims to discuss the experience of free colour people in Bahia nineteenth century, on the vast theme of popular social mobility that recent historians have been facing in Brazilian historiography. These individuals were black, american born, free or freed men and women, and they helped to create and to change patterns of popular mutual aid in Bahia nineteenth century. This research focuses on connexions between religious and secular traditions of mutual aid of black individual associations by analysing institutional models and strategic decisions made by the members of a black lay sodality founded in 1832 and of a black mutual society, created in 1851. The Sociedade Protetora dos Desvalidos (1851) resulted from a dissidence within the sodality and it was the sole mutual black association officially authorized by the government within an age when black racial identity was not likely to be recognized by Brazilian state.

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Porro, Barbara. "Diversités génétiques chez l’holobiote Anemonia viridis : des morphotypes de l’hôte à la différenciation symbiotique." Thesis, Université Côte d'Azur (ComUE), 2019. http://www.theses.fr/2019AZUR4071.

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Qu’est-ce qu’un individu ? Cette question est un prérequis pour toutes les études en génétique des populations et en biologie évolutive, mais elle est loin d’être naïve dès que l’on prend en compte les relations symbiotiques. Les interactions entre un hôte et ses micro-organismes symbiotiques peuvent conditionner le développement, la reproduction, les capacités adaptatives de l’holobiote qu’ils constituent et donc la trajectoire évolutive de l’espèce. Comprendre ces interactions, c’est appréhender la complexité des interactions symbiotiques et donc caractériser ces différents partenaires et élucider l’implication de chaque partenaire dans le fonctionnement de l’holobiote. Chez les Cnidaires, comme l’anémone de mer Anemonia viridis, les hôtes animaux peuvent établir une symbiose mutualiste avec des Dinoflagellés photosynthétiques de la famille des Symbiodiniacées (avec un seul clade de Symbiodiniacées pour A. viridis). Cette anémone de mer tempérée présente différents morphes caractérisés par la couleur des tentacules. Afin de comprendre la nature de cette diversité phénotypique et mesurer la diversité symbiotique associée chez A. viridis, nous avons génotypé des anémones de Manche et de Méditerranée à l’aide de séquençage RAD (pour l’hôte animal) et de marqueurs ciblés, ITS2 et microsatellites (pour les symbiotes). Nos études ont permis de mettre en évidence l’existence de plusieurs lignées génétiques différenciées en sympatrie chez l’hôte animal, mais qui ne sont pas congruentes avec la différenciation morphologique. La composition des populations de symbiotes in hospite quant à elle n’est pas corrélée avec ces lignées hôtes mais structurées par l’origine géographique des anémones. Ces résultats révèlent qu’A. viridis telle que décrite à l’heure actuelle correspond un complexe d’espèces qui, en plus d’hériter verticalement leurs symbiotes, semblent capables également de les acquérir horizontalement. Cette symbiose dynamique implique que la sélection puisse agir indépendamment aussi bien sur la composition symbiotique que sur l’hôte ; et fait d’A. viridis un excellent modèle pour comprendre les capacités adaptatives d’un holobiote
What is an individual ? This apparently naive question is actually the first step of studies of population genetics and evolutionary biology, but is non-trivial in symbiotic organisms. The interaction among a host and its symbiotic micro-organisms can influence the development, the reproduction and the adaptative capacities of the holobiont and the evolutives trajectories of species. If we want to understand these interactions, we have to decipher the complexity of symbiotic interactions by characterizing the different partners and to measure the role of each partner in the proper functioning of the holobiont. In Anemonia viridis (as in many other Cnidarians), the animal hosts can live in mutualistic symbiosis with photosynthetic Dinoflagellates belonging to the Symbiodiniaceae family (with one Symbiodiniaceae clade for A. viridis). This anemone displays different colour morphs. To understand the origin of the phenotypic diversity but also to measure the associated symbiotic diversity, we genotyped sea anemones from English Channel and Mediterranean Sea with RAD sequencing (for the animal host) and targeted markers, the ITS2 and microsatellite markers (for the symbionts). Our studies revealed several sympatric host genetic lineages which were not congruent with the morphological differentiation. In addition, the symbiotic diversity was not correlated with host genetic lineages but with the sampling location of sea anemones. These results revealed that A. viridis is actually a species complex with both intergenerational vertical transmission and probably an additional horizontal acquisition of Symbiodiniaceae. Because A. viridis shows a dynamic symbiosis, selection can act independently on both the symbiotic composition and the host. This makes A. viridis an interesting laboratory model to understand adaptative capacities in an holobiont

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Georgelin, Ewen. "Couplage entre interactions antagonistes et mutualistes et dynamiques éco-évolutives des communautés." Thesis, Paris 6, 2014. http://www.theses.fr/2014PA066356/document.

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Les communautés écologiques présentent une diversité importante d'organismes et d'interactions. Comprendre le fonctionnement de ces différents types d'interactions constitue l'un des enjeux majeurs de l'écologie des communautés. Cependant, une large majorité des travaux s'intéressant à ces questions s'est focalisée sur les différents types d'interactions séparément. Cette thèse cherche à comprendre comment le couplage entre différents types d'interactions affecte la dynamique des communautés naturelles. Au travers d'une approche théorique, des modèles simples de communautés comprenant deux types d'interactions sont construits. Ces communautés sont constituées de trois espèces : une espèce basale, plante, interagissant avec un antagoniste, herbivore et un mutualiste, pollinisateur. Nous décrivons comment l'effet indirect entre interactions antagonistes et mutualistes affecte les dynamiques écologiques et évolutives des communautés face à une perturbation. Nous montrons que la relation entre pollinisateurs et herbivores à des conséquences importantes pour le maintien éco-Évolutif de la communauté et pour sa stabilité. Nous étudions ensuite la dynamique évolutive de traits particuliers, qui sont impliqués dans chaque type d'interactions. Certains traits attractifs ou de défense des plantes, affectent à la fois les interactions avec les pollinisateurs et les herbivores. Nous montrons comment les pressions de sélection opposées dues à la pollinisation et à l'herbivorie modifient l'évolution de ces traits et peuvent amener à la diversification des plantes
Ecological communities involve an amazing diversity of organisms and interactions. Understanding how this diversity of interaction types (competition, mutualism or predation) affects the ecological and evolutionary dynamics of natural systems is an important challenge of community ecology. However, a large majority of works in community ecology theory considers interaction types separately. This thesis focus on the interplay between antagonism and mutualism. With a theoretical approach, small community models, including antagonistic and mutualistic interactions are built. These communities contain three species : one basal species (a plant) with an antagonist (herbivore) and a mutualistic species (pollinator). First, we study how the indirect effect between the two interaction types affects the ecological and evolutionary dynamics of communities in the currency of a disturbance. Second, we study the evolutionary dynamics of special traits, that are involved in each interaction type. Attractive traits or defensive traits of plants affect both interaction with pollinators and herbivores. We depict how the opposite selective pressures due to pollination and herbivory modify the evolution of these traits and show that they can lead to evolutionary diversification of plants. Following this diversification, the coevolutionary emergence of complex interaction networks is studied

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Maia, Kate Pereira. "Insetos sociais e a estrutura de redes de polinização." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/41/41134/tde-30092014-120347/.

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Mutualismos entre plantas e polinizadores estão organizados em redes de interação que envolvem muitas espécies. Em última instância, o que determina a ocorrência das interações entre plantas e polinizadores são as características dos dois grupos de espécies. O comportamento social pode ser uma das caraterísticas chave na organização das interações em sistemas de polinização. Investigamos se a presença de polinizadores com comportamento social em redes de polinização está associada a diferentes padrões estruturais, e se polinizadores com níveis crescentes de complexidade no comportamento social são mais importantes pra estrutura dessas redes. Encontramos que a variação na proporção de espécies sociais não altera a estrutura de redes de polinização. Encontramos também que espécies com comportamento social são, em média, mais importantes para a estrutura de redes de polinização do que espécies solitárias. Nossos resultados corroboram resultados anteriores que sugerem que redes mutualísticas tem estruturas invariantes. Nossos resultados sugerem ainda que o papel estrutural mais proeminente das espécies sociais está associado à sua maior abundância. Incluir aspectos da história natural das espécies e das interações em estudos de redes ecológicas, nos permitirá fazer inferências cada vez mais assertivas sobre a importância funcional das espécies em comunidades
Mutualisms between plants and pollinators are organized in interaction networks that involve many species. Ultimately, what determines the occurrence of interactions among plants and pollinators are the traits of both groups of species. Social behavior can be a key trait on the organization of interactions between plants and pollinators. Here, we investigated if the presence of pollinators with social behavior in pollination networks is associated to different structural patterns, and if pollinators with increasing levels of complexity in social behavior are more important for network structure. We found that the presence of social pollinator species does not affect the structure of pollination networks. We also found that species with social behavior are, on average, more important for network structure than solitary species. Our results reinforce past studies that suggested that the structure of mutualistic networks has invariant structural properties. Our results also suggest that the more prominent role occupied by pollinators with social behavior is associated to these species\' large abundances. Including natural history information about species and about species interactions on the study of ecological networks will allow us to make more assertive inferences on the functional roles species occupy in ecological communities

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Souza, Roberth Fagundes de. "Competição por mutualismos: hierarquia de dominância interespecífica mediada pela qualidade do recurso regulando interações formiga-planta." Universidade Federal de Uberlândia, 2015. https://repositorio.ufu.br/handle/123456789/13282.

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Fundação de Amparo a Pesquisa do Estado de Minas Gerais
Ants that collect nectar from plants bearing extrafloral nectaries (EFN) can defend them against the attacks of herbivores. Many cases of this food-for-protection mutualism have been described and the next step is to understand the mechanisms that structure these interactions. In this study, this issue was addressed through field observations and experiments on ant behaviour in studies compiled into five chapters. Specifically, we evaluated the plant\'s investment in attracting ants (nectar quality) and the competitive relationship between ants (resource dominance hierarchies) as structuring mechanisms of ant-plant interactions. The entire study took place in areas of the ecosystem known as Rupestrian Fields, located in Ouro Preto (Brazil), between June 2011 and March 2014. In Chapter 1, we observe that ant-plant interaction network in Rupestrian Fields is nested and generalized as expected for mutualisms, but differs from ant-hemipteran network, its ecological equivalent, despite both share ant species interactions. In Chapter 2, we delve into the study of the effect of resources in interaction frequency, and we showed that the quality more than quantity of nectar determines the pattern of interaction between plants (10 species) and ants (32 species), as well as the benefits of this interaction (conditional outcomes). In the Chapter 3, we focus on the ants to demonstrate, using paired encounters, that ants species are organized in dominance hierarchies based on aggressiveness. This hierarchies affects the numerical dominance based on territoriality and, more importantly, in the dominance of interactions and nectar. Keeping this line of thought, we demonstrated in Chapter 4 that not all ants that collect nectar really protect the plant against herbivores but only the ecological dominant and highly interacted species. Finally, we close the thesis demonstrating in Chapter 5 that the ant species interacted with plants during the day are not the same at night, but this diurnal-nocturnal turnover does not affect the structure of the interactions by only changing the dominant species. This study brings behavioural and empirical evidences on the importance of the identity of the ant species and its ecological dominance, as well the effect of the nectar quality, for the structure of ant-plant interactions and effectiveness of mutualisms.
As formigas que recolhem o néctar das plantas com nectários extraflorais (EFN) podem defendê-las contra ataques de herbívoros. Muitos casos desse tipo de mutualismo foram descritos mas ainda é preciso entender os mecanismos que estruturam essas interações. Neste estudo, esse problema foi abordado através de observações de campo e experimentos sobre o comportamento das formigas compilados em cinco capítulos. Especificamente, foi avaliado o investimento da planta em atrair formigas (qualidade do néctar) e a relação competitiva entre formigas pelo néctar (hierarquias de dominância) como mecanismos estruturadores das interações formiga-planta (partição das interações). Todo o estudo ocorreu em áreas do ecossistema Campo Rupestre, localizadas em Ouro Preto (Brasil), de junho de 2011 a março de 2014. No Capítulo 1, observamos que redes de interação formiga-planta em Campo rupestre é aninhada e generalizada como esperado para mutualismos, mas difere da rede formiga-hemíptero, seu equivalente ecológico, apesar de compartilharem as mesmas espécies de formigas interagentes. No Capítulo 2, nós aprofundamos no efeito dos recursos estruturando interações, e mostramos que a qualidade mais do que a quantidade de néctar determina o padrão de interação entre formigas (32 espécies) e plantas (10 espécies), bem como os benefícios desta interação (benefícios condicionais). No Capítulo 3, nós demonstramos através de encontros interespecíficos pareados que as formigas são organizadas em hierarquias de dominância comportamental baseadas em agressividade. Essa hierarquia afeta a dominância numérica por territorialidade e, mais importante, o domínio das interações e do néctar. Mantendo esta linha de pensamento, demonstramos no Capítulo 4 que nem todas as formigas que coletam néctar realmente protegem a planta contra herbívoros mas somente as espécies dominantes e altamente interagidas. Finalmente, fechamos a tese demonstrando no Capítulo 5 que as espécies de formiga que interagem com as plantas durante o dia não são o mesmo à noite, mas esta rotatividade diurno-noturno não afeta a estrutura das interações devido a troca específica da formiga dominante. Este estudo traz evidências comportamentais e empíricas sobre a importância da identidade de espécies de formiga e sua dominância ecológica, assim como da qualidade do recurso, para a estrutura de rede da formiga-planta e eficácia do mutualismo.
Doutor em Ecologia e Conservação de Recursos Naturais

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Mota, Luísa Lima e. 1989. "Ant-treehopper associations as visual cues for egg-laying Parrhasius polibetes (Lepidoptera: Lycaenidae), a facultative myrmecophilous butterfly = Associações formiga-membracídeo como pistas visuais para oviposição em Parrhasius polibetes (Lepidoptera: Lycaenidae), uma borboleta mirmecófila facultativa." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/316178.

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Orientador: Paulo Sérgio Moreira Carvalho de Oliveira
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: A escolha do local de oviposição tem grande influência na aptidão das fêmeas de Lepidoptera, uma vez que as larvas têm mobilidade restrita. Pistas químicas, visuais e/ou táteis provindas da planta hospedeira costumam ser utilizadas, mas também são importantes a presença de inimigos naturais ou parceiros mutualistas. No caso de espécies mirmecófilas, a oviposição pode ser mediada pelas formigas atendentes, mas pouco se sabe sobre como as borboletas percebem as formigas e as utilizam como sinal. Parrhasius polibetes, um licenídeo polífago que apresenta mirmecofilia facultativa, é comumente encontrada em Schefflera vinosa (Araliaceae), uma planta que também pode abrigar agregações do membracídeo Guayaquila xiphias. P. polibetes e G. xiphias podem ser atendidas pelas mesmas formigas, e larvas de P. polibetes tem sua sobrevivência aumentada quando ocorrem próximas às associações G. xiphias + formigas, e as borboletas adultas preferem ovipositar em ramos onde a associação está presente, embora não se conheça qual sinal é utilizado para essa escolha. Este trabalho teve por objetivo investigar se P. polibetes reconhece visualmente a associação e a utiliza como pista para oviposição. Foram feitos experimentos com formigas e membracídeos secos montados em ramos pareados de S. vinosa, entre os quais a borboleta poderia escolher. Fêmeas de P. polibetes preferiram ovipositar em ramos contendo a pista visual de formigas + membracídeos ou apenas de formigas, não havendo preferência quando apenas membracídeos estavam presentes. O número de ovos foi maior apenas quando a pista visual de formigas + membracídeos estava presente. Isso revela a importância da visão para a escolha do local de oviposição por P. polibetes, embora não se descarte o uso de pistas químicas ou táteis. A imagem de formigas deve ser recorrente em muitas espécies de plantas hospedeiras utilizadas por P. polibetes, e fêmeas capazes de utilizá-la na hora da oviposição teriam vantagem dada a importância das formigas para a sobrevivência das larvas. As pistas utilizadas por borboletas com diferentes níveis de mirmecofilia para escolha do local de oviposição representam um campo de estudo pouco explorado, que poderá revelar novos aspectos sobre a interação entre lepidópteros e formigas
Abstract: Because the larvae have restricted mobility, the location chosen for oviposition and immature development may have a crucial effect on Lepidoptera fitness. Chemical, visual and/or tactile cues from the host plant are usually utilized during host plant selection, but the presence of natural enemies or mutualistic partners is also important. In the case of myrmecophilous species, oviposition can be mediated by the tending ants, but little is known about how the female perceive ants, and use them as cues. Parrhasius polibetes, a poliphagous lycaenid that presents facultative myrmecophily, is commonly found in Schefflera vinosa (Araliaceae), a bush commonly hosting aggregations of the treehopper Guayaquila xiphias. P. polibetes and G. xiphias can be tended by the same ants, and P. polibetes larvae have their survivorship increased when they occur close to associations of G. xiphias + ants. Female butterflies prefer to oviposit on branches where the association is present, even though the signal used in this choice is unknown. The objective of this study was to investigate whether P. polibetes visually recognize ant-treehopper associations and use them as clue for oviposition. Behavioral trials consisted of dried ants and treehoppers mounted on paired S. vinosa branches, between which the butterfly could choose. P. polibetes females preferred to oviposit on branches containing ants + treehoppers or only ants, and showed no preference when only treehoppers were present. The number of eggs was greater only when both ants and treehoppers were present on a branch. These results reveal the importance of vision during the oviposition process in P. polibetes, even though chemical and tactile clues may also be used. The image of ants is probably recurrent in many host plant species used by P. polibetes, and females capable of perceiving them during oviposition would have an advantage, given the importance of ants for larval survival in this species. So far, the cues used during egg-laying by butterflies with different levels of myrmecophily have not been explored in detail; and further investigations might reveal new aspects about the behavioral interface of butterfly-ant interactions
Mestrado
Ecologia
Mestra em Ecologia

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23

Soler, Catherine. "Parfum de figues : approche évolutive de la communication entre une plante, ses insectes pollinisateurs et ses vertébrés disperseurs." Thesis, Montpellier 2, 2010. http://www.theses.fr/2010MON20229/document.

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Pour l'ensemble des organismes vivants, la communication (intra ou interspécifique) est le véhicule de l'information, un élément central dans l'interaction entre individus. Elle a ainsi des impacts primordiaux sur les traits d'histoire de vie des espèces, et est donc façonnée par la sélection naturelle. Au cours de cette thèse, nous nous sommes intéressés à l'évolution de la médiation chimique, c'est-à-dire à la transmission d'informations par voie chimique entredeux individus, dans les interactions plantes/animaux. Nous avons choisi le modèle figuier et ses partenaires mutualistes, de la guêpe pollinisatrice aux vertébrés disperseurs de graines. La médiation chimique (ici émission de bouquets volatils constitués de terpènes et de dérivés benzéniques et d'acides gras) permet aux figuiers d'assurer leur reproduction, par attraction des pollinisateurs et des disperseurs de graines. Il existe environ 800 espèces de figuiers à travers le monde, à distribution principalement tropicale. Les figuiers, fructifiant toute l'année,sont souvent qualifiés d'espèce clef de voute des écosystèmes tropicaux, car ils assurent ainsi le maintien des populations de frugivores dans les forêts tropicales dans les périodes où très peu d'espèces d'arbres fructifient. L'interaction figuier/disperseur est plutôt généraliste, alors que le mutualisme figuier/pollinisateur, un exemple de nursery pollination, est hautement spécifique et obligatoire. Au cours de cette thèse, nous avons mis en évidence que les contraintes phylogénétiques et géographiques exercées sur la médiation chimique étaient négligeables, alors que les pressions de sélection que représentent les mutualistes sont nettement plus importantes dans l'évolution de cette médiation. Ainsi, sexe et stade phénologique du figuier et identité du partenaire mutualiste sont des informations qui peuvent être portées par la médiation chimique. Notre approche, globale et multidisciplinaire, des interactions entre les figuiers et leurs partenaires mutualistes aux deux phases de dispersions des gènes de la plante, permet une meilleure compréhension de l'évolution de la communication, et montre que les pressions façonnant ce message façonnent l'interaction elle-même
For all living organisms, communication (intra-or interspecific) is the vehicle of information, anelement central to interactions among individuals. It thus has fundamental impacts on lifehistory traits of species, and is shaped by natural selection. This thesis is concerned with thechemical mediation of communication, i.e., the transmission of information by chemical signals,in the context of animal-plant interactions. We chose as a model system the interactionsbetween figs and their mutualist partners, including both pollinating fig wasps and vertebrateseed dispersers. Chemical mediation (in this case the emission of bouquets of volatilecompounds comprising terpenes, benzenoids and fatty acid derivatives) enables figs to ensuretheir reproduction by attracting pollinators and seed dispersers. There exist about 800 species ofFicus worldwide, principally in tropical regions. Figs, which fruit throughout the year, are oftenconsidered keystone species of tropical ecosystems, because their year-round fruiting maintainspopulations of seed-dispersing frugivores during fruit-poor lean seasons'. Interactions betweenfig species and seed-dispersing animals are generalist' (i.e., broad food species ranges), whilefig/pollinator mutualisms, examples of nursery pollination' systems, are highly species-specificand obligatory. In this thesis, we showed that phylogenetic and geographic constraints actingon chemical mediation are negligible, whereas selection pressures grounded in pollination andseed-dispersal mutualisms play a strong role in shaping the evolution of chemical mediation.Thus, chemical mediation carries information such as the sex and developmental stage of thefig tree, as well as the identity of the mutualistic partner. Our comprehensive, multidisciplinaryapproach to interactions between figs and their mutualist partners in the two phases ofdispersal of the plant's genes leads to an improved understanding of the evolution ofcommunication, and showed that the selective pressures shaping the message are also thoseshaping the interaction itself

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Largo, Jiménez Fernando. "Mutualismo y capital social. El papel de la federación de mutualidades de Cataluña, 1896-1936." Doctoral thesis, Universitat Autònoma de Barcelona, 2017. http://hdl.handle.net/10803/455148.

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En el presente trabajo, se aplica el marco teórico del capital social al estudio del mutualismo de trabajadores en España durante el primer tercio del siglo XX, periodo en el que alcanzó su auge y su declive. Se utilizan varios enfoques: el expansionista, centrado en la capacidad de las redes sociales para generar confianza y facilitar la acción colectiva y el meso, que destaca los recursos que fluyen dentro de las redes. Dependiendo de factores estructurales y relacionales (tamaño, verticalidad y horizontalidad, homogeneidad social, proximidad geográfica) se analiza su capacidad para generar confianza y reciprocidad y para facilitar el acceso a los recursos. Se explora la evolución de las diferentes categorías de mutualidades clasificándolas entre tres: democráticas, asistenciales, y burocráticas. Las sociedades democráticas eran horizontales, autogestionadas, autofinanciadas y de pequeño tamaño. Las asistenciales, eran verticales, favorecidas financieramente por notables de una clase social superior. Por último, las burocráticas eran verticales y con un funcionamiento más técnico, en las que el capital social era menos relevante. Se apuntan los criterios para determinar a qué categoría pertenece una sociedad dada, lo que posibilita un estudio más en profundidad del desarrollo institucional del mutualismo español. A continuación, se analiza el declive de las sociedades democráticas (determinantes para el desarrollo del capital social) en favor de las burocráticas, utilizando para ello un estudio de caso sobre la provincia de Barcelona durante el primer tercio del siglo XX. Partiendo de la hipótesis de que los citados factores estructurales y relacionales condicionaron el funcionamiento de las sociedades de socorros mutuos como instituciones de acción colectiva corporativa, se reconstruye su evolución a través del estudio de variables como el tamaño o la composición de los gastos, de forma complementaria a las explicaciones basadas en los efectos de la competencia o en el papel del Estado. Se determina que las mutualidades democráticas cumplían las condiciones facilitadoras de la sostenibilidad institucional, pero su condición de sociedades aseguradoras generó contradicciones que resultaron perjudiciales. El examen del cumplimiento de estas condiciones, permite estimar la transformación del mutualismo de trabajadores en la provincia y el papel que jugaron los factores exógenos (la intervención pública, los cambios sociales y económicos y la competencia en el mercado de la previsión). Debido a su finalidad previsora, las sociedades de socorros mutuos constituyen un tipo de asociacionismo adecuado para revisar la existencia del efecto crowding-out entre el Estado del bienestar y el capital social. Aunque en el caso español tal efecto acabó produciéndose, éste debe matizarse, ya que cuando los seguros sociales públicos supusieron una competencia real para el mutualismo, éste ya había experimentado un proceso de concentración y profesionalización y las mutualidades democráticas habían quedado relegadas por las burocráticas. Posteriormente, se estudia la evolución global de la Federación de Mutualidades de Cataluña entre 1896 y 1936, que resulta también de utilidad para estimar la evolución del mutualismo a través de su composición. A través de iniciativas, la Federación permitió a las sociedades que la integraban compatibilizar las ventajas de un tamaño pequeño (creación de confianza y reciprocidad, reducción de los costes de supervisión) con el acceso a los recursos de una red mayor. Se analizan los servicios puestos a disposición de las sociedades adheridas, las actividades realizadas o las relaciones con otras instituciones, prestando especial atención a los efectos de sus iniciativas sobre el capital social. En definitiva, la presente tesis supone una revisión de la evolución del mutualismo obrero a través del marco del capital social, que ofrece nuevas expectativas para su estudio.
In the present work, the theoretical framework of social capital is applied to the study of worker’s mutualism in Spain during the first third of the twentieth century, when it reached its peak and its decline. Some approaches are used: the expansionist, focused on the capacity of social networks to build trust and facilitate collective action and the meso, which highlights the resources flowing within networks. Depending on structural and relational factors (size, verticality and horizontality, social homogeneity, geographical proximity), their ability to generate trust and reciprocity and to facilitate access to resources is analyzed. The evolution of the different categories of mutual aid societies is explored, classifying them as three: democratic, assistential, and bureaucratic. Democratic societies are characterized by small size, horizontal, self-managed and self-financed. The assistential ones were vertical, favored financially by notables of a superior social class. Finally, the bureaucratic ones were vertical and with a more technical operation, in which the social capital was less relevant. The criteria for determining the category of a given society are pointed out, which enables a more in-depth study of the institutional development of Spanish mutualism. Next, we analyze the decline of democratic societies (determinants for the development of social capital) in favor of bureaucratics, using a case study on the province of Barcelona during the first third of the twentieth century. Based on the hypothesis that the structural and relational factors conditioned the functioning of mutual aid societies as institutions of corporate collective action, their evolution is reconstructed through the study of variables such as size or composition of expenditures, complements the explanations based on the effects of competition or on the role of the State. It is determined that democratic mutual societies fulfilled the conditions facilitating institutional sustainability, but their status as insurance companies generated contradictions that were detrimental. Examination of compliance with these conditions makes it possible to estimate the transformation of worker’s mutualism in the province and the role played by exogenous factors (public intervention, social and economic changes and competition in the social welfare market). Because of their insurer purpose, mutual aid societies are a kind of associations suitable for reviewing the existence of the crowding-out effect between welfare state and social capital. Although in the Spanish case such an effect ended up, this should be qualified, since when public social insurances supposed a real competition for mutualism, it had already undergone a process of concentration and professionalization and democratic mutualities had been relegated by bureaucratic. After that, the overall evolution of the Federation of Mutualities of Catalonia between 1896 and 1936 is studied, which is also useful to estimate the evolution of mutualism through its composition. Through initiatives, the Federation allowed its member mutualities to combine the advantages of a small size (building trust and reciprocity, reducing supervision costs) with access to the resources of a larger network. It analyzes the services made available to the member societies, the activities carried out or the relations with other institutions, paying attention to the effects of their initiatives on social capital. In short, this thesis implies a revision of the evolution of workers' mutualism through the framework of social capital, which offers new expectations for its study.

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25

Barros, Irina Birskis. "Evolutionary dynamics of mimetic rings in heterogeneous ecological communities." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/41/41134/tde-03102017-102248/.

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Müllerian mimicry theory postulate that individuals of different species benefit from decreased per-capita attack risks by sharing similar warning signals. In species-rich mimetic assemblages, there is the formation of several distinct sympatric groups of species sharing the same warning signals, often color pattern, called mimetic rings. The coexistence of multiple rings seems paradoxical considering that selection among unpalatable species should favor convergence and thus reinforce a single color pattern. Different rings evolving in distinct habitats could explain the coexistence of multiple mimicry rings. However, the way species use the habitats might influence the emergence of multiple mimicry rings. We combined mathematical modeling and numerical simulations to explore how habitat heterogeneity, abiotic selection and habitat generalist species influence the formation of mimicry rings in a community. We showed that distinct selection pressures, derived from habitat heterogeneity, favored the formation of distinctive mimicry rings. Nevertheless, just the co-existence of species was enough to drive the emergence of the rings. Simulations in which there was just biotic or abiotic selection, time for convergence was faster than when both sources of selection acted together, suggesting conflicting selective pressures exerted by environment and co-existing species. In the presence of species that was habitat generalist, species converged to similar trait values, decreasing the distinctiveness of mimicry rings. A unique mimicry ring was formed if the different habitats optima in the community were very similar or when most species were habitat generalists. Our results suggest that multiple sympatric mimicry rings are formed by a complex interplay between abiotic and biotic selection and is only possible in groups of animals in which local species composition is strongly affected by habitat heterogeneity such as butterflies
No mimetismo Mülleriano, indivíduos de diferentes espécies, ao compartilharem um mesmo sinal de advertência, beneficiam-se mutuamente devido ao menor risco de predação. Em comunidades ricas em mímicos há a formação de grupos simpátricos de espécies denominados anéis miméticos, que compartilham os mesmos sinais de advertência, como por exemplo padrões de coloração. A coexistência de anéis miméticos parece paradoxal, uma vez que, em teoria, a seleção favoreceria a convergência das espécies impalatáveis e, portanto, geraria um único padrão de cor. A evolução de diferentes anéis miméticos em habitats distintos poderia explicar a coexistência desses anéis em uma comunidade. No entanto, a maneira como as espécies utilizam esses habitats talvez influencie também a emergência dos múltiplos anéis miméticos. Utilizamos modelos matemáticos e simulações computacionais para melhor compreender como a heterogeneidade de habitats, a seleção ambiental e espécies generalistas de habitat influenciam a formação de anéis miméticos em uma comunidade. Demonstramos que diferentes pressões seletivas, derivadas de uma heterogeneidade de habitats, podem favorecer a formação de anéis miméticos. Porém, a simples coexistência das espécies é suficiente para a emergência de anéis. Em simulações nas quais só havia seleção imposta por espécies impalatáveis ou pelo ambiente, o tempo de convergência foi mais rápido do que quando as duas forças seletivas atuavam juntas. Isto demonstra que provavelmente há conflito entre a seleção biótica e abiótica, não favorecendo o mesmo ótimo fenotípico. A presença de uma espécie generalista de habitat favoreceu a convergência de espécies para um valor fenotípico similar, diminuindo a distinção entre os anéis. Um único anel foi formado quando os diferentes fenótipos favorecidos pela seleção imposta pelo ambiente eram muito similares entre habitats, ou quando muitas espécies eram generalistas de habitat. Nosso trabalho sugere que múltiplos anéis miméticos simpátricos são formados por uma complexa interação entre seleção biótica e abiótica e que só são possíveis em grupos no qual a diversidade é estruturada em pequenas escalas espaciais, como borboletas

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Gomes-Silva, Flavio. "Evolução de acarodomácias em Bignonieae (Bignoniaceae)." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/41/41132/tde-24022010-112022/.

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Acarodomácias (ou domácias foliares) são cavidades ou tufos de tricomas localizados nas axilas entre as nervuras na face abaxial das folhas. Por meio dessas estruturas, várias espécies de angiospermas lenhosas estabelecem um mutualismo com ácaros benéficos (fungívoros e predadores). Nessa simbiose, as domácias foliares fornecem abrigo e proteção aos ácaros contra inimigos naturais e dessecação, enquanto os ácaros protegem as plantas contra fungos patogênicos e artrópodes fitófagos. Essas estruturas estão presentes em várias espécies da tribo Bignonieae (Bignoniaceae), um grupo monofilético com cerca de 382 espécies de lianas e arbustos neotropicais. A notável variedade de acarodomácias na tribo, somada à disponibilidade de uma filogenia robusta do grupo, torna Bignonieae um excelente modelo para investigar a evolução dessas estruturas. O presente trabalho visou caracterizar as acarodomácias de Bignonieae e estudar a evolução dessas estruturas no grupo. Além disso, realizou testes de correlação entre a evolução de acarodomácias e a de outras características potencialmente associadas à acarofilia: pilosidade foliolar e nectários extraflorais (NEFs). As acarodomácias estão presentes em 58 das 103 espécies analisadas, abrangendo 12 dos 20 gêneros da tribo presentes na filogenia. Foi constatada a presença de domácias primárias, secundárias e terciárias, e dos componentes bolso, tricomas e cova. A variação intra-específica constatada para esses caracteres foi marcante. Além disso, todos eles revelaram-se homoplásticos (múltiplas evoluções e reversões). Foi encontrada uma correlação positiva entre os padrões de evolução de domácias primárias, secundárias e terciárias, e um surgimento sequencial dessas estruturas: primeiro surgiram as domácias primárias, depois as secundárias e, por fim, as terciárias. Quanto aos componentes, bolso e tricomas mostraram-se onipresentes e revelaram uma evolução correlacionada; a evolução do componente cova, por sua vez, não se mostrou correlacionada a dos outros componentes. O padrão de evolução de pilosidade foliolar revelou que, em geral, primeiro surgiram tricomas sobre as nervuras e, posteriormente, os tricomas se estenderam pela lâmina. A evolução de acarodomácias também se mostrou correlacionada à de pilosidade foliolar. É possível que a pilosidade e as acarodomácias atuem em conjunto no mutualismo planta-ácaro benéfico. Adicionalmente, constatou-se que as evoluções de acarodomácias estão sempre relacionadas à presença de tricomas, sugerindo que os tricomas devem ter uma papel especial na acarofilia. Não se observou correlação entre a evolução de domácias foliares e a de NEFs. Este estudo representa o primeiro trabalho sobre a evolução de acarodomácias, e traz importantes subsídios para pesquisas futuras sobre diferentes aspectos da biologia dessas estruturas em Bignonieae, especialmente no que tange a interação planta-ácaro benéfico.
Acarodomatia (or leaf domatia) are cavities or hair tufts found on the axils of veins on the abaxial surface of leaves. Several species of woody angiosperms mediate a mutualism with benefic mites (fungivorous and predaceous) through these structures. In this symbiotic relation, the leaf domatia provide refuge and protection to mites against natural enemies and desiccating conditions, while the mites protect the plants against pathogenic fungi and phytophagous arthropods. These structures are present in many species of the tribe Bignonieae (Bignoniaceae), a monophyletic group with approximately 382 species of neotropical lianas and shrubs. The wide variation of acarodomatia in the tribe associated with the availability of a robust phylogeny for the group makes Bignonieae an excellent model to address the evolution of these structures. The objective of this study was to characterize the acarodomatia of Bignonieae and investigate the evolution of these structures in the group. Furthermore, this study intended to test for correlated patterns of evolution between leaf domatia and traits potentially associated with acarophily: leaflet pubescence and extra floral nectaries (EFNs). Acarodomatia were found in 58 of the 103 analyzed species, representing 12 of the 20 genera of Bignonieae sampled within the phylogeny of the group. Primary, secondary and tertiary domatia were encountered, as well three different domatia components: pocket, trichomes and pit. High intraspecific variation was encountered in those traits. Furthermore, high homoplasy was also encountered, with multiple evolutions and reversals of each trait being documented. A positive correlation in the pattern of evolution of the primary, secondary and tertiary domatia was found, as well as a sequential evolution of these structures: first primary domatia evolved, which was followed by the evolution of secondary domatia and, subsequently the evolution of tertiary domatia. As far as the components of the acarodomatia are concerned, pockets and trichomes were omnipresent and their evolutionary pattern correlated. The evolution of the pit, on the other hand, was not associated to the evolution of any of the other components. The evolutionary pattern of leaf pubescence indicated that, in general, trichomes over the veins of the leaflets evolved first and subsequently spread throughout the blade. The evolutionary pattern of acarodomatia was also shown to be correlated with the evolution of leaflet pubescence. It is possible that pubescence and acarodomatia might act together to promote a beneficial plant-mite mutualism. In addition, the multiple origins of the acarodomatia were always associated with the presence of trichomes, suggesting that trichomes must have had an important role in acarophily. No correlation was found between the evolution of leaf domatia and the evolution of EFNs. This study represents the first investigation of the evolution of acarodomatia, and brings important contributions for future studies on different aspects of the biology of these structures in Bignonieae, especially in what concerns the beneficial association between plants and mites.

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Dufaÿ, Mathilde. "Conflits d'intérêts et rencontres des partenaires du mutualisme : le cas du mutualisme palmier nain / pollinisateur." Montpellier, ENSA, 2003. http://www.theses.fr/2003ENSA0009.

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Les mutualismes sont omniprésents dans la nature, mais les conflits d'intérêts qui opposent les partenaires peuvent rendre ces interactions instables. Certaines études théoriques issues de la théorie des jeux ont souligné l'importance du processus de la rencontre des partenaires pour la stabilité évolutive des mutualismes. Le but de cette étude était de comprendre, par une approche expérimentale, comment les conflits d'intérêts entre partenaires et l'émission des signaux facilitant leur rencontre à chaque génération agissent sur la stabilité des mutualismes à transmission horizontale. Nous avons étudié le mutualisme entre le palmier Chamaerops humilis et son pollinisateur spécifique Derelomus chamaeropsis, qui se reproduit dans les inflorescences de sa plante hôte. Dans ce mutualisme, les plantes femelles sont « tricheuses» ; elles détruisent les oeufs des pollinisateurs, induisant ainsi un phénomène de pollinisation par tromperie, très coûteux pour le pollinisateur, et qui constitue une source d'instabilité pour l'interaction. L'étude du mode d'attraction des pollinisateurs chez C. Humilis a révélé un système inconnu jusqu'alors chez les angiospermes ; les pollinisateurs sont attirés par des composés volatils émis par les feuilles, et non par les fleurs. Une première étude comparée suggère que ce mode d'attraction pourrait avoir évolué dans des conditions écologiques particulières chez quelques espèces de palmiers. Par ailleurs, le signal olfactif présente un dimorphisme sexuel sur la quantité de composés volatils. Ce dimorphisme conduit les pollinisateurs à rencontrer plus fréquemment le signal émis par les plantes mâles et à les visiter plus souvent. Toutefois, nous avons montré que la composition chimique du signal était extrêmement variable entre individus. Cette variabilité élude toute possibilité de différencier qualitativement les signaux mâles des signaux femelles et empêche l'évolution d'un comportement de choix actif chez le pollinisateur. Notre étude empirique va à l'encontre des prédictions théoriques et montre que l'incapacité d'un partenaire à « punir» les « tricheurs» peut paradoxalement stabiliser un mutualisme. Ceci s'explique en partie par le fait qu'une espèce mutualiste n'est pas forcément un ensemble homogène d'individus. Ici, les divergences d'intérêts entre plantes mâles et femelles non seulement caractérisent les conflits d'intérêts avec le troisième partenaire (le pollinisateur), mais déterminent également la dynamique évolutive de l'interaction
Mutualisms are ubiquitous in nature, but according to current theory the conflicts of interest between mutualists should make these interactions unstable. Studies based on game theory have underlined the importance of the process of partner encounter in determining the evolutionary stability of mutualisms. The aim of this study was to understand, using an experimental approach, how the conflicts of interest between partners in a horizontally transmitted mutualism, and the emission of signals facilitating partner encounter in each new generation, interact to affect the evolutionary stability of the mutualism. We studied the mutualism between the paIm Chamaerops humilis and its specifie pollinator Oere/omus chamaeropsis, which reproduces inside the inflorescences of its host plant. Ln this mutualism, female plants are "cheaters"; they kill the eggs of their pollinator, leading to a phenomenon of pollination by deceit, imposing high costs on the pollinator and constituting a potential source of instability for the interaction. Our study of the mode of pollinator attraction by C. Humilis has revealed a unique system, previously unknown in angiosperms. The pollinators are attracted by volatile compounds emitted by leaves, and not by flowers. A preliminary comparative study suggests that this mode of attraction may have evolved more than once in palms, under particular ecological conditions. Furthermore, the chemical signal released shows sexual dimorphism in the total quantities of volatile compounds emitted by plants. This difference leads the pollinator to encounter male plants more frequently and to visit them more often. However, we showed that the chemical composition of the signal was extremely variable among individuals, excluding any possibility of qualitative distinction between signals emitted by male and female plants and preventing the evolution of an active choice behaviour by the pollinator. Our results contradict predictions from theory and show that the inability of a partner to "punish cheaters" can paradoxically stabilise a mutualism. The paradox is partly explained by the fact that the population of a mutualist is not necessarily a homogeneous set of individuals. In this system, the divergence of interests between male and female plants not only conditions the conflict of interests with the third partner (the pollinator), but also determines the evolutionary dynamics of the interaction

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28

Mestvedt, Borgen Sigrun. "Urban Mutualism." Thesis, KTH, Arkitektur, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-298804.

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The city of Stockholm has set the goal to build 140 000 new residential units by 2030 to meet the demand of a growing urban population. Simultaneously we are seeing a decline in biodiversity in and surrounding the city. Some of the main factors are climate change, pollution, overexploitation and habitat destruction. As cities grow, they have the potential to aid or accelerate these problems, depending on how this urban growth is approached.In current urban development projects in Stockholm, we increasingly see large scale, high exploitation projects that view efficiency and profitability as their main goal. Biodiversity is largely considered an afterthought. We are chipping away at natural habitats and infrastructure, which has dramatic consequences for other species and ultimately ourselves.This thesis is a study on the city’s impact on biodiversity, and how new developments in Stockholm relate to our surrounding ecosystems. It is an investigation of how we, as urban dwellers, can live with nature. It is also an exploration of how we, as architects and urban planners, can shape cities for urban mutualism.

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Guimarães, Junior Paulo Roberto. "Estrutura das redes de interações mutualisticas." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/316228.

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Анотація:

Orientadores: Sergio Furtado dos Reis, Marcus A. M. de Aguiar
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: INTRODUÇÃO: mutualismos são interações entre espécies diferentes que beneficiam os indivíduos envolvidos. Em uma comunidade ecológica, mutualismos tais como interações entre plantas e polinizadores e entre plantas e dispersores de sementes podem ser descritas como uma rede. O estudo dessas redes de interações levou à descrição de duas propriedades estruturais gerais: (1) a probabilidade de se encontrar uma espécie com k interações decai seguindo uma lei de potência com truncamento exponencial e (2) aninhamento. Essas duas propriedades estão, aparentemente, ausentes em interações entre predadores e presas, as chamadas teias tróficas. OBJETIVOS: contribuir para a compreensão dos processos subjacentes aos padrões observados em redes mutualísticas e investigar o grau de generalização desses padrões. PRINCIPAIS RESULTADOS: ¿ A lei de potência truncada que caracteriza a distribuição do grau de redes mutualísticas pode ser explicada por condições iniciais aleatórias e por processos associados à diferença de riqueza entre plantas e animais. ¿ A estrutura aninhada de uma rede mutualística é parcialmente explicada por diferenças entre as abundâncias das espécies. ¿ Problemas de resolução taxonômica característica de estudos sobre teias tróficas, mas pouco comuns no estudo de mutualismos, explicam as diferenças nas distribuições do grau desses dois tipos de redes ecológicas. A ausência de aninhamento, todavia, não é explicada por este problema de resolução. ¿ As redes que descrevem outros dois mutualismos, as interações entre limpadores e clientes em recifes de corais e entre formigas e plantas produtoras de néctar extrafloral, são aninhadas. PRINCIPAIS CONCLUSÕES: a forma da distribuição do grau observada em mutualismos é esperada por processos simples e gerais. O aninhamento é uma propriedade geral de mutualismos em comunidades ricas de espécies
Abstract: Not informed.
Doutorado
Doutor em Ecologia

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30

Zagatto, Maurício Rumenos Guidetti. "Mesofauna edáfica em plantios puros e mistos de Eucalyptus grandis e Acacia mangium." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/11/11140/tde-25072018-175726/.

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A mesofauna edáfica compreende pequenos invertebrados que vivem nos primeiros centímetros do solo e na serapilheira. Sabe-se que o plantio de leguminosas com espécies arbóreas não fixadoras de nitrogênio melhora a fertilidade do solo, porém não se conhece o efeito desses plantios nos invertebrados edáficos. Diante disso, objetivou-se, com este estudo, avaliar o efeito de plantios puros e mistos de Eucalyptus grandis e Acacia mangium na mesofauna edáfica e estabelecer relações da mesofauna com os atributos químicos do solo e da serapilheira e os microbiológicos do solo, a fim de se construir um novo indicador de qualidade do solo. Para tanto, em outubro de 2015 (estação seca) e março de 2016 (estação chuvosa) foram avaliados os atributos físico-químicos da serapilheira (Ca, Mg, N, P, C, C/N, C/P, Mn, Cu, Fe, Zn, umidade), microbiológicos do solo (C mic, respiração do solo e atividade da desidrogenase), a umidade do solo e a mesofauna do solo e da serapilheira (riqueza, densidade e diversidade de mesofauna). Já os atributos químicos do solo (pH, Ca, Mg, C, N, P, Al, H+Al, Na, K) foram avaliados apenas em outubro. A média dos atributos foi comparada pelo teste de Tukey a 5%, enquanto que correlações, regressões e análises multivariadas foram feitas para estabelecer relações entre a mesofauna e os atributos do solo e da serapilheira e, posteriormente, construir um indicador geral de qualidade do solo. A fauna que habita a serapilheira, os atributos microbiológicos do solo e o indicador geral de qualidade do solo apresentaram maiores valores na estação chuvosa. A umidade foi muito correlacionada com os atributos biológicos do solo e da serapilheira. Foram também constatadas diferenças entre tratamentos, sendo que na estação seca há preferência da mesofauna pelo hábitat solo, possivelmente com a prevalência de relações mutualísticas entre microrganismos e mesofauna, enquanto há uma expressiva preferência da mesofauna pela serapilheira durante a estação úmida.
Soil mesofauna comprises small invertebrates that live in the first centimeters of the soil and in the litter. The consortium between leguminous trees and non-nitrogen-fixing tree species improves soil fertility, but the effect of these plantations on edaphic invertebrates is not known yet. Thus, we aimed at evaluating the effect of pure and mixed plantation of Eucalyptus grandis and Acacia mangium on the invertebrates that inhabit the soil and litter. We looked for correlations between those plantations, soil and litter chemical attributes and soil microbiological attributes to create a general indicator of soil quality in Acacia mangium (AC), Eucalyptus grandis (EU) and mixed plantations of Acacia and Eucalyptus (M). The chemical litter attributes evaluated were Ca, Mg, N, P, C, C/N, C/P, Mn, Cu, Fe, Zn, besides soil and litter moisture, soil microbiology (microbial carbon, soil respiration and dehydrogenase activity) and soil and litter mesofauna (richness, density and diversity) in two seasons: October 2015 (dry season) and March 2016 (rainy season). Soil chemical analyses (pH, Ca, Mg, C, N, P, Al, H+Al, Na, and K) were from samples collected in October. We made comparisons of the means between forest systems, and established a general indicator of soil quality based on regressions and multivariate analyses, to identify correlations between mesofaunaand chemical and microbiological attributes. Litter mesofauna, microbial activity and the general indicator of soil quality presented much higher values in the rainy season than in the dry season. Moisture correlated positively with most of the soil and litter biological attributes. There were few differences between the forest systems; although we observed a clear mesofauna preference for soil as habitat in the dry season, possibly linked to the prevailance of mutualistic interactions between soil mesofauna and microorganisms, while the mesofauna showed great preference for the litter as habitat during the moist season.

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31

Aubier, Thomas G. "Diversity of warning signals, speciation and clade diversification." Thesis, Montpellier, 2018. http://www.theses.fr/2018MONTG019/document.

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Les signaux d'avertissement que portent les proies toxiques (ou autrement défendues) offrent une opportunité unique de développer une vision intégrative de la diversification biologique. Ces signaux sont soumis à une forte sélection naturelle et sexuelle. D'une part, la stratégie d'échantillonnage utilisée par les prédateurs, caractérisée par l'apprentissage des signaux associés à la toxicité, protège les signaux en forte fréquence dans la communauté de proies. Cette sélection fréquence-dépendante positive favorise l'uniformité des phénotypes et la convergence de signaux entre espèces toxiques (mimétisme mutualiste dit "Müllerien") dans de nombreux taxons. D'autre part, les signaux d'avertissement sont utilisés comme critères de choix entre partenaires sexuels et sont donc soumis à de la sélection sexuelle avec des conséquences importantes pour l'émergence de l'isolement reproducteur et la spéciation. Paradoxalement, malgré une forte sélection naturelle favorisant la convergence, les signaux d'avertissement sont incroyablement diversifiés, à la fois au sein de la même espèce et entre espèces. Cette diversification morphologique est souvent associée à une importante diversification des espèces à l'échelle des clades. Dans cette thèse, j'apporte quelques explications à ce paradoxe et j'affine ainsi notre compréhension de l'effet de la sélection fréquence-dépendante positive et du mutualisme sur la diversification à l'échelle micro- et macro-évolutive. Premièrement, je montre que la stratégie d'échantillonnage des prédateurs peut favoriser la diversification des signaux d'avertissement malgré une sélection fréquence-dépendante positive. Deuxièmement, je dissèque les conditions permettant l'évolution d'un isolement reproducteur stable, nécessaire à la spéciation, dans certaines situations écologiques où les signaux mimétiques sont sous sélection naturelle et sexuelle. Troisièmement, je décris des effets indirect de la sélection fréquence-dépendante sur la diversification à l'échelle macro-évolutive par le biais de contraintes spatiales et de convergences écologiques secondaires
The display of warning signals by unpalatable (or otherwise defended) prey provides a wonderful opportunity for establishing an integrative view of biological diversification. Warning signals are known to be under strong natural and sexual selection. On the one hand, the sampling strategy of predators, characterized by a learned avoidance of signals associated with unpalatability, generates natural selection in favour of warning signals in high frequency in the prey community. Such positive frequency-dependent selection favours phenotypic uniformity and causes unpalatable species to converge on common warning signals (mutualistic "Müllerian" mimicry), as seen in a large panel of taxa. On the other hand, warning signals are used as a phenotypic cue for mate choice, generating sexual selection with important consequences for reproductive isolation and speciation. Paradoxically, despite powerful selection favouring phenotypic convergence, warning signals are fantastically diverse, both within and between species, and this morphological diversification is often associated with extensive species diversification at the clade level. In this thesis, I tackle this apparent paradox from the ground up and I thereby refine our understanding of the role of positive frequency-dependent selection and mutualistic interactions for evolutionary diversification at micro- and macroevolutionary scales. First, I show that the predator sampling strategy can favour the emergence of diversity of warning signals despite positive frequency-dependent selection. Second, I dissect the conditions allowing the evolution of strong and stable reproductive isolation, necessary for speciation to occur, in a number of ecological situations where warning signals are under natural and sexual selection. Third, I highlight important indirect effects of frequency-dependent selection on diversification at macro-evolutionary scale via spatial constraints and by-product ecological convergence

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32

Laroche, Julien. "Le processus d’interaction comme attracteur dans la coordination temporelle entre les personnes." Thesis, Université de Lorraine, 2013. http://www.theses.fr/2013LORR0365.

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Les interactions sociales sont souvent vues comme des échanges d’informations au cours desquels des états mentaux individuels se succèdent. Comment pouvons-nous dès lors être « ensemble » et partager un moment ? Dans cette thèse, nous optons pour une perspective centrée sur la coordination temporelle des comportements des personnes en interaction, en nous intéressant aux phénomènes de dynamiques collectives incarnées. Ces dynamiques coordonnent communément les comportements et émergent directement du processus d’interaction mutuel lui-même. Pour évaluer cette proposition, nous avons mené trois expériences. Notre méthodologie générale distinguait trois situations types : une situation de coordination individuelle, une situation pseudo-sociale dans laquelle le comportement doit être coordonné à celui d’une autre personne sans que la réciproque soit vraie, et enfin une situation dans laquelle l’interaction est mutuelle. Une première expérience nous a permis de montrer que la mutualité de l’interaction suffisait à induire une coordination entre les participants, dont les comportements étaient pris dans une dynamique collective qui leur échappait totalement. Ensuite, nous avons montré que la mutualité de l’interaction augmentait la stabilité des interactions rythmiques et provoquait un appariement de la complexité des comportements. Enfin, nous avons montré qu’en dépit d’un environnement commun très structuré, la mutualité de l’interaction induisait une organisation légèrement plus coordonnée du temps. Nous discutons ces résultats en regard de notre objet de recherche et de notre arrière-plan théorique
Social interactions are mostly seen as information exchanges during which individual mental states follow each other. How could we, accordingly, be « toghether » and share a moment ? In this thesis, we took a perspective focused on the temporal coordinations of interpersonal behaviors as they occur in the course of interactions, by studying the phenomenon of embodied collective dynamics. Such dynamics manifest coordinates behaviors mutually and emerge from the interaction process itself. To evaluate this hypothesis, we devised three experimental paradigms. We used a general methodology in which three typical situations are distinguished : the individual situation in which participants possess all the capacities to pursue the goal of the task, a pseudo-social situation in which behavior can be coordinated to the mouvement of an other, and a situation in which the interaction is mutual. In the first experiment, we showed the mutuality of interaction was sufficient to induce participants, whose behaviors were caught in collective dynamics unbeknownst to them. Then, we showed that mutuality of interaction was enhancing the stability of rhythmic interactions as well as the complexity matching between their behaviors. Finally, we showed that, in despite of a temporary structured environment, mutuality of interaction induced a slight more coordinated temporal organization of behaviors. We discuss these results in respect of our object of research and our theoretical background

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Sabagh, Leandro Talione. "Interações entre anuros, bromélias e a comunidade bromelícola associada em três unidades de conservação no Estado do Rio de Janeiro." Universidade do Estado do Rio de Janeiro, 2014. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=7283.

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Анотація:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro
Bromeliaceae é uma família vegetal com distribuição essencialmente neotropical frequentemente utilizada em estudos ecológicos devido às suas características de armazenar água livre, sustentar uma biota própria, apresentar tamanho relativamente reduzido e ter fácil replicabilidade por serem abundantes. Estas características conferem às bromélias o status de microcosmos natural e, dentro do ambiente bromelícola as espécies também interagem entre si. Anuros são habitantes comumente encontrados em bromélias sendo que algumas espécies têm estreita relação com estes vegetais ao ponto de passarem todo seu ciclo de vida associados a bromélias. Na presente tese foram estudados distintos organismos que habitam bromélias (e.g. ostracodas, protozoários, helmintos e artrópodes em geral) com ênfase em anuros do gênero Scinax (Hylidae). Foi realizado um experimento controlado em casa de vegetação para testar diferentes aspectos da relação entre anuros e bromélias usando como modelo S. perpusillus e Neoregelia sp. Foram também realizados estudos de campo em três unidades de conservação do estado do Rio de Janeiro, a saber: Monumento Natural do Morro da Urca e Pão-de-Açúcar; Parque Estadual da Serra da Tiririca; e Parque Nacional da Serra dos Órgãos onde, respectivamente, ocorrem os anuros S. perpusillus, S. littoreus e S. v-signatus. A tese está dividida em seis capítulos que abordam diferentes interações interespecíficas como predação, parasitismo, foresia e mutualismo.
Bromeliaceae is a plant family with neotropical distribution often used in ecological studies due to its characteristics of storing free water, maintains a self-biota, has a reduced size and have easy replicability. These features give the status to bromeliad of natural microcosm and, within the bromelicolous environment, the species also interact among themselves. Treefrogs are commonly found in bromeliads and some species is closely related to these plants spending all their life cycle associated with bromeliads. In this thesis different organisms inhabiting bromeliads were studied (e.g. ostracods, protozoa, helminths and arthropods in general) with emphasis on treefrogs of the genus Scinax (Hylidae). A controlled greenhouse experiment to test different aspects of the relationship between treefrogs and bromeliads was performed using as a model S. perpusillus and Neoregelia sp. We also performed field work in three protected areas in the state of Rio de Janeiro: Natural Monument of Morro da Urca and Sugar-Loaf, State Park of Serra da Tiririca, and National Park of Serra dos Órgãos where, respectively, occur the treefrogs S. perpusillus, S. littoreus, and S. v- signatus. The thesis is divided into six chapters that address different interspecific interactions such as predation, parasitism, phoresy, and mutualism.

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34

Huet, Guenahaël. "Mutualité et droit public." Lille 3 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb376059889.

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Wyatt, Gregory Alan Kenneth. "Coevolutionary adaptation in mutualisms." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:c3318211-a893-432e-a52e-35a6c60b76ce.

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Natural selection favours those individuals that respond best to novel features of their selective environment. For many, a critical challenge is responding to evolutionary change in mutualistic species. These responses create complex feedbacks, so only coevolutionary approaches are able to fully answer key questions about the maintenance or disruption of mutualistic behaviour, and explain the range of mechanisms that allow individuals to benefit from these associations. I first consider the hypothesis that economic models studying multiple classes of traders, where each trader seeks to optimise its own payoffs will yield insights into mutualistic systems. I show that individuals can be favoured to discriminate amongst potential partners based on the price for which they provide resources. Then, I show that market mechanisms can maintain cooperation and drive specialisation in mutualistic systems. I extend this market model to allow individuals to restrict a mutualistic partner's access to resources, and show that this strategy can stabilise cooperation and increase the fitness of both partners. I also explicitly incorporate relatedness in my market model. I show that high relatedness sometimes increases cooperativeness in members of a mutualistic species, but sometimes decreases cooperativeness as it narrow the scope for partner choice to maintain cooperation. Having studied market mechanisms, I consider indiscriminate costly help to members of another species. I discover that this trait can be favoured by natural selection and can be classified as either altruism between or altruism within species. Finally, I consider a framework for analysing coevolved phenotypic responses to a partner's cooperativeness, a challenging process to model. I demonstrate that this framework can yield firm predictions about behaviour whenever partners hold private information about their costs and benefits.

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Kaminski, Lucas Augusto. "Mirmecofilia em Parrahasius polibetes (Lepidoptera: Lycaenidae) = historia natural, custos, seleção de planta hospedeira e beneficios da co-correncia com hemipteros mirmecofilos." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/315760.

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Анотація:

Orientadores: Andre Victor Lucci Freitas, Paulo Sergio Moreira Carvalho de Oliveira
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: Formigas constituem um dos mais proeminentes grupos de organismos terrestres em termos de diversidade, abundância relativa e biomassa animal. Sua importância se deve principalmente ao comportamento eusocial aliado a complexos sistemas de comunicação. A vegetação de áreas tropicais é rica em fontes de alimentos renováveis que induzem a visitação freqüente de formigas às plantas. Sobre a vegetação, as formigas podem atuar como predadoras e acarretar um forte efeito sobre a comunidade de insetos herbívoros. A presença de formigas sobre plantas pode afetar insetos herbívoros basicamente de duas formas: (1) limitando sua ocorrência na folhagem através de interações antagônicas (ex. agressão, predação) ou (2) propiciando espaços livres de inimigos naturais para herbívoros mirmecófilos (que mantêm associações simbióticas com formigas). Em Lepidoptera, a mirmecofilia é amplamente difundida em apenas duas famílias de borboletas (Lycaenidae e Riodinidae). Devido a grande importância da interação com formigas para a morfologia e biologia destas borboletas, acredita-se que grande parte da história evolutiva desses organismos, incluindo eventos de diversificação seja explicada pela mirmecofilia. No entanto, a maior parte da informação sobre borboletas mirmecófilas é baseada no conhecido para espécies das faunas Paleártica, Oriental e Australiana. Enquanto que a rica fauna de borboletas mirmecófilas Neotropicais permanece praticamente desconhecida. Dentre as cerca de 1.200 espécies de Lycaenidae Neotropicais, Parrhasius polibetes (Stoll) (Lepidoptera: Lycaenidae) foi reportada recentemente co-ocorrendo espaço-temporalmente com hemípteros mirmecófilos em Schefflera vinosa (Araliaceae). Neste trabalho são descritos novos aspectos relacionados à morfologia e história natural dos estágios imaturos de P. polibetes, incluindo custos da mirmecofilia, seleção de planta hospedeira, e benefícios da co-ocorrência com hemípteros trofobiontes. O ciclo de desenvolvimento de ovo a adulto é de aproximadamente 36 dias, e o estágio larval compreende quatro instares. Os ovos são depositados exclusivamente em tecidos reprodutivos (botões florais) das plantas hospedeiras. As larvas são polífagas, sendo registradas em 28 espécies em 16 famílias de plantas. A maioria da plantas hospedeiras de P. polibetes (78.57%) apresenta algum tipo de fonte de alimento líquido que promovem a visitação por formigas, sejam nectários extraflorais e/ou hemípteros produtores de exudatos. A partir do terceiro instar, as larvas são atendidas facultativamente por mais de quinze espécies de formigas em três subfamílias (Formicinae, Myrmicinae e Ectatomminae), principalmente formigas do gênero Camponotus Mayr. Assim como em outros Lycaenidae, as interações entre larvas e formigas são mediadas principalmente por uma glândula especializada (dorsal nectar organ) no sétimo segmento abdominal que produz recompensas calóricas para as formigas. Nesse sentido, é esperado que a produção dessas secreções acarrete em custos para as larvas. Para P. polibetes, é demonstrado que as formigas Camponotus crassus e Camponotus melanoticus apresentam diferentes intensidades de atendimento. C. melanoticus atende mais intensamente as larvas que C. crassus em condições de laboratório. Por sua vez, essa diferença pode acarretar em diferentes custos para as larvas. Por exemplo, quando atendidas por C. melanoticus demoram mais tempo para empupar. No entanto, o peso pupal e o tamanho dos adultos não são afetados pela diferença de atendimento, sugerindo que P. polibetes possui mecanismos compensatórios para minimizar os custos da mirmecofilia. Esta é a primeira demonstração de que diferenças específicas de intensidade de atendimento podem afetar parâmetros de desempenho de um inseto trofobionte. Em campo, é demonstrado através de experimentos pareados que o padrão previamente detectado de co-ocorrência espacial entre larvas de P. polibetes e hemípteros mirmecófilos é provocado por dois fatores: 1) fêmeas são capazes de detectar e ovipositar em plantas com associação membracídeos-formigas; 2) larvas que se desenvolvem perto da associação membracídeos-formigas sobrevivem melhor que larvas em plantas sem associação. Tal efeito ocorre porque a presença da interação entre membracídeos e formigas reduz a abundância de potenciais inimigos naturais das larvas (aranhas e vespas parasitóides). Além disso, as larvas são mais facilmente encontradas e atendidas pelas formigas que são recrutadas pelos membracídeos. Ou seja, a presença da associação membracídeos-formigas gera um "espaço livre de inimigos" sobre a planta hospedeira, que é explorado por P. polibetes. Esses resultados mostram que o enfoque tradicional no estudo de mutualismo, baseado em pares de espécies, é inapropriado para entender as pressões seletivas operando em sistemas multitróficos
Abstract: Ants are one of the most prominent groups of terrestrial organisms in terms of diversity, relative abundance and biomass. Their importance is due primarily to eusocial behavior combined with complex communication systems. Tropical foliage is rich in renewable feeding sources that promote ant foraging. As some of the most important predators on plants, ants strongly affect the herbivorous insects. The presence of ants on foliages may affect herbivores by two ways: (1) decreasing herbivore individual numbers due to antagonistic interactions (e.g., aggressiveness, predation); (2) providing an enemy-free space for myrmecophilous herbivores (i.e. those living in close associations with ants). The symbiotic interaction between Lepidoptera and ants is widespread but only among two butterfly families (Lycaenidae and Riodinidae). Due to the great importance of myrmecophily for the morphology and biology of these butterflies, it is supposed that much of the evolutionary history of organisms, including diversification, would be explained by their interactions with ants. However, most of the knowledge about the evolutionary ecology of lycaenids is based on studies of well known Palaearctic, Oriental, and Australian species while little is known about the rich Neotropical fauna, which contains nearly 1,200 species. Larvae of Parrhasius polibetes (Stoll) (Lepidoptera: Lycaenidae) co-occur spatially and temporally with honeydew-producing hemipterans on the host plant Schefflera vinosa (Araliaceae). This study describes new aspects of morphology and natural history of immature stages of P. polibetes, including costs of myrmecophily, host plant selection, and benefits of co-occurrence with hemipteran trophobionts. The development cycle from egg to adult is approximately 36 days, and includes four larval instars. The eggs are laid exclusively on reproductive tissues (flower buds) of the host plants. The larvae are polyphagous, and have already been recorded on 28 plant species from 16 families. Most of the observed host plants of P. polibetes present some kind of liquid reward potentially used by ants (78.57%), either honeydew-producing hemipterans and/or extrafloral nectaries. From the third instar on, the larvae are facultatively tended by more than fifteen ants species in three subfamilies (Formicinae, Myrmicinae, and Ectatomminae), especially ants of the genus Camponotus Mayr. As in other Lycaenidae, interactions between larvae and ants are mediated by a specialized gland (dorsal nectar organ) on the seventh abdominal segment, which produces caloric liquid rewards for ants. Therefore it is expected that the production of these secretions entail costs for the larvae. For P. polibetes, it is shown that Camponotus crassus and Camponotus melanoticus ants differ in the intensity of tending levels to larvae, with C. melanoticus presenting increased tending rates compared to C. crassus. This difference can lead to different costs for the larvae. For instance when tended by C. melanoticus, larvae take longer to pupate. However, the pupal weight and size of adults are not affected by ant tending, suggesting that P. polibetes has compensatory mechanisms to minimize the costs of myrmecophily. This is the first demonstration that specific differences in ant tending may affect performance parameters in an insect trophobiont. In the field, experiments involving the manipulation of ant-treehopper associations on host plants demonstrated that the spatial co-occurrence between P. polibetes caterpillars and honeydew-producing hemipterans is caused by two factors: 1) females are able to detect ant-treehopper associations on foliage before oviposition, and lay eggs in their vicinity; 2) larvae that develop near ant-tended treehoppers survive better than larvae on plants without such association. This effect occurs because the presence of ant-treehopper associations reduces the abundance of potential natural enemies (spiders and parasitoid wasps) of the caterpillars. Moreover, the larvae are more easily found by prospective tending ants that are recruited to nearby honeydew-producing treehoppers. That is, the presence of ant-treehopper associations creates an "enemy-free space" on the host plant, which is exploited by P. polibetes. These results show that a traditional pairwise approach is obviously inappropriate to assess the selective pressures operating within such multi-species systems
Doutorado
Ecologia
Doutor em Ecologia

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González, Sergio Jansen. "Biologia larval de Pegoscapus tonduzi (Chalcidoidea: Agaonidae), polinizador de Ficus citrifolia (Moraceae)." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/59/59131/tde-05082009-112829/.

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A interação mutualística, espécie-especifica, vespas de figo-figueiras envolve dois processos antagonísticos, predação de sementes e polinização, realizadas por vespas da família Agaonidae. Sabe-se que a larva da vespa se alimenta de tecido da semente durante seu desenvolvimento, mas o processo pelo qual isto ocorre é pouco conhecido, não se sabendo até que ponto a larva depende do desenvolvimento da semente. Neste trabalho foi estudada a biologia larval de Pegoscapus tonduzi, polinizadora de Ficus citrifolia (Moraceae). O estudo foi realizado em plantas de F. citrifolia presentes no campus da Universidade de São Paulo em Ribeirão Preto/SP, durante o período de julho de 2007 a agosto de 2008. Para tal, quatro coortes de vespas foram estudas, nas quais cerca de cinco figos foram coletados em intervalos de dois dias, ao longo do ciclo de desenvolvimento larval. Os figos foram dissecados para observação das larvas e para a obtenção de ovários/galhas da planta para o preparo de lâminas histológicas. Os resultados mostraram que o processo de predação de sementes realizado pelas larvas de P. tonduzi é elaborado, com o desenvolvimento larval intimamente relacionado aos processos embriogênicos da planta. O desenvolvimento larval apresenta quatro instares, detectados pela mudança de tamanho e formadas larvas. A duração do ciclo de vida de P. tonduzi foi de 40 a 70 dias, aproximadamente, correlacionando-se negativamente com a temperatura ambiente no período. O ovo é depositado na região próxima à base do estilete, entre o nucelo e o tegumento interno do ovário da planta. Nessa fase, observase o surgimento do embrião vegetal, indicando que o ovário em que larva se desenvolve foi fertilizado. No segundo estádio larval, o inseto migra para a região micropilar e passa a se alimentar oralmente do endosperma da planta. Nesta fase, ainda, nota-se o desaparecimento do embrião vegetal, sugerindo que este é consumido pela larva da vespa. Os resultados sugerem a existência de um ajuste evolutivo fino entre inseto-planta, uma vez que o desenvolvimento da larva da vespa de figo parece depender da fertilização e conseqüente formação do endosperma.
The species-specific mutualistic interaction between fig trees and fig wasps engages two antagonist processes: seed predation and pollination, both achieved by wasps of the Agaonidae family. It is well known that fig wasp larvae feed on seed tissues for their development but the process itself is poorly known. Here is a study on the larval biology of Pegoscapus tonduzi, pollinator of Ficus citrifolia (Moraceae). The study was carried out between July 2007 and August 2008 at the Sao Paulo University campus in Ribeirao Preto, Sao Paulo State. Four cohorts of fig wasps were studied; for each cohort, about five figs were sampled each two days until complete larval cycle. Sampled figs were dissected for larvae observation and measurement, and flower ovaries/galls subsamples destined to histological study. Results showed that seed predation by fig wasps is a complex process, with larval development closely related to plant embryogenesis. Four larval instars were determined by changes on larva size and shape. Larval cycle extended from 40 to 70 days, showing a negative relation with environmental temperature. The egg is laid near the style insertion, between nucleus and inner integument of the flower ovary. Vegetal embryo was observed along with first larval instar, indicating that fertilization took place inside the ovary where larva develops. At second instar, the larva migrates to the micropilar region and begins to feed orally from endosperm. In this phase, the embryo disappears, suggesting that it is consumed by the larva. Our results suggest a fine tune evolutionary insect-plant adjustment, as fig wasp larvae seems to depend on ovary fertilization and endosperm development.

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Yardley, Lucy. "The experience of vertigo : a mutualist analysis." Thesis, University of Southampton, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316596.

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Dunn, Peter R. "Fiscal aspects of mutuality." Thesis, Queen Mary, University of London, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.538657.

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Huet, Guénhaël. "Mutualité et droit public." Paris 2, 1987. http://www.theses.fr/1987PA021041.

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Apres avoir situe la place de la mutualite au sein de l'economie sociale, l'objectif de notre etude est d'analyser les raisons et les fondements de la publicisation du droit mutualiste. L'intervention du juge administratif dans le fonctionnement des mutuelles, purs organismes de droit prive, est analysee dans son evolution historique qui permet de mettre en exergue la nature juridique de la mutualite. La premiere partie de la these retrace l'evolution juridique des institutions mutualistes depuis la revolution de 1789 jusqu'a la moitie du vingtieme siecle : les notions d'ordre public et d'utilite publique apparaissent, durant cette periode, comme les fondements successifs de la competence des juridictions administratives. La seconde partie est consacree a la reforme du code de la mutualite par la loi du 25 juillet 1985. Les principes traditionnels que sont la democratie, la liberte, l'independance et la solidarite permettent de distinguer la mutualite d'autres institutions analogues telles que les entreprises d'assurance ou la securite sociale. La specificite de la mutualite apparait egalement a travers l'action sociale qu'elle met en oeuvre et qui donne lieu, depuis de nombreuses annees, du fait de la concurrence des professions medicales, a un contentieux administratif important.

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Bastazini, Vinícius Augusto Galvão. "Integrando processos evolutivos e ecológicos no estudo de redes de interações." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2015. http://hdl.handle.net/10183/141862.

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Compreender como as espécies interagem e como a topologia de redes ecológicas influencia a dinâmica de populações e comunidades tem sido um dos principais objetivos de estudos ecológicos há mais de um século. Apesar desta longa tradição, o estudo de redes ecológicas tem aumentado drasticamente nas últimas duas décadas. No entanto, só recentemente ecólogos começaram a ir além da descrição de padrões topológicos e passaram a integrar outros dados biológicos importantes, como características funcionais e filogenia. Esta tese teve principalmente dois objetivos: i) desenvolver novas abordagens analíticas capazes de integrar informações funcionais e filogenéticas, a fim de descrever padrões estruturais em redes ecológicas, e ii) compreender a influência de dinâmicas eco-evolutivas na robustez de redes mutualísticas. No Capítulo I, desenvolvi uma abordagem analítica integradora para particionar os efeitos da filogenia e de características funcionais sobre a estrutura de redes de interação biótica. O método combina Teoria de Conjuntos Difusos e correlação matricial. Eu também desenvolvi um estudo de simulação para testar a acurácia da metodologia proposta em termos de Erro Tipo I. As simulações demonstram que o método é acurado, ou seja, rejeita incorretamente uma hipótese nula verdadeira em ~ 5% dos casos. No Capítulo II, investiguei como diferentes cenários de extinção afetam a robustez de uma rede de dispersão de sementes do sul do Brasil, incluindo cenários onde as espécies são eliminadas com base em sua distinção evolutiva e funcional. Os resultados indicam que a perda de espécies generalistas e diversidade funcional faz com que rede seja mais propensa a colapsar. No Capítulo III, desenvolvi uma investigação teórica sobre a influencia de diferentes modos de evolução de atributos sobre a robustez de redes mutualísticas que estão sofrendo um ataque funcional. Os resultados mostram que, apesar da pequena faixa de variação na robustez das redes, o modo de evolução dos atributos, e a interação entre modos de evolução de cada conjunto de espécies que interagem, influenciam a robustez de redes ecológicas, especialmente em casos extremos, onde os atributos das espécies apresentam sinal filogenético muito baixo ou muito forte.
Understanding how species interact and how the topology of ecological networks influences the dynamics of populations and communities has been mindboggling ecologists for over a century now. Despite this long tradition, the study of complex ecological networks has increased dramatically in the past two decades. Nonetheless, only recently ecologists have started to move beyond the description of topological patterns and started to integrate other important biological data, such as functional traits and phylogenies. Therefore, the aim of this dissertation was mainly two-fold: develop new analytical approaches capable to integrate functional and phylogenetic information in order to describe structural patterns in ecological networks, and to understand the effects of ecoevolutionary dynamics on network robustness. In Chapter I, I developed a new and integrative analytical framework to partition the effects of phylogenies and functional traits on the structure of ecological networks. The method combines fuzzy set theory and matrix correlation. I also developed a simulation study to test the accuracy of the framework I proposed. My simulation study demonstrates that the method is accurate, i.e., incorrectly rejecting a true null hypothesis in ~ 5%. In Chapter II, I investigated how different extinction scenarios affect the robustness of a seed dispersal network, from southern Brazil, including scenarios where species are eliminated based on their evolutionary and functional distinctiveness. The results indicate that loss of generalist species and functional diversity makes the system more likely to collapse. In Chapter III, I developed a theoretical investigation of the role of distinct trait evolution modes on the robustness of mutualistic networks undergoing functional trait extinctions. My results show that, despite the small range of variation in network robustness, the mode of trait evolution alone and the interaction between modes of evolution of each set of interacting species matter for network robustness, especially in extreme cases, where species traits present either very low or very strong phylogenetic signal.

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MARTINS, Joanny Kelly Silva dos Santos. "Interações ecológicas associadas a Ipomoea carnea subs. fistulosa (Martius e Choise) (convolvulaceae) em uma área de caatinga no Nordeste do Brasil." Universidade Federal Rural de Pernambuco, 2015. http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/5437.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
The objective of this study was to survey the richness and abundance of pollinators, herbivores, ants and other predators associated to Ipomoea carnea subs. fistulosa, addition to assessing the indirect effects of florivory and the influence of patrolling ants associated with extrafloral nectaries on pollinators. The study was conducted durig eight months (August/2014 – March/2015) at the Fazenda Tamanduá, municipality of Santa Terezinha, Paraíba state, Brazil. It was quantified the number of pollinator visits in flowers with and without patrolling ants and flowers with simulated florivory. The number of herbivores per inflorescence and the occurrence of florivory were recorded in an experiment conducted from 5 am to 5 pm. Arthropods were collected monthly to record the richness and abundance. The temporal variation of florivory and production of buds, flowers and fruits were recorded monthly. The results of the effect of the damage and the presence of floral ants showed that both cause a decrease in the total number of visits. This can be explained by the fact that the floral damage was the loss of important floral attributes. Additionally, bees can evaluate the pattern of flower symmetry distance and detect predators corroborating the hypothesis that predators such as ants, remove pollinators of plant-pollinator systems. These effects may be considered risky for Ipomoea carnea subs. fistulosa, since it is a self-incompatible species and depends on the activity of pollinators for its fertilization. The composition of the arthropod fauna associated with plant species under study was represented by five groups: Araneae, Coleoptera, Hymenoptera, Diptera and Hemiptera. The highest abundance of herbivores occurred in months with low rainfall. The florivory rates were high, and more severe in the dry season. The number of ants associated to extrafloral nectaries increased directly with the abundance of herbivores over months. The multitrophic system studied showed complex, featuring a high richness of associated arthropods and various guilds among the trophic levels. During the dry season in the caatinga, Ipomoea carnea subs. fistulosa is one of the few species that persist with leaves and flowers, this enables the populations of I. carnea constitute major indicator spots resources for present herbivores. This may have been one of the main causes for the abundance of herbivores and floral herbivory rate was higher in the months with less precipitation. Overall the data suggest that abundance of herbivores was related to the quality and availability of plant resources, reflecting on other trophic levels as in a bottom-up model of trophic cascade.
O objetivo deste trabalho foi realizar um levantamento da riqueza e abundância dos polinizadores, herbívoros, formigas e predadores de insetos associados a Ipomoea carnea subs. fistulosa, bem como avaliar os efeitos indiretos da florivoria e a influência do patrulhamento de formigas associadas aos nectários extraflorais sobre os polinizadores. Este trabalho foi realizado em oito meses de coleta (agosto de 2014 a março de 2015) na Fazenda Tamanduá, no município de Santa Terezinha, PB. Foi quantificado o numero de visitas de polinizadores em flores com e sem patrulhamento de formigas e em flores com florivoria simulada. O número de herbívoros por inflorescência e a ocorrência de florivoria foi registrado em um experimento realizado das 5h às 17h. Os artrópodes foram coletados mensalmente para registro da riqueza e abundância. E a variação temporal da florivoria e produção de botões, flores e frutos foi registrada mensalmente. Os resultados do efeito do dano floral e presença de formigas mostraram que ambos provocam decréscimo no número de visitas totais. Isso pode ser justificado pelo fato de que o dano floral consistiu na perda de atributos florais importantes. Adicionalmente abelhas podem avaliar o padrão de simetria da flor à distância e detectar predadores corroborando com a hipótese de que predadores, tal como formigas, retiram polinizadores dos sistemas planta-polinizador. Estes efeitos para Ipomoea carnea subs. fistulosa podem ser considerados de risco, uma vez que é um espécie autoincompatível e depende da atividade dos polinizadores para que a sua fecundação ocorra. A composição da fauna de artrópodes associados a espécie vegetal em estudo foi representada por cinco grupos: Araneae, Coleoptera, Hymenoptera, Diptera e Hemiptera. O sistema multitrófico estudado se mostrou complexo, apresentando uma grande riqueza de artrópodes associados e variadas guildas dentre os níveis tróficos. Durante a estação seca na caatinga Ipomoea carnea subs. fistulosa, é uma das poucas espécies que persistem com folhas e flores, fato que faz com que as populações de I. carnea constituam grandes manchas indicadoras de recursos para os herbívoros presentes. Esta pode ter sido uma das principais causas para que a abundância de herbívoros e taxa de herbivoria floral tenha sido mais alta nos meses com menor precipitação. De maneira geral os dados sugerem que abundância de herbívoros respondeu a qualidade e disponibilidade dos recursos vegetais, refletindo nos demais níveis tróficos como em um modelo bottom-up de cascata trófica.

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Costa, Neto Diôgo Januário da. "Leveduras vetorizadas por abelhas sem ferrão em áreas de cerrado no estado do Tocantins, Brasil." Universidade Federal do Tocantins, 2017. http://hdl.handle.net/11612/415.

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Há evidência de interação mutualista entre leveduras e abelhas sem ferrão, em que estas são vetores de leveduras que servem de alimento e modificam produtos do ninho das abelhas. Vários estudos registraram a ocorrência de espécies dos gêneros Candida e Starmerella associadas ao ninho de diferentes meliponíneos. Nesse estudo foram identificadas as espécies de leveduras vetorizadas por Frieseomellita varia, Scaptorigona polysticta, Sacaptorigona postica, Tetragonisca angustula angustula, Melipona compressipes manaoensis e Melipona scutellaris em regiões e meliponários no Cerrado tocantinense, e feita uma análise das características funcionais das leveduras vetorizadas pela abelha Scaptorigona postica. Amostragens foram realizadas entre os anos de 2006 a 2015 em sistemas de meliponicultura localizados em quatro municípios do Estado do Tocantins, região norte do Brasil, sendo espécimes de abelhas campeiras capturadas na entrada dos ninhos com sacos plásticos e postas para caminhar em placas contendo meio YMA. Os isolados foram identificados por métodos moleculares, realizando-se extração de DNA, agrupamento por reação em cadeia da polimerase (PCR) utilizando o primer EI-1 e sequenciamento do domínio D1/D2 do gene 26S rDNA utilizando os primers NL-1 e NL-4. As características funcionais das leveduras vetorizadas por S. postica foram mensuradas por testes fisiológicos e bioquímicos para as habilidades de assimilar oito compostos de carbono e quatro álcoois, fermentação de glicose, crescimento em meio contendo ácido acético, meio osmofílico e nas temperaturas 37°C e 40°C. Entre os diferentes meliponineos, foram identificados 62 espécies de leveduras, classificadas em 18 gêneros do filo Ascomycota e seis do filo Basidiomycota, sendo observado uma maior frequência das espécies Torulaspora delbrueckii, Candida apicola, Pichia membranifaciens, Pichia kluyveri e Starmerella meliponinorum, representando 41% do total de isolados. Destas, C. apicola e S. meliponinorum são frequentes em meliponineos, enquanto que as outras são típicas de substratos açucarados, mostrando que as abelhas vetorizam leveduras de seus ambientes de coleta de polén e néctar. Diferenças na composição de espécies ocorreram entre Meliponini e Trigonini, mostrando estratégias diferentes de visitação nos substratos contendo leveduras. Ainda, cada abelha vetoriza uma comunidade típica de leveduras, o que pode indicar hábitos seletivos e diferenciais de coleta. A análise das características funcionais de 52 linhagens isoladas de S. postica revelou que em grande parte das leveduras assimilam os carboidratos galactose, maltose, celobiose e trealose, em quanto que o número de leveduras que assimilam sacarose, amido, melibiose e xilose foi menor. O etanol foi assimilado por 36,53% das leveduras, mas acetona, metanol e isopropanol foram pouco frequentes. Grande parte das leveduras foi fermentadora, osmofilica e resistente ao ácido acético, mostrando adaptação a altas concentrações de açucares e ambiente fermentativo.
There are evidences for a mutualistic interaction between yeasts and stingless bees, in which bees vector yeasts that serve as food item or modify the products of the nest. Various studies report the occurrence of species of the generea Candida e Starmerella associated with nests of different meliponini. In this study we identified the yeast species vectored by Frieseomellita varia, Scaptorigona polysticta, Sacaptorigona postica, Tetragonisca angustula angustula, Melipona compressipes manaoensis and Melipona scutellaris in areas of Cerrado, and we made a funtional analysis of the yeasts associated with Scaptorigona postica. Sampling was done between the years 2006 and 2015 in Tocantins State, Northern Brasil, and the collector bees were captured iin the nest entrance with sterile bags and put to walk on agar platescontaining YMA. Yeast isolates were identified by molecular methods using DNA extraction, PCR fingerprinting with primer EI-1 and sequencing of D1/D2 region of the gene 26S rDNA uing primers NL-1 and NL-4 of representative strains. Functional characters were tested as carbohydrate assimilation, osmotolerance and acid tolerance, and resistance to 37°C and 40°C for yeasts isolated from Scaptorigona postica. Among all stingless bees, 62 yeast species belonging to 18 genera of Ascomycota and six Basidiomycota were identified, with a higher frequency ofTorulaspora delbrueckii, Candida apicola, Pichia membranifaciens, Pichia kluyveri and Starmerella meliponinorum that represented 41% of the strains. Among these, C. apicola and S. meliponinorum are frequent in stingless bees, and the others are commonly isolated from sugary substrates, indicating that the bees vector yeasts from the enviroments where they collect nectar and pollen. Significant differences in the yeast composition occur between Meliponini and trigonini, indicating different strategies of visitation in the substrates colonized by yeasts. Also each bee species carries different yeast communities, indicating a selective and different collecting habit. Functional characters of 52 yeasts isolated from S. postica revealed that most assimilate simple sugars galactose, maltose, celobiose, and trealose, bu only ¼ of them assimilate sucrose and xylosis. Assimilation of starch and mellibiose was uncommon. Ethanol was assimilated by 36,53% of the yeasts but acetona, metanol and isopropanol were less frequently assimilated. Most yeasts was fermentative, osmophillic and resistant to acetic acid which indicates an adaptation to high sugar concentrations and the fermentative environment.

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Golfeto, Camilla Calemi. "Estudos de poligalacturonases do fungo mutualista Leucoagaricus gongylophorus." Universidade Federal de São Carlos, 2014. https://repositorio.ufscar.br/handle/ufscar/6317.

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Universidade Federal de Minas Gerais
Polygalacturonases (PGases) are enzymes which hydrolyze glycosidic linkages - 1,4 between pectic acid residues, and are produced by plants, fungi, bacteria and yeasts. The fungus L. gongylophorus, Atta sexdens ant mutualist, secretes enzymes with PGase activity. The project was developed in two approaches: study with recombinant and native PGase. The activity on polygalacturonic acid of native PGase in fungus culture medium was determined, and its purification from crude extract was performed by (NH4)2SO4 precipitation and molecular exclusion chromatography. PGase kinetic parameters (Vmax and KM), optimal pH and temperature were determined, and the enzyme was immobilized on magnetic particles, proved to be a good method to future work inhibitors search. A cDNA library was constructed from total RNA obtained from L. gongylophorus culture in induction medium. 816 clones from the library were sequenced, allowing the identification of enzymes sequences involved in the plant cell wall degradation, some already in cloning and expression in our laboratory. Using a deposited L. gongylophorus PGase (PGase-Lg) sequence (GenBank: ADV30326.1), primers were designed to amplify the PGase-Lg gene, with cleavage sites for EcoRI, HindIII and NotI enzymes, respecting the pETSUMO (for E. coli expression) and pPICZA (for P.pastoris expression) reading phase vectors. From the cDNA, the PGase-Lg ORF encoding was amplified by PCR and cloned in both vectors. The clones were confirmed by plasmid DNA extraction and PCR. E. coli expression experiments of pETSUMO-PGase-Lg construction showed a great expression of His.tag-SUMO.tag-Lg-PGase fusion protein in the insoluble form and many expression and solubility assays were inefficient in solubility of expressed fusion protein. The protein refolding was performed and this was obtained in soluble form but lacks PGase activity, showing that folding may not have been correctly or E. coli fusion protein expressed does not undergo post-translational modifications to have enzymatic activity. The rPGase-Lg expressed in P. pastoris showed PGase activity on polygalacturonic acid and electrophoresis analysis suggest more than one enzyme expression, with different glycosylation content.
Poligalacturonases (PGases) são enzimas que hidrolisam ligações glicosídicas -1,4 entre resíduos de ácido péctico, e são produzidas por plantas, fungos, bactérias e leveduras. O fungo L. gongylophorus mutualista da formiga Atta sexdens, secreta enzimas com atividade PGase. O projeto foi desenvolvido sob duas abordagens: estudo com a PGase nativa e recombinante. A atividade sobre ácido poligalacturônico da PGase nativa foi determinada no extrato bruto do fungo, e sua purificação foi feita por precipitação com (NH4)2SO4 e cromatografia de exclusão molecular. Temperatura e pH ótimos e parâmetros cinéticos Vmax e KM foram determinados, e a PGase foi imobilizada em partículas magnéticas, mostrando ser um bom método na busca de inibidores. Construiu-se uma biblioteca de cDNA a partir de RNA total obtido de cultura de L. gongylophorus em meio indutor. Foram sequenciados 816 clones da biblioteca, permitindo identificar sequências de enzimas envolvidas na degradação da parede celular vegetal, algumas em fase de clonagem e expressão em nosso laboratório. Utilizando uma sequência de PGase de L. gongylophorus (PGase-Lg) depositada (GenBank: ADV30326.1), foram desenhados oligonucleotídeos para a amplificação do gene da PGase-Lg, com sítios de clivagens das enzimas EcoRI, HindIII e NotI, respeitando a fase de leitura dos vetores pETSUMO (para expressão em E.coli) e pPICZA (para expressão em P.pastoris). A partir do cDNA, a ORF codificante da PGase-Lg foi amplificada por PCR e clonada nos dois vetores. Os clones foram confirmados por extração de DNA plasmidial e PCR. Experimentos de expressão em E. coli da construção pETSUMO-PGase-Lg apresentaram grande expressão da proteína em fusão His.tag-SUMO.tag-PGase-Lg na forma insolúvel, e vários ensaios de expressão e solubilidade se mostraram ineficientes na solubilidade da proteína em fusão expressa. Realizou-se o refolding da proteína e esta foi obtida na forma solúvel, porém sem atividade, mostrando que o enovelamento pode não ter ocorrido corretamente ou que a proteína em fusão expressa pela E. coli não sofre as modificações pós-traducionais necessárias. A rPGase-Lg expressa em P. pastoris apresentou atividade PGase em ácido poligalacturônico, e análise em eletroforese sugere a expressão de mais de uma proteína, com conteúdos diferentes de glicosilação.

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Decocq, Frédérique. "Psychologie phénoménologique de la réciprocité : dynamique de l'être-ensemble pour la performation de l'agressivité humaine et sportive." Thesis, Montpellier 3, 2015. http://www.theses.fr/2015MON30001/document.

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La division sociale actuelle pousse à réfléchir sur la capacité d'un individu à vivre avec autrui dans un monde commun pacifié. Nous soutenons qu'un processus pré-psychique est à l'œuvre au sein de la relation intersubjective : l'être-soi et l'être-ensemble se créent par la dynamique de reconnaissance mutuelle des consciences (le phénomène de réciprocité). La « figure de référence » en est l'initiateur. Cette thèse a été mise à l'épreuve dans le champ du sport. La première série d'études a montré que le don de soi authentique de la figure de référence, l'être-auprès-de, préserve l'être-ensemble. Une deuxième série d'études a montré que la conscience d'intersubjectivité de la figure de référence permet d'amorcer le mouvement de réciprocité. Enfin, une recherche-action dans un atelier à médiation sportive a montré comment la lutte pour la reconnaissance, si la figure de référence est « atmosphériquement bonne » et reconnue comme telle, performe l'agressivité primitive d'un jeune délinquant vers la mutualité des consciences, par la création d'une unité soi-monde. L'ensemble des résultats permet de conclure que le phénomène de la réciprocité dégage en même temps un phénomène corporel passif (la réception) et un phénomène corporel actif (le don et le par-don)
The present social division urges to think about humans's competence to live side by side on a peace common world. We assert that an intersubjective psychic process that would operate in intersubjectivity's relationship: human being and being together are created by a dynamics of mutual recognition of consciousnesses (reciprocity phenomenon). “Reference figure» initiate that. This thesis was put to the test in the field of sport. The first study showed that an authentic self-sacrifice by the reference figure, being-next-to, keeps safe from being-together. A second study showed that a consciousness of intersubjectivity of the reference figure allows a start of the reciprocity movement. Finally, a research-action into sportive-mediated workshop showed how a fight for recognition, if the reference figure is “atmospherically good” and is recognized as such, shows how the primitive aggressiveness of a young delinquent perform towards a mutuality of consciousnesses by a oneself-common world ‘s unity creation. All the results allow to conclude that the reciprocity phenomenon releases a passive physical phenomenon (reception) together with an active physical phenomenon (giving, for-giveness)

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46

Coimbra, Klein Cecilia. "Bioinformatic study of the metabolic dialog between a non-pathogenic trypanosomatid and its endosymbiont with evolutionary and functional goals." Phd thesis, Université Claude Bernard - Lyon I, 2013. http://tel.archives-ouvertes.fr/tel-01050338.

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In this thesis, we presented three main types of analyses of metabolism, most of which involved symbiosis: metabolic dialogue between a trypanosomatid and its symbiont, comparative analyses of metabolic networks and exploration of metabolomics data. All of them were essentially based on genomics data where metabolic capabilities were predicted from the annotated genes of the target organism, and were further refined with other types of data depending on the aim and scope of each investigation. The metabolic dialogue between a trypanosomatid and its symbiont was explored with functional and evolutionary goals which included analysing the classically defined pathways for the synthesis of essential amino acids and vitamins, exploring the genome-scale metabolic networks and searching for potential horizontal gene transfers from bacteria to the trypanosomatids. The comparative analyses performed focused on the common metabolic capabilities of different lifestyle groups of bacteria and we proposed a method to automatically establish the common and the group-specific activities. The application of our method on metabolic stories enumeration to the yeast response to cadmium exposure was a validation of this approach on a well-studied biological response to stress. We showed that the method captured well the underlying knowledge as it extracted stories allowing for further interpretations of the metabolomics data mapped into the genome-scale metabolic model of yeast

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Sacramento, Cleidivaldo de Almeida. "Mundos do trabalho no Recôncavo Sul: cotidiano, trabalhadores, costumes, conflitos e solidariedades, 1879 – 1910." reponame:Repositório Institucional da UFBA, 2007. http://www.repositorio.ufba.br/ri/handle/ri/11116.

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O objetivo deste trabalho é analisar as relações e práticas de trabalho existentes no Recôncavo Sul da Bahia, durante os anos de 1879 a 1910. O principal recorte desta análise é o cotidiano de específicas categorias de trabalhadores que se organizaram em torno de serviços e atividades produtivas, algumas delas consideradas primazes na formação da economia baiana no final do século XIX e início do século XX. Em um segundo momento, são analisados os conflitos desses trabalhadores e estratégias na busca de direitos e garantias, demonstrando o “amadurecimento” de suas experiências e as divergências existentes nos “mundos do trabalho”. Tentou-se seguir, aqui, a proposta da Historiografia Social do Trabalho, abordando aspectos da história regional, e, privilegiando o estudo das ações coletivas em um universo de trabalhos marcado por conflitos.
Salvador

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Costa, Priscila Canesqui da. "COMUNIDADE DE INSETOS ASSOCIADOS AOS SICÔNIOS DE TRÊS ESPÉCIES DE FIGUEIRAS NO PANTANAL SUL MATOGROSSENSE." Universidade Federal de Santa Maria, 2010. http://repositorio.ufsm.br/handle/1/5271.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Syconia of fig trees present a diverse interaction with different groups of organisms. In this study we characterized insect community associated with three fig species in the region of Miranda/Abobral, Pantanal Sul matogrossense, obtaining data about species richness and abundance of these insects. We verified the specificity of these insects in regard to hosts and tested whether the size and number of flowers in the syconium determine species richness and abundance of insects in the syconia. We found 31 morpho-species of insects in the syconia of the three hosts. Syconia of Ficus obtusifolia had the highest richness (N = 18) and highest number of species co-occurring in the same syconia. Seven insect species were found sharing hosts. Mean abundance and species richness of insects in syconia of F. obtusifolia were significantly higher than in F. pertusa and F. luschnathiana what was related to the higher volume and number of flowers in the syconia of this fig tree. Our data may help in understanding the diversity and distribution of the insects associated with syconia of fig trees in the neotropical region. Papers that study Ficus insects associated system are important to show how these interactions occur in distinct fig trees and in different localities.
Sicônios de figueiras apresentam uma diversificada interação com diferentes grupos de organismos. Neste estudo, nós caracterizamos a comunidade de insetos associados a três espécies de figueiras na região do Miranda/Abobral, Pantanal Sul matogrossense, obtendo dados sobre a riqueza de espécies e a abundância destes insetos. Verificamos a especificidade destes insetos em relação aos hospedeiros e testamos se o volume e o número de flores dentro do sicônio determinam a riqueza de espécies e a abundância de insetos dentro dos sicônios. Foram encontradas 31 morfo-espécies de insetos nos sicônios das três espécies de figueiras analisadas. Sicônios de F. obtusifolia apresentaram a maior riqueza de espécies (S = 18) e maior número de espécies coocorrendo no mesmo sicônio. Sete espécies de insetos compartilharam hospedeiros. A média da abundância e da riqueza de espécies de insetos co-ocorrendo em sicônios de F. obtusifolia foi significativamente maior do que em F. pertusa e F. luschnathiana, fato que está ligado ao maior volume e número de flores nos sicônios desta figueira. Nossos resultados podem auxiliar no entendimento da diversidade e distribuição de insetos associados a sicônios de figueiras na região Neotropical. Trabalhos que abordam o sistema Ficus insetos associados são importantes para responder como estas interações acontecem em espécies de figueiras distintas e em diferentes localidades.

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Izquierdo, Juliana Verónica. "O papel de associação entre formigas e nectários extranupciais sobre o êxito reprodutivo de Tocoyena formosa (Rubiaceae)." Botucatu, 2017. http://hdl.handle.net/11449/150004.

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Orientador: Felipe Wanderley Amorim
Resumo: As plantas oferecem recurso alimentar a muitas espécies animais através de diferentes estruturas. Dentre tais estruturas estão os nectários, que são glândulas multicelulares especializadas na produção e secreção de néctar. Estes nectários podem ocorrer tanto em partes reprodutivas como vegetativas, e podem ser florais ou extraflorais. Entretanto, também podem ser classificados quanto a sua função em relação com a polinização, sendo do tipo nupcial (quando sua função está relacionada à polinização) ou extranupcial (quando sua função está relacionada à defesa). Tocoyena formosa (Rubiaceae) é uma espécie comum do Cerrado, cujos nectários extraflorais são visitados por formigas. Entretanto, T. formosa tem um único nectário que desempenha funções multivalentes, podendo ser tanto nupcial, quanto extranupcial. Adicionalmente, a espécie também atrai formigas aos botões no início da fase de desenvolvimento cujas corolas são abortadas. Neste contexto, para melhor compreender a interação entre T. formosa e formigas, este trabalho teve como objetivos: a) caracterizar as estruturas das distintas fases do nectário da espécie e a composição química de seus açúcares; b) determinar se existe mudança estrutural e/ou química que seja correspondente com o papel ecológico de cada estágio; c) analisar a dinâmica de secreção do néctar em cada um dos estágios de atividade do nectário; e d) quantificar o investimento da planta no recurso para a atração de formigas e o efeito destas no êxito reproduti... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Plants offer food resources to many animal species through different structures. Among such structures are the nectaries, which are multicellular glands specialized in nectar production and secretion. Nectaries can occur in both reproductive and vegetative parts, and depending on the location can be regarded as floral or extra-floral. However, they can also be classified according to their function in relation to pollination, being nuptial (when their function is related to pollination) or extranupcial (when their function is related to the defense). Tocoyena formosa (Rubiaceae) is a common species of the Cerrado vegetation, whose extrafloral nectaries are visited by ants. However, T. formosa has a single nectary that performs multivalent functions, which can be both nuptial and extranuptial. In addition, the species also attracts ants to the flower buds at the beginning of the development, whose corollas are prematurely aborted. In this context, to better understand the interaction between T. formosa and ants, the main goals of this study were: a) to characterize the nectary structure as well as the sugar chemical composition during the distinct stages of the organ; b) assess whether nectary structure and nectar sugar composition present changes which correspond to the ecological function of each stage of the nectary; c) analyze nectar secretion dynamics of each phase of the nectary; and d) quantify plant investment in the attraction of ants and the effectivity of ants in pl... (Complete abstract click electronic access below)
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Junior, Paulo Sérgio Mendes Pacheco. "Ecologia comportamental e de interações entre Pseudomyrmex concolor Smith (Hymenoptera, Formicidae, Pseudomyrmecinae) e sua planta hospedeira Tachigali myrmecophila Ducke (Fabaceae: Caesalpinioideae) na Amazônia amapaense." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/59/59131/tde-03012017-104546/.

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Na região centro-oriental da Amazônia, a formiga Pseudomyrmex concolor forma associação mutualista com plantas da espécie Tachigali myrmecophila, onde a formiga estabelece sua colônia nas domácias dessa Fabaceae. Apesar dessa planta não disponibilizar diretamente nenhum recurso alimentar, as formigas funcionam como agentes anti-herbivoria. Esse fenômeno torna o modelo Pseudomyrmex-Tachigali apropriado para testar hipóteses sobre relações ecológicas mutualistas formiga-planta. Espécies que vivem juntas tem como característica o desenvolvimento de estratégias defensivas para manutenção do valor adaptativo de ambas. Esta tese trata da ecologia comportamental e de interações no sistema Pseudomyrmex-Tachigali com o objetivo principal de descrever padrões e explicar processos ecológicos que contribuam para o esclarecimento desse fenômeno. O modelo mutualista utilizado é distribuído em sub-bosques de Florestas de Terra Firme amazônica na Área de Proteção Ambiental do Rio Curiaú, Amapá. Esta tese foi organizada em quatro capítulos que se propõem a responder perguntas, a partir de uma abordagem experimental e observacional, sobre história natural, morfologia, ecologia e comportamento animal dessa relação ecológica. O capítulo 1 teve como objetivo caracterizar o ninho e descrever a estrutura e composição colonial de P. concolor, demonstrando que características como tamanho da planta e espaço da domácia são fatores limitantes para o crescimento colonial. Além disso, evidenciou-se que operárias de P. concolor patrulham e investigam T. myrmecophila diuturnamente durante a estação chuvosa e estação seca amazônico. No capítulo 2 foi corroborada a hipótese de que P. concolor funciona como defesa biótica induzida, e que essas formigas investem mais esforços na defesa de partes mais valiosas para sua planta hospedeira. O capítulo 3 demonstrou que operárias de P. concolor apresentam variação espaço-temporal em T. myrmecophila associada a divisão de trabalho na defesa da colônia. No quarto e último capítulo, evidenciou-se que operárias de P. concolor são eficazes em reconhecer companheiras de ninho e discriminar intrusos, baseadas em sinais químicos, através de comportamentos agressivos. Os quatro capítulos em conjunto retratam a história natural de um mutualismo bem-sucedido entre uma formiga e uma planta mirmecófita na Amazônia brasileira.
In the central-eastern region of the Amazon, the ant Pseudomyrmex concolor (Pseudomyrmecinae) establishes obligatory mutualistic relationship with the plant Tachigali myrmecophila (Caesalpinaceae), where the ants nest inside the domatia. These plants dont directly provide any food resource, even though the ants act as anti-herbivory agents. This phenomenon makes Pseudomyrmex-Tachigali an appropriate model to test hypotheses about obligatory mutualistic ecological relationships. Species living together are characterized by the development of defensive strategies for maintaining the fitness of both organisms related. This thesis addresses the behavioral ecology and interactions of the Pseudomyrmex-Tachigali system, with the major aim to describe patterns and explain ecological processes that contribute to the elucidation of this issue. The mutualistic model analysed is distributed in the Terra Firme Amazonon Forest environments of River Curiaú Reserve, Amapá-Brazil. We organized the study into four chapters that intend to answer questions, from an experimental and observational approach, about natural history, morphology, ecology and animal behavior of this ecological relationship. In chapter 1, we characterized the nest as well as we described the structure and colonial composition of P. concolor. We verified that features such as size of plant and domatia space are factors that limit the colonial growth in P. concolor. In addition, we showed that workers patrol and investigate T. myrmecophila during day and night throughout the winter and summer Amazonian. In Chapter 2, we corroborate the hypothesis that P. concolor works as induced biotic defense and they invest more efforts toward defend the most valuable parts to their host plant. In Chapter 3, we showed that workers of P. concolor have spatio-temporal variation in T. myrmecophila plants associated with division of labor related to defense of the colony. In the fourth and final chapter, we found that P. concolor are effective to recognize nestmates and discriminate intruders through aggressive behaviors, based upon chemical cues. The four chapters together portray the natural history of the successful mutualism between an ant and their myrmecophytic plant in the Brazilian Amazon.

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