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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Impacts of global changes on biological invasions and interspecific hybridization within the Tetramorium caespitum ant species complex / Impacts des changements globaux sur les invasions biologiques et l'hybridation interspécifique au sein du complexe d'espèces de fourmis Tetramorium caespitum

Cordonnier, Marion 26 November 2018 (has links)
Changement climatique, urbanisation, invasions biologiques et hybridation interspécifique constituent des menaces majeures pour la biodiversité. L'objectif de cette thèse a été d'évaluer leurs effets interactifs sur les fourmis du genre Tetramorium de la vallée du Rhône, France. Près de 2000 colonies de 5 espèces de Tetramorium ont été étudiées. Les résultats démontrent que le climat et l'urbanisation limitent leurs aires de répartition et que l'urbanisation impacte leurs distributions simultanément à plusieurs échelles spatiales. Les probabilités d'occurrence de T. immigrans dépendent de l'interaction entre facteurs climatiques et urbains. Quatre populations génétiques de T. immigrans résultent de plusieurs introductions de sources externes, ce qui signifie que cette espèce n’est pas indigène dans les zones urbaines du nord. T. immigrans et T. caespitum produisent des hybrides dans les zones de sympatrie. La détection de rétrocroisements et de discordances entre ADN mitochondrial et nucléaire suggère que cette hybridation conduit à une descendance fertile, donc de l’introgression. Les profils d'hydrocarbures cuticulaires sont bien différenciés entre les deux espèces et sont corrélés à une agression forte contre les hétérospécifiques. Ces espèces présentent un système d'accouplement monogyne polyandre, dans lequel les reines hybrides mais pas les pères hybrides contribuent à la descendance hybride. Les études sur l'hybridation interspécifique n'ont qu'occasionnellement concerné les changements globaux ou invasions biologiques. Ces concepts eux-mêmes sont peu étudiés ensemble et leurs effets interactifs sont négligés dans la littérature actuelle. La prise en compte de ces interrelations et l'exploration de plusieurs échelles sont essentielles pour mieux comprendre les processus qui génèrent des modèles d'échange génétique / Climate change, urbanization, biological invasions and interspecific hybridization are major current threats to biodiversity. The objective of this thesis was to assess their interactive effects in Tetramorium ant species from the Rhône-Saône valley in France. Using a broad array of tools from several fields of biology, I worked on almost two thousand colonies from five Tetramorium species including T. immigrans and T. caespitum. Both climate and urbanization limited the ranges of these species, and urbanization impacted their distributions simultaneously at several spatial scales. The occurrence probabilities of T. immigrans depended on the interaction between climatic and urban factors. Several introductions from external sources seemed to have given rise to four genetically distinct populations of T. immigrans, making it likely that it is not native to the northernmost urban areas. Hybridization and introgression between T. immigrans and T. caespitum was frequent in zones of sympatry, and the detection of nuclear DNA backcrosses and mitochondrial-nuclear DNA discordance between the two species suggested that hybridization lead to fertile offspring (i.e. introgression). Cuticular hydrocarbon profiles were clearly differentiated between the two species and were correlated to heightened interspecific aggression against heterospecifics. Both species presented a monogyne polyandrous mating system, in which hybrid queens but no hybrid fathers contributed to hybrid offspring. Few studies on interspecific hybridization have addressed global change or biological invasions. These concepts are infrequently studied together, and their interactive effects are overlooked in the current literature. Taking these interrelationships into account and exploring multiple scales are essential to better understand the processes that generate patterns of genetic exchange
102

Does size really matter: how synchrony and size affect the dynamic of aggression between two sympatric species of dolphin in the Bahamas

Unknown Date (has links)
Bottlenose (Tursiops truncatus) and spotted (Stenella frontalis) dolphins are sympatric species, resident to Little Bahama Bank, Bahamas. A unique, dynamic methodology quantified how interspecific aggression changed over time in terms of the individuals participating, context, and behaviors used. The timing of human observation relative to the onset of aggression did not result in differences in the proportion of behaviors observed. Highly intense behaviors were used most often. The synchronous state of spotted dolphin groups, not the presence alone, was a crucial factor in determining the onset and progression of aggression. When synchronous, spotted dolphins successfully dominated the larger bottlenose dolphins. Two levels of dominance were observed. Within a single encounter ("encounter level"), one species did dominate the other. When all aggressive encounters were considered collectively over the long term ("gross level"), one species did not dominate the other. The combination of contextual factors best determined the dynamic of interspecific aggression. / by Jessica A. Cusick. / Thesis (M.S.)--Florida Atlantic University, 2012. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2012. Mode of access: World Wide Web.
103

La fourmi d’Argentine (Linepithema humile) face à une fourmi dominante du genre Tapinoma en milieu insulaire : écologie chimique, comportement et dynamique d’invasion

Berville, Laurence 07 June 2013 (has links)
La fourmi d'Argentine (Linepithema humile) est une des espèces invasives parmi les plus nuisibles au monde. Dans le cadre des invasions biologiques, les résistances biotiques sont souvent les dernières barrières des écosystèmes. Une hypothèse, jamais testé in natura, de résistance de la part d'une fourmi du genre Tapinoma face à L. humile a été émise. Pour le démontrer, nous avons choisi d'expérimenter en laboratoire et in natura. Nos terrains d'études privilégiés ont été, outres des sites du littoral méditerranéen français, 4 îles situées en face du littoral envahi par la fourmi d'Argentine. Parmi celles-ci, deux contiennent à la fois la fourmi d'Argentine et des espèces du genre Tapinoma. L'identification difficile des espèces du genre Tapinoma étant sujette à une controverse scientifique, nous avons dû différencier de façon certaine cinq d'entre elles, par leurs morphologies et leurs signatures chimiques. En Provence, trois espèces ont été observées : T. erraticum, T. madeirense et T. nigerrimum. Sur l'île de Ratonneau, un suivi sur 2 ans de la vitesse d'invasion de L. humile en milieu naturel, avec ou sans T. nigerrimum, met en évidence une vitesse d'invasion très faible, voire un recul dans la zone à T. nigerrimum. Les colonies de T. nigerrimum de l'île de Ratonneau semblent faire obstacle à la progression de l'invasion. Des études comportementales préliminaires, conduites en laboratoire, entre fragments de nids de T. nigerrimum et L. humile nous avaient permis de confirmer les capacités de T. nigerrimum à résister face à l'invasive. Ainsi, les ouvrières T. nigerrimum défendent mieux leurs territoires, allant jusqu'à accaparer celui des L. humile. / The Argentine ant (Linepithema humile) is one of the world's worst invasive species. We used various analyses to determine its invasion pattern on the Provence coast, confirming the presence of a second supercolony. Chemical and behavioral analyses of worker interactions on the supercolony border identified a peaceful border zone. When biological invasion occurs, biotic resistance is often ecosystems' last defense. Could a dominant ant from Tapinoma genus resist L. humile invasion? To demonstrate this possibility, we conducted both laboratory and in natura experiements. Besides the invaded Mediterranean coast, we selected four nearby islands, two of which were found to contain both L. humile and Tapinoma spp. Identification of Mediterranean Tapinoma being controversial, we used both morphological and chemical analyses to ensure reliable discrimination. On the coast, we found T. erraticum, T. madeirense and T. nigerrimum. In natura, on Ratonneau Island, two-year field monitoring showed a slow rate of Argentine ant invasion and even retreat, faced with T. nigerrimum. T. nigerrimum colonies seem to block L. humile invasion. Laboratory behavioral studies between nests of T. nigerrimum and L. humile confirm T. nigerrimum's ability to stand up to Argentine ants: T. nigerrimum workers protect and defend their territories better, even taking over Argentine ant nests.
104

攻擊行為控制機制之探討 / Exploring the Control Mechanism of Aggressive Behaviors

李怡青, Lee, I-Ching Unknown Date (has links)
本論文嘗試以行為引發機制與行為抑制機制的觀點,探討非法且屬人際層面的男性攻擊行為,從中評估常表現攻擊行為個體的認知、情緒與行為缺陷。由於攻擊行為的特殊性,個體表現攻擊行為時,相關的行為機制包括表現該行為可能得到獎賞的行為引發機制﹔表現該行為可能得到懲罰的行為抑制機制﹔與攻擊他人時,被害者的非語文訊息引發的個體的暴力抑制機制。研究一根據暴力抑制機制的理論內容發展實驗工具,透過違反道德與違反慣例圖片組的呈現,了解高、中、低攻擊組的表現差異。結果發現高攻擊組對兩違反情境的嚴重程度評估較低,同時,在違反道德圖片組刺激下,高攻擊組表現較少的道德情緒與較少的同理行為。研究二則透過研究一發展的圖片組評估個體的暴力抑制機制運作能力,並結合Patterson與Newman的四階段理論發展實驗刺激,透過情境的操弄,了解高攻擊組之行為引發機制與行為抑制機制運作情形。結果發現經由兩套理論(暴力抑制機制與四階段理論)的結合,可將高攻擊組分為兩類,一類為暴力抑制機制運作正常,但行為引發機制運作過強﹔另一類為暴力抑制機制無法運作者。以認知、情緒與行為缺陷評估兩類高攻擊行為者發現,具有認知、情緒與行為缺陷的高攻擊行為者只有第二類。 / Based on a behavioral activation mechanism and two behavioral inhibition mechanisms, unlawful and interpersonal male aggression was studied. Moreover, the possibility of individuals’ cognitive, emotional, and behavioral deficiencies was evaluated. Due to the special quality of aggressive behavior, when a person acts aggressively, there will be three processes involved. They are the behavioral activation mechanism activated by reward, the behavioral inhibition mechanism induced by punishment, and the Violence Inhibition Mechanism (VIM) triggered by victims’ cues of distress. In order to study these three processes, two sets of pictures were developed from study 1 in order to evaluate how participants functioned their VIM. The results showed differences between High, Medium, and Low Aggression Group. The High Aggression Group evaluated incidents of moral/ conventional transgression less serious than the other two groups did. Also, they showed less moral emotions and less empathic behaviors than the other two groups did. Based on the sets of pictures developed from Study 1, a group of young offenders were divided into two groups based on their VIM functioning. Further, a survival game was developed from Patterson and Newman’s four-stage model. By manipulating situations to present reward/punishment, those young offenders showed different aggressive patterns. Young offenders with good VIM functioning behaved more aggressively when there were rewards. Relatively, young offenders with poor VIM functioning were less likely to be influenced by either reward or punishment. The implications were discussed in the article.
105

Hysj : En kritisk didaktisk relasjonsanalyse av Curriculum Silentium; den skjulte policyen for taushet om arbeidsrelatert kritikk hos ansatte. / Shhhh! : A Critical Didactic Relations Analysis of the Curriculum Silentium; The Hidden Policy of Silence Regarding Work Related Crticism from Employees.

Holte, Kjersti Lien January 2009 (has links)
This study has developed a tool for explaining why employees fail to speak up with regard to work related criticism; there is a hidden policy of silence that teaches employees to remain silent. This hidden policy is here designated as the "Curriculum Silentium" and is described in detail on the basis of empirical and theoretical data. After identifying a gap between the intentionally and experienced policy for employees freedom of speech in organizations I suggest that there are on-going unofficial, partially hidden learning processes in the organizations. The overall research question is; How does the Curriculum Silentium; the hidden policy of silence among employees, look like?  I make an analytic construction of the hidden policy as if it were planned policy, using the didactic categories applicable to organizations. These didactic categories are: goals, content, teaching strategies and the motivation of employees. The empirical data was collected in three different organizations: an elementary school, a home for the elderly and a factory in the process industry, using qualitative methods such as interviews and observation. The theoretical foundation of the study is taken from existing theory within the field of work life research and educational science. The study is not a comparative study of the three organizations, but does involve a comparison of whether and how the Curriculum Silentium is expressed in three such different organizations. The challenge of examining hidden relationships in organizations was met through the development of guidelines for an analytical approach called a critical didactic relations analysis. The study concludes that a hidden policy of silence resembling that presented here exists in organizations where employees fail to voice working life related criticism.
106

Efeitos do decanoato de nandrolona na homeostasia glutamatérgica e no comportamento agressivo

Kalinine, Eduardo January 2014 (has links)
Nos últimos anos, houve um aumento significativo no uso abusivo dos Esteróides Anabólicos Andrógenos (EAAs). Um dos efeitos comportamentais mais marcantes da administração crônica de EAAs como o Decanoato de Nandrolona (DN) é a indução do comportamento agressivo exacerbado. Atualmente o sistema glutamatérgico tem sido associado ao comportamento agressivo induzido pelos EAAs, principalmente no que se refere à modulação dos receptores N-Methyl-D-Aspartato NMDA (NMDAr). Nós investigamos os efeitos centrais e periféricos da administração do DN ao longo do tempo (4, 11 e 19 dias consecutivos de administração), e a participação de mecanismos glutamatérgicos. Para isso, camundongos CF-1 tratados com DN foram avaliados em relação ao comportamento agressivo pelo teste do intruso. Além disso, investigamos a captação de glutamato, o imunoconteúdo de GLT-1, os níveis de glutamato no líquido extracelular, e a participação dos NMDAr na manifestação do comportamento agressivo. O fenótipo agressivo foi evidenciado somente no longo tempo de exposição à DN (19 dias). Na mesma janela temporal que os animais apresentaram o fenótipo agressivo houve redução significativa de captação de glutamato em fatias cerebrais de córtex e hipocampo, como também a redução do imunoconteúdo do transportador astrocitário GLT-1 nas mesmas estruturas cerebrais. A administração de antagonistas de NMDAr como MK-801 e memantina antes do teste do intruso diminuiu o comportamento agressivo dos animais tratados cronicamente com DN a níveis iguais aos do grupo controle. Ainda, o comportamento agressivo induzido pela administração crônica de DN diminuiu a remoção do glutamato da fenda sináptica, culminando com o aumento do glutamato extracelular no SNC, o que resultou na hiperexcitabilidade dos NMDAr. Este trabalho enfatiza o papel da comunicação entre astrócitos e neurônios e a relevância da hiperstimulação de NMDAr na manifestação do comportamento agressivo. / Nandrolone decanoate (ND), an anabolic androgenic steroid (AAS), induces an aggressive phenotype by mechanisms involving glutamate-induced N-methyl-d-aspartate receptor (NMDAr) hyperexcitability. The astrocytic glutamate transporters remove excessive glutamate surrounding the synapse. However, the impact of supraphysiological doses of ND on glutamate transporters activity remains elusive. We investigated whether ND-induced aggressive behavior is correlated with GLT-1 activity, glutamate levels and abnormal NMDAr responses. Two-month-old untreated male mice (CF1, n=20) were tested for baseline aggressive behavior in the resident-intruder test. Another group of mice (n=188) was injected with ND (15mg/kg) or vehicle for 4, 11 and 19 days (short-, mid- and long-term endpoints, respectively) and was evaluated in the resident-intruder test. Each endpoint was assessed for GLT-1 expression and glutamate uptake activity in the frontoparietal cortex and hippocampal tissues. Only the long-term ND endpoint significantly decreased the latency to first attack and increased the number of attacks, which was associated with decreased GLT-1 expression and glutamate uptake activity in both brain areas. These alterations may affect extracellular glutamate levels and receptor excitability. Resident males were assessed for hippocampal glutamate levels via microdialysis both prior to, and following, the introduction of intruders. Long-term ND mice displayed significant increases in the microdialysate glutamate levels only after exposure to intruders. A single intraperitoneal dose of NMDAr antagonists, memantine or MK-801, shortly before the intruder test, decreased aggressive behavior. In summary, long-term ND-induced aggressive behavior is associated with decreased extracellular glutamate clearance and NMDAr hyperexcitability, emphasizing the role of this receptor in mediating aggression mechanisms.
107

Efeitos do decanoato de nandrolona na homeostasia glutamatérgica e no comportamento agressivo

Kalinine, Eduardo January 2014 (has links)
Nos últimos anos, houve um aumento significativo no uso abusivo dos Esteróides Anabólicos Andrógenos (EAAs). Um dos efeitos comportamentais mais marcantes da administração crônica de EAAs como o Decanoato de Nandrolona (DN) é a indução do comportamento agressivo exacerbado. Atualmente o sistema glutamatérgico tem sido associado ao comportamento agressivo induzido pelos EAAs, principalmente no que se refere à modulação dos receptores N-Methyl-D-Aspartato NMDA (NMDAr). Nós investigamos os efeitos centrais e periféricos da administração do DN ao longo do tempo (4, 11 e 19 dias consecutivos de administração), e a participação de mecanismos glutamatérgicos. Para isso, camundongos CF-1 tratados com DN foram avaliados em relação ao comportamento agressivo pelo teste do intruso. Além disso, investigamos a captação de glutamato, o imunoconteúdo de GLT-1, os níveis de glutamato no líquido extracelular, e a participação dos NMDAr na manifestação do comportamento agressivo. O fenótipo agressivo foi evidenciado somente no longo tempo de exposição à DN (19 dias). Na mesma janela temporal que os animais apresentaram o fenótipo agressivo houve redução significativa de captação de glutamato em fatias cerebrais de córtex e hipocampo, como também a redução do imunoconteúdo do transportador astrocitário GLT-1 nas mesmas estruturas cerebrais. A administração de antagonistas de NMDAr como MK-801 e memantina antes do teste do intruso diminuiu o comportamento agressivo dos animais tratados cronicamente com DN a níveis iguais aos do grupo controle. Ainda, o comportamento agressivo induzido pela administração crônica de DN diminuiu a remoção do glutamato da fenda sináptica, culminando com o aumento do glutamato extracelular no SNC, o que resultou na hiperexcitabilidade dos NMDAr. Este trabalho enfatiza o papel da comunicação entre astrócitos e neurônios e a relevância da hiperstimulação de NMDAr na manifestação do comportamento agressivo. / Nandrolone decanoate (ND), an anabolic androgenic steroid (AAS), induces an aggressive phenotype by mechanisms involving glutamate-induced N-methyl-d-aspartate receptor (NMDAr) hyperexcitability. The astrocytic glutamate transporters remove excessive glutamate surrounding the synapse. However, the impact of supraphysiological doses of ND on glutamate transporters activity remains elusive. We investigated whether ND-induced aggressive behavior is correlated with GLT-1 activity, glutamate levels and abnormal NMDAr responses. Two-month-old untreated male mice (CF1, n=20) were tested for baseline aggressive behavior in the resident-intruder test. Another group of mice (n=188) was injected with ND (15mg/kg) or vehicle for 4, 11 and 19 days (short-, mid- and long-term endpoints, respectively) and was evaluated in the resident-intruder test. Each endpoint was assessed for GLT-1 expression and glutamate uptake activity in the frontoparietal cortex and hippocampal tissues. Only the long-term ND endpoint significantly decreased the latency to first attack and increased the number of attacks, which was associated with decreased GLT-1 expression and glutamate uptake activity in both brain areas. These alterations may affect extracellular glutamate levels and receptor excitability. Resident males were assessed for hippocampal glutamate levels via microdialysis both prior to, and following, the introduction of intruders. Long-term ND mice displayed significant increases in the microdialysate glutamate levels only after exposure to intruders. A single intraperitoneal dose of NMDAr antagonists, memantine or MK-801, shortly before the intruder test, decreased aggressive behavior. In summary, long-term ND-induced aggressive behavior is associated with decreased extracellular glutamate clearance and NMDAr hyperexcitability, emphasizing the role of this receptor in mediating aggression mechanisms.
108

Efeitos do decanoato de nandrolona na homeostasia glutamatérgica e no comportamento agressivo

Kalinine, Eduardo January 2014 (has links)
Nos últimos anos, houve um aumento significativo no uso abusivo dos Esteróides Anabólicos Andrógenos (EAAs). Um dos efeitos comportamentais mais marcantes da administração crônica de EAAs como o Decanoato de Nandrolona (DN) é a indução do comportamento agressivo exacerbado. Atualmente o sistema glutamatérgico tem sido associado ao comportamento agressivo induzido pelos EAAs, principalmente no que se refere à modulação dos receptores N-Methyl-D-Aspartato NMDA (NMDAr). Nós investigamos os efeitos centrais e periféricos da administração do DN ao longo do tempo (4, 11 e 19 dias consecutivos de administração), e a participação de mecanismos glutamatérgicos. Para isso, camundongos CF-1 tratados com DN foram avaliados em relação ao comportamento agressivo pelo teste do intruso. Além disso, investigamos a captação de glutamato, o imunoconteúdo de GLT-1, os níveis de glutamato no líquido extracelular, e a participação dos NMDAr na manifestação do comportamento agressivo. O fenótipo agressivo foi evidenciado somente no longo tempo de exposição à DN (19 dias). Na mesma janela temporal que os animais apresentaram o fenótipo agressivo houve redução significativa de captação de glutamato em fatias cerebrais de córtex e hipocampo, como também a redução do imunoconteúdo do transportador astrocitário GLT-1 nas mesmas estruturas cerebrais. A administração de antagonistas de NMDAr como MK-801 e memantina antes do teste do intruso diminuiu o comportamento agressivo dos animais tratados cronicamente com DN a níveis iguais aos do grupo controle. Ainda, o comportamento agressivo induzido pela administração crônica de DN diminuiu a remoção do glutamato da fenda sináptica, culminando com o aumento do glutamato extracelular no SNC, o que resultou na hiperexcitabilidade dos NMDAr. Este trabalho enfatiza o papel da comunicação entre astrócitos e neurônios e a relevância da hiperstimulação de NMDAr na manifestação do comportamento agressivo. / Nandrolone decanoate (ND), an anabolic androgenic steroid (AAS), induces an aggressive phenotype by mechanisms involving glutamate-induced N-methyl-d-aspartate receptor (NMDAr) hyperexcitability. The astrocytic glutamate transporters remove excessive glutamate surrounding the synapse. However, the impact of supraphysiological doses of ND on glutamate transporters activity remains elusive. We investigated whether ND-induced aggressive behavior is correlated with GLT-1 activity, glutamate levels and abnormal NMDAr responses. Two-month-old untreated male mice (CF1, n=20) were tested for baseline aggressive behavior in the resident-intruder test. Another group of mice (n=188) was injected with ND (15mg/kg) or vehicle for 4, 11 and 19 days (short-, mid- and long-term endpoints, respectively) and was evaluated in the resident-intruder test. Each endpoint was assessed for GLT-1 expression and glutamate uptake activity in the frontoparietal cortex and hippocampal tissues. Only the long-term ND endpoint significantly decreased the latency to first attack and increased the number of attacks, which was associated with decreased GLT-1 expression and glutamate uptake activity in both brain areas. These alterations may affect extracellular glutamate levels and receptor excitability. Resident males were assessed for hippocampal glutamate levels via microdialysis both prior to, and following, the introduction of intruders. Long-term ND mice displayed significant increases in the microdialysate glutamate levels only after exposure to intruders. A single intraperitoneal dose of NMDAr antagonists, memantine or MK-801, shortly before the intruder test, decreased aggressive behavior. In summary, long-term ND-induced aggressive behavior is associated with decreased extracellular glutamate clearance and NMDAr hyperexcitability, emphasizing the role of this receptor in mediating aggression mechanisms.
109

Vespas sociais (Hymenoptera, Vespidae) em áreas antrópicas

Alvarenga, Raphaela de Barros 10 February 2012 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-05-20T19:17:03Z No. of bitstreams: 1 raphaeladebarrosalvarenga.pdf: 736205 bytes, checksum: f06192e913497d47b4706db973f03b3c (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-07-02T11:28:01Z (GMT) No. of bitstreams: 1 raphaeladebarrosalvarenga.pdf: 736205 bytes, checksum: f06192e913497d47b4706db973f03b3c (MD5) / Made available in DSpace on 2016-07-02T11:28:01Z (GMT). No. of bitstreams: 1 raphaeladebarrosalvarenga.pdf: 736205 bytes, checksum: f06192e913497d47b4706db973f03b3c (MD5) Previous issue date: 2012-02-10 / As vespas sociais estão amplamente distribuídas em todo o continente. No ambiente urbano tem se observado a nidificação de algumas espécies de vespas sociais em locais próximos a presença humana, como por exemplo, a espécie Mischocyttarus cassununga. Os objetivos deste trabalho foram verificar a ocorrência de vespas sociais em jardins urbanos, durante a estação quente e úmida; e fria e seca e avaliar a agressividade, o comportamento de defesa e o desenvolvimento das colônias de M. cassununga, diante de perturbações nos ninhos e simulação de ataques de formigas, no município de Juiz de Fora, Minas Gerais. Para verificar a ocorrência de vespas sociais em jardins urbanos, o estudo foi conduzido durante um ano, em sete jardins urbanos, com seis vistorias em cada estação. Durante a estação quente e úmida foram encontradas 145 colônias: Protopolybia exigua (n= 81), Polybia platycephala (n=40) e Mischocyttarus cassununga (n=24). Já na estação fria e seca foram encontradas 87 colônias: P. exigua (n=47), P. platycephala (n=29) e M. cassununga (n=11). Na estação quente e úmida a densidade foi superior para todas as espécies. Nas duas estações o índice de dominância para as colônias de P. exigua (d=0,55) foi superior em relação às outras espécies encontradas (d= 0,30 para P. platycephala e d=0,15 para M. cassununga). Todas as colônias nidificavam em vegetação: Livistona chinensis (n=161) e Dracaena fragans (n=71). O número de colônias encontradas demonstrou uma forte correlação positiva com o tamanho da área verde arbórea (r=0,9643; p=0,0005) e com o tamanho da área verde de nidificação (r=0,8571; p=0,0137), assim como com o tamanho da área total dos jardins urbanos(r=0,9286; p=0,0025). A altura das colônias em relação ao solo variou de dois a mais de quatro metros. As espécies que estavam entre dois e quatro metros de altura foi significativamente maior (χ²=21,930; p<0,0001) do que as colônias encontradas nas demais alturas. Para avaliar o comportamento de defesa da espécie M. cassununga, o estudo foi realizado entre os meses de abril a julho de 2011 no campus da Universidade Federal de Juiz Fora, utilizando-se sete colônias controle e sete colônias tratamento. As colônias foram mapeadas e durante 18 dias as colônias tratamento foram perturbadas com uma bola de malha vermelha agitada. Posteriormente foi feita uma simulação de ataque de formigas contra todas as colônias (controle e tratamento). Os resultados mostraram que durante a perturbação com a bola as colônias se apresentaram mais agressivas no começo e possivelmente se habituaram a bola com o decorrer da perturbação. Durante a simulação de ataque de formigas, não houve diferença significativa (z=0,133; p=0,895) na freqüência comportamental entre as colônias controle e tratamento. O desenvolvimento dos imaturos também não demonstrou diferença significativa para ovos (z=1,351; p=0,177), larvas (z=1,293; p=0,196) e pupas (z=0,925; p=0,355) entre as colônias controle e tratamento. Porém houve uma diferença significativa (z=2,300; p=0,021) no desaparecimento de ovos entre as colônias controle e tratamento. Houve também uma diferença significativa entre o desaparecimento de larvas das colônias controle e tratamento de M. cassununga (z=2,108; p=0,035). Com este estudo foi possível perceber que há uma maior ocorrência das vespas sociais na estação quente e úmida em jardins urbanos e uma relação direta entre a presença de recursos oferecidos nesta estação e a ocorrência de vespas sociais. Foi possível demonstrar também que apesar da baixa agressividade, as colônias de M. cassununga exibem comportamentos agressivos em defesa de suas colônias e que as perturbações influenciam no desaparecimento de imaturos (ovos e larvas), diminuindo o surgimento de novos adultos. / The social wasps are widely distributed around the continent. In the urban environment has been observed the nesting of some social wasps species and their socialization with the human presence, for exemple the specie Mischocyttarus cassununga. The objectives of this study were to verify the occurrence of social wasps in urban gardens during the hot, humid, cold and dry and evaluate their aggression, and colonies defensive behavior development of M. cassununga, about turmoil in nests and of ants attacks simutalions, in the Juiz de Fora municipality , Minas Gerais. To check the occurrence of social wasps in urban gardens, the study was conducted during one year in seven urban gardens, making six surveys at each station. During the hot and humid 145 colonies were found: Protopolybia exigua (n=81), Polybia platycephala (n=40) and Mischocyttarus cassununga (n=24). In the cold season and dry 87 colonies were found: P. exigua (n=47), P. platycephala (n=29) and M. cassununga (n=11). In the hot and humid the density was higher in all species. In two seasons "the" dominance index for colonies of P. exigua (d=0.55) was superior compared to other species found (d=0.30 for P. platycephala and d=0.15 for M. cassununga). All colonies nesting in vegetation: Livistonia chinensis (n=161) and Dracaena fragans (n=71). The number of colonies found showed a strong positive correlation with the size of green tree (r=0.9643, p=0.0005) and with the size of nesting green area (r=0.8571, p=0.0137), as well as the total area size of urban gardens (r=0.9286, p=0.0025). The height colonies from the ground ranged from two tand four meters more. The species that was between two and four meters in height was significantly higher (χ²=21.930; p<0.0001) than those found in other colonies heights. To evaluate the defense of M. cassununga specie, the study was conducted between April and July 2011 on the campus of University Juiz de Fora, using seven control colonies and seven treatment colonies. The colonies were mapped and during 18 days the treatment colonies were disturbed by a agitated restless ball of red. It was later made a mock attack against all ant colonies (control and treatment). The results showed during the disturbance with the ball the colonies had more aggressive in the beginning and possibly have accustomed to the ballduring the perturbation. During the attack simulation by ants, there was no significant difference (z=0.133, p=0.895) in the behavior frequency between control and treatment colonies. The immature development also showed no significant difference for eggs (z=1.351, p=0.177), larvae (z=1.293, p=0.196) and pupas (z=0.925, p=0.355) between control colonies and treatment colonies. However, there was a significant difference (z=2.300, p=0.021) in disappearance of eggs between the control and treatment colonies. There was also a significant difference between the disappearance of larvae from control and treatment colonies M. cassununga (z=2.108, p=0.035). With this study it was revealed that there is a higher occurrence of social wasps in the hot season and humid in urban gardens and a direct relationship between the features presence offered in this season and the occurrence of social wasps. It was also possible to demonstrate that despite the low aggressiveness, the colonies M. cassununga showed aggressive behavior in defense of their colonies and that disturbances influence the disappearance of immature (eggs and larvae), reducing the emergence of new adults.
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Le rôle médiateur du biais d’attribution d’intention hostile dans la relation entre l’agressivité et la personnalité antisociale : une étude des potentiels reliés aux évènements

Ursulet, Adriana 08 1900 (has links)
Tous les jours, dans le monde, des comportements agressifs sont commis à l’égard d’individus, causant des préjudices physiques, psychologiques et financiers. En réponse à une provocation, ces agressions sont dites réactives et peuvent être alimentées par des biais cognitifs d’attribution d’intention hostile et des styles de personnalité antisociale. Comblant un trou dans la littérature scientifique, cette étude a pour but d’évaluer le biais d’attribution d’intention hostile ainsi que son rôle dans la relation entre la personnalité antisociale et l’agressivité réactive. Dans cette perspective, les participants étaient invités à répondre à des questionnaires évaluant la personnalité, les processus cognitifs et l’agressivité. Puis, pendant l’enregistrement de leur activité cérébrale, ils devaient lire des scénarios d’interactions sociales et attribuer une intention aux comportements décrits comme ambigus et provocateurs. Nous avons analysé la N400, une composante de potentiels reliés aux évènements, associée à la présentation d’intentions inattendues hostiles ou non hostiles après chaque scénario. Des analyses de corrélations de Pearson et de régressions linéaires multiples ont été réalisées pour examiner la validité de notre modèle de médiation. Les résultats montrent que la N400 est plus forte lors de la présentation d’intention non hostile inattendue que lors de la présentation d’intention hostile inattendue dans les régions centropariétales. La personnalité antisociale et la violation des attentes hostiles étaient reliées positivement à l’agressivité réactive. La personnalité antisociale prédisait l’agressivité réactive même à l’ajout de la violation des attentes hostile (Z = .30, p = .76) ou de la violation des attentes non hostiles (Z = -.32, p = .75) comme médiateur. En somme, le rôle médiateur du biais d’attribution d’intention n’est pas confirmé et d’autres études sont nécessaires pour mieux comprendre le lien entre la personnalité antisociale et l’agressivité réactive. / Every day, around the world, aggressive behaviors are committed against individuals, causing physical, psychological and financial harm. In response to provocation, these assaults are said to be reactive and can be fuelled by cognitive biases of attributing hostile intent and antisocial personality styles. Filling a gap in the scientific literature, the purpose of this study is to evaluate hostile intent bias and its role in the relationship between antisocial personality and reactive aggression. To this end, participants were asked to complete questionnaires assessing personality, cognitive processes and aggression. Then, while recording their brain activity, they were asked to read scenarios of social interactions and to attribute intent to behaviors described as ambiguous and provocative. We analyzed the N400, an event-related potential component associated with the presentation of unexpected hostile or non-hostile intentions after each scenario. Pearson correlation and multiple linear regression analyses were performed to examine the validity of our mediation model. The results show that the N400 is stronger in the presentation of unexpected non-hostile intent than in the presentation of unexpected hostile intent in the centro-parietal regions. Antisocial personality and violation of hostile expectations were positively related to reactive aggression. Antisocial personality predicted reactive aggression even with the addition of hostile expectation violation (Z = .30, p = .76) or non-hostile expectation violation (Z = -.32, p = .75) as a mediator. In sum, the mediating role of intention attribution bias is unconfirmed and further studies are needed to better understand the link between antisocial personality and reactive aggression.

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