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Aggression clearly has an adaptive value as it is necessary to secure resources for survival, growth, and reproduction. The Siamese fighting fish, Betta splendens, have endured a prolonged process of artificial selection for winning paired-fight contests across Southeast Asia, resulting in strains of short-fin aggressive “fighters”. Across centuries, Thai breeders have been selecting these strains by discarding loser batches and allowing winner batches to breed, claiming that they are significantly more aggressive than wild-types. This natural experiment provides a powerful context to investigate the biological basis of aggressive behaviour in fish, the topic of this thesis. To study aggression, it is important to validate and standardize behavioural assays appropriate for the species under study. Further, different aggression-eliciting stimuli, such as live opponents, 3D models, video playback, or mirror images, may elicit non-equivalent behavioural and physiological responses. For B. splendens, in particular, quantifying aggression from live fights is not ethically acceptable as the high levels of aggression of this species usually result in injuries or even death of the opponent. In Chapter II, it was shown that mirror images elicit very similar aggressive displays and endocrine responses to an interacting opponent behind a transparent partition, validating the use of this test to measure aggression in this model species. Further, it was shown that circulating levels of both androgens (11-ketotestosterone and testosterone) and corticosteroids (cortisol) increased in response to the aggression challenge, even in the absence of conflict resolution, questioning the role of these hormones during present and future aggressive contests. Using the previously validated mirror assay and also tests with live conspecifics, we assessed the impact of selection for winning by comparing, in Chapter III, male and female aggressive behaviour of lab-raised fighter and wild-type strains. The hypothesis that selection for male winners enhanced aggressive displays was confirmed, suggesting that the duration and frequency of threat and attack behaviour correlates with winning probability. However, females of the fighter strain, which are not selected for fights, were also more aggressive than wild-type females. This suggests that male and female aggression share common genetic pathways and physiological mechanisms and raises the possibility that selection for alleles that favour male aggression may have promoted intersexual genetic conflict in this species. After confirming the expected differences in aggressive behaviour between fighter and wild-type fish, the following question was whether endocrine systems, in particular those previously shown to respond to aggression, could have been targeted by the selection process. From previous studies in fish and other vertebrates, it was hypothesised that selection for winners could have increased constitutive levels of androgens or led to an enhanced androgen response to a social challenge. However, in chapter IV, it was shown that levels of 11-ketotestosterone and its response to aggression was similar in males of both strains, questioning the role of androgens in the modulation of aggression in B. splendens. On the contrary, constitutive levels of cortisol and the response of this hormone to an aggression challenge were higher in wild-type compared with fighter fish, supporting previous findings that associated high aggression with a blunted cortisol response. Overall, results from Chapter IV suggest that selection for winning had a stronger impact on the hypothalamus-pituitary-interrenal axis than in the hypothalamus-pituitary-gonadal axis. My results support the assumption of the “Challenge Hypothesis” proposed by John Wingfield and collaborators in 1990 to explain the relationship between androgens and aggression, according to which androgen levels above a reproductive baseline are a consequence of the frequency and intensity of social interactions, in particular of male-male agonistic encounters. It is becoming clear that androgens increase rapidly after an aggressive contest, independently of fight outcome. However, the function of this increase remains unclear as the frequency of aggressive displays was unrelated with post-fight androgen levels and constitutive levels of androgens, and androgen responsiveness, were similar between fighter and wild-type males. Results obtained for cortisol agree with a “corticosteroid-mediated dominance hypothesis” whereby low baseline levels and a blunted response of corticosteroids would be associated with a dominant status and high aggression. The work advances our knowledge about the endocrine regulation of aggressive behaviour in B. splendens and opens several testable hypotheses about the role of androgens and corticosteroids in the regulation of fish aggressive behaviour
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The main focus of this thesis was to characterize the patient information leaftlets as a text genre in Portugal, compare it with the same text genre in other countries and propose a new form of elaborating these documents in order to rise its comprehensibility levels. Therefore, we proceeded with an analysis of the patient information leaflet as a text genre and its relationship with text linguistics and translation. We also analyzed a corpus of 50 patient information leaflets with focus not only on its content, but also in the way they were created. In order to know the opinion of the general public, a survey about the situation of these documents in Portugal was distributed. In order to find the differences between these documents in different contexts, we made a comparison of a portuguese leaflet with leaflets from other countries. By last, we proposed a new writing scheme for these documents, reformulating one of the leaflets analyzed in the corpus and, to get the opinion of the general public, distributing a survey where the reformulated version was compared to the original one. The results point out to a lack of uniformity between documents and the way that they are created in pharmaceutical companies. The content of the patient informations leaflets in Portugal has an excess of text, technical language and a visual organization that is not appealing, problems that were also pointed out by the public in a survey. In the comparison between leaflets of different countries, big differences were found even when they were produced by the same company. When confronted with the original version and the reformulated version of the same document, the general public prefered the latter.
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Buddhism was founded by Shakyamuni, and this religion has appeared in opposition to Brahmanism's caste system since its inception. Shakyamuni emphasized the important concept of “all beings are equal” from the very beginning. Buddhism spread from India to other regions, and was introduced to China through Central Asia. In China, Buddhism merged the two native cultures of Confucianism and Taoism and finally produced the socalled Chinese Buddhism. Buddhism and its value of equality were also developed and extended in China, and finally spread to Japan. After Buddhism was spread to Japan, it developed rapidly due to official support. Different Buddhist sects have established their own temples in Japan, and among them, Zen Buddhism has the greatest influence among all social classes in this country. Later, after years of development, Zen Buddhism penetrated into many aspects of Japanese culture, such as religion, aesthetics, garden design, samurai spirit and tea ceremony. With the spread of Zen Buddhism, the core value of Buddhism which is “Buddhist concept of equality” was also spread to Japan. The tea ceremony is precisely the place where this value of equality can be detected. This dissertation explains the many processes that reflect this value no matter inside or outside the tea room, and argues that the spirit of the tea ceremony is to pursue the value of equality
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