Many studies have been conducted on the effect of size-grading in other fish species. However, there is a paucity of scientific information on the effects of size variation on cannibalism of juvenile dusky kob. Thus, a study focusing on the effect of size variation on juvenile dusky kob aggressive and feeding (browsing) behaviours was conducted. Three separate groups of hatchery-reared juvenile dusky kob of were obtained from Oceanwise (Pty) Ltd for use in a series of three experimental trials. In all trials, juvenile fish of the same age were size-graded and the COV-value was used to determine the size variation. The focal fish (largest fish) was exposed to groups of fish with different size variation for 30-min. behavioural observations before and after feeding in randomised trials. The first experimental trial (Chapter 2) quantified the effect of increasing size variation and observation time on the aggressive and browsing behaviours of juvenile dusky kob. On average, juvenile dusky kob weighed 3.60 ± 0.68 g fish-1 and measured 5.8 ± 0.41 mm. Each focal fish was observed (a) before feeding in the morning, (b) 2 h after feeding, (c) 6 h after feeding and (d) 12 h after feeding. Fish increased browsing behaviours (averaging 6.60 ± 0.56) and decreased intimidating aggressive behaviours (18.60 ± 1.39) 12 h after feeding. Other aggressive behaviours occurred but did not differ between observation times. Aggressive and browsing behaviours positively correlated with size variation variables, predominantly, 12 h after feeding. An average frequency of 19 chases were observed positively correlated with size variation, followed by average frequencies of 17 body bites and browses, and 11 tail bites per 30 min. Some behaviours including average frequencies of 0.2 chases, 4 tail bites, 2.4 intimidating and 0.3 browsing behaviours negatively correlated with the size variation, generally closer to the last meal. These preliminary observations thus showed that fish have become hungry approximately 6-12 h after feeding and substituted certain behaviours for others as time after feeding passed and as size variation increased. The second experimental trial (Chapter 3) consisted of the observations further testing the relationship between aggressive behaviours and size variation of juveniles of dusky kob averaging 0.43 ± 0.27 g fish-1. The focal fish was exposed to groups of fish of four size variation (COV) treatments for observations before and 12 h after feeding. Aggressive behaviours positively correlated with size variation both before and 12 h after feeding. An average frequency of 437 body bites positively correlated more often with COV, followed by average frequencies of 365 intimidating behaviours and 199 tail bites per 30 min., respectively, before and 12 h after feeding. The least often exhibited aggressive behaviours averaged 26 chases while positively correlating with size variation on the times specified. An average frequency of 311 intimidating behaviours before and after feeding including average of 28 tail bites after feeding negatively correlated with size variation. This may relate to shift of behaviours depending on the needs and capacity of the fish. Apparently, aggressive fish can change its behaviour as a function of COV-values rather than the mean size of the other fish. The third trial (Chapter 4) investigated the effect of the aggressor’s (focal fish) size in relation its aggressive and browsing behaviours to other fish (non-focal fish). Juvenile fish used for this trial, on average, weighed 30 ± 7.63 g fish-1. Aggressive and browsing behaviours were observed in four treatments of a) high COV and mean weight below, b) low COV and mean weight less, c) high COV and mean weight equivalent to and d) low COV and mean weight higher than that of the focal fish. Increased frequencies of aggressive and browsing behaviours per 30 min. occurred in treatment A, sharing similar frequencies in treatment C, compared to the other treatments (B and D) which shared certain frequencies. The intimidating behaviours predominated, followed by browsing, body bites, chases and tail bites, respectively. The results of the overall study suggest that the time passed after feeding and increasing size variation and differences facilitated aggressive and browsing behaviours in juvenile dusky kob. Dusky kob showed increasing aggressive behaviours as early as in the first two weeks after hatching, averaging 0.43 ± 0.27 g fish-1 with the frequency correlating with size differences. Consistent size-grading technique in the same-age fish should be used to manage size variation associated with aggressive behaviours. The period of about 4-6 h after feeding may explain the noticeable increased aggressive and browsing behaviours. Thus, fish should be fed immediately before or after evacuation of their guts to maintain less-aggressive behaviours of juvenile dusky kob. Fish generally increased aggressive and browsing acts before and long time after feeding than closer to after feeding. The study has provided the fundamental scientific groundwork for fish farmers and future researchers can further explore size variation, time after feeding and gut evacuation rate as critical components of aggressive behaviours. The scientific knowledge of aggressive and cannibalistic behaviours has essential application in farming management to achieve improved survival and growth rates in juvenile fish.

Les stratégies thérapeutiques anticancer sont nombreuses et variées. Elles visent à déclencher la mort des cellules tumorales mais les processus de mort cellulaire diffèrent en fonction du traitement, du type de cellule ciblé et des caractéristiques du patient. A côté des mécanismes classiques tels que l’apoptose et la nécrose, on retrouve également du cannibalisme cellulaire dans les biopsies de tumeurs des patients. Ce phénomène dont les mécanismes sont encore peu caractérisés, correspond à l’internalisation d’une cellule vivante par une cellule vivante. Il est fréquemment suivi par la dégradation de la cellule internalisée. Cette modalité de mort atypique est intéressante car nous avons montré qu’elle pouvait être modulée par des traitements anticancéreux et des études ont également démontré qu’elle pouvait servir de biomarqueur pronostique dans certains types de cancer. Ces travaux de thèse ont permis d'identifier des voies de signalisation cellulaire activées lors du déclenchement du cannibalisme cellulaire par les radiations ionisantes / Many types of anticancer therapies are available to kill tumor cells. The tumoral cell death modalities may be different upon the treatment, the cell type and inter-individual sensitivity. Besides the typical cell death processes apoptosis and necrosis, cellular cannibalism has also been reported in patients’ tumoral biopsies. This cellular process is defined as the engulfment of one live cell by another live cell followed by the degradation of the inner cell. The mechanisms beyond cellular cannibalism are still partially understoof but it appears to be of clinical relevance. Indeed, we have shown that these events could be modulated by anticancer treatments and there are evidences of their utility as a potent prognostic biomarker in some cancers. This thesis presents the in vitro experiments which led to the identification of the signaling pathways involved in cellular cannibalism induced by ionizing radiation.

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第20952号 / 理博第4404号 / 新制||理||1633(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 沼田 英治, 准教授 森 哲, 教授 中川 尚史 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM

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Cannibalism of offspring is a common yet seemingly paradoxical phenomenon observed across a wide variety of taxa. Behavioural ecologists have been particularly interested in understanding this behaviour within the context of parental care. This is because, superficially, offspring cannibalism appears counterproductive to the goals of a caring parent, which are often achieved by nurturing and protecting their young. Despite the prevalence of offspring cannibalism in many taxa, we still have a poor evolutionary understanding of this intriguing behaviour. Many hypotheses have been proposed explaining why parents may terminate and consume offspring, however, empirical tests of these hypotheses frequently return mixed results, and few examples exist in which multiple hypotheses for cannibalism have been tested using the same model study system. Over the course of my PhD thesis, I tested different cannibalism hypotheses in a novel study organism, the plainfin midshipman fish (Porichthys notatus), a species of paternal care-giving toadfish that frequently engages in offspring cannibalism. I first characterized the factors that underlie male reproductive success in this species to provide a broader understanding of their reproductive ecology and a background for the cannibalism studies in my later chapters. I showed that both male size and nest size are important correlates of male reproductive success (e.g. mate attraction, egg acquisition, and rearing success) in this system, and that morphological, physiological, and ecological variables can also have an impact on reproductive success (Chapter 2). Next, I conducted a series of field and laboratory studies to uncover the factors that select for offspring cannibalism in this species. In particular, I investigated whether offspring cannibalism serves to replenish dwindling energy reserves and/or occurs when paternity over a brood is likely to be low. I showed that although plainfin midshipman males endure a long and energetically taxing parental care period, they cannibalize offspring most frequently early in the breeding season, the time period when the males are in their best body condition but when male-male competition is also at its peak (Chapter 3). Using a direct comparison of males that had recently cannibalized offspring versus those that had not, I showed that the males with the lowest energy reserves were actually the least likely to have offspring in their digestive tracts, suggesting that offspring cannibalism is not driven by immediate energetic need (Chapter 4). I then tested whether males assess their paternity using direct or indirect offspring cues, and showed that males use the act of a nest take-over as reliable indirect cues of their paternity over a brood (Chapter 5). Altogether, my results further our understanding of the reproductive ecology of the plainfin midshipman fish, and provide a foundation upon which to assess and test between cannibalism hypotheses in this species and others. My thesis work demonstrates the advantage of studying multiple cannibalism hypotheses in a single study system, and through this approach we can gain a more accurate evolutionary understanding of how the phenomenon of offspring cannibalism is maintained in different species. / Thesis / Doctor of Philosophy (PhD)

The present thesis uses as its primary source of inspiration Argentine author Abel Posse's El largo atardecer del caminante (1992), which boasts the historically-based, unconventional Spanish conquistador, Álvar Núñez Cabeza de Vaca, as its main protagonist and narrator. I explore the juxtaposition of two opposing forms of metaphorical consumption in the novel. To highlight the first, I apply to the fictional Cabeza de Vaca the general concept of antropofagia cultural, or "cultural cannibalism," as described by Brazilian writer Oswald de Andrade in his "Manifesto Antropófago" (1928). I specifically examine the symbolic development of Posse's Cabeza de Vaca as the first latinoamericano via cultural anthropophagy. Over time, the life-altering experiences during the course of his wanderings in North and South America convert him into an antropófago cultural by virtue of his conscientious, metaphorical consumption of the Other. By extension, Cabeza de Vaca becomes a model for the first latinoamericano, wrought, not through miscegenation, but rather through cultural contact. The second kind of consumption, on the other extreme, is represented in the novel through sixteenth-century Spain and its quasi-literal, compulsive consumption and subsequent expulsion of the New World Other. This is seen through the optic of the fictional Cabeza de Vaca in his waning moments in Seville. Posse's rendition of Spain, as seen through his historically-inspired narrator, is representative of the metaphorical indigestion caused by a thoughtless consumption of products, practices, lands, and even people from the New World. I put on display the manner in which sixteenth-century Spain is portrayed in the novel as suffering a figurative bloating, consuming so much, so fast, seemingly growing large and powerful until it is ultimately revealed as being sick and weak.

At the beginnings of the Gothic, in the eighteenth century, there was an anxiety or taboo surrounding consumption and appetite for the Gothic text itself and for the excessive and sensational themes that the Gothic discussed. The female body, becoming a commodity in society, was objectified within the texts and consumed by the villain (both metaphorically and literally) who represented the perils of gluttony and indulgence and the horrors of cannibalistic desire. The female was the object of consumption and thus was denied appetite and was depicted as starved and starving. This also communicated the taboo of female appetite, a taboo that persists and changes within the Gothic as the female assumes the status of subject and the power to devour; she moves from being ethereal to bestial in the nineteenth century. With her renewed hunger, she becomes the consumer, devouring the villain who would eat her alive. The two sections of this study discuss the extremes of appetite and the extremes of bodily representations: starvation and cannibalism.

We study a discrete time, structured population dynamic model that is motivated by recent field observations concerning certain life history strategies of colonial- nesting gulls, specifically the glaucouswinged gull ( Larus glaucescens). The model focuses on mechanisms hypothesized to play key roles in a population's response to degraded environment resources, namely, increased cannibalism and adjustments in reproductive timing. We explore the dynamic consequences of these mechanics using a juvenile- adult structure model. Mathematically, the model is unusual in that it involves a high co- dimension bifurcation at R0 = 1 which, in turn, leads to a dynamic dichotomy between equilibrium states and synchronized oscillatory states. We give diagnostic criteria that determine which dynamic is stable. We also explore strong Allee effects caused by positive feedback mechanisms in the model and the possible consequence that a cannibalistic population can survive when a non- cannibalistic population cannot.

A presente dissertação se propõe a criar pontes entre certas manifestações das artes dramáticas contemporâneas e a Psicologia Cultural. Com esse fim, as próximas páginas se debruçarão sobre o projeto teatral Jaguar Cibernético, de autoria do teatrólogo Francisco Carlos, assim como sobre seu trabalho continuado dentro do teatro brasileiro por mais de 40 anos. Trataremos ainda das cercanias intelectuais, sociais e culturais de sua obra, que conta com mais de 40 espetáculos encenados, ainda pouco explorados pela Ciência / This text aims to create connections among certain contemporary theatre and Cultural Psychology. To achieve it, the next pages are going to discuss Jaguar Cibernético theatrical project, authored by Francisco Carlos, and also his continued work inside brazilian theatre for more than 40 years. We are going to present his works intelectual, social and cultural surroundings, composed by more than 40 spectacles ennacted, still unexplored by Science

O objetivo desse estudo foi avaliar o melhor nível de energia para poedeiras comerciais submetidas ou não a segunda debicagem, sobre o desempenho produtivo, qualidade de ovo e viabilidade econômica. Para tanto, foram utilizadas 640 poedeiras, distribuídas em delineamento inteiramente casualizado (DIC), em esquema fatorial 5x2 (nível de energia x número de debicagem) com oito repetições e oito aves por unidade experimental. Os níveis de energia estudados foram os seguintes: 2600; 2700; 2800; 2900; 3000 Kcal EM/ kg de ração. Com relação à debicagem, foi avaliado o efeito da realização da segunda debicagem, realizada aos 70 dias de idade, ou não e suas interações com os níveis nutricionais propostos. O período experimental foi conduzido da 20ª a 48ª semana de idade das poedeiras, totalizando 7 ciclos de 28 dias cada. Os dados de desempenho produtivo (produção de ovos, consumo de ração, massa de ovos, conversão alimentar por dúzia e conversão alimentar por massa de ovos), qualidade de ovos (peso, altura do albúmen, coloração de gema, unidade Haugh, resistência e espessura da casca), foram avaliados ao final de cada ciclo de 28 dias. Observou-se interações entre os níveis de energia e debicagem para as seguintes características: produção de ovos, altura de albúmen, unidade Haugh e espessura da casca. O aumento dos níveis de energia promoveram efeito significativo sobre o consumo de ração, conversão por dúzia e por massa de ovos, coloração de gema, resistência e espessura da casca. A debicagem afetou significativamente o consumo, conversão por dúzia e massa de ovos, peso dos ovos, coloração de gema e espessura de casca. A frequência de canibalismo não foi influenciada pelos níveis de energia e debicagem. Com relação à análise econômica tanto os níveis de energia com a debicagem tiveram efeito significativo sobre o custo total de produção, margem bruta e entre custo total sobre a receita total. Os resultados deste estudo demonstraram que o nível de energia mais baixo pode ser utilizado e constatou-se que há necessidade de realização da segunda debicagem do ponto de vista econômico. / The aim of this study was to evaluate the best energy level for layer hens submitted or not to the second beak trimming, on performance, egg quality and economic viability aspects. Therefore, 640 layers were distributed in a completely randomized design, in a factorial 5x2 (energy level x number of beak trimming) with eight replicates and eight birds per experimental unit. Energy levels studied were: 2600; 2700; 2800; 2900; 3000 Kcal EM / kg feed. Regarding the beak trimming, it was evaluated the effect of the second beak trimming performed at 70 days age, or not, and their interactions with the proposed nutrient levels. The trial was conducted from the 20th to 48th week of birds age, totaling 7 cycles of 28 days each. The data of productive performance (egg production, feed intake, egg mass, feed conversion per dozen and feed conversion by egg mass), egg quality (weight, albumen height, yolk color, Haugh unit, strength and shell thickness were evaluated at the end of each 28-day cycle. It was observed interactions between the energy levels and beak trimming to egg production, albumen height, Haugh unit, and shell thickness. Beak trimming significantly affected consumption, conversion per dozen and egg mass, egg weight, yolk color and shell thickness. The frequency of cannibalism was not influenced by energy levels or beak trimming. Regarding the economic analysis both energy levels and beak trimming had a significant effect on the total cost of production, gross margin and between total cost of the total revenue. Results showed that the lowest energy level can be used and it was found that there is need to carry out the second beak trimming by the economic point of view