Rhythms of anorexigenic neuropeptides in senegalese sole: Effects of light, feeding regimes and developmental stage.

Increasing knowledge on the endocrine mechanisms that regulate feeding and growth in cultured fish can contribute to make improvement in fish holding conditions and feeding strategies, supporting the development of new techniques that could ameliorate feeding, food conversion efficiency and growth in aquaculture practice. The main objective of this study was to investigate how daily mRNA expression of three specific anorexigenic hormones, i.e. the corticotropin-releasing hormone (CRH) and the paralogues α- and β- proopiomelanocortin (POMC), is modulated by different photoperiods, light spectra and feeding regimes, in both adult and larvae of Solea senegalensis. In addition, as Senegalese sole exhibits a shift from diurnal to nocturnal in locomotor activity and feeding habits during metamorphic process, we tried to elucidate if this shift is accompanied by relevant daily variations in the expression of these anorexigenic hormones before, during and after the completion of metamorphosis. In order to reach this main objective, three main experiments were developed. In a first experiment, adults were reared under LD (12 h light: 12h dark) cycle and fed at mid-light (ML), mid-dark (MD) and at random (RND). In a second experiment, adult specimens were reared in constant darkness (DD) and fed at subjective mid-light (sML) or at RND. Larvae of Senegalese sole were reared under LD cycle with white, blue or red light for 40 days. Our results show an independence of crh mRNA expression from the feeding time and suggest an endogenous control of crh expression in sole. Both pomc paralogues showed significant daily rhythms under LD conditions. The rhythms were maintained or were even more robust under DD conditions for pomc_a, but were completely abolished for pomc_b. Our results indicate an endogenous control of pomc_a expression by the molecular clock in telencephalon and diencephalon, but not in the pituitary gland. Our findings confirm for the first time the significant influence that ambient lighting has on larval growth and development in Senegalese sole, revealing an important effect of light spectra upon functional elements of this species. Our results also emphasize the importance of maintaining cycling light-dark conditions of the adequate wavelengths in aquaculture practices during early development of sole.

La traduzione saggistica: tradurre il saggio Light Years Ahead

The aim of this dissertation is to demonstrate how theory and practice are linked in translation. The translation of the essay Light Years Ahead helped me to understand this connection and to develop the two main thesis included in this work, that is the possibility the translator has to choose among all the different theories, without giving one or another the absolute supremacy, and the diversity of the non-fiction genre. Therefore, the first chapter focuses on the different theories of translation, presented in a way which suggests that one might be the completion and the development of another. The second chapter deals with the peculiar issues of non-fiction translation, with particular attention to the way in which this genre gathers different elements of other text types. Despite this variety, it is also claimed that the function at the higher level of an essay is always the informative one. This concept led me to simplify and make more intelligible the Italian version of the text I translated (Light Years Ahead). In the third chapter, this last point is discussed, as well as my considerations about the function, the dominant aspect and the cultural analysis of the text, with particular regard to how the quality of the English translation affected my choices. In the fourth chapter I included some examples of translation, which best demonstrate the distinctive variety of styles of non-fiction texts and the possibility for the translator to choose each time which theory suits them best. Finally, I also included three examples which represent a sort of defeat for me, that is to say three points where the ambiguity of the text obliged me to remove that information for the sake of the dominant informative function.